WO2022110884A1 - 一种无线充电设备、充电底座及异物检测方法 - Google Patents

一种无线充电设备、充电底座及异物检测方法 Download PDF

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Publication number
WO2022110884A1
WO2022110884A1 PCT/CN2021/110254 CN2021110254W WO2022110884A1 WO 2022110884 A1 WO2022110884 A1 WO 2022110884A1 CN 2021110254 W CN2021110254 W CN 2021110254W WO 2022110884 A1 WO2022110884 A1 WO 2022110884A1
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Prior art keywords
relationship
wireless charging
value
transmitting coil
parameters
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PCT/CN2021/110254
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English (en)
French (fr)
Inventor
吴宝善
吴东昊
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华为数字能源技术有限公司
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Priority to EP21896391.6A priority Critical patent/EP4228124A1/en
Publication of WO2022110884A1 publication Critical patent/WO2022110884A1/zh
Priority to US18/323,146 priority patent/US20230299621A1/en

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J50/00—Circuit arrangements or systems for wireless supply or distribution of electric power
    • H02J50/60—Circuit arrangements or systems for wireless supply or distribution of electric power responsive to the presence of foreign objects, e.g. detection of living beings
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
    • G01R19/10—Measuring sum, difference or ratio
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J50/00—Circuit arrangements or systems for wireless supply or distribution of electric power
    • H02J50/10—Circuit arrangements or systems for wireless supply or distribution of electric power using inductive coupling
    • H02J50/12—Circuit arrangements or systems for wireless supply or distribution of electric power using inductive coupling of the resonant type
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J50/00—Circuit arrangements or systems for wireless supply or distribution of electric power
    • H02J50/80—Circuit arrangements or systems for wireless supply or distribution of electric power involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J50/00—Circuit arrangements or systems for wireless supply or distribution of electric power
    • H02J50/90—Circuit arrangements or systems for wireless supply or distribution of electric power involving detection or optimisation of position, e.g. alignment
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/00032—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries characterised by data exchange
    • H02J7/00034—Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B40/00—Technologies aiming at improving the efficiency of home appliances, e.g. induction cooking or efficient technologies for refrigerators, freezers or dish washers

Definitions

  • the present application relates to the technical field of wireless charging, and in particular, to a wireless charging device, a charging base and a foreign object detection method.
  • Wireless charging technology uses conductive media such as electric field, magnetic field, microwave or laser to realize wireless transmission of electric energy. Due to its advantages of no wire limitation and no plugging and unplugging, it is currently used in electronic equipment. more extensive. At present, more and more electronic devices use wireless charging devices to wirelessly charge them, for example, the electronic devices may be mobile phones, wearable devices, and the like.
  • the wireless charging device includes a transmitting coil, and the electronic device includes a receiving coil.
  • the wireless transmission of electrical energy is realized through electromagnetic field coupling between the transmitting coil and the receiving coil.
  • the principle of wireless charging technology is to transmit electrical energy through the magnetic field coupling between the transmitting coil at the transmitting end and the receiving coil at the receiving end.
  • the wireless charging device refers to a wireless charger
  • the electronic device refers to a mobile phone.
  • the transmitting coil is located in the wireless charger
  • the receiving coil is located inside the mobile phone.
  • foreign object detection FOD, Foreign Object Detection
  • FOD Foreign Object Detection
  • the widely used FOD includes the power loss method (Ploss, Power loss method) and the Q value method.
  • Ploss is a method for foreign object detection defined in the Qi protocol by the Wireless Power Consortium (WPC, Wireless power consortium).
  • WPC Wireless Power Consortium
  • Ploss is obtained by using the alternating current impedance of the transmitting coil.
  • the Q value method is to obtain the current Q value and compare it with the Q value threshold to determine whether there is foreign matter.
  • the current foreign object detection technology does not consider the influence of the relative positions of the transmitting end and the receiving end, and currently does not provide a method for accurately obtaining the relative position between the transmitting end and the receiving end.
  • the present application provides a wireless charging device, a charging base and a foreign object detection method, which can detect foreign objects and ensure the accuracy of the detection results.
  • the embodiments of the present application provide a wireless charging device, and the implementation type of the wireless charging device is not specifically limited, for example, it may be a wireless charger.
  • the wireless charging device is used to wirelessly charge electronic devices, and the electronic devices may be devices that can be wirelessly charged, such as mobile phones, tablets, and watches.
  • a wireless charging device which includes: a resonant network, an inverter circuit and a controller; the resonant network includes a resonant capacitor and a transmitting coil; the input end of the inverter circuit is used to connect the DC power supply, and the inverter circuit
  • the output terminal of the wireless charging device is used to connect the resonant network; therefore, the controller of the wireless charging device receives the electronic device parameters sent by the electronic device, and the electronic device parameters are the parameters pre-stored in the electronic device. Fit the deviation relationship between the Q value of the wireless charging device and the position space according to the parameters of the wireless charging device and the electronic device.
  • the parameters of the electronic device include: the Q1 value of the wireless charging device and the resonant frequency f1 of the resonant network when at least one relative position between the transmitting coil and the receiving coil is free of foreign objects;
  • the parameters of the wireless charging device include: wireless charging The initial Q value Q0 of the wireless charging device and the initial resonant frequency f0 of the resonant network in the uncoupled state of the device and the electronic device; the controller can perform foreign object detection according to the fitted deviation relationship.
  • the non-coupling state here means that there is no magnetic field coupling between the transmitting coil and the receiving coil, and no energy is transmitted, that is, the transmitting coil and the receiving coil are far away.
  • the wireless charging device Since the Q value threshold is related to the relative position, the Q value threshold corresponding to different relative positions is different. In order to detect foreign objects more accurately, the fixed Q value threshold cannot be used for foreign object detection.
  • the wireless charging device provided by the embodiment of the present application does not need to store the correspondence between the Q value and the entire location space, and similarly, does not need to store the correspondence between the AC impedance of the transmitting coil and the entire location space.
  • the wireless charging device can obtain the corresponding relationship between the Q value and the entire position space by fitting only according to the pre-stored limited number of parameters and the pre-stored limited number of parameters received from the electronic device.
  • the corresponding Q value threshold is obtained from the deviation relationship, so that foreign object detection is performed according to the Q value threshold corresponding to the current phase position.
  • the embodiment of the present application realizes the linearization of the Q value threshold. Since the electronic device parameters are received from the electronic device when fitting the deviation relationship, the deviation relationship for different electronic devices is different, thereby realizing the normalization of different electronic devices. Therefore, the wireless charging device provided by the embodiment of the present application can not only realize the accurate detection of foreign objects, but also does not need to store a large amount of data, which reduces the requirements on hardware performance and storage space. This application is applicable to a variety of different electronic devices, as long as the electronic devices support wireless charging.
  • the controller may perform foreign object detection before wireless charging, that is, obtain a Q value threshold according to the deviation relationship, and perform Q value foreign object detection according to the Q value threshold before the wireless charging device charges the electronic device.
  • the controller can perform foreign object detection during the wireless charging process, that is, obtain the Q value threshold according to the deviation relationship, and obtain the corresponding AC value according to the Q value threshold value and the corresponding relationship between the Q value and the AC impedance of the transmitting coil Impedance; Ploss foreign object detection is performed according to the obtained AC impedance during the charging process of the wireless charging device for the electronic device.
  • the corresponding relationship may be a proportional relationship or a linear proportional relationship. In addition, it can also be a variation of a proportional relationship, which is not limited in the embodiments of the present application.
  • the corresponding AC impedance can be obtained according to the obtained Q value threshold, and it is not necessary to fit the AC impedance.
  • the deviation of impedance relative to the entire location space Since there is a corresponding mapping relationship between the Q value and the AC impedance, the corresponding AC impedance can be obtained according to the obtained Q value threshold, and it is not necessary to fit the AC impedance. The deviation of impedance relative to the entire location space.
  • the wireless charging device in the embodiment of the present application can perform foreign object detection before charging, foreign object detection during charging, foreign object detection only before charging, and foreign object detection only during charging. Perform foreign body detection.
  • the deviation relationship includes: the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located; the controller fits the vertical relationship of the Q value relative to the position space according to f0, Q0 and Q1 values and f1 A direct relationship; the Q value threshold is obtained through the vertical relationship, and the corresponding AC impedance is obtained according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil.
  • the deviation relationship only includes the vertical relationship, it is especially suitable for the transmitter coil and the receiver coil to have no deviation in the radial direction, or the deviation can be ignored, and only the influence of the vertical relative position on the Q value threshold and the AC impedance can be considered.
  • the transmitter coil can be moved to align with the receiver coil in the radial direction.
  • the electronic device parameters include the following Q1 values and f1 for at least two relative positions between the transmitting coil and the receiving coil: Q11 and f11 at the first position, Q12 and f12 at the second position; deviation relationship Including: the radial horizontal relationship between the transmitting coil and the receiving coil and the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located; the controller fits the Q value relative to the position space according to Q11, f11, Q12 and f12.
  • pre-stored coupling parameters are added to the fitting deviation relationship in this embodiment.
  • the deviation relationship includes: the radial horizontal relationship between the transmitting coil and the receiving coil and the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located; the electronic equipment parameters also include: at least one relative position between the transmitting coil and the receiving coil.
  • the Q value threshold is obtained from the relationship and the horizontal relationship, and the
  • two pre-stored coupling parameters of relative positions are added in this embodiment, so that the fitted deviation relationship is more accurate. It should be understood that the pre-stored coupling parameters are pre-stored, and are not obtained by online testing in the corresponding coupling state during charging.
  • the electronic equipment parameters include the following Q1 values and f1 for at least two relative positions between the transmitting coil and the receiving coil: Q11 and f11 in the first position, Q12 and f12 in the second position; the deviation relationship includes: between the transmitting coil and the receiving coil The horizontal relationship in the radial direction and the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located; the parameters of the electronic device also include: pre-stored coupling parameters at the first position and pre-stored coupling parameters at the second position;
  • the pre-stored coupling parameters include at least the following One item: coupling coefficient and mutual inductance between the transmitting coil and the receiving coil; the controller fits the horizontal relationship between the Q value and the position space according to Q11, Q12, the pre-stored coupling parameters of the first position and the pre-stored coupling parameters of the second position; Fit the vertical relationship of the Q value with respect to the position space by any of the following methods: according to f0, Q0, Q11 and f11; or
  • the deviation relationship only includes a vertical relationship
  • the following technical solution is especially applicable.
  • the Q value threshold is obtained through the vertical relationship, and the corresponding AC impedance is obtained according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil.
  • the controller obtains the coupling parameters of the wireless charging device and the electronic device in the coupled state and the self-inductance L1 of the transmitting coil;
  • the coupling parameters in the coupling state include at least one of the following: the transmitting coil and the receiving coil The coupling coefficient and mutual inductance between the two;
  • the Q value threshold is obtained through the deviation relationship according to the coupling parameters in the coupling state and L1, and the corresponding AC impedance is obtained according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil;
  • the coupling state The coupling parameters below have a monotonic relationship with the horizontal relationship, and L1 has a monotonic relationship with the vertical relationship. It should be understood that the coupling parameters here are the coupling parameters obtained from the online test, not the pre-stored coupling parameters.
  • the controller specifically for receiving the wireless charging device sent by the electronic device and the electronic device in the coupled state, receives the self-inductance L2 of the coil;
  • the coupling parameters in the coupling state are obtained from the rectified voltages corresponding to the sense L1, L2 and the receiving coil.
  • the controller is specifically used to receive the wireless charging device sent by the electronic device and the electronic device in the uncoupled state of the receiving coil's self-inductance L20; according to the self-inductance L1 of the transmitting coil in the coupled state, the The self-inductance L10 and L20 of the transmitting coil in the coupling state obtain the self-inductance L2 of the receiving coil in the coupling state, and the coupling parameters in the coupling state are obtained according to the rectified voltage corresponding to L1, L2 and the receiving coil.
  • the controller 32 can obtain the self-inductance L2 of the receiving coil in the coupled state according to the self-inductance L10 of the transmitting coil in the uncoupled state, the self-inductance L1 and L20 of the transmitting coil in the coupled state and a preset proportional relationship.
  • the electronic device does not need to obtain L2, only L20.
  • the controller is further configured to receive the wireless charging device sent by the electronic device and the self-inductance L3 of the auxiliary coil in the coupled state of the electronic device;
  • the coupling parameters in the coupling state are obtained from the rectified voltages corresponding to the sense L1, L3 and the auxiliary coil.
  • the controller is further configured to receive the wireless charging device sent by the electronic device and the self-inductance L30 of the auxiliary coil in the uncoupled state of the electronic device;
  • the self-inductance L10 and L30 of the transmitting coil in the coupling state obtain the self-inductance L3 of the auxiliary coil in the coupling state, and the coupling parameters in the coupling state are obtained according to the rectified voltage corresponding to L1, L3 and the auxiliary coil.
  • the controller can obtain the self-inductance L3 of the auxiliary coil in the coupled state according to the self-inductance L10 of the transmitting coil in the uncoupled state, the self-inductance L1 and L30 of the transmitting coil in the coupled state and a preset proportional relationship.
  • the electronic device does not need to obtain L3, that is, L30.
  • the controller is further configured to obtain a coupling parameter of the wireless charging device and the electronic device in a coupled state, and is specifically configured to perform Ploss foreign object detection according to the AC impedance and the coupling parameter in the coupled state.
  • the coupling coefficient k After the coupling coefficient k is obtained, the power loss corresponding to the current coupling coefficient k can be accurately calculated online. The higher the accuracy, the higher the applicable wireless charging power, and therefore the higher power wireless charging can be supported.
  • the method further includes: a current detection circuit of the transmitting coil; a current detection circuit for detecting the voltage difference across the resonance capacitor; and a controller for obtaining the current of the transmitting coil according to the voltage difference.
  • the current detection circuit includes: a first voltage detection circuit, a second voltage detection circuit, and a differential circuit; a voltage detection circuit for detecting the first voltage of the first end of the resonance capacitor, dividing the first voltage and sending it to the first input end of the differential circuit; a second voltage detection circuit for detecting the second voltage of the resonance capacitor The second voltage of the terminal, the second voltage is divided and sent to the second input terminal of the differential circuit; the differential circuit is used to obtain the differential result between the voltage input at the first input terminal and the voltage input at the second input terminal; the controller, Used to obtain the current of the transmit coil from the differential result. That is, in this embodiment, in order to obtain the current of the transmitting coil connected to the full-bridge inverter circuit more accurately, the sampling form of the differential circuit is adopted.
  • the controller is further configured to determine the horizontal relative position and the vertical relative position between the transmitting coil and the receiving coil according to the self-inductance and coupling parameters of the transmitting coil, and move the transmitting coil according to the horizontal relative position, Align the transmitting coil with the receiving coil; the self-inductance of the transmitting coil has a monotonic relationship with the vertical relative position, and the coupling parameter has a monotonic relationship with the horizontal relative position.
  • the controller is specifically configured to obtain two horizontal relative positions corresponding to the wireless charging device and the electronic device at two different relative positions, and obtain a first circle whose radius is the two horizontal relative positions respectively and the second circle, obtain the intersection of the first circle and the second circle, and control the transmitting coil to align to the intersection.
  • the controller is further configured to move the transmitting coil to a third position, where the third position is different from two different relative positions; obtain at least one of the following parameters in the moving process, according to the at least one parameter The changing trend of , determines the cross point where the transmitting coil is aligned; at least one parameter includes: coupling parameter, charging efficiency, self-inductance of the transmitting coil, current of the transmitting coil and output voltage of the receiving end.
  • the controller is specifically configured to control the transmitting coil to move to a fourth position, where the fourth position and the two different relative positions are not in the same straight line, to obtain the self-inductance and coupling of the transmitting coil corresponding to the fourth position parameters; determine the horizontal relative position and the vertical relative position according to the self-inductance and coupling parameters of the transmitting coil corresponding to the fourth position, determine the third circle according to the horizontal relative position, and control the transmitting coil to move to the common point of the third circle and the intersection.
  • it further includes: an alignment mechanism; and a controller for controlling the alignment mechanism to drive the transmitting coil, so as to align the transmitting coil and the receiving coil.
  • an alignment mechanism for controlling the alignment mechanism to drive the transmitting coil, so as to align the transmitting coil and the receiving coil.
  • the specific implementation form of the alignment mechanism is not limited in the embodiments of the present application.
  • the controller is further configured to obtain the Q value threshold through the deviation relationship according to the self-inductance of the transmitter coil, and obtain the Q value threshold through the difference between the Q value and the AC impedance of the transmitter coil
  • the proportional relationship between the two is obtained according to the Q value threshold to obtain the corresponding AC impedance; before the wireless charging device charges the electronic device, the Q value foreign object detection is performed according to the Q value threshold, and during the wireless charging device is charging the electronic device according to the AC impedance and the coupling state
  • the coupling parameters of Ploss are used for foreign body detection.
  • the Ploss foreign object detection is performed according to the AC impedance and the coupling parameters in the coupling state, and the power loss of the wireless charging is obtained specifically by the following formula;
  • f(TxACR,k,I1) (a+TxACR*f(k))*I1 2 +b*I1+c;
  • Vin is the bus voltage of the inverter circuit
  • TxACR is the AC impedance ACR of the transmitting coil
  • I1 is the current of the transmitting coil
  • a, b, c, and d are the known parameters of the wireless charging device. Since a new parameter is introduced in the Ploss foreign object detection in this embodiment, that is, the coupling parameter in the coupled state, an accurate coefficient k can be obtained by using the coupling parameter, so as to obtain accurate power consumption, and then accurate foreign object detection can be performed. When the detection result is more accurate, it can be applied to foreign object detection corresponding to greater wireless charging power.
  • the embodiment of the present application also provides a wireless charging base, including: for wirelessly charging electronic devices, including: a power interface, a resonant network, an inverter circuit, a controller and a transmitting coil chassis; a power interface for connecting an adapter to transmit
  • the resonant network includes the resonant capacitor and the transmitting coil; the transmitting coil chassis is used to place the transmitting coil; the input end of the inverter circuit is used to connect the power interface, and the output end of the inverter circuit is used to connect the resonant network;
  • the controller with For receiving the electronic device parameters sent by the electronic device, fit the deviation relationship between the Q value of the wireless charging device and the position space according to the wireless charging device parameters and the electronic device parameters, and the position space is the position between the transmitting coil and the receiving coil of the electronic device.
  • the parameters of the electronic device include: the Q1 value of the wireless charging device and the resonant frequency f1 of the resonant network when at least one relative position between the transmitting coil and the receiving coil is free of foreign objects;
  • the parameters of the wireless charging device include: the wireless charging device is not related to the electronic device.
  • the initial Q value Q0 of the wireless charging device in the coupled state and the initial resonance frequency f0 of the resonant network; the controller is also used to detect foreign objects according to the deviation relationship.
  • the wireless charging base is a charging disc or a three-dimensional charging base, and the specific geometric form of the wireless charging base is not specifically limited in the embodiments of the present application.
  • the general wireless charging base can be parallel to the horizontal plane, and the electronic device is placed above the wireless charging base.
  • the wireless charging base is vertical to the horizontal plane, the plane where the electronic device is located needs to be parallel to the plane where the wireless charging base is located, so that the transmitting coil and the receiving coil can be better coupled.
  • the controller is specifically configured to obtain the Q-value threshold according to the deviation relationship, and perform the Q-value foreign object detection according to the Q-value threshold before the wireless charging device charges the electronic device.
  • the controller is specifically configured to obtain the Q value threshold according to the deviation relationship, and obtain the corresponding AC impedance according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil; when the wireless charging device is During the charging process of electronic equipment, Ploss foreign matter detection is performed according to the obtained AC impedance.
  • the electronic device parameters include the following Q1 values and f1 for at least two relative positions between the transmitting coil and the receiving coil: Q11 and f11 at the first position, Q12 and f12 at the second position; deviation relationship Including: the radial horizontal relationship between the transmitting coil and the receiving coil and the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located; the controller is specifically used to fit the relative Q values according to Q11, f11, Q12 and f12 the horizontal relationship in position space; fit the vertical relationship of Q value relative to position space by either: according to f0, Q0, Q11, and f11; or, fit Q value relative to f0, Q0, Q12, and f12 The vertical relationship of the position space; or, according to the Q and f corresponding to at least one point in Q0, f0 and the horizontal relationship, the vertical relationship of the Q value relative to the position space is fitted; the Q value threshold is obtained through the horizontal relationship and the vertical relationship , and obtain
  • the electronic device parameters include the following Q1 values and f1 for at least two relative positions between the transmitting coil and the receiving coil: Q11 and f11 at the first position, Q12 and f12 at the second position; deviation relationship Including: the radial horizontal relationship between the transmitting coil and the receiving coil and the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located; the electronic equipment parameters also include: the pre-stored coupling parameters of the first position and the pre-stored coupling parameters of the second position Coupling parameters; the pre-stored coupling parameters include at least one of the following: coupling coefficient and mutual inductance between the transmitting coil and the receiving coil; the controller is specifically used for the pre-stored coupling parameters according to Q11, Q12, the pre-stored coupling parameters at the first position and the pre-stored coupling at the second position
  • the parameters fit the horizontal relationship of the Q value with respect to the position space; fit the vertical relationship of the Q value with respect to the position space by either: according to
  • the embodiment of the present application also provides a method for detecting foreign objects in wireless charging, which is applied to a wireless charging device.
  • the wireless charging device includes: a resonant network and an inverter circuit; the resonant network includes a resonant capacitor and a transmitting coil; the input end of the inverter circuit is used for The DC power supply is connected, and the output end of the inverter circuit is used to connect to the resonance network; the method includes: receiving electronic equipment parameters sent by the electronic equipment; fitting the Q value of the wireless charging equipment relative to the position space according to the wireless charging equipment parameters and the electronic equipment parameters
  • the position space is the position space between the transmitting coil and the receiving coil of the electronic device; the parameters of the electronic device include: Q1 value and resonance of the wireless charging device when at least one relative position between the transmitting coil and the receiving coil is free of foreign objects
  • the resonant frequency f1 of the network; the parameters of the wireless charging device include: the initial Q value Q0 of the wireless charging device and the initial resonant
  • performing foreign object detection according to the deviation relationship specifically includes: obtaining a Q value threshold according to the deviation relationship, and performing Q value foreign object detection according to the Q value threshold before the wireless charging device charges the electronic device.
  • performing foreign object detection according to the deviation relationship specifically includes: obtaining a Q value threshold according to the deviation relationship; obtaining a corresponding AC impedance according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil;
  • the wireless charging device performs Ploss foreign object detection according to the obtained AC impedance during the charging process of the electronic device.
  • the electronic device parameters include the following Q1 values and f1 for at least two relative positions between the transmitting coil and the receiving coil: Q11 and f11 at the first position, Q12 and f12 at the second position; deviation relationship Including: the radial horizontal relationship between the transmitting coil and the receiving coil and the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located; the Q value of the wireless charging device is fitted according to the wireless charging device parameters and electronic device parameters relative to The deviation relationship of the position space, specifically including: fitting the horizontal relationship of the Q value with respect to the position space according to Q11, f11, Q12 and f12; fitting the vertical relationship of the Q value with respect to the position space by any of the following methods: according to f0, Q0, Q11 and f11; or, according to f0, Q0, Q12 and f12, fit the vertical relationship of Q value with respect to the position space; or, according to Q0, f0 and at least one point in the horizontal relationship corresponding
  • the deviation relationship includes: the radial horizontal relationship between the transmitting coil and the receiving coil and the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located; the parameters of the electronic device further include: the transmitting coil Pre-stored coupling parameters when there is no foreign matter in at least one relative position with the receiving coil; the pre-stored coupling parameters include at least one of the following: coupling coefficient and mutual inductance between the transmitting coil and the receiving coil; fitting according to wireless charging device parameters and electronic device parameters The deviation relationship between the Q value of the wireless charging device and the position space, specifically including: fitting the vertical relationship between the Q value and the position space according to f0, Q0, and the Q value and f of at least one relative position between the transmitting coil and the receiving coil ; Fitting the horizontal relationship of the Q value with respect to the position space according to the pre-stored coupling parameters and the Q value of at least one relative position between the transmitting coil and the receiving coil; Obtaining the Q value threshold according to the deviation relationship
  • the electronic device parameters include the following Q1 values and f1 for at least two relative positions between the transmitting coil and the receiving coil: Q11 and f11 at the first position, Q12 and f12 at the second position; deviation relationship Including: the radial horizontal relationship between the transmitting coil and the receiving coil and the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located; the electronic equipment parameters also include: the pre-stored coupling parameters of the first position and the pre-stored coupling parameters of the second position coupling parameters; the pre-stored coupling parameters include at least one of the following: coupling coefficient and mutual inductance between the transmitting coil and the receiving coil; fitting the deviation relationship between the Q value of the wireless charging device and the position space according to the parameters of the wireless charging device and the parameters of the electronic device, Specifically, it includes: fitting the horizontal relationship of the Q value with respect to the position space according to Q11, Q12, the pre-stored coupling parameters of the first position and the pre-stored coupling parameters of
  • the Q value corresponds to different Q thresholds at different relative positions of the transmitting coil and the receiving coil, using different Q value thresholds for foreign object judgment will affect the judgment result.
  • the influence of the relative position on the Q value threshold is considered, and the detection of foreign objects is performed according to the Q value threshold corresponding to the relative position, which can make the foreign object detection result more accurate. Since there is a corresponding relationship between the Q value and the relative position, the corresponding Q value threshold can be obtained according to the relative position of the transmitting coil and the receiving coil.
  • the controller uses the Q1 value and the resonant frequency f1 when there is no foreign matter in at least one relative position of the transmitting coil and the receiving coil, and the initial Q value Q0 and the initial resonant frequency f0 in the uncoupled state to obtain the deviation of the Q value relative to the entire position space. After obtaining the deviation relationship of the Q value relative to the entire position space, foreign objects can be detected at the current position through the deviation relationship.
  • FIG. 1 is a schematic diagram of a wireless charging system provided by an embodiment of the present application
  • Fig. 2 is the structural representation of the electronic device in Fig. 1;
  • FIG. 3 is a schematic circuit diagram of a wireless charging system provided by an embodiment of the present application.
  • FIG. 4 is an equipotential diagram of the AC impedance of a transmitting coil changing with relative position according to an embodiment of the present application
  • Fig. 5 is a kind of equipotential diagram of the change of the Q value of the transmitting end with the relative position when there is no foreign matter provided by the embodiment of the present application;
  • FIG. 6 is a schematic diagram of a wireless charging device according to an embodiment of the present application.
  • FIG. 7 is a schematic diagram of the relationship between the self-inductance L1 of the transmitting coil and the relative position according to an embodiment of the present application;
  • FIG. 10 is a schematic diagram of a wireless charging system provided by an embodiment of the present application.
  • FIG. 11 is a circuit diagram for detecting the current of a transmitting coil according to an embodiment of the application.
  • FIG. 12 is a circuit diagram for detecting the current of another transmitting coil provided by an embodiment of the application.
  • FIG. 13 is a schematic diagram of another wireless charging device provided by an embodiment of the present application.
  • FIG. 14 is a schematic diagram of an alignment structure provided by an embodiment of the present application.
  • FIG. 15 is a schematic diagram of the alignment principle of a transmitting coil according to an embodiment of the application.
  • 16 is a schematic diagram of a wireless charging device with a mechanical card position provided by an embodiment of the application.
  • 17 is a schematic diagram of a wireless charging device with magnetic alignment provided by an embodiment of the present application.
  • FIG. 18 is a flowchart of a foreign object detection method for wireless charging provided by an embodiment of the present application.
  • FIG. 19 is a flowchart of still another method for detecting foreign objects in wireless charging provided by an embodiment of the present application.
  • 20 is a flowchart of another method for detecting foreign objects in wireless charging provided by an embodiment of the present application.
  • FIG. 21 is a flowchart of another foreign object detection method for wireless charging provided by an embodiment of the present application.
  • 22 is a flowchart of a foreign object detection method before alignment provided by an embodiment of the present application.
  • FIG. 24 is a schematic diagram of a wireless charging system provided by an embodiment of the present application.
  • directional terms such as “upper” and “lower” may include, but are not limited to, definitions relative to the schematic placement of components in the drawings. It should be understood that these directional terms may be relative concepts, They are used for relative description and clarification, which may vary accordingly depending on the orientation in which the components are placed in the drawings.
  • connection should be understood in a broad sense.
  • connection may be a fixed connection, a detachable connection, or an integrated body; it may be directly connected, or Can be indirectly connected through an intermediary.
  • coupled may be a manner of electrical connection that enables signal transmission.
  • Coupling can be a direct electrical connection or an indirect electrical connection through an intermediate medium.
  • the electronic device may be a mobile phone, a tablet computer (pad), a computer with a wireless transceiver function, a smart wearable product (for example, a smart watch, a smart bracelet, a headset, etc. ), virtual reality (VR) terminal devices, augmented reality (AR) terminal devices, etc. have wireless devices.
  • the above-mentioned electronic devices may also be electronic products such as wirelessly charged electric vehicles, wirelessly charged household appliances (eg, soymilk maker, sweeping robot), and unmanned aerial vehicles.
  • the following first introduces an application scenario of wireless charging of electronic devices, taking the electronic device as a mobile phone as an example for introduction.
  • FIG. 1 this figure is a schematic diagram of a wireless charging system provided by an embodiment of the present application.
  • the wireless charging device is a wireless charger 02
  • the wireless charger 02 is used to wirelessly charge the electronic device 01 (ie, the mobile phone).
  • the illustrated wireless charger 02 supports the electronic device 01 to be placed horizontally above it.
  • the wireless charger 02 may also have other shapes, such as a vertical wireless The device 01 can rest against the wireless charger 02 .
  • the wireless charging system includes a wireless charging receiving (Receive, RX) device 20 disposed in the electronic device 01 and a battery 50 coupled to the wireless charging receiving end 20 .
  • RX wireless charging receiving
  • the wireless charging system further includes a wireless charging transmitter (Transmit, TX) terminal 30 disposed in the wireless charger 02, and an adapter 40 coupled to the wireless charging transmitter 30, and the adapter 40 is used for providing charging power.
  • a wireless charging transmitter Transmit, TX
  • an adapter 40 coupled to the wireless charging transmitter 30, and the adapter 40 is used for providing charging power.
  • the wireless charging transmitter 30 transmits power to the wireless charging receiver 20 ; control signals or charging data may be transmitted between the wireless charging transmitter 30 and the wireless charging receiver 20 . Transmission of control signals or transmission of charging data can be achieved through in-band communication or out-of-band communication.
  • the wireless charging transmitter 30 and the wireless charging receiver 20 are connected through Bluetooth (Bluetooth), wireless broadband (Wireless-Fidelity, WiFi), Zigbee protocol (Zigbee), radio frequency identification technology (Radio Frequency Identification, RFID), long-distance (Long) Range, Lora) wireless technology or near field communication technology (Near Field Communication, NFC) and other out-of-band communication methods to achieve wireless connection, so that wireless communication can be established between the wireless charging transmitter 30 and the wireless charging receiver 20.
  • This charging data can be used to indicate the type of charging.
  • the charging data may be a charging protocol, such as a wireless charging standard Qi introduced by the Wireless Power Consortium (WPC), such as a BPP (Basic Power Profile) protocol, or an EPP (Extended Power Profile) protocol, etc. .
  • WPC Wireless Power Consortium
  • BPP Basic Power Profile
  • EPP Extended Power Profile
  • FIG. 2 the figure is a schematic structural diagram of the electronic device in FIG. 1 .
  • the electronic device 01 mainly includes a display panel (Display Panel, DP) 10 .
  • the display screen 10 may be a liquid crystal display (Liquid Crystal Display, LCD) screen, or an organic light emitting diode (Organic Light Emitting Diode, OLED) display screen, etc.
  • the mobile phone adopts a folding screen structure or a multi-screen structure, the mobile phone may also include
  • the multiple screens may also be a combination of the above different types of screens, which is not limited in this application.
  • the above electronic device 01 may further include a middle frame 11 and a housing 12 .
  • the display screen 10 and the casing 12 are respectively located on two sides of the middle frame 11 , the back of the display screen 10 faces the casing 12 , and the display screen 10 and the casing 12 are connected through the middle frame 11 .
  • the middle frame 11 includes a carrier board 110 and a frame 111 surrounding the carrier board 110 .
  • the electronic device 01 may also include a printed circuit board (Printed Circuit Boards, PCB).
  • the transmitting coil and the receiving coil are generally set in the shape of a disc.
  • FIG. 3 is a schematic circuit diagram of a wireless charging system provided by an embodiment of the present application.
  • the wireless charging transmitter 30 is used for transmitting magnetic field energy.
  • the wireless charging transmitter 30 may be located in the wireless charging device.
  • the wireless charging transmitter 30 includes an inverter circuit DC/AC31.
  • the input end of the inverter circuit DC/AC31 is used to connect to a DC power source, such as the DC power output by the adapter, and the output end of the inverter circuit DC/AC31 is connected to a resonant network.
  • the resonant network Including resonant capacitor C1 and transmitting coil L1.
  • the series resonance of the resonant capacitor C1 and the transmitting coil L1 is taken as an example.
  • the wireless charging receiving end 20 is used for receiving the magnetic field energy emitted by the wireless charging transmitting end 30 .
  • the wireless charging receiving end 20 may be located in the electronic device.
  • the wireless charging receiving end 20 includes a receiving coil L2, a capacitor C2 and a rectifier circuit AC/DC21.
  • the rectifier circuit AC/DC21 converts the alternating current output from the receiving coil L2 into direct current to charge the battery.
  • the wireless charging transmitter end is referred to as the transmitter end for short
  • the wireless charging receiver end is referred to as the receiver end for short.
  • the wireless charging device After the wireless charging device converts the input electrical energy into magnetic field energy, the wireless charging device transmits magnetic field energy through the wireless charging transmitter 30; when the electronic device is located near the wireless charging device, the electronic device receives the magnetic field emitted by the wireless charging device through the wireless charging receiver 20. energy, and convert the magnetic field energy into electrical energy to charge electronic devices. Thereby, wireless transmission of electrical energy from the wireless charging device to the electronic device is realized.
  • the wireless charging device and the electronic device communicate through in-band, it includes the communicable area and the non-communicable area.
  • the communicable area generally means that the plane position deviation of the transmitting coil and the receiving coil is within 10mm, and the Z-direction distance is also within 10mm, where the Z-direction distance refers to the wireless charging device.
  • the height distance from the electronic device for example, the transmitter coil is placed horizontally, the receiver coil is placed horizontally, the Z direction refers to the vertical distance between the transmitter coil and the receiver coil, and the Z direction deviation refers to the vertical relative position.
  • the transmitting coil when the transmitting coil is in the shape of a disk and the receiving coil is in the shape of a disk, when the wireless charging device is placed flat, the plane where the transmitting coil is located is parallel to the horizontal plane, and the mobile phone is placed on the wireless charging device, and the plane where the receiving coil is located is the plane where the transmitting coil is located.
  • the plane position deviation of the transmitting coil and the receiving coil refers to the deviation between the center of the transmitting coil and the center of the receiving coil on the plane, that is, the radial deviation, and the may be called the horizontal relative position.
  • the methods of foreign body detection usually include Ploss and Q-value methods.
  • the Ploss method obtains the AC impedance of the transmitting coil according to the horizontal relative position and the vertical relative position, obtains the power loss of the transmitting end according to the AC impedance of the transmitting coil and the current of the transmitting coil during the charging process, and obtains the transmitting end according to the input power of the transmitting end and the power loss of the transmitting end.
  • Power the foreign object loss is obtained according to the transmitting power and the receiving power of the receiving end. When the foreign object loss is greater than the power threshold, it is determined that there is a foreign object between the transmitting end and the receiving end.
  • the Q value has a monotonic relationship with the position deviation
  • the Ploss also has a monotonic relationship with the position deviation
  • FIG. 4 is an equipotential diagram of a change in AC impedance of a transmitting coil with a relative position according to an embodiment of the present application.
  • the abscissa is the horizontal relative position (unit: mm)
  • the ordinate is the vertical relative position (unit: mm)
  • the intersection of the dotted lines in the figure is the known horizontal relative position and vertical relative position, and the transmitter and receiver are determined.
  • the AC impedance of the transmitting coil when there is no foreign matter between the terminals 102 .
  • the relative position between the transmitting end and the receiving end 102 will affect the AC impedance of the transmitting coil.
  • FIG. 5 is an equipotential diagram of the change of the Q value of the transmitting end with the relative position when there is no foreign matter provided by an embodiment of the present application.
  • the abscissa is the horizontal relative position (unit: mm)
  • the ordinate is the vertical relative position (unit: mm)
  • the intersection of the dotted lines in the figure is the known horizontal relative position and vertical relative position
  • the transmitter and receiver are determined.
  • the Q value of the transmitting line end when there is no foreign matter between the ends.
  • the Q values of the transmitter corresponding to different relative positions are different.
  • both the Q value and the AC impedance have a monotonic relationship with the relative position. If there is no alignment between the transmitting coil and the receiving coil, that is, when there is a positional deviation, the Q value and Ploss used for foreign object detection The standard will change. If the influence of positional deviation is ignored, whether using Q value or Ploss for foreign object detection, it may lead to inaccurate foreign object detection. Therefore, in order to solve the problem of inaccurate foreign object detection caused by position deviation, it is necessary to perform FOD according to the Q value threshold corresponding to the current position to accurately detect foreign objects. In the same way, it is necessary to perform Ploss calculation according to the AC impedance corresponding to the current position, and to perform FOD according to the unified Ploss threshold to accurately detect foreign objects.
  • the foreign object detection of the wireless charging system uses the Q value to detect foreign objects before the wireless charging device charges the electronic device, and uses the Ploss to detect foreign objects during the charging process of the wireless charging device for the electronic device. Since there is a corresponding relationship between the Q value and the AC impedance of the transmitting coil, for example, there is a proportional relationship between the Q value and the AC impedance, the following is an example of the linear proportional relationship between the Q value and the AC impedance. Of course, other manifestations of the proportional relationship are also possible. form. Generally, the Q value can be obtained first, and then the AC impedance can be obtained according to the linear proportional relationship between the Q value and the AC impedance of the transmitting coil. The following is a detailed introduction in combination with the formula.
  • the Q value is defined as the following formula (1);
  • L 1 is the inductance value of the transmitting coil
  • R tx acr is the AC impedance of the transmitting coil
  • f is the resonant frequency of the resonant network of the wireless charging device.
  • the embodiments of the present application provide a wireless charging device, which does not need to store the corresponding relationship between the Q value and the entire location space, nor does it need to store the AC impedance of the transmitting coil and the entire location space. Correspondence in location space.
  • the wireless charging device can fit the corresponding relationship between the Q value and the entire location space based on only a limited number of parameters, which can reduce the requirements for hardware performance and storage space.
  • this figure is a schematic diagram of a wireless charging device provided by an embodiment of the present application.
  • the wireless charging device provided in this embodiment is used to wirelessly charge electronic devices, and the wireless charging device includes: a resonant network, an inverter circuit, and a controller 32;
  • the resonant network includes a resonant capacitor C1 and a transmitting coil L1; in this embodiment, the resonant network formed by the resonant capacitor C1 and the transmitting coil L1 in series is used as an example for introduction.
  • the input end of the inverter circuit is used to connect the DC power supply, and the output end of the inverter circuit is used to connect to the resonant network.
  • the inverter circuit is taken as an example of a full-bridge circuit for introduction.
  • the inverter circuit includes four controllable switch tubes, which are respectively a first switch tube S1 - a fourth switch tube S4. As shown in FIG. 6 , the first end of the first switch S1 is connected to the positive pole of the DC power supply, the second end of the first switch S1 is connected to the first end of the second switch S2, and the second end of the second switch S2 Connect the negative pole of the DC power supply, that is, S1 and S2 are connected in series between the positive pole and the negative pole of the DC power supply.
  • the first end of the third switch tube S3 is connected to the positive pole of the DC power supply
  • the second end of the third switch tube S3 is connected to the first end of the fourth switch tube S4
  • the second end of the fourth switch tube S4 is connected to the DC power supply
  • the negative pole, that is, S3 and S4 are connected in series between the positive pole and the negative pole of the DC power supply.
  • the second end of S1 is connected to the second end of S3 by connecting C1 and L1 in series.
  • L2 is a receiving coil of an electronic device.
  • the receiving coil L2 is located inside the mobile phone.
  • the controller 32 is configured to receive the electronic device parameters sent by the electronic device, and fit the deviation relationship between the Q value of the wireless charging device and the position space according to the wireless charging device parameters and the electronic device parameters, and the position space is the position space between the transmitting coil and the receiving coil of the electronic device; wherein the parameters of the electronic device include: the wireless charging when there is no foreign object in at least one relative position between the transmitting coil and the receiving coil The Q1 value of the device and the resonant frequency f1 of the resonant network; the parameters of the wireless charging device include: the initial Q value Q0 of the wireless charging device in the non-coupling state of the wireless charging device and the electronic device and the The initial resonant frequency f0 of the resonant network.
  • the controller After the controller obtains the deviation relationship, it is also used to detect foreign objects according to the deviation relationship.
  • the electronic device parameters are initial parameters pre-stored by the electronic device.
  • the electronic device is a mobile phone, which may be parameters that are pre-stored when the mobile phone leaves the factory.
  • the parameters of the electronic equipment include: the Q value and the resonant frequency f when there is no foreign matter in at least one position.
  • At least one position refers to the relative position between the wireless charging device and the electronic device.
  • it can be a parameter corresponding to one relative position, or a parameter corresponding to two positions, or a parameter corresponding to multiple positions. It can be understood that the more relative positions and the more corresponding parameters, the more accurate the fitted deviation relationship.
  • the Q value when there are no foreign objects in the two relative positions refers to the Q value measured by the mobile phone when the mobile phone is in two different positions relative to the wireless charger
  • the resonant frequency f when there are no foreign objects in the two positions refers to the mobile phone relative to the wireless charger.
  • the relative position between the wireless charging device and the electronic device is generally characterized by the relative position between the transmitting coil and the receiving coil.
  • the transmitting coil and the receiving coil are generally designed in the shape of disks, therefore, the relative position between the transmitting coil and the receiving coil refers to the positional deviation between the centers of the two disks. It can be understood that when the transmitting coil and the receiving coil are in other shapes, the relative position also refers to the positional deviation between the center of the transmitting coil and the center of the receiving coil.
  • the wireless charging device parameters are generally parameters pre-stored by the wireless charging device, such as parameters pre-stored by the wireless charger.
  • the parameters of the wireless charging device include: the initial Q value Q0 and the initial resonant frequency f0 in the non-coupling state of the wireless charging device and the electronic device.
  • the non-coupling state means that the distance between the wireless charging device and the electronic device is relatively far, and there is no electromagnetic coupling. That is, for the wireless charger, Q0 and f0 of the wireless charger when the mobile phone is not detected.
  • the controller 32 of the wireless charging device provided by the embodiment of the present application can fit the deviation relationship of the Q value relative to the entire position space according to a limited number of wireless charging device parameters and electronic device parameters, that is, fitting a Q value similar to that represented in FIG. 5 . Correspondence with respect to the horizontal relative position and the vertical relative position. Therefore, the wireless charging device does not need to store all the data of the Q value and the horizontal relative position and the Q value and the vertical relative position of the entire position space, thereby greatly reducing the storage space.
  • the controller 32 uses the Q1 value and the resonant frequency f1 when there is no foreign matter in at least one relative position, the initial Q value Q0 and the initial resonant frequency f0 in the non-coupling state to obtain the deviation relationship of the Q value relative to the entire position space, and obtain the relative Q value relative.
  • the Q value corresponding to the current position can be obtained through the deviation relationship, so as to perform foreign object detection according to the Q value. Since the Q value and the AC impedance of the transmitting coil have the relationship shown in formula (1), the corresponding AC impedance can be obtained from the Q value, that is, the deviation relationship of the AC impedance relative to the entire position space can be omitted.
  • the AC impedance can be converted to obtain the Ploss foreign object detection according to the AC impedance.
  • the Q-value foreign object detection can be performed before wireless charging, and the Ploss foreign object detection can be performed during the wireless charging process, which will be introduced separately below. It should be understood that, whether it is the Q-value foreign body detection or the Ploss foreign body detection, as long as the deviation relationship provided by the embodiments of the present application is used, they are all within the protection scope of the present application.
  • the controller obtains the Q-value threshold according to the deviation relationship, and performs the Q-value foreign object detection according to the Q-value threshold before the wireless charging device charges the electronic device.
  • the controller is specifically used to obtain the Q value threshold according to the deviation relationship, and obtain the corresponding AC impedance according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil; in the process of charging the electronic device by the wireless charging device, according to the obtained data
  • the above AC impedance is used for Ploss foreign body detection.
  • the relative position relationship of the Q value with respect to the entire space includes a horizontal relative position and a vertical relative position
  • the deviation relationship of the Q value fitted in the embodiment of the present application may include: a horizontal relationship and a vertical relationship. That is, the deviation relationship includes the radial horizontal relationship between the transmitting coil and the receiving coil and the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located.
  • the deviation relationship of the Q value may also only include a vertical relationship.
  • the deviation relationship includes: a horizontal relationship and a vertical relationship; wherein the electronic device parameters include the following Q1 values and f1 for at least two relative positions between the transmitting coil and the receiving coil: Q11 and f11 in the first position, and f11 in the second position of Q12 and f12;
  • the controller is specifically used to fit the horizontal relationship of the Q value relative to the position space according to Q11, f11, Q12 and f12;
  • the Q value threshold is obtained through the horizontal relationship and the vertical relationship, and the corresponding AC impedance is obtained according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil.
  • the deviation relationship includes: the radial horizontal relationship between the transmitting coil and the receiving coil and the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located;
  • the parameters of the electronic device further include: a pre-stored coupling parameter when at least one relative position between the transmitting coil and the receiving coil is free of foreign objects; the pre-stored coupling parameter includes at least one of the following: a difference between the transmitting coil and the receiving coil. coupling coefficient and mutual inductance between
  • a controller specifically configured to fit the vertical relationship of the Q value with respect to the position space according to the f0, the Q0, and the Q1 value and f1 of at least one relative position between the transmitting coil and the receiving coil; According to the pre-stored coupling parameters and the Q1 value of at least one relative position between the transmitting coil and the receiving coil, fit the horizontal relationship of the Q value with respect to the position space; obtain Q through the vertical relationship and the horizontal relationship The corresponding AC impedance is obtained according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil.
  • the difference between the second and the first is that the second uses the pre-stored coupling parameters of the receiving end when fitting the horizontal relationship. Since the second fitted horizontal relationship uses the pre-stored coupling parameters, the coupling parameters detected online can be used to obtain the corresponding horizontal relative position through the deviation relationship when the deviation relationship is used subsequently, that is, the coupling parameter and the horizontal relationship are monotonic, for example Using the coupling coefficient k of the online test, the corresponding horizontal relative position can be obtained through the deviation relationship, and since the horizontal relative position has a monotonic relationship with the Q value, the corresponding Q value threshold can be obtained. In addition, the Q value threshold can also be obtained directly according to the monotonicity of the relationship between k and the level, so the fitted horizontal relationship is the horizontal monotonic relationship between the Q value and the space.
  • the deviation relationship includes: the radial horizontal relationship between the transmitting coil and the receiving coil and the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located;
  • the electronic device parameters include the following Q1 values and f1 for at least two relative positions between the transmitting coil and the receiving coil: Q11 and f11 at the first position, and Q12 and f12 at the second position.
  • the electronic device parameters further include: pre-stored coupling parameters at the first position and pre-stored coupling parameters at the second position; the pre-stored coupling parameters include at least one of the following: coupling coefficient and mutual inductance between the transmitting coil and the receiving coil;
  • a controller specifically configured to fit the horizontal relationship between the Q value and the position space according to the Q11, the Q12, the pre-stored coupling parameters of the first position, and the pre-stored coupling parameters of the second position;
  • Fitting the vertical relationship of the Q value with respect to the position space in any of the following ways: according to the f0, the Q0, the Q11 and the f11; or, according to the f0, the Q0, the Q12 and the f12 fit the vertical relationship of the Q value with respect to the position space; or, fit the Q value relative to the Q and f corresponding to at least one point in the Q0, the f0 and the horizontal relationship
  • the vertical relationship in the position space; the Q value threshold is obtained through the vertical relationship and the horizontal relationship, and obtained according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil corresponding to the AC impedance.
  • the third method is the same as the second method in that the pre-stored coupling parameters in the parameters of the electronic equipment are used when fitting the horizontal relationship.
  • the difference between the third method and the second method is that the electronic device parameters of the second method include at least one position, and the horizontal relationship can also be fitted only by using the pre-stored coupling parameters of one position.
  • the electronic device parameters include at least two positions, that is, using pre-stored coupling parameters at two different positions and Q and f at two different positions to fit the horizontal relationship. Since the third method uses more parameters to fit the horizontal relationship, the horizontal relationship fitted by the third method is more accurate.
  • the coupling parameters detected online can be used to obtain the corresponding horizontal relative position through the deviation relationship when the deviation relationship is used subsequently, that is, the coupling parameter and the horizontal relationship are monotonic, for example
  • the coupling coefficient k of the online test the corresponding horizontal relative position can be obtained through the deviation relationship, and since the horizontal relative position has a monotonic relationship with the Q value, the corresponding Q value threshold can be obtained.
  • the Q value threshold can also be obtained directly according to the monotonicity of the relationship between k and the level, so the fitted horizontal relationship is the horizontal monotonic relationship between the Q value and the space.
  • the deviation relationship includes: the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located;
  • the controller fits a vertical relationship according to f0, Q0 and the Q1 value and f1 in the parameters of the electronic equipment; the Q value threshold and the AC impedance are obtained through the vertical relationship.
  • the following describes a specific implementation manner in which the controller uses the parameters of the electronic device and the parameters of the wireless charging device to fit the vertical relationship.
  • the deviation relationship includes: a vertical relationship; wherein the electronic device parameter includes the Q1 value and f1 of at least one of the following positions.
  • a controller specifically configured to fit the vertical relationship of the Q value with respect to the position space according to the f0, the Q0 and the Q1 value and the f1; obtain the Q value threshold through the vertical relationship , and obtain the corresponding AC impedance according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil.
  • the wireless charging device has an automatic alignment function.
  • the controller can control the movement of the transmitter coil and then align it with the receiver coil. When aligned, the horizontal relative position between the transmitter coil and the receiver coil can be ignored. A fitting deviation relationship is sufficient, and subsequent foreign body detection using the deviation relationship can also ensure the accuracy of the foreign body detection results.
  • the process of obtaining the deviation relationship by the wireless charging device described above is a preparatory process for foreign object detection.
  • the above four fitting vertical relationships can be used, that is, the controller, which is specifically used to obtain the vertical relationship according to the resonant frequency of the wireless charging device and the electronic device at the current position or the self-inductance of the transmitting coil.
  • Q threshold and AC impedance That is, using f or L1 to obtain the Q value threshold and AC impedance for foreign object detection through the fitted vertical relationship. Because f and L1 can be converted, there is a conversion relationship, so f can also be used, and L1 can also be used.
  • the wireless charging device provided by the embodiment of the present application can fit the deviation relationship of the whole space according to the parameters of the wireless charging device and the electronic device, so as to realize the linearization process of the Q value and the relative position of the whole space, and it is not necessary to store the Q value and the whole space. corresponding data in the space.
  • the deviation relationship depends on the parameters sent by the electronic device because it is necessary to use the parameters of the electronic device.
  • the parameters of the electronic device sent to the wireless charging device may be different. Therefore, for different electronic devices, the fitting deviation relationship of the wireless charging device may be different. Therefore, the wireless charging device provided in the embodiment of the present application can realize For the universality of different electronic devices, that is, the fitted deviation relationship realizes the normalization of different electronic devices.
  • the wireless charging device does not need to store different parameters corresponding to different electronic devices, and directly uses the electronic device parameters sent by the corresponding electronic device to perform fitting, which can characterize the characteristics of the electronic device, so that the fitted deviation relationship can represent the wireless charging.
  • the second and second fitting methods use the pre-stored coupling parameters in the parameters of the electronic equipment, and the horizontal relationship obtained by using the pre-stored coupling parameters will be more accurate.
  • the impedance is adjusted, a more accurate Q value threshold and AC impedance can be obtained, thereby improving the accuracy of wireless charging foreign object detection.
  • the above methods of fitting the deviation relationship are suitable for various types of wireless charging equipment, such as wireless charging equipment with automatic alignment function, wireless charging equipment with mechanical card position function, and magnetic suction alignment. Functional wireless charging device.
  • the above embodiment only describes the use of wireless charging device parameters and electronic device parameters to fit the deviation relationship of the Q value relative to the entire position space.
  • the following describes how to use the current position to obtain the Q value threshold through the deviation relationship under the condition that the deviation relationship has been obtained. the process of.
  • the current position can include a horizontal relative position and a vertical relative position, which can be obtained according to the monotonic relationship between L1 and the vertical relative position and the monotonic relationship between the coupling parameter and the horizontal relative position.
  • Several implementations of obtaining the coupling parameter are described below. Way.
  • the coupling parameters used in fitting the deviation relationship above are included in the parameters of the electronic device, that is, the coupling parameters pre-stored by the electronic device.
  • the following describes the wireless charging device when the electronic device is in place. When the electronic equipment is coupled, the coupling parameters obtained by the online test.
  • This embodiment is applicable to wireless charging devices that do not have an automatic alignment function, and can also be applied to wireless charging devices that have an automatic alignment function.
  • the transmitting coil can be automatically displaced so as to be aligned with the receiving coil in the electronic device.
  • This embodiment introduces the specific foreign object detection process.
  • the self-inductance L1 of the transmitting coil and the coupling parameters between the wireless charging device and the electronic device can be obtained online.
  • the coupling parameters include: coupling coefficient k and mutual inductance M, where k and M both represent the coupling relationship between the wireless charging device and the electronic device.
  • the controller obtains the Q value threshold corresponding to the current relative position of the wireless charging device and the electronic device through the deviation relationship according to f or L1, and performs the Q value foreign object detection according to the Q value threshold corresponding to the current relative position; obtains according to the Q value threshold corresponding to the current relative position.
  • the AC impedance of the current relative position, and the Ploss foreign object detection is performed according to the AC impedance of the current relative position.
  • the Q value threshold and the AC impedance can be obtained according to the vertical relationship obtained by fitting according to the resonant frequency f of the online test or the self-inductance L of the transmitting coil.
  • the controller can obtain the Q value threshold and the AC impedance through the vertical relationship according to the resonant frequency f of the wireless charging device and the electronic device at the current position or the self-inductance L1 of the transmitting coil.
  • the following describes the process of obtaining the self-inductance L1 and f of the transmitting coil by the wireless charging device.
  • FIG. 7 is a schematic diagram of the relationship between the self-inductance L1 of the transmitting coil and the relative position according to the embodiment of the present application.
  • the abscissa is the horizontal relative position (unit: mm), and the ordinate is the vertical relative position (unit: mm).
  • the curves I1-I4 in the figure are the equipotential lines with the self-inductances of the transmitting coil being 6.8uH, 7.2uH, 7.6uH and 8.0uH respectively.
  • the self-inductance of the transmitting coil changes little with the horizontal relative position, and changes greatly with the vertical relative position. Therefore, the vertical relative position can be obtained through the self-inductance of the transmitting coil.
  • the controller 32 is further configured to obtain the self-inductance of the transmitting coil according to the resonant frequency of the resonant network at the transmitting end and the resonant capacitance of the resonant network at the transmitting end.
  • the self-inductance L1 of the transmitting coil can be obtained by the following formula:
  • C1 is the capacitance of the resonant network and is known, such as pre-existing in the wireless charging device
  • L1 is the self-inductance of the transmitting coil
  • f is the resonant frequency
  • the controller 32 turns off S1 and turns on S2 after judging that the full-bridge inverter circuit reaches a stable state.
  • the energy stored in C1 will be released in the resonant circuit formed by L1, C1 and the loop formed by S2 and S4.
  • the voltage oscillation curve can be obtained, and the resonant frequency f can be obtained through the voltage oscillation curve. .
  • the vertical relative position corresponding to the self-inductance can be obtained through the monotonic relationship corresponding to FIG. 7 . Since the vertical relationship obtained by fitting represents the relationship between the Q value threshold and the vertical relative position, the vertical relative position obtained by L1 can obtain the corresponding Q value threshold through the vertical relationship.
  • the vertical relationship directly includes the corresponding relationship between L1 and the Q value threshold, or directly includes the corresponding relationship between f and the Q value threshold. According to the f or L1 of the online test, the corresponding vertical relationship can be obtained directly by looking up the fitted vertical relationship. The Q value threshold, and then the AC impedance is obtained.
  • the above is a process of obtaining the Q value threshold using the vertical relationship.
  • the following describes the process of obtaining the Q value threshold when the deviation relationship includes a horizontal relationship and a vertical relationship. It should be understood that the AC impedance can be obtained after obtaining the Q value threshold. .
  • the controller is also used to obtain the coupling parameters and the self-inductance L1 of the transmitting coil in the coupling state of the wireless charging device and the electronic device;
  • the coupling parameters in the coupling state include at least one of the following: coupling coefficient and mutual inductance; according to the coupling in the coupling state
  • the Q value threshold and AC impedance are obtained through the deviation relationship between the parameters and L1;
  • the coupling parameter in the coupled state has a monotonic relationship with the horizontal relationship, and L1 has a monotonic relationship with the vertical relationship.
  • the controller is also used to receive the self-inductance L2 of the receiving coil in the coupled state sent by the electronic device; according to the current of the transmitting coil, the self-inductance L1 of the transmitting coil in the coupled state, the L2 and the corresponding rectified voltage of the receiving coil get coupling parameters;
  • the controller After the controller obtains the coupling parameters, the controller obtains the Q value threshold and the AC impedance through the deviation relationship according to the coupling parameters and the L1.
  • the controller is also used to receive the self-inductance L20 of the receiving coil in the uncoupled state sent by the electronic device; obtain the self-inductance L1 of the transmitting coil in the coupled state, the self-inductance L10 of the transmitting coil in the uncoupled state, and the L20 in the coupled state.
  • the self-inductance L2 of the receiving coil the coupling parameter is obtained according to the L1, the L2 and the rectified voltage corresponding to the receiving coil;
  • the controller After the controller obtains the coupling parameters, the controller obtains the Q value threshold and the AC impedance through the deviation relationship according to the coupling parameters and the L1.
  • the parameters of the electronic device may further include: the self-inductance L20 of the receiving coil in the uncoupled state or the self-inductance L2 of the receiving coil in the coupled state.
  • the controller 32 can obtain L2 according to L20.
  • the controller 32 is further configured to obtain the self-inductance L2 of the receiving coil in the coupled state according to L20.
  • the controller 32 can obtain the self-inductance L2 of the receiving coil in the coupled state according to the self-inductance L10 of the transmitting coil in the uncoupled state, the self-inductance L1 and L20 of the transmitting coil in the coupled state and a preset proportional relationship.
  • the receiver does not need to obtain L2, but only obtains L20.
  • the controller is also used to receive the self-inductance L3 of the auxiliary coil in the coupling state sent by the electronic device; according to the current of the transmitting coil, the self-inductance L1 of the transmitting coil in the coupling state, the L3 and the rectified voltage corresponding to the auxiliary coil get coupling parameters;
  • the controller After the controller obtains the coupling parameters, the controller obtains the Q value threshold and the AC impedance through the deviation relationship according to the coupling parameters and the L1.
  • the controller is also used to receive the self-inductance L30 of the auxiliary coil in the uncoupled state sent by the electronic device; obtain the self-inductance L1 of the transmitting coil in the coupled state, the self-inductance L10 of the transmitting coil in the uncoupled state, and the L30 in the coupled state.
  • the self-inductance L3 of the auxiliary coil the coupling parameter is obtained according to the rectified voltage corresponding to the L1, the L3 and the auxiliary coil;
  • the controller After the controller obtains the coupling parameters, the controller obtains the Q value threshold and the AC impedance through the deviation relationship according to the coupling parameters and the L1.
  • the electronic equipment parameters also include: the self-inductance L3 of the auxiliary coil in the coupled state or the fourth case, that is, the electronic equipment parameters also include: the self-inductance L30 of the auxiliary coil in the uncoupled state; the controller is also used for The self-inductance L3 of the auxiliary coil in the coupled state is obtained according to the self-inductance of the transmitting coil and the L30; generally, there is a preset proportional relationship between the self-inductance of the transmitting coil and the self-inductance of the auxiliary coil.
  • the controller can obtain the self-inductance L3 of the auxiliary coil in the coupled state according to the self-inductance L10 of the transmitting coil in the uncoupled state, the self-inductance L1 and L30 of the transmitting coil in the coupled state and a preset proportional relationship.
  • the receiving end does not need to obtain L3, that is, it can obtain L30.
  • the above four methods for obtaining coupling parameters are all obtained online, while the pre-stored coupling parameters included in the electronic device parameters in the first embodiment of the wireless charging device are pre-stored by the electronic device, for example, by a mobile phone.
  • the above describes the method for obtaining the coupling parameters.
  • the electronic device includes the auxiliary coil, the coupling parameters between the transmitting coil and the auxiliary coil can be obtained, and the coupling parameters between the transmitting coil and the receiving coil can also be obtained.
  • the electronic device has no auxiliary coil, only the coupling parameters between the transmitting coil and the receiving coil can be obtained.
  • this figure is a schematic diagram of the relationship between the coupling coefficient k and the relative position according to the embodiment of the present application.
  • the abscissa is the horizontal relative position (unit: mm)
  • the ordinate is the vertical relative position (unit: mm)
  • the dotted line L and dotted line K in the figure are the self-inductance of the transmitting coil and the transmitting coil obtained when the same relative position is obtained. and the coupling coefficient between the receiving coil.
  • the coupling coefficient between the transmitting coil and the receiving coil varies little with the vertical relative position, and greatly varies with the horizontal relative position.
  • the coupling coefficient between the transmitting coil and the receiving coil is negatively correlated with the horizontal relative position, that is, the larger the horizontal relative position is, the smaller the coupling coefficient between the transmitting coil and the receiving coil is. Therefore, the horizontal relative position can be obtained by obtaining the coupling coefficient between the transmitting coil and the receiving coil.
  • FIG. 9 is a schematic diagram of the relationship between the mutual inductance M and the relative position according to the embodiment of the present application.
  • the abscissa is the horizontal relative position (unit: mm), and the ordinate is the vertical relative position (unit: mm). It can be seen from FIG. 9 that the coil mutual inductance between the transmitting coil and the receiving coil varies little with the vertical relative position, and greatly varies with the horizontal relative position.
  • the coil mutual inductance between the transmitting coil and the receiving coil is negatively correlated with the horizontal relative position, that is, the greater the horizontal relative position, the smaller the coil mutual inductance between the transmitting coil and the receiving coil. Therefore, the horizontal relative position can be obtained by obtaining the coil mutual inductance between the transmitting coil and the receiving coil.
  • the vertical relative position is obtained according to L1 above, and the horizontal relative position is obtained according to k or M. Therefore, the corresponding Q value threshold can be obtained according to the deviation relationship between the vertical relative position and the horizontal relative position.
  • the corresponding Q value can be uniquely determined.
  • the coupling coefficient between the transmitting coil and the receiving coil can be obtained by the following formula (2):
  • L1 is the self-inductance of the transmitting coil
  • L2 is the self-inductance of the receiving coil
  • ⁇ is the operating frequency and known
  • the receiving end of the electronic device is in the empty state Load state, measure the rectified voltage Vrect, and the current I1 of the transmitting coil at this time.
  • the mutual inductance M between the transmitting coil and the receiving coil can be obtained by the following formula (3):
  • V rect is the DC voltage output by the rectifier circuit at the receiving end
  • I1 is the current of the transmitting coil
  • ⁇ is the operating frequency and is known
  • ⁇ is the coefficient and can be obtained through experiments.
  • the relative position can be obtained by using the coupling parameters between the auxiliary coil and the transmitting coil, or the relative position can be obtained by using the coupling parameters between the receiving coil and the transmitting coil, where the coupling
  • the parameters include k or M, that is, k can be used, or M can be used. Both k and M can represent the coupling relationship between the transmitting end and the receiving end. Moreover, both k and M have a monotonic relationship with the horizontal relative position.
  • this figure is a schematic diagram of a wireless charging system provided by an embodiment of the present application.
  • the electronic device includes a receiving coil L2, an auxiliary coil L3, a first rectifier 21a and a second rectifier 21b.
  • the first end of L2 is connected to the positive input end of the first rectifier 21a through C2, and the second end of L2 is connected to the negative input of the first rectifier 21a. end.
  • the output end of the first rectifier 21a is used to connect to the rear-stage charging circuit, and the rear-stage charging circuit is used to charge the battery in the electronic device.
  • L2 and C2 are connected in series to the input end of the first rectifier 21a.
  • the auxiliary coil L3 and the capacitor C3 are connected in series to the input end of the second rectifier 21b.
  • the controller controls the full-bridge inverter circuit at the transmitting end to be in an inverting state, controls the receiving end to be in a no-load state, and obtains the DC output voltage of the auxiliary coil and the current of the transmitting coil, according to the current of the transmitting coil and the DC output voltage of the auxiliary coil.
  • the coupling coefficient in at least one parameter obtained from the operating frequency, the self-inductance of the transmitting coil and the self-inductance of the auxiliary coil, the coupling coefficient between the transmitting coil and the auxiliary coil can be obtained by the following calculation formula (4):
  • V ac3 is the DC output voltage of the auxiliary coil
  • I 1 is the current of the transmitting coil
  • ⁇ is the operating frequency and is known
  • L1 is the self-inductance of the transmitting coil
  • L3 is the self-inductance of the auxiliary coil.
  • the controller 200 obtains the coupling coefficient between the transmitting coil and the auxiliary coil
  • the coil mutual inductance in at least one parameter is obtained according to the corresponding transmitting coil current when the receiving end is in the no-load state, the DC output voltage of the auxiliary coil, and the operating frequency
  • the coil mutual inductance M 2 between the transmitting coil and the auxiliary coil can be obtained by the following formula (5):
  • V ac3 is the DC output voltage of the auxiliary coil
  • I1 is the current of the transmitting coil
  • ⁇ is the operating frequency and is known.
  • ⁇ can be measured through experiments, and those skilled in the art can also modify the value of ⁇ in order to further improve the accuracy of detecting the coupling coefficient.
  • inverter circuit at the transmitting end in FIG. 6 is introduced by taking a full-bridge inverter circuit as an example.
  • an embodiment of the present application provides a circuit detection circuit.
  • FIG. 11 is a circuit diagram of a current detection circuit of a transmitting coil provided by an embodiment of the present application.
  • the wireless charging device provided in this embodiment further includes: a current detection circuit of the transmitting coil;
  • the current detection circuit is used to detect the voltage difference between the two ends of the resonant capacitor; for example, the voltage of the first end and the voltage of the second end of the resonant circuit are detected, and the difference between the voltage of the first end and the voltage of the second end is obtained, that is Voltage difference.
  • the controller is used to obtain the current of the transmitting coil according to the voltage difference.
  • the current detection circuit includes: a first voltage detection circuit 1001, a second voltage detection circuit 1002 and a differential circuit 1003;
  • the first voltage detection circuit 1001 is used to detect the first voltage of the first terminal of the resonant capacitor C1, divide the first voltage and send it to the first input terminal of the differential circuit 1003;
  • the second voltage detection circuit 1002 is used to detect the second voltage of the second terminal of the resonant capacitor C1, divide the second voltage and send it to the second input terminal of the differential circuit 1003;
  • the differential circuit 1003 is configured to obtain a differential result between the voltage input at the first input terminal and the voltage input at the second input terminal;
  • the controller 32 is configured to obtain the current of the transmitting coil L1 according to the difference result.
  • the inverter circuit can also be implemented by using a half-bridge circuit.
  • the following describes the process of obtaining the current of the transmitting coil corresponding to the half-bridge circuit.
  • FIG. 12 is another circuit diagram for detecting the current of the transmitting coil provided by the embodiment of the present application.
  • the current detection circuit of the transmitting coil corresponding to the half-bridge inverter circuit provided in this embodiment includes: a voltage divider circuit 1101 and a proportional amplifier circuit 1102;
  • the voltage divider circuit 1101 detects the voltage at one end of the resonant capacitor C1, divides the voltage and sends it to the input end of the proportional amplifier circuit 1102;
  • the proportional amplifier circuit 1102 is used for proportionally amplifying the input voltage and then sending it to the controller 32 .
  • the inverter circuit corresponding to FIG. 12 is a half-bridge circuit, the voltage at one end of the resonant capacitor C1 can be detected, and it is not necessary to detect the voltage at both ends to perform a differential.
  • the controller 32 in FIG. 11 and FIG. 12 can have its own analog-to-digital conversion function, that is, the voltage of the analog signal is directly input to the pins of the controller 32.
  • a first-stage analog-to-digital converter can also be connected before the pins of the controller 32 , and the analog-to-digital converter converts the analog signals into digital signals, and then sends them to the pins of the controller 32 .
  • the power loss is the power difference between the transmit power and the receive power, which can be calculated by the following formula:
  • P loss is the power loss
  • P tx is the transmit power
  • the transmit power is the magnetic field energy emitted by the transmitter
  • P rx is the receive power
  • the receive power is the magnetic field energy received by the receiver of the electronic device.
  • the transmit power P tx can be calculated by the following formula (6):
  • Pin is the input power of the transmitting end
  • P tx loss is the power loss of the transmitting end, including the loss of the circuit of the transmitting end and the loss of the transmitting coil.
  • the received power P rx can be calculated by the following formula:
  • P out is the output power of the receiving end
  • P rx loss is the power loss of the receiving end, including the loss of the circuit of the receiving end and the loss of the receiving coil.
  • the method provided by the embodiment of the present application is to introduce the AC impedance determined according to the above fitting deviation relationship into the calculation of P tx loss and P rx loss , thereby making the calculation results of P tx and P rx more accurate, thereby making P loss More accurate, improve the accuracy of Ploss foreign object detection, and can support higher power wireless charging.
  • the power loss of the wireless charging device can be expressed as the following formula (9):
  • Vin is the bus voltage of the inverter circuit
  • TxACR refers to the AC impedance ACR of the transmitting coil corresponding to the transmitting coil and the receiving coil at a certain relative position
  • I1 is the current of the transmitting coil
  • the above formulas (10) and (11) are ways to obtain the power loss of the transmitting end. It can be understood that the power loss P rx loss of the receiving end can also be obtained by referring to the above formula corresponding to the transmitting end. For example, when actually obtained, the state of the receiving end working at the transmitting end can be controlled, and each coefficient corresponding to the above formula can be obtained by pre-testing.
  • the embodiment of the present application also provides another method for detecting foreign objects in Ploss, specifically using k and AC impedance TxACR to detect foreign objects, which will be described in detail below.
  • the Ploss foreign object detection can be further performed according to the AC impedance and the coupling coefficient k of the online test.
  • k is the coupling coefficient between the transmitting coil and the receiving coil
  • f(k) can be a univariate linear function about the coupling coefficient k, or can be a univariate quadratic function about the coupling coefficient k; the coefficients of the above-mentioned univariate linear function and univariate quadratic function can be obtained through experiments in advance.
  • the coefficient d corresponding to the current coupling coefficient k can be accurately calculated online, thereby further improving the calculation accuracy of P tx loss and P rx loss .
  • the calculation of P rx loss at the receiving end is similar to that at the transmitting end.
  • the receiving end can be controlled to work in the transmitting end state, and each coefficient in the above formula can be measured in advance.
  • the power consumption of the transmitter accounts for the main proportion of the power consumption of the wireless charging system. Therefore, in actual products, generally only the power consumption of the transmitter can be used to calculate P tx loss using the above precise algorithm; the receiver does not need to use The exact algorithm described above computes P rx loss . It should be understood that the precise algorithm for the power consumption of the receiving end is similar to the precise algorithm for the power consumption of the transmitting end, as follows:
  • Vout is the bus voltage of the rectifier circuit
  • RxACR is the AC impedance ACR of the receiving coil when the transmitting coil and the receiving coil are in a certain relative position
  • I2 is the current of the receiving coil
  • the coupling coefficient k is the coupling coefficient between the transmitting coil and the receiving coil
  • the receiver can use the following simple formula:
  • the RxACR in the uncoupled state is the ACR of the receiving coil when the receiving coil is placed alone and far enough away from the transmitting coil, that is, the ACR of the corresponding receiving coil when the transmitting coil and the receiving coil are not coupled.
  • the Ploss foreign object detection method provided in the embodiment of the present application in addition to using the AC impedance, also adds the coupling coefficient k, that is, when detecting foreign objects, the power loss is obtained by using the AC impedance and the function of the coupling coefficient. Obtained, after adding the coupling coefficient, the calculated power loss can be made more accurate, so that it can be applied to the foreign object detection of higher power wireless charging.
  • the above various ways of obtaining coupling parameters are applicable to various types of wireless charging devices, and foreign object detection using the AC impedance and the coupling parameters of the online test is also applicable to various types of wireless charging devices.
  • a wireless charging device with an automatic alignment function is also applicable to a wireless charging device with a mechanical card position function, as well as a wireless charging device with a magnetic suction alignment function.
  • the technical solutions provided by the above embodiments can be applied to wireless charging devices with automatic alignment function, and can also be applied to wireless charging devices without automatic alignment function.
  • the wireless charging device can be a wireless charging device with automatic alignment, that is, the controller of the wireless charging device can control the movement of the transmitting coil through the horizontal relative position, so that it can automatically achieve alignment with the receiving coil.
  • the wireless charging device may also not have the automatic alignment function, that is, the alignment can be achieved by mechanical clamping or magnetic suction alignment.
  • this figure is a schematic diagram of another wireless charging device provided by an embodiment of the present application.
  • the wireless charging device provided in this embodiment further includes an alignment mechanism 33 .
  • the controller 32 controls the alignment mechanism 33 according to the moving direction of the transmitting coil to drive the transmitting coil to move along the moving direction.
  • An implementation manner of the alignment mechanism is that the alignment mechanism at least includes: a first motor, a second motor, a first guide rail and a second guide rail;
  • the first guide rail and the second guide rail are perpendicular to each other;
  • a first motor for driving the transmitting coil to move along the first guide rail
  • a second motor for driving the transmitting coil to move along the second guide rail
  • the controller is used for controlling the first motor and the second motor to move the transmitting coil along the moving direction.
  • this figure is a schematic diagram of an alignment structure provided by an embodiment of the present application.
  • x and y respectively represent two mutually perpendicular directions on the horizontal plane.
  • x represents the horizontal direction
  • y represents the direction perpendicular to the horizontal direction
  • the unit is millimeters.
  • the transmitting coil and the receiving coil are located in the non-communicable area, only the self-inductance L1 of the transmitting coil can be used to judge the relative position between the transmitting coil and the receiving coil.
  • the self-inductance L1 of the transmitting coil changes accordingly, and is generally on the same horizontal plane.
  • the self-inductance L1 of the transmitting coil changes with the position deviation. For example, when the coordinates of x and y are both 0, the corresponding L1 is 7.8uH, and when both x and y are 5mm, the corresponding L1 is 7.65uH, that is, the greater the position deviation, the greater the L1. Small, that is, L1 has a negative correlation with the position deviation.
  • this figure is a schematic diagram of the alignment principle of a transmitting coil provided by an embodiment of the present application.
  • the controller in the wireless charging device provided in this embodiment is further configured to obtain the self-inductance of the transmitting coils at two different positions and at least one of the following coupling parameters, where the coupling parameters include: coupling coefficient and mutual inductance;
  • the self-inductance of the transmitting coil and the at least one coupling parameter determine the horizontal relative position and the vertical relative position between the transmitting coil and the receiving coil, and the transmitting coil is moved according to the horizontal relative position to make the transmitting coil The coil is aligned with the receiving coil.
  • the self-inductance of the transmitting coil has a first monotonic relationship with the vertical relative position, and the at least one coupling parameter has a second monotonic relationship with the horizontal relative position.
  • the at least one coupling parameter has a second monotonic relationship with the horizontal relative position.
  • the self-inductance of the transmitting coil and the coupling coefficient k between the transmitting coil and the receiving coil are measured as examples for description below.
  • the coupling coefficient between the transmitting coil and the auxiliary coil can also be measured.
  • the coupling coefficients can be replaced by the mutual inductance M.
  • the position of the receiving coil can be determined by measuring the self-inductance L1 and the coupling coefficient k of the transmitting coils at two different positions. The following description will be made with reference to FIG. 15 .
  • the two positions measured are divided into O1 and O2, that is, the center of the transmit coil is at O1, and then moved to O2.
  • the self-inductance L1 and coupling coefficient k of the transmitting coil are obtained, and the horizontal relative position and vertical relative position between the transmitting coil and the receiving coil are obtained according to L1 and k measured at point O1.
  • the radial distance between the transmitting coil at O1 and the transmitting coil is obtained as r1 according to the horizontal relative position.
  • one of the two points where O1 is a circle whose center is r1 is a radius and O2 is a circle whose center is r2 is a radius intersect is the center of the receiving coil, that is, RX(A) or RX(B).
  • the controller of the wireless charging device is specifically used to obtain two horizontal relative positions (r1 and r2) corresponding to two different positions (O1 and O2) which are the first circle and the second circle of the radius respectively, and obtain the first circle and the second circle of the radius.
  • the intersection of the circumference and the second circumference, ie RX(A) or RX(B), controls the alignment of the transmit coil to the intersection.
  • the controller needs to control the transmitting coil to move, and the coupling coefficient can be obtained during the movement. For example, according to the changing trend of the coupling coefficient, the receiving coil can be judged.
  • the center corresponds to RX(A), or RX(B).
  • the controller is also used to move the transmitting coil to a third position, which is different from two different positions (that is, the third position can be different from O1 and O2); obtain at least one of the following parameters in the moving process, according to at least The change trend of one parameter determines the cross point where the transmitting coil is aligned; wherein, at least one parameter includes: coupling parameter, charging efficiency, self-inductance of the transmitting coil, current of the transmitting coil and output of the receiving end Voltage. Since at least one of the above parameters has a monotonic relationship with the horizontal relative position, the change trend of any one or more of the above parameters can be obtained during the movement process. According to the change trend and the monotonic relationship, the center of the receiving coil is determined as RX(A ), or RX(B).
  • the above parameters can be measured while moving, or it can be moved to a fixed position and then measured, which is not specifically limited in the embodiment of this application.
  • the fewer the measured positions the fewer the parameters.
  • the simplest one is to measure the parameters at three different positions to determine the center position of the receiver coil. After the controller obtains the center position of the receiving coil, it can control the transmitting coil to move, so that the transmitting coil and the receiving coil are aligned.
  • the moving position may make the two circles corresponding to r1 and r2 tangent, that is, there is only one intersection point between the two circles.
  • the point is the center of the receiver coil.
  • the alignment of the transmitting coil and the receiving coil are different. Positional deviation may continue to exist. Therefore, it is necessary to measure L1 and k after alignment again, and obtain the horizontal relative position and vertical relative position between the aligned transmitting coil and receiving coil according to L1 and k. According to the horizontal relative position The Q value threshold and the AC impedance are obtained by fitting the deviation relationship with the vertical relative position, and then the Q value threshold is used to detect the Q value foreign body, and the AC impedance is used to detect the Ploss foreign body.
  • the horizontal deviation can be ignored, and the corresponding Q can be obtained only according to the fitted vertical relationship. value threshold and AC impedance.
  • the controller can control the transmitting coil to move back to the initial position. , it is necessary to record the moving trajectory of the transmitting coil or record the final position coordinates of the transmitting coil, and move the transmitting coil back to the initial position according to the moving trajectory or the final position coordinates of the transmitting coil.
  • the initial position of the transmitting coil is a known parameter.
  • the controller is used to control the transmitting coil to move to a fourth position, and the fourth position is not on the same straight line as the first position and the second position, that is, the three points are not on the same straight line; obtaining the fourth position
  • the self-inductance and coupling parameters of the transmitting coil corresponding to the position; the horizontal relative position and the vertical relative position are determined according to the self-inductance and coupling parameters of the transmitting coil corresponding to the fourth position, and the third circle is determined according to the horizontal relative position, and the transmitting coil is controlled to move to The common point of the third circle and the intersection.
  • this figure is a schematic diagram of a wireless charging device with a mechanical card position provided by an embodiment of the present application.
  • the wireless charging device 02 is provided with a card position 02a. It should be understood that the embodiment of the present application does not specifically limit the specific implementation form of the card position 02a, and the card position 02a mainly serves as a position limiter.
  • the card position 02a can be a protrusion or a groove, as long as the electronic device 01 can be fixed.
  • the card position 02a fixes the electronic device 02 to prevent the electronic device 02 from moving relative to the wireless charging device 02, thereby ensuring the relative position between the electronic device 01 and the wireless charging device 02 , to achieve high-efficiency charging.
  • the wireless charging device may have a magnetic suction alignment function.
  • this figure is a schematic diagram of a wireless charging device with magnetic suction alignment provided by an embodiment of the present application.
  • the wireless charging device 02 is provided with a magnet 02b.
  • the embodiment of the present application does not specifically limit the specific position of the magnet 02b.
  • the magnet 02b can be effectively connected to the magnet in the electronic device 01. Therefore, the electronic device 01 can be adsorbed at a suitable position of the wireless charging device 02 to help the alignment between the wireless charging device 02 and the electronic device 01, thereby improving the efficiency of wireless charging.
  • the controller does not have to automatically control the movement of the transmitting coil, but can detect the alignment of the transmitting coil and the receiving coil.
  • the controller is also used to obtain the Q value threshold and the AC impedance according to the self-inductance of the transmitting coil through the deviation relationship obtained by the above fitting; according to the Q value threshold Perform Q-value foreign body detection, and Ploss foreign body detection according to AC impedance and coupling parameters. Since there is no horizontal deviation after alignment, only vertical deviation exists, and the Q value threshold and AC impedance can also be obtained only by using the fitted vertical relationship.
  • the embodiments of the present application further provide a wireless charging base for wirelessly charging an electronic device, for example, the electronic device is a mobile phone or a wearable device.
  • the wireless charging base is placed horizontally on the desktop, and the mobile phone can be placed horizontally on the wireless charging base. Therefore, the electromagnetic field coupling between the transmitting coil and the receiving coil realizes the transmission of energy and completes the wireless charging of the mobile phone.
  • the wireless charging base provided in this embodiment is used for wirelessly charging electronic devices, including: a power interface, a resonance network, an inverter circuit, a controller, a transmitting coil chassis, and an alignment guide rail.
  • the wireless charging base is 02
  • the power interface of the wireless charging base 02 is connected to the adapter 40
  • the adapter 40 converts the commercial power into DC power and provides the wireless charging base 02 .
  • the power interface is used to connect the DC power transmitted by the adapter
  • the adapter is used to convert AC mains into DC power, and provide it to the power interface, for example, to convert AC 220V mains into DC power.
  • the resonant network includes a resonant capacitor and a transmitting coil
  • a transmitting coil chassis for placing the transmitting coil
  • the input end of the inverter circuit is used to connect the power interface, and the output end of the inverter circuit is used to connect to the resonance network;
  • the controller is configured to receive the electronic device parameters sent by the electronic device, and fit the deviation relationship between the Q value of the wireless charging device and the position space according to the wireless charging device parameters and the electronic device parameters, and the position space is The position space between the transmitting coil and the receiving coil of the electronic device; wherein the parameters of the electronic device include: the wireless charging device when at least one relative position between the transmitting coil and the receiving coil is free of foreign objects The Q1 value of the resonant network and the resonant frequency f1 of the resonant network; the parameters of the wireless charging device include: the initial Q value Q0 of the wireless charging device and the resonance when the wireless charging device and the electronic device are not coupled The initial resonant frequency f0 of the network.
  • the controller is further configured to perform foreign object detection according to the deviation relationship.
  • the wireless charging base provided in this embodiment can fit the deviation relationship of the Q value relative to the entire position space according to a limited number of wireless charging device parameters and electronic device parameters, that is, fitting a Q value similar to that represented in FIG. 5 relative to the horizontal relative Correspondence between position and vertical relative position. Therefore, the wireless charging device does not need to store all the data of the Q value and the horizontal relative position and the Q value and the vertical relative position of the entire position space, thereby greatly reducing the storage space.
  • the controller 32 uses the Q1 value and the resonant frequency f1 when there is no foreign matter in at least one relative position of the transmitting coil and the receiving coil, and the initial Q value Q0 and the initial resonant frequency f0 in the non-coupling state to obtain the deviation relationship of the Q value with respect to the entire position space. , after obtaining the deviation relationship of the Q value relative to the entire position space, the Q value corresponding to the current position can be obtained through the deviation relationship, so as to perform foreign object detection according to the Q value.
  • the corresponding AC impedance can be obtained from the Q value, that is, the deviation relationship of the AC impedance relative to the entire position space can be omitted, and the AC impedance can be converted by the Q value. , so as to perform Ploss foreign object detection according to the AC impedance.
  • the parameters of the electronic device may include the Q1 value and f1 of at least one relative position of the transmitting coil and the receiving coil, and may also include the Q1 value and f1 of at least two relative positions. It is understood that the more relative positions, the more corresponding parameters. , the more parameters are involved in the fitting, the more accurate the fitted deviation relationship will be. The following description will be given by taking as an example that the parameters of the electronic device include at least two relative positions. Where the electronic device parameter includes a relative position, reference may be made to the introduction of the wireless charging device in the above embodiment.
  • the electronics parameters include the following Q1 values and f1 for at least two relative positions between the transmit coil and the receive coil: Q11 and f11 in the first position, and Q12 and f12 in the second position.
  • the deviation relationship includes: a radial horizontal relationship between the transmitting coil and the receiving coil and a vertical relationship between a plane where the transmitting coil is located and a plane where the receiving coil is located.
  • the electronic device parameters also include: pre-stored coupling parameters when at least one relative position between the transmitting coil and the receiving coil is free of foreign objects; the pre-stored coupling parameters include at least one of the following: coupling coefficient and mutual inductance;
  • the controller fits the vertical relationship according to f0, Q0 and the Q1 value of at least one relative position and f1; fits the horizontal relationship according to the pre-stored coupling parameters and the Q1 value of at least one relative position; obtains the Q value threshold through the vertical relationship and the horizontal relationship and AC impedance.
  • a specific implementation manner of fitting the deviation relationship is that the deviation relationship includes: a vertical relationship and a horizontal relationship;
  • the electronic device parameters further include: pre-stored coupling parameters at the first position and pre-stored coupling parameters at the second position; the pre-stored coupling parameters include at least one of the following: coupling coefficient and mutual inductance;
  • a controller specifically configured to fit a horizontal relationship according to Q11, Q12, the pre-stored coupling parameters of the first position and the pre-stored coupling parameters of the second position;
  • the Q value threshold and the AC impedance are obtained through the vertical relationship and the horizontal relationship.
  • the coupling parameters detected online can be used to obtain the corresponding horizontal relative position through the deviation relationship, that is, the coupling parameter and the horizontal relationship are monotonic.
  • the coupling coefficient k of can obtain the corresponding horizontal relative position through the deviation relationship, and since the horizontal relative position has a monotonic relationship with the Q value, the corresponding Q value threshold can be obtained.
  • the Q value threshold can also be obtained directly according to the monotonicity of the relationship between k and the level, so the fitted horizontal relationship is the horizontal monotonic relationship between the Q value and the space.
  • the above fitted vertical relationship can be used. Since both the resonance frequency and the transmitting coil have a monotonic relationship with the vertical relative position, the controller can be based on the resonance of the wireless charging device and the electronic device at the current position.
  • the frequency or the self-inductance of the transmitting coil obtains the Q-value threshold and the AC impedance through a vertical relationship. That is, the resonant frequency f or the self-inductance L1 of the transmitting coil is used to obtain the Q value threshold and the AC impedance for foreign object detection through the fitted vertical relationship. Because f and L1 can be converted, there is a conversion relationship, so f can also be used, and L1 can also be used.
  • the controller can perform Ploss foreign object detection according to the AC impedance and the coupling parameters in the coupling state of the online test. Among them, there is a monotonic relationship between the coupling parameter and the horizontal relative position. Therefore, by using the coupling parameter, the corresponding AC impedance can be accurately obtained through the horizontal relationship, thereby improving the accuracy of the calculated power loss.
  • the wireless charging base can further include: an alignment mechanism; the controller can control the alignment mechanism to drive the transmitting coil and the receiving coil to align.
  • an alignment mechanism can control the alignment mechanism to drive the transmitting coil and the receiving coil to align.
  • the wireless charging device may include a mechanical card position to achieve alignment.
  • the wireless charging device may also include magnetic suction alignment to achieve alignment. For both the mechanical card position and the magnetic suction alignment, reference may be made to the description of the above embodiments of the wireless charging device.
  • the alignment structure at least includes an alignment guide rail; the alignment guide rail includes at least: a first guide rail and a second guide rail whose projections on the horizontal plane are perpendicular to each other; and also includes: an electric drive part; an electric drive part for driving the transmitting coil along the first guide rail The guide rail and the second guide rail move; the controller is also used to control the electric drive part, and the electric drive part drives the transmitting coil to align with the receiving coil.
  • the wireless charging base can also have the function of automatic alignment, that is, the controller, and is also used to obtain the self-inductance of the transmitting coils at two different positions and at least one of the following coupling parameters.
  • the coupling parameters include: coupling coefficient and mutual inductance;
  • the self-inductance of the coil and at least one coupling parameter determine the horizontal relative position and the vertical relative position between the transmitting coil and the receiving coil, and move the transmitting coil according to the horizontal relative position, so that the transmitting coil and the receiving coil are aligned;
  • the self-inductance of the transmitting coil has a first monotonic relationship with the vertical relative position, and at least one coupling parameter has a second monotonic relationship with the horizontal relative position.
  • the wireless charging base may include an alignment mechanism corresponding to FIG. 13 and FIG. 14 , and the controller controls the alignment mechanism to align the transmitter coil and the receiver coil.
  • the embodiments of the present application further provide a foreign object detection method for wireless charging, which will be described in detail below with reference to the accompanying drawings.
  • Embodiment 1 of the foreign body detection method is a method for determining whether the foreign body detection method is a foreign body detection method.
  • FIG. 18 is a flowchart of a foreign object detection method for wireless charging provided by an embodiment of the present application.
  • the foreign object detection method for wireless charging is applied to a wireless charging device.
  • the wireless charging device includes: a resonant network and an inverter circuit; the resonant network includes a resonant capacitor and a transmitting coil; the input end of the inverter circuit is used to connect a DC power supply , the output of the inverter circuit is used to connect the resonant network;
  • the method includes the following steps:
  • S1601 Receive the electronic device parameters sent by the electronic device; the electronic device parameters include: the Q1 value and the resonant frequency f1 when there is no foreign matter in at least one relative position of the transmitting coil and the receiving coil;
  • the electronic device parameters are initial parameters pre-stored by the electronic device.
  • the electronic device is a mobile phone, which may be parameters that are pre-stored when the mobile phone leaves the factory.
  • the parameters of the electronic equipment include: Q1 value and resonance frequency f1 when there is no foreign matter in at least one relative position.
  • the at least one relative position refers to the relative position between the wireless charging device and the electronic device, generally based on the relative position between the transmitting coil and the receiving coil. For example, it can be a parameter corresponding to one relative position, or a parameter corresponding to two positions, or a parameter corresponding to multiple positions. It can be understood that the more relative positions, the more corresponding parameters, the The fitted deviation relationship is more accurate.
  • the Q1 value when there are no foreign objects in the two relative positions refers to the Q1 value measured by the mobile phone when the mobile phone is in two different positions relative to the wireless charger
  • the resonance frequency f1 when there are no foreign objects in the two positions refers to the mobile phone relative to the wireless charger.
  • the resonant frequency f1 of the resonant network of the wireless charger When the charger is in two different positions, the resonant frequency f1 of the resonant network of the wireless charger.
  • the wireless charging device parameters are parameters pre-stored by the wireless charging device, such as parameters pre-stored by the wireless charger.
  • the parameters of the wireless charging device include: the initial Q value Q0 and the initial resonant frequency f0 in the non-coupling state of the wireless charging device and the electronic device.
  • the non-coupling state means that the distance between the wireless charging device and the electronic device is relatively far, and there is no electromagnetic coupling. That is, for the wireless charger, Q0 and f0 of the wireless charger when the mobile phone is not detected.
  • S1602 Fit the deviation relationship of the Q value with respect to the position space according to the parameters of the electronic device and the parameters of the wireless charging device;
  • the parameters of the wireless charging device include: the initial Q value Q0 and the initial resonant frequency f0 in the uncoupled state of the wireless charging device and the electronic device;
  • the deviation relationship may be a linear function or a multiple function.
  • the embodiment of the present application does not specifically limit the fitting method. According to a plurality of known parameters, the deviation relationship of the Q value relative to the space can be fitted.
  • S1603 Obtain the Q value threshold according to the deviation relationship to perform the Q value foreign object detection, obtain the corresponding AC impedance according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil, and perform the Ploss foreign object detection according to the obtained AC impedance.
  • the controller 32 of the wireless charging device provided by the embodiment of the present application can fit the deviation relationship of the Q value relative to the entire position space according to a limited number of wireless charging device parameters and electronic device parameters, that is, fitting a Q value similar to that represented in FIG. 5 . Correspondence with respect to the horizontal relative position and the vertical relative position. Therefore, the wireless charging device does not need to store all the data of the Q value and the horizontal relative position and the Q value and the vertical relative position of the entire position space, thereby greatly reducing the storage space.
  • the controller 32 uses the Q1 value and the resonant frequency f1 when there is no foreign matter in at least one relative position, the initial Q value Q0 and the initial resonant frequency f0 in the non-coupling state to obtain the deviation relationship of the Q value relative to the entire position space, and obtain the relative Q value relative.
  • the Q value corresponding to the current position can be obtained through the deviation relationship, so as to perform foreign object detection according to the Q value. Since the Q value and the AC impedance of the transmitting coil have the relationship shown in formula (1), the corresponding AC impedance can be obtained from the Q value, that is, the deviation relationship of the AC impedance relative to the entire position space can be omitted without fitting. After passing the Q value, the AC impedance can be converted, so that the Ploss foreign object detection can be performed according to the AC impedance during the wireless charging process.
  • the deviation relationship fitted in the embodiment of the present application includes: the radial horizontal relationship between the transmitting coil and the receiving coil and the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located;
  • a vertical relationship is fitted according to f0, Q0, and the Q1 value and f1 in the electronic device parameters.
  • the fitted deviation relationship may only include a vertical relationship. Because when the transmitter coil in the wireless charging device can move, the transmitter coil can be controlled to move in alignment with the receiver coil. The vertical offset cannot be changed when the position of the electronic device and the wireless charging device is fixed.
  • Electronic device parameters include the following Q1 values and f1 for at least two relative positions between the transmitting coil and the receiving coil: Q11 and f11 in a first position, and Q12 and f12 in a second position.
  • the deviation relationship includes: the radial horizontal relationship between the transmitting coil and the receiving coil and the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located.
  • Fitting the deviation relationship between the Q value and the position space according to the parameters of the wireless charging device and the parameters of the electronic device specifically including:
  • the Q value threshold and the AC impedance are obtained through the horizontal relationship and the vertical relationship.
  • the deviation relationship includes: the radial horizontal relationship between the transmitting coil and the receiving coil and the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located.
  • the electronic device parameters further include: pre-stored coupling parameters when there is no foreign matter in the at least one position; the pre-stored coupling parameters include at least one of the following: coupling coefficient and mutual inductance;
  • Fitting the deviation relationship between the Q value and the position space according to the parameters of the wireless charging device and the parameters of the electronic device specifically including:
  • the obtaining of the Q value threshold and the AC impedance according to the deviation relationship specifically includes:
  • the Q value threshold is obtained through the vertical relationship and the horizontal relationship, and the corresponding AC impedance is obtained according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil.
  • Electronic device parameters include the following Q1 values and f1 for at least two relative positions between the transmitting coil and the receiving coil: Q11 and f11 in a first position, and Q12 and f12 in a second position.
  • the deviation relationship includes: the radial horizontal relationship between the transmitting coil and the receiving coil and the vertical relationship between the plane where the transmitting coil is located and the plane where the receiving coil is located.
  • the electronic device parameters also include: pre-stored coupling parameters at the first position and pre-stored coupling parameters at the second position; the pre-stored coupling parameters include at least one of the following: coupling coefficient and mutual inductance between the transmitting coil and the receiving coil;
  • Fitting the deviation relationship between the Q value and the position space according to the parameters of the wireless charging device and the parameters of the electronic device specifically including:
  • the Q value threshold is obtained through the vertical relationship and the horizontal relationship, and the corresponding AC impedance is obtained according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil .
  • the coupling parameters detected online can be used to obtain the corresponding horizontal relative position through the deviation relationship when the deviation relationship is used subsequently, that is, the coupling parameter and the horizontal relationship exist.
  • Monotonicity for example, using the coupling coefficient k of the online test to obtain the corresponding horizontal relative position through the deviation relationship, and because there is a monotonic relationship between the horizontal relative position and the Q value, the corresponding Q value threshold can be obtained.
  • the Q value threshold can also be obtained directly according to the monotonicity of the relationship between k and the level, so the fitted horizontal relationship is the horizontal monotonic relationship between the Q value and the space.
  • the deviation relationship includes: a vertical relationship; fitting the deviation relationship between the Q value and the position space according to the wireless charging device parameters and the electronic device parameters, specifically including:
  • the fourth type is only suitable for the situation that there is no deviation between the transmitting coil and the receiving coil in the horizontal direction, or the deviation is small and can be ignored, and only the vertical deviation can be fitted.
  • the horizontal deviation if the transmitter coil of the wireless charging device can be aligned, the foreign object can be judged after alignment.
  • the relationship between the Q value and the vertical direction can be accurately fitted.
  • This method is especially suitable for the case where the wireless charging device has an automatic alignment function, that is, the wireless charging device controls the movement of the transmitting coil. Realize the alignment with the receiving coil, so that the horizontal deviation between the transmitting coil and the receiving coil is small or negligible, and only the vertical deviation can be considered. Therefore, the Q value and Ploss foreign matter detection are carried out using the fitted vertical relationship. It can also ensure the accuracy of foreign body detection results.
  • the above four fitting vertical relationships can be used, that is, the controller, which is specifically used to obtain the vertical relationship according to the resonant frequency of the wireless charging device and the electronic device at the current position or the self-inductance of the transmitting coil.
  • Q threshold and AC impedance That is, using f or L1 to obtain the Q value threshold and AC impedance for foreign object detection through the fitted vertical relationship. Since f and L1 can be converted and there is a conversion relationship, f can also be used, and L1 can also be used.
  • FIG. 19 is a flowchart of another method for detecting foreign objects in wireless charging provided by an embodiment of the present application.
  • the electronic equipment parameters include: the following Q1 values and f1 at at least two relative positions of the transmitting coil and the receiving coil: Q11 and f11 at the first position, and Q12 and f12 at the second position; the electronic equipment parameters also include: The self-inductance L2 of the receiving coil in the coupled state;
  • the corresponding foreign body detection methods include:
  • S1701 Receive Q11 and f11 of the first position and Q12 and f12 of the second position sent by the electronic device;
  • S1703 Fit the vertical relationship according to the f0, the Q0, the Q11, and the f11; or, fit the vertical relationship according to the f0, the Q0, the Q12, and the f12 or, fitting the vertical relationship according to Q and f corresponding to at least one point in the Q0, the f0 and the horizontal relationship.
  • S1704 Obtain a Q value threshold according to a horizontal relationship and a vertical relationship, and obtain a corresponding AC impedance according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil.
  • S1705 Perform Q-value foreign object detection according to the Q-value threshold before the wireless charging device charges the electronic device, and perform Ploss foreign object detection according to the obtained AC impedance during the wireless charging device charging the electronic device.
  • the electronic device does not need to obtain the self-inductance L2 of the receiving coil in the coupled state, but only needs to obtain the self-inductance L20 of the receiving coil in the uncoupled state, and sends L20 to the wireless charging device or wireless charging base , L2 is obtained by wireless charging device according to L20.
  • the parameters of the electronic device include the self-inductance of the receiving coil.
  • the parameters of the electronic device may include the self-inductance of the auxiliary coil.
  • FIG. 20 is a flowchart of still another method for detecting foreign objects in wireless charging provided by an embodiment of the present application.
  • the parameters of the electronic device include Q1 values and f1 at at least two relative positions between the transmitting coil and the receiving coil: Q11 and f11 at the first position, and Q12 and f12 at the second position.
  • the deviation relationship includes: a vertical relationship and a horizontal relationship;
  • the electronic device parameters further include: the pre-stored coupling parameters of the first position and the pre-stored coupling parameters of the second position;
  • the pre-stored coupling parameters include at least one of the following: coupling coefficient and mutual inductance;
  • S1901 Receive Q11 and f11 of the first position and Q12 and f12 of the second position sent by the electronic device;
  • S1902 Fit the horizontal relationship according to Q11, Q12, the pre-stored coupling parameter of the first position, and the pre-stored coupling parameter of the second position; for example, the pre-stored coupling parameter is the coupling coefficient k.
  • S1903 Fit the vertical relationship according to the f0, the Q0, the Q11 and the f11; or, fit the vertical relationship according to the f0, the Q0, the Q12 and the f12 or, fitting the vertical relationship according to Q and f corresponding to at least one point in the Q0, the f0 and the horizontal relationship.
  • S1902 and S1903 are not in sequence, and may be performed simultaneously or sequentially, which is not specifically limited in the embodiments of the present application.
  • S1903 it is necessary to fit the horizontal relationship first, and then fit the vertical relationship according to the result of the horizontal relationship.
  • S1904 Obtain a Q value threshold according to a horizontal relationship and a vertical relationship, and obtain a corresponding AC impedance according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil.
  • S1905 Perform Q-value foreign object detection according to the Q-value threshold before the wireless charging device charges the electronic device, and perform Ploss according to the obtained AC impedance during the process of charging the electronic device by the wireless charging device Foreign body detection.
  • the electronic device parameters include Q1 and f1 of at least two relative positions, and the following describes the situation when the electronic device parameters include at least one position.
  • the parameters of the electronic device may also include: at least one coupling parameter when there is no foreign object in the relative position; the coupling parameter includes at least one of the following: coupling coefficient and mutual inductance between the transmitting coil and the receiving coil;
  • FIG. 21 is a flowchart of another method for detecting foreign objects in wireless charging provided by an embodiment of the present application.
  • the coupling parameters included in the parameters of the electronic equipment participate in the fitting of the horizontal relationship, because there is a monotonic relationship between the coupling parameters and the horizontal relative position.
  • S2004 Obtain a Q value threshold according to a horizontal relationship and a vertical relationship, and obtain a corresponding AC impedance according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil.
  • S2005 Perform Q-value foreign object detection according to the Q-value threshold before the wireless charging device charges the electronic device, and perform Ploss according to the obtained AC impedance during the process of charging the electronic device by the wireless charging device Foreign body detection.
  • the parameters of the electronic device may only include the parameters of one position, but since the parameters of the electronic device include the pre-stored coupling parameters, the horizontal relationship can also be accurately fitted by using the parameters of one position, because the pre-stored coupling parameters and the horizontal phase
  • the position has a monotonic relationship, and this embodiment can accurately fit the horizontal relationship by using the monotonic relationship.
  • the controller can obtain the Q value threshold and the AC impedance through the vertical relationship according to the resonant frequency of the wireless charging device and the electronic device at the current position or the self-inductance of the transmitting coil, and use the Q value threshold to perform the Q value threshold.
  • Value foreign body detection using AC impedance for Ploss foreign body detection.
  • the above methods of fitting the deviation relationship are applicable to various types of wireless charging equipment, such as wireless charging equipment with automatic alignment function, wireless charging equipment with mechanical card position function, and magnetic suction pair Bit-capable wireless charging device.
  • the following describes the method of detecting foreign objects when the transmitter coil and the receiver coil are not aligned.
  • FIG. 22 is a flowchart of a foreign object detection method provided by an embodiment of the present application.
  • S2201 Receive electronic device parameters sent by the electronic device
  • the parameters of the electronic device may be the various situations introduced in the second embodiment of the above method, which will not be repeated here.
  • S2202 Fitting to obtain a deviation relationship according to the parameters of the electronic device and the parameters of the wireless charging device;
  • S2203 Obtain the coupling parameter in the coupling state corresponding to the current relative position between the wireless charging device and the electronic device and the self-inductance L1 of the transmitting coil;
  • the coupling parameters may include coupling coefficient k or mutual inductance M.
  • the coupling parameter has a monotonic relationship with the horizontal relationship, and L1 has a monotonic relationship with the vertical relationship.
  • the coupling parameters are obtained from the online test of the wireless charging device, not from the electronic device parameters received from the electronic device, that is, not the coupling parameters pre-stored by the electronic device.
  • the coupling parameter is between the transmitting coil and the receiving coil, and the controller is also used to receive the self-inductance L2 of the receiving coil in the coupling state sent by the electronic device; according to the current of the transmitting coil, the coupling state Coupling parameters are obtained from the self-inductance L1 of the transmitting coil, the L2 and the corresponding rectified voltage of the receiving coil.
  • the coupling parameter is between the transmitting coil and the receiving coil, and the controller is also used to receive the self-inductance L20 of the receiving coil in the uncoupled state sent by the electronic device; according to the self-inductance L1 of the transmitting coil in the coupled state, the non-coupling
  • the self-inductance L10 and the L20 of the transmitting coil in the coupled state obtain the self-inductance L2 of the receiving coil in the coupled state
  • the coupling parameter is obtained according to the L1, the L2 and the rectified voltage corresponding to the receiving coil.
  • the coupling parameter is between the transmitting coil and the auxiliary coil, and the controller is also used to receive the self-inductance L3 of the auxiliary coil in the coupling state sent by the electronic device; according to the current of the transmitting coil and the self-inductance of the transmitting coil in the coupling state,
  • the coupling parameters are obtained from the rectified voltages corresponding to the inductor L1, the L3 and the auxiliary coil.
  • the coupling parameter is between the transmitting coil and the auxiliary coil, and the controller is also used to receive the self-inductance L30 of the auxiliary coil in the uncoupled state sent by the electronic device; according to the self-inductance L1 of the transmitting coil in the coupled state, the uncoupled state
  • the self-inductance L10 and the L30 of the lower transmitting coil obtain the self-inductance L3 of the auxiliary coil in the coupled state, and the coupling parameter is obtained according to the L1, the L3 and the rectified voltage corresponding to the auxiliary coil.
  • the parameters of the electronic device also include the self-inductance of the receiving coil in the coupled state or the receiving coil in the uncoupled state. Self-inductance of the coil.
  • the third and fourth types are between the transmitting coil and the auxiliary coil.
  • the parameters of the electronic device also include the self-inductance of the auxiliary coil in the coupled state or the self-inductance of the auxiliary coil in the uncoupled state.
  • the acquisition of the current of the transmitting coil used when the coupling parameter is obtained may refer to the methods described above in FIG. 11 and FIG. 12 , and details are not repeated here.
  • the current horizontal relative position is obtained according to the coupling coefficient
  • the current vertical relative position is obtained according to L1
  • the corresponding Q value threshold and AC impedance can be obtained according to the deviation relationship between the current horizontal relative position and the current vertical relative position.
  • the deviation relationship can be a single function or multiple functions, that is, the deviation relationship is a functional expression of the position deviation and the Q value. Therefore, when the position deviation is known, the corresponding Q value can be obtained according to the known function expression.
  • S2205 Perform Q-value foreign object detection according to the Q-value threshold, and perform Ploss foreign object detection according to the AC impedance and the coupling parameters in the coupling state obtained above.
  • the foreign object detection method provided in the embodiment of the present application can be applied to a wireless charging device that does not have an automatic alignment function. Since the wireless charging device is fitted to obtain the deviation relationship of the entire position space, even if there is a spatial position deviation between the transmitting coil and the receiving coil, The corresponding Q value threshold and AC impedance under the deviation can also be obtained, and then the foreign body detection can be performed, and the accuracy of the foreign body detection result can also be ensured.
  • FIG. 23 is a flowchart of the foreign object detection method with alignment provided by the embodiment of the present application.
  • This embodiment introduces the foreign object detection process when the wireless charging device has an automatic alignment function.
  • S2301 Receive electronic device parameters sent by the electronic device
  • the parameters of the electronic device may be the various situations introduced in the second embodiment of the above method, which will not be repeated here.
  • S2302 Fitting to obtain a deviation relationship according to the parameters of the electronic device and the parameters of the wireless charging device;
  • An implementation method is: the coupling parameter is between the transmitting coil and the receiving coil, according to the current of the transmitting coil, the self-inductance of the transmitting coil, the self-inductance of the receiving coil and the receiving coil.
  • the corresponding rectified voltage obtains the coupling parameter.
  • the coupling parameter is between the transmitting coil and the auxiliary coil, according to the current of the transmitting coil, the self-inductance of the transmitting coil, the self-inductance of the auxiliary coil and the auxiliary coil
  • the coupling parameter is obtained from the rectified voltage corresponding to the coil.
  • S2304 Determine the horizontal relative position and the vertical relative position between the transmitting coil and the receiving coil according to the self-inductance and coupling parameters of the transmitting coil;
  • S2305 Move the transmitting coil according to the horizontal relative position, so that the transmitting coil is aligned with the receiving coil;
  • the moving the transmitting coil according to the horizontal relative position to align the transmitting coil with the receiving coil specifically includes:
  • the at least one parameter includes: the coupling parameter, charging efficiency , the self-inductance of the transmitting coil, the current of the transmitting coil and the output voltage of the receiving end.
  • the self-inductance of the transmitting coil has a first monotonic relationship with the vertical relative position, and the at least one coupling parameter has a second monotonic relationship with the horizontal relative position.
  • S2306 Obtain a Q value threshold through the deviation relationship according to the self-inductance of the transmitting coil, and obtain a corresponding AC impedance according to the Q value threshold and the corresponding relationship between the Q value and the AC impedance of the transmitting coil;
  • the foreign object detection method provided by the embodiment of the present application can realize the fitting of the deviation relationship in the whole space, realize the linearization of the Q value, and realize the normalization of different electronic devices at the same time.
  • the wireless charging device has the function of automatic alignment. Since there may be a slight deviation after automatic alignment, the corresponding Q value threshold and AC impedance can be obtained according to the relative position after alignment through the deviation relationship. Then, the Q-value foreign body detection and Ploss foreign body detection after alignment are carried out to further ensure the accuracy of the foreign body detection results.
  • the horizontal deviation between the transmitting coil and the receiving coil is so small that it can be ignored, so it is not necessary to consider the influence of the horizontal deviation, only the influence of the vertical deviation can be considered, that is, in another implementation
  • the coupling parameters after alignment are obtained, and when the horizontal relative position after alignment is judged to be within the preset deviation range according to the coupling parameters, the vertical relative position after alignment is obtained according to the self-inductance of the transmitting coil after alignment. Location.
  • the method further includes: obtaining the Q value threshold and the AC impedance through the deviation relationship according to the self-inductance of the transmitting coil; For foreign object detection, Ploss foreign object detection is performed according to the AC impedance and the coupling parameter.
  • the embodiments of the present application further provide a wireless charging system, which will be described in detail below with reference to the accompanying drawings.
  • this figure is a schematic diagram of a wireless charging system provided by an embodiment of the present application.
  • the wireless charging system provided by the embodiments of the present application includes the wireless charging device 30 described in the above embodiments, and also includes the electronic device 20;
  • the electronic device 20 includes a receiving coil and a rectifier circuit.
  • the structure of the electronic device can be seen in FIG. 3 .
  • the wireless charging device 30 is used for wirelessly charging the electronic device 20 .
  • the wireless charging device 30 may be a wireless charging base.
  • the electronic device 20 may be a mobile phone or a wearable device, and the wearable device may be, for example, a watch or the like.
  • the wireless charging device pre-stores the parameters of the wireless charging device
  • the electronic device pre-stores the parameters of the electronic device
  • the electronic device sends the pre-stored parameters of the electronic device to the wireless charging device
  • the wireless charging device pre-stores the parameters of the wireless charging device according to the parameters of the wireless charging device.
  • the wireless charging device can fit the corresponding relationship between the Q value and the entire location space based on only a limited number of parameters, thereby reducing the requirements for hardware performance and storage space.
  • At least one (item) refers to one or more, and "a plurality” refers to two or more.
  • “And/or” is used to describe the relationship between related objects, indicating that there can be three kinds of relationships, for example, “A and/or B” can mean: only A exists, only B exists, and both A and B exist at the same time. , where A and B can be singular or plural.
  • the character “/” generally indicates that the associated objects are an “or” relationship.
  • At least one item(s) below” or similar expressions thereof refer to any combination of these items, including any combination of single item(s) or plural items(s).
  • At least one (a) of a, b or c can mean: a, b, c, "a and b", “a and c", “b and c", or "a and b and c" ", where a, b, c can be single or multiple.

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Abstract

本申请公开了一种无线充电设备、充电底座及异物检测方法，无线充电设备包括：谐振网络、逆变电路和控制器；控制器接收电子设备发送的电子设备参数，根据无线充电设备参数和电子设备参数拟合无线充电设备的Q值相对于位置空间的偏差关系，位置空间为发射线圈和电子设备的接收线圈之间的位置空间；其中电子设备参数包括：发射线圈和接收线圈之间至少一个相对位置无异物时的无线充电设备的Q1值和谐振网络的谐振频率f1；无线充电设备参数包括：无线充电设备和电子设备非耦合状态下无线充电设备的的初始Q值Q0和谐振网络的初始谐振频率f0；根据偏差关系进行异物检测。该方案异物检测的结果更准确，而且可以降低存储空间和对硬件性能的要求。

Description

一种无线充电设备、充电底座及异物检测方法
本申请要求于2020年11月25日提交中国国家知识产权局的申请号为202011338197.1、申请名称为“一种无线充电设备、充电底座及异物检测方法”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请涉及无线充电技术领域，尤其涉及一种无线充电设备、充电底座及异物检测方法。
背景技术
无线充电技术(wireless charging technology，WCT)利用电场、磁场、微波或者激光等传导介质以实现电能的无线传输，由于其具有无导线限制、无插拔等优势，目前在电子设备上的应用越来越广泛。目前，越来越多的电子设备采用无线充电设备为其进行无线充电，例如电子设备可以为手机、可穿戴设备等。无线充电设备中包括发射线圈，电子设备中包括接收线圈。发射线圈和接收线圈之间通过电磁场耦合来实现电能的无线传输。
无线充电技术的原理是通过发射端的发射线圈和接收端的接收线圈之间磁场耦合来传输电能。例如，对于手机的无线充电，无线充电设备是指无线充电器，电子设备是指手机。其中，发射线圈位于无线充电器中，接收线圈位于手机内部。但是，当发射线圈和接收线圈之间存在金属异物时，发射线圈和接收线圈之间变化的磁场会在金属异物中产生涡流损耗并产生热量，进而带来发热甚至起火等安全性问题。因此，异物检测(FOD，Foreign Object Detection)是无线充电技术需要解决的技术问题。目前应用比较广泛的FOD包括功率损耗法(Ploss，Power loss method)和Q值法。其中，Ploss是无线充电协会(WPC，Wireless power consortium)在Qi协议中定义的一种用于异物检测的方法。其中，利用Ploss来检测异物时，与发射线圈的交流阻抗有关系，因此，利用发射线圈的交流阻抗来获得Ploss。另外，Q值法是获得当前的Q值与Q值阈值进行比较判断是否存在异物。其中，Q值和交流阻抗存在线性转换关系。
但是，目前的异物检测技术不考虑发射端和接收端的相对位置的影响，目前也没有提供准确获得发射端和接收端之间的相对位置的方法。
发明内容
为了解决以上的技术问题，本申请提供一种无线充电设备、充电底座及异物检测方法，能够进行异物检测，且保证检测结果的准确性。
本申请实施例提供一种无线充电设备，不具体限定无线充电设备的实现类型，例如可以为无线充电器。无线充电设备用于为电子设备进行无线充电，电子设备可以为手机、平板、手表等可以被无线充电的设备。一般异物检测由无线充电设备进行，无线充电设备包括：谐振网络、逆变电路和控制器；谐振网络包括谐振电容和发射线圈；逆变电路的输入端用于连接直流电源，所述逆变电路的输出端用于连接所述谐振网络；因此无线充电设备的控制器接收电子设备发送的电子设备参数，该电子设备参数为电子设备中预存的参数。根据无线充电设备参数和电子设备参数拟合无线充电设备的Q 值相对于位置空间的偏差关系，此处的无线设备参数为无线设备预存的参数，位置空间为发射线圈和电子设备的接收线圈之间的位置空间；其中电子设备参数包括：发射线圈和接收线圈之间至少一个相对位置无异物时的无线充电设备的Q1值和所述谐振网络的谐振频率f1；无线充电设备参数包括：无线充电设备与电子设备非耦合状态下无线充电设备的的初始Q值Q0和谐振网络的初始谐振频率f0；控制器可以根据拟合的偏差关系进行异物检测。此处的非耦合状态是指发射线圈和接收线圈之间没有磁场耦合，不传递能量，即发射线圈和接收线圈距离较远。
由于Q值阈值与相对位置有关系，不同的相对位置对应的Q值阈值不同，为了异物检测的更准确，不能利用固定不变的Q值阈值进行异物检测。本申请实施例提供的无线充电设备无需存储Q值与整个位置空间的对应关系，同理，也无需存储发射线圈的交流阻抗与整个位置空间的对应关系。无线充电设备可以仅根据预存的有限数量的参数以及从电子设备接收其预存的有限数量的参数便可以拟合得到Q值相对于整个位置空间的对应关系，从而根据实际的相位位置通过拟合的偏差关系得到对应的Q值阈值，从而根据当前相位位置对应的Q值阈值进行异物检测。本申请实施例实现了对于Q值阈值的线性化，由于拟合偏差关系时从电子设备接收电子设备参数，因此，对于不同的电子设备拟合的偏差关系不同，从而实现了不同电子设备的归一化，因此，本申请实施例提供的无线充电设备不仅可以实现异物的精确检测，而且不必存储大量的数据，降低对于硬件性能和存储空间的要求。本申请适用于多种不同的电子设备，只要电子设备支持无线充电即可。
在一种可能的实现方式中，控制器可以在无线充电之前进行异物检测，即根据偏差关系获得Q值阈值，并在无线充电设备为电子设备充电之前根据Q值阈值进行Q值异物检测。
在一种可能的实现方式中，控制器可以在无线充电过程中进行异物检测，即根据偏差关系获得Q值阈值，根据Q值阈值以及Q值与发射线圈的交流阻抗的对应关系获得对应的交流阻抗；在无线充电设备为电子设备充电过程中根据获得的交流阻抗进行Ploss异物检测。其中对应关系可以为一种比例关系，或者一种线性比例关系。另外也可以为一种比例关系的变形，本申请实施例中不做限定，由于Q值与交流阻抗之间存在对应的映射关系，可以根据获得Q值阈值得到对应的交流阻抗，不必拟合交流阻抗相对于整个位置空间的偏差关系。
本申请实施例无线充电设备利用拟合的偏差关系，既可以进行充电前的异物检测，又可以进行充电过程中的异物检测，也可以只在充电前进行异物检测，也可以只在充电过程中进行异物检测。
在一种可能的实现方式中，偏差关系包括：发射线圈所在平面和接收线圈所在平面之间的竖直关系；控制器根据f0、Q0以及Q1值和f1拟合Q值相对于位置空间的竖直关系；通过竖直关系获得Q值阈值，并根据Q值阈值以及Q值与发射线圈的交流阻抗的对应关系获得对应的交流阻抗。当偏差关系仅包括竖直关系时尤其适用于发射线圈和接收线圈在径向不存在偏差，或者偏差可以忽略，仅考虑竖直相对位置对Q值阈 值以及对交流阻抗的影响即可。例如对于带有对正功能的无线充电设备，可以移动发射线圈与接收线圈在径向上对正。
在一种可能的实现方式中，电子设备参数包括发射线圈和接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12；偏差关系包括：发射线圈和接收线圈之间径向的水平关系以及发射线圈所在平面和接收线圈所在平面之间的竖直关系；控制器根据Q11、f11、Q12和f12拟合Q值相对于位置空间的水平关系；通过以下任一方式拟合Q值相对于位置空间的竖直关系：根据f0、Q0、Q11和f11；或，根据f0、Q0、Q12和f12拟合Q值相对于位置空间的竖直关系；或，根据Q0、f0和水平关系中的至少一个点对应的Q和f拟合Q值相对于位置空间的竖直关系；通过水平关系和竖直关系获得Q值阈值，并根据Q值阈值以及Q值与发射线圈的交流阻抗的对应关系获得对应的交流阻抗。
在一种可能的实现方式中，本实施例中拟合偏差关系添加了预存耦合参数，应该理解，预存耦合参数是预先存储的，并不是在充电时对应的耦合状态下在线测试获得的。偏差关系包括：发射线圈和接收线圈之间径向的水平关系以及发射线圈所在平面和接收线圈所在平面之间的竖直关系；电子设备参数还包括：发射线圈和接收线圈之间至少一个相对位置无异物时的预存耦合参数；预存耦合参数包括以下至少一项：发射线圈和接收线圈之间的耦合系数和互感；控制器根据f0、Q0以及发射线圈和接收线圈之间至少一个相对位置的Q值和f拟合Q值相对于位置空间的竖直关系；根据预存耦合参数和发射线圈和接收线圈之间至少一个相对位置的Q值拟合Q值相对于位置空间的水平关系；通过竖直关系和水平关系获得Q值阈值，并根据Q值阈值以及Q值与发射线圈的交流阻抗的对应关系获得对应的交流阻抗。
在一种可能的实现方式中，本实施例中添加两个相对位置的预存耦合参数，拟合的偏差关系更加准确。应该理解，预存耦合参数是预先存储的，并不是在充电时对应的耦合状态下在线测试获得的。电子设备参数包括发射线圈和接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12；偏差关系包括：发射线圈和接收线圈之间径向的水平关系以及发射线圈所在平面和接收线圈所在平面之间的竖直关系；电子设备参数还包括：第一位置的预存耦合参数和第二位置的预存耦合参数；预存耦合参数包括以下至少一项：发射线圈和接收线圈之间的耦合系数和互感；控制器根据Q11、Q12、第一位置的预存耦合参数和第二位置的预存耦合参数拟合Q值相对于位置空间的水平关系；通过以下任一方式拟合Q值相对于位置空间的竖直关系：根据f0、Q0、Q11和f11；或，根据f0、Q0、Q12和f12拟合Q值相对于位置空间的竖直关系；或，根据Q0、f0和水平关系中的至少一个点对应的Q和f拟合Q值相对于位置空间的竖直关系；通过竖直关系和水平关系获得Q值阈值，并根据Q值阈值以及Q值与发射线圈的交流阻抗的对应关系获得对应的交流阻抗。
在一种可能的实现方式中，当偏差关系仅包括竖直关系时尤其适用于以下技术方案，控制器根据无线充电设备和电子设备在当前相对位置的谐振网络的谐振频率或发射线圈的自感通过竖直关系获得Q值阈值，并根据Q值阈值以及Q值与发射线圈的交 流阻抗的对应关系获得对应的交流阻抗。
下面介绍利用偏差关系获得Q值阈值的具体实现方式。
在一种可能的实现方式中，控制器获得无线充电设备和电子设备在耦合状态下的耦合参数和发射线圈的自感L1；耦合状态下的耦合参数包括以下至少一项：发射线圈和接收线圈之间的耦合系数和互感；根据耦合状态下的耦合参数和L1通过偏差关系获得Q值阈值，并根据Q值阈值以及Q值与发射线圈的交流阻抗的对应关系获得对应的交流阻抗；耦合状态下的耦合参数与水平关系存在单调关系，L1与竖直关系存在单调关系。应该理解，此处的耦合参数为在线测试获得耦合参数，而不是预存的耦合参数。
在一种可能的实现方式中，控制器，具体用于接收电子设备发送的无线充电设备和电子设备在耦合状态下接收线圈的自感L2；根据发射线圈的电流、耦合状态下发射线圈的自感L1、L2和接收线圈对应的整流电压获得耦合状态下的耦合参数。
在一种可能的实现方式中，控制器，具体用于接收电子设备发送的无线充电设备和电子设备在非耦合状态下接收线圈的自感L20；根据耦合状态下发射线圈的自感L1、非耦合状态下发射线圈的自感L10、L20获得耦合状态下接收线圈的自感L2，根据L1、L2和接收线圈对应的整流电压获得耦合状态下的耦合参数。一般情况下，发射线圈的自感和接收线圈的自感存在预设的比例关系。例如，控制器32根据发射端在非耦合状态下发射线圈的自感L10、耦合状态下发射线圈的自感L1、L20和预设的比例关系可以获得耦合状态下接收线圈的自感L2。对于这种情况，电子设备无需获得L2，仅获得L20即可。
在一种可能的实现方式中，控制器，还用于接收电子设备发送的无线充电设备和电子设备在耦合状态下辅助线圈的自感L3；根据发射线圈的电流、耦合状态下发射线圈的自感L1、L3和辅助线圈对应的整流电压获得耦合状态下的耦合参数。
在一种可能的实现方式中，控制器，还用于接收电子设备发送的无线充电设备和电子设备在非耦合状态下辅助线圈的自感L30；根据耦合状态下发射线圈的自感L1、非耦合状态下发射线圈的自感L10、L30获得耦合状态下辅助线圈的自感L3，根据L1、L3和辅助线圈对应的整流电压获得耦合状态下的耦合参数。一般情况下，发射线圈的自感和辅助线圈的自感存在预设的比例关系。因此，控制器根据非耦合状态下发射线圈的自感L10、耦合状态下发射线圈的自感L1、L30和预设的比例关系可以获得耦合状态下辅助线圈的自感L3。对于这种情况，电子设备无需获得L3，即获得L30即可。
在一种可能的实现方式中，控制器，还用于获得无线充电设备和电子设备在耦合状态下的耦合参数，具体用于根据交流阻抗和耦合状态下的耦合参数进行Ploss异物检测。获得耦合系数k后，便可以在线精确计算当前耦合系数k对应的功率损耗，精度越高，则可以对应适用的无线充电的功率越大，因此可以支持更大功率的无线充电。
在一种可能的实现方式中，还包括：发射线圈的电流检测电路；电流检测电路，用于检测谐振电容两端的电压差；控制器，用于根据电压差获得发射线圈的电流。
为了在逆变电路为全桥电路时，更准确地获得发射线圈的电流，在一种可能的实现方式中，电流检测电路包括：第一电压检测电路、第二电压检测电路和差分电路； 第一电压检测电路，用于检测谐振电容的第一端的第一电压，将第一电压分压后发送给差分电路的第一输入端；第二电压检测电路，用于检测谐振电容的第二端的第二电压，将第二电压分压后发送给差分电路的第二输入端；差分电路，用于获得第一输入端输入的电压和第二输入端输入的电压的差分结果；控制器，用于根据差分结果获得发射线圈的电流。即本实施例为了更准确获得全桥逆变电路连接的发射线圈的电流，采用了差分电路的采样形式。
在一种可能的实现方式中，控制器，还用于根据发射线圈的自感和耦合参数确定发射线圈和接收线圈之间的水平相对位置和竖直相对位置，根据水平相对位置移动发射线圈，使发射线圈与接收线圈对正；发射线圈的自感与竖直相对位置存在单调关系，耦合参数与水平相对位置存在单调关系。
在一种可能的实现方式中，控制器，具体用于获得无线充电设备和电子设备在两个不同相对位置对应的两个水平相对位置，获得分别以两个水平相对位置为半径的第一圆周和第二圆周，获得第一圆周和第二圆周的交叉点，控制发射线圈对正至交叉点。
在一种可能的实现方式中，控制器，还用于移动发射线圈到第三位置，第三位置区别于两个不同相对位置；获得移动过程中的以下至少一项参数，根据至少一项参数的变化趋势确定发射线圈对正至的交叉点；至少一项参数包括：耦合参数、充电效率、发射线圈的自感、发射线圈的电流和接收端的输出电压。
在一种可能的实现方式中，控制器，具体用于控制发射线圈移动到第四位置，第四位置与两个不同相对位置不在同一直线，获得第四位置对应的发射线圈的自感与耦合参数；根据第四位置对应的发射线圈的自感和耦合参数确定水平相对位置和竖直相对位置，依据水平相对位置确定第三圆周，控制发射线圈移动至第三圆周与交叉点的公共点。以上提供的对正方式，可以在很少的移动次数下即可实现发射线圈与接收线圈的对正。当发射线圈和接收线圈对正以后，异物检测时仅考虑竖直相对偏差引起的误差即可，水平相位位置已经被消除。
在一种可能的实现方式中，还包括：对位机构；控制器，用于控制对位机构驱动发射线圈，以使发射线圈与接收线圈对正。本申请实施例中不限定对位机构的具体实现形式。
在一种可能的实现方式中，控制器，在发射线圈与接收线圈对正后，还用于根据发射线圈的自感通过偏差关系获得Q值阈值，并通过Q值与发射线圈的交流阻抗之间的比例关系根据Q值阈值获得对应的交流阻抗；在无线充电设备为电子设备充电之前根据Q值阈值进行Q值异物检测，在无线充电设备为电子设备充电过程中根据交流阻抗和耦合状态下的耦合参数进行Ploss异物检测。
在一种可能的实现方式中，根据交流阻抗和耦合状态下的耦合参数进行Ploss异物检测，具体通过以下公式获得无线充电的功率损耗；
P tx loss＝f(Vin)+f(TxACR,k,I1)
f(TxACR,k,I1)＝(a+TxACR*f(k))*I1 2+b*I1+c；
其中，Vin为逆变电路的母线电压；TxACR为发射线圈的交流阻抗ACR；I1为发射线圈的电流；a、b、c、d为无线充电设备的已知参数。由于本实施例中在Ploss异物检测时 引入了新的参数，即耦合状态下的耦合参数，利用耦合参数可以获得准确的系数k，从而获得准确的功耗，进而进行精确的异物检测，当异物检测的结果越精确时，则可以适用于更大无线充电功率对应的异物检测。
本申请实施例还提供一种无线充电底座，包括：用于为电子设备进行无线充电，包括：电源接口、谐振网络、逆变电路、控制器和发射线圈底盘；电源接口，用于连接适配器传输的直流电；谐振网络包括谐振电容和发射线圈；发射线圈底盘，用于放置发射线圈；逆变电路的输入端用于连接电源接口，逆变电路的输出端用于连接谐振网络；控制器，用于接收电子设备发送的电子设备参数，根据无线充电设备参数和电子设备参数拟合无线充电设备的Q值相对于位置空间的偏差关系，位置空间为发射线圈和电子设备的接收线圈之间的位置空间；其中电子设备参数包括：发射线圈和接收线圈之间至少一个相对位置无异物时的无线充电设备的Q1值和谐振网络的谐振频率f1；无线充电设备参数包括：无线充电设备与电子设备非耦合状态下无线充电设备的的初始Q值Q0和谐振网络的初始谐振频率f0；控制器，还用于根据偏差关系进行异物检测。
例如，无线充电底座为充电圆盘，或者立体充电座，本申请实施例中不具体限定无线充电底座的具体几何形态。无线充电底座为电子设备充电时，一般无线充电底座可以平行于水平面，电子设备放置在无线充电底座上方。另外，当无线充电底座为竖直于水平面时，电子设备所在平面需要与无线充电底座所在平面平行，以使发射线圈与接收线圈更好地耦合。
在一种可能的实现方式中，控制器，具体用于根据偏差关系获得Q值阈值，并在无线充电设备为电子设备充电之前根据Q值阈值进行Q值异物检测。
在一种可能的实现方式中，控制器，具体用于根据偏差关系获得Q值阈值，根据Q值阈值以及Q值与发射线圈的交流阻抗的对应关系获得对应的交流阻抗；在无线充电设备为电子设备充电过程中根据获得的交流阻抗进行Ploss异物检测。
在一种可能的实现方式中，电子设备参数包括发射线圈和接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12；偏差关系包括：发射线圈和接收线圈之间径向的水平关系以及发射线圈所在平面和接收线圈所在平面之间的竖直关系；控制器，具体用于根据Q11、f11、Q12和f12拟合Q值相对于位置空间的水平关系；通过以下任一方式拟合Q值相对于位置空间的竖直关系：根据f0、Q0、Q11和f11；或，根据f0、Q0、Q12和f12拟合Q值相对于位置空间的竖直关系；或，根据Q0、f0和水平关系中的至少一个点对应的Q和f拟合Q值相对于位置空间的竖直关系；通过水平关系和竖直关系获得Q值阈值，并根据Q值阈值以及Q值与发射线圈的交流阻抗的对应关系获得对应的交流阻抗。
在一种可能的实现方式中，电子设备参数包括发射线圈和接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12；偏差关系包括：发射线圈和接收线圈之间径向的水平关系以及发射线圈所在平面和接收线圈所在平面之间的竖直关系；电子设备参数还包括：第一位置的预存耦合参数和第二位置的预存耦合参数；预存耦合参数包括以下至少一项：发射线圈和接收线圈之间的耦 合系数和互感；控制器，具体用于根据Q11、Q12、第一位置的预存耦合参数和第二位置的预存耦合参数拟合Q值相对于位置空间的水平关系；通过以下任一方式拟合Q值相对于位置空间的竖直关系：根据f0、Q0、Q11和f11；或，根据f0、Q0、Q12和f12拟合Q值相对于位置空间的竖直关系；或，根据Q0、f0和水平关系中的至少一个点对应的Q和f拟合Q值相对于位置空间的竖直关系；通过竖直关系和水平关系获得Q值阈值，并根据Q值阈值以及Q值与发射线圈的交流阻抗的对应关系获得对应的交流阻抗。
本申请实施例还提供一种无线充电的异物检测方法，应用于无线充电设备，无线充电设备包括：谐振网络和逆变电路；谐振网络包括谐振电容和发射线圈；逆变电路的输入端用于连接直流电源，逆变电路的输出端用于连接谐振网络；该方法包括：接收电子设备发送的电子设备参数；根据无线充电设备参数和电子设备参数拟合无线充电设备的Q值相对于位置空间的偏差关系，位置空间为发射线圈和电子设备的接收线圈之间的位置空间；其中电子设备参数包括：发射线圈和接收线圈之间至少一个相对位置无异物时的无线充电设备的Q1值和谐振网络的谐振频率f1；无线充电设备参数包括：无线充电设备与电子设备非耦合状态下无线充电设备的的初始Q值Q0和谐振网络的初始谐振频率f0；根据偏差关系进行异物检测。
在一种可能的实现方式中，根据偏差关系进行异物检测，具体包括：根据偏差关系获得Q值阈值，并在无线充电设备为电子设备充电之前根据Q值阈值进行Q值异物检测。
在一种可能的实现方式中，根据偏差关系进行异物检测，具体包括：根据偏差关系获得Q值阈值；根据Q值阈值以及Q值与发射线圈的交流阻抗的对应关系获得对应的交流阻抗；在无线充电设备为电子设备充电过程中根据获得的交流阻抗进行Ploss异物检测。
在一种可能的实现方式中，电子设备参数包括发射线圈和接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12；偏差关系包括：发射线圈和接收线圈之间径向的水平关系以及发射线圈所在平面和接收线圈所在平面之间的竖直关系；根据无线充电设备参数和电子设备参数拟合无线充电设备的Q值相对于位置空间的偏差关系，具体包括：根据Q11、f11、Q12和f12拟合Q值相对于位置空间的水平关系；通过以下任一方式拟合Q值相对于位置空间的竖直关系：根据f0、Q0、Q11和f11；或，根据f0、Q0、Q12和f12拟合Q值相对于位置空间的竖直关系；或，根据Q0、f0和水平关系中的至少一个点对应的Q和f拟合Q值相对于位置空间的竖直关系；根据偏差关系获得Q值阈值，具体包括：通过水平关系和竖直关系获得Q值阈值。
在一种可能的实现方式中，偏差关系包括：发射线圈和接收线圈之间径向的水平关系以及发射线圈所在平面和接收线圈所在平面之间的竖直关系；电子设备参数还包括：发射线圈和接收线圈之间至少一个相对位置无异物时的预存耦合参数；预存耦合参数包括以下至少一项：发射线圈和接收线圈之间的耦合系数和互感；根据无线充电 设备参数和电子设备参数拟合无线充电设备的Q值相对于位置空间的偏差关系，具体包括：根据f0、Q0以及发射线圈和接收线圈之间至少一个相对位置的Q值和f拟合Q值相对于位置空间的竖直关系；根据预存耦合参数和发射线圈和接收线圈之间至少一个相对位置的Q值拟合Q值相对于位置空间的水平关系；根据偏差关系获得Q值阈值，具体包括：通过竖直关系和水平关系获得Q值阈值。
在一种可能的实现方式中，电子设备参数包括发射线圈和接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12；偏差关系包括：发射线圈和接收线圈之间径向的水平关系以及发射线圈所在平面和接收线圈所在平面之间的竖直关系；电子设备参数还包括：第一位置的预存耦合参数和第二位置的预存耦合参数；预存耦合参数包括以下至少一项：发射线圈和接收线圈之间的耦合系数和互感；根据无线充电设备参数和电子设备参数拟合无线充电设备的Q值相对于位置空间的偏差关系，具体包括：根据Q11、Q12、第一位置的预存耦合参数和第二位置的预存耦合参数拟合Q值相对于位置空间的水平关系；通过以下任一方式拟合Q值相对于位置空间的竖直关系：根据f0、Q0、Q11和f11；或，根据f0、Q0、Q12和f12拟合Q值相对于位置空间的竖直关系；或，根据Q0、f0和水平关系中的至少一个点对应的Q和f拟合Q值相对于位置空间的竖直关系；根据偏差关系获得Q值阈值，具体包括：通过竖直关系和水平关系获得Q值阈值。
与现有技术相比，本申请实施例提供的技术方案具有以下优点：
由于Q值在发射线圈和接收线圈的不同相对位置时对应的Q阈值不同，因此，利用不同的Q值阈值进行异物判断时将影响判断的结果。本申请实施例正是考虑了相对位置对于Q值阈值的影响，而根据相对位置对应的Q值阈值进行异物检测，可以使异物检测结果更加准确。由于Q值与相对位置存在对应关系，因此，可以根据发射线圈和接收线圈的相对位置获得对应的Q值阈值。但是实际产品中，为了降低存储空间和对硬件性能的要求，可以不必存储整个自由度空间内Q值与相对位置的所有对应数值，本申请实施例提供的技术方案可以根据有限数量的无线充电设备参数和电子设备参数来拟合Q值相对于整个位置空间的偏差关系，即拟合表征的Q值相对于水平相对位置和竖直相对位置的对应关系。因此，即控制器利用发射线圈和接收线圈至少一个相对位置无异物时的Q1值和谐振频率f1，非耦合状态下的初始Q值Q0和初始谐振频率f0获得Q值相对于整个位置空间的偏差关系，获得Q值相对于整个位置空间的偏差关系以后，可以通过偏差关系对当前位置进行异物检测。
附图说明
图1为本申请实施例提供的无线充电系统的示意图；
图2为图1中电子设备的结构示意图；
图3为本申请实施例提供的无线充电系统的电路示意图；
图4为本申请实施例提供的一种发射线圈的交流阻抗随相对位置变化的等势图；
图5为本申请实施例提供的一种无异物时发射端Q值随相对位置变化的等势图；
图6为本申请实施例提供的一种无线充电设备的示意图；
图7为本申请实施例提供的发射线圈的自感L1与相对位置的关系示意图；
图8为本申请实施例提供的耦合系数k与相对位置的关系示意图；
图9为本申请实施例提供的互感M与相对位置的关系示意图；
图10为本申请实施例提供的一种无线充电系统的示意图；
图11为本申请实施例提供的一种发射线圈的电流的检测电路图；
图12为本申请实施例提供的另一种发射线圈的电流的检测电路图；
图13为本申请实施例提供的另一种无线充电设备的示意图；
图14为本申请实施例提供的一种对位结构的示意图；
图15为本申请实施例提供的一种发射线圈的对位原理示意图；
图16为本申请实施例提供的一种带有机械卡位的无线充电设备的示意图；
图17为本申请实施例提供的一种带有磁吸对位的无线充电设备的示意图；
图18为本申请实施例提供的一种无线充电的异物检测方法的流程图；
图19为本申请实施例提供的再一种无线充电的异物检测方法的流程图；
图20为本申请实施例提供的又一种无线充电的异物检测方法的流程图；
图21为本申请实施例提供的另一种无线充电的异物检测方法的流程图；
图22为本申请实施例提供的对正前的异物检测方法的流程图；
图23为本申请实施例提供的带有对位的异物检测方法的流程图；
图24为本申请实施例提供的一种无线充电系统的示意图。
具体实施方式
以下说明中的“第一”、“第二”等用词仅用于描述目的，而不能理解为指示或暗示相对重要性或者隐含指明所指示的技术特征的数量。由此，限定有“第一”、“第二”等的特征可以明示或者隐含地包括一个或者更多该特征。在本申请的描述中，除非另有说明，“多个”的含义是两个或两个以上。
此外，本申请中，“上”、“下”等方位术语可以包括但不限于相对附图中的部件示意置放的方位来定义的，应当理解到，这些方向性术语可以是相对的概念，它们用于相对于的描述和澄清，其可以根据附图中部件附图所放置的方位的变化而相应地发生变化。
在本申请中，除非另有明确的规定和限定，术语“连接”应做广义理解，例如，“连接”可以是固定连接，也可以是可拆卸连接，或成一体；可以是直接相连，也可以通过中间媒介间接相连。此外，术语“耦接”可以是实现信号传输的电性连接的方式。“耦接”可以是直接的电性连接，也可以通过中间媒介间接电性连接。
本申请实施例不具体限定电子设备的类型，电子设备可以为手机(mobile phone)、平板电脑(pad)、带无线收发功能的电脑、智能穿戴产品(例如，智能手表、智能手环、耳机等)、虚拟现实(virtual reality，VR)终端设备、增强现实(augmented reality AR)终端设备等具有无线设备。上述电子设备还可以是无线充电电动汽车、无线充电家用电器(例如豆浆机、扫地机器人)、无人机等电子产品。
为了使本领域技术人员更好地理解本申请实施例提供的技术方案，下面先介绍电子设备无线充电的应用场景，以电子设备为手机为例进行介绍。
参见图1，该图为本申请实施例提供的无线充电系统的示意图。
当电子设备为手机时，无线充电设备为无线充电器02，无线充电器02用于为电子设备01(即手机)进行无线充电。图示的无线充电器02支撑电子设备01水平放置在其上方，在一些实施例中，无线充电器02还可以具备其它形态，例如为立式无线充电器，具备一定的倾斜度，以使电子设备01可以倚靠贴紧无线充电器02。
该无线充电系统包括设置于电子设备01内的无线充电接收(Receive，RX)装置20和与该无线充电接收端20相耦接的电池50。
该无线充电系统还包括设置于无线充电器02内的无线充电发射(Transmit，TX)端30，以及与该无线充电发射端30相耦接的适配器40，该适配器40用于提供充电电能。
无线充电发射端30对无线充电接收端20进行功率传输；无线充电发射端30和无线充电接收端20之间可以传输控制信号或者传输充电数据。传输控制信号或者传输充电数据可以通过带内通讯实现，也可以通过带外通讯实现。无线充电发射端30和无线充电接收端20之间通过蓝牙(Bluetooth)、无线宽带(Wireless-Fidelity，WiFi)、紫蜂协议(Zigbee)、射频识别技术(Radio Frequency Identification，RFID)、远程(Long range，Lora)无线技术或近距离无线通信技术(Near Field Communication，NFC)等带外通讯方式实现无线连接，以使得无线充电发射端30和无线充电接收端20之间可以建立无线通信。
该充电数据可以用于指示充电类型。在一些实施例中，该充电数据可以为充电协议，例如无线充电联盟(Wireless Power Consortium，WPC)推出的无线充电标准Qi，例如BPP(Basic Power Profile)协议，或者EPP(Extended Power Profile)协议等。
参见图2，该图为图1中电子设备的结构示意图。
以上述电子设备01为手机为例，其主要包括显示屏(Display Panel，DP)10。该显示屏10可以为液晶显示(Liquid Crystal Display，LCD)屏，或者，有机发光二极管(Organic Light Emitting Diode，OLED)显示屏等，当手机采用折叠屏架构或多屏架构时，手机还可以包括多块屏幕，多块屏幕还可以是以上不同类型屏幕的组合，本申请对此不作限定。
上述电子设备01还可以包括中框11和壳体12。显示屏10和壳体12分别位于中框11的两侧，显示屏10的背面朝向壳体12，且该显示屏10和壳体12通过中框11相连接。其中，中框11包括承载板110以及绕承载板110一周的边框111。电子设备01还可以包括印刷电路板(Printed Circuit Boards，PCB)。
需要说明的是，实际产品中，发射线圈和接收线圈一般设置为圆盘形状。
下面结合附图介绍无线充电的工作原理。
参见图3，该图为本申请实施例提供的无线充电系统的电路示意图。
无线充电发射端30，用于发射磁场能量。无线充电发射端30可以位于无线充电设备中。
无线充电发射端30包括逆变电路DC/AC31，逆变电路DC/AC31的输入端用于连接直 流电源，例如连接适配器输出的直流电，逆变电路DC/AC31的输出端连接谐振网络，谐振网络包括谐振电容C1和发射线圈L1。本申请实施例中以谐振电容C1和发射线圈L1串联谐振为例。
无线充电接收端20，用于接收无线充电发射端30发射的磁场能量。无线充电接收端20可以位于电子设备中。
无线充电接收端20包括接收线圈L2、电容C2和整流电路AC/DC21。整流电路AC/DC21将接收线圈L2输出的交流电转换为直流电为电池进行充电。
为了描述方便，下面将无线充电发射端简称为发射端，将无线充电接收端简称为接收端。
无线充电设备将输入的电能变换为磁场能量后，无线充电设备通过无线充电发射端30发射磁场能量；电子设备位于无线充电设备附近时，电子设备通过无线充电接收端20接收无线充电设备发出的磁场能量，并将磁场能量变换为电能对电子设备充电。由此，实现电能由无线充电设备向电子设备的无线传输。
当无线充电设备和电子设备之间通过带内通讯时，包括可通讯区域和不可通讯区域。其中，电子设备为手机或可穿戴设备时，例如可通讯区域一般是指发射线圈和接收线圈的平面位置偏差在10mm以内，Z向距离也在10mm以内，其中Z向距离指的是无线充电设备和电子设备之间的高度距离，例如发射线圈水平放置，接收线圈水平放置，Z向指的是发射线圈与接收线圈之间的竖直距离，Z向偏差是指竖直相对位置。例如当发射线圈为圆盘形状，接收线圈为圆盘形状，无线充电设备平放时，发射线圈所在的平面与水平面平行，手机平放在无线充电设备上，接收线圈所在平面与发射线圈所在平面几乎平行，由于发射线圈和接收线圈均为圆盘形状，因此，发射线圈和接收线圈的平面位置偏差指的是发射线圈的中心与接收线圈的中心在平面上的偏差，即径向偏差，又可称为水平相对位置。
无线充电时，无线充电设备和电子设备之间可能会存在异物，例如：金属异物，发射线圈与接收线圈之间产生的变化磁场在金属异物产生涡流损耗并产生热量。
因此，FOD是无线充电技术需要解决的技术问题。异物检测的方法通常包括Ploss和Q值法。Ploss法根据水平相对位置和竖直相对位置获得发射线圈的交流阻抗，根据发射线圈的交流阻抗和充电过程中发射线圈的电流获得发射端的功率损耗，根据发射端的输入功率和发射端的功率损耗获得发射功率，根据发射功率和接收端的接收功率获得异物损耗，当异物损耗大于功率阈值时，确定发射端和接收端之间存在异物。
无线充电中，Q值与位置偏差存在单调关系，Ploss也与位置偏差存在单调关系。下面结合附图进行详细说明。
参见图4，该图为本申请实施例提供的一种发射线圈的交流阻抗随相对位置变化的等势图。
其中，横坐标为水平相对位置(单位：毫米)，纵坐标为竖直相对位置(单位：毫米)，图中虚线的交点为已知水平相对位置和竖直相对位置，且确定发射端和接收端102之间无异物时的发射线圈的交流阻抗。从图中可以看出，发射端和接收端102之间的 相对位置会影响到发射线圈的交流阻抗。
参见图5，该图为本申请实施例提供的一种无异物时发射端Q值随相对位置变化的等势图。
其中，横坐标为水平相对位置(单位：毫米)，纵坐标为竖直相对位置(单位：毫米)，图中虚线的交点为已知水平相对位置和竖直相对位置，且确定发射端和接收端之间无异物时的发射线端的Q值。从图中可以看出，发射端和接收端之间无异物时，不同的相对位置对应的发射端的Q值不同。
从以上图4和图5可知，Q值和交流阻抗均与相对位置存在单调关系，如果发射线圈和接收线圈之间没有对正，即存在位置偏差时，用来进行异物检测的Q值和Ploss的标准将发生改变，如果忽略位置偏差带来的影响，无论利用Q值还是利用Ploss进行异物检测，均可能导致异物检测不准确。因此，为了解决位置偏差导致的异物检测不准确的问题，需要根据当前位置对应的Q值阈值进行FOD才可能准确地进行异物检测。同理，需要根据当前位置对应的交流阻抗进行Ploss计算，按照统一的Ploss阈值进行FOD才可能准确地进行异物检测。
一般情况下，无线充电系统的异物检测，在无线充电设备为电子设备充电之前利用Q值进行异物检测，在无线充电设备为电子设备充电过程中利用Ploss进行异物检测。由于Q值与发射线圈的交流阻抗存在对应关系，例如Q值与交流阻抗存在比例关系，下面以Q值与交流阻抗之间存在线性比例关系为例进行介绍，当然也可以为比例关系的其他表现形式。一般可以先获得Q值，然后根据Q值与发射线圈的交流阻抗之间的线性比例关系获得交流阻抗，下面结合公式进行详细介绍。
Q值的定义如下公式(1)；
Figure PCTCN2021110254-appb-000001
其中，L 1为发射线圈的电感值，R tx acr为发射线圈的交流阻抗，f为无线充电设备的谐振网络的谐振频率。
从公式(1)可以看出，Q值与发射线圈的交流阻抗存在换算关系，当获得Q值以后，可以根据公式(1)获得发射线圈的交流阻抗，进而根据发射线圈的交流阻抗获得进行Ploss异物检测。
需要说明的是，利用Q值和Ploss进行异物检测的具体过程，在此不再赘述。本申请实施例具体介绍获得Q值和发射线圈的交流阻抗的具体实现方式。
从图5可以看出，Q值与位置空间存在对应关系，但是实际产品实现时，一般不会以图的形式在无线充电设备中存储Q值与位置空间的对应关系，以及存储发射线圈的交流阻抗与位置空间的对应关系，例如，如果采用分度值为1mm的数值表，即针对一个具体型号的电子设备，涉及竖直相对位置或水平相对位置的偏位范围，数据量一般涉及上百个之多，则对于硬件的存储空间以及控制器的处理能力均带来较大压力。因此，本申请实施例为了解决以上技术问题，提供了一种无线充电设备，该无线充电设备不需存储Q值与整个位置空间的对应关系，同理也不需存储发射线圈的交流阻抗与整个位置空间的对应关系。无线充电设备仅根据有限数量的参数便可以拟合出Q值相对于整个位置空间的对应关系，从而 可以降低对于硬件性能和存储空间的要求。
无线充电设备实施例一：
参见图6，该图为本申请实施例提供的一种无线充电设备的示意图。
本实施例提供的无线充电设备用于为电子设备进行无线充电，无线充电设备包括：谐振网络、逆变电路和控制器32；
谐振网络包括谐振电容C1和发射线圈L1；本实施例中以谐振电容C1和发射线圈L1串联形成谐振网络为例进行介绍。
逆变电路的输入端用于连接直流电源，逆变电路的输出端用于连接谐振网络。
本实施例中以逆变电路为全桥电路为例进行介绍，逆变电路包括四个可控开关管，分别为第一开关管S1-第四开关管S4。如图6所示，第一开关管S1的第一端连接直流电源的正极，第一开关管S1的第二端连接第二开关管S2的第一端，第二开关管S2的第二端连接直流电源的负极，即S1和S2串联后连接在直流电源的正极和负极之间。同理，第三开关管S3的第一端连接直流电源的正极，第三开关管S3的第二端连接第四开关管S4的第一端，第四开关管S4的第二端连接直流电源的负极，即S3和S4串联后连接在直流电源的正极和负极之间。其中S1的第二端通过串联的C1和L1连接S3的第二端。
其中，L2为电子设备的接收线圈，例如电子设备为手机，则接收线圈L2位于手机内部。
控制器32，用于接收所述电子设备发送的电子设备参数，根据无线充电设备参数和所述电子设备参数拟合所述无线充电设备的Q值相对于位置空间的偏差关系，所述位置空间为所述发射线圈和所述电子设备的接收线圈之间的位置空间；其中所述电子设备参数包括：所述发射线圈和所述接收线圈之间至少一个相对位置无异物时的所述无线充电设备的Q1值和所述谐振网络的谐振频率f1；所述无线充电设备参数包括：所述无线充电设备与所述电子设备非耦合状态下所述无线充电设备的的初始Q值Q0和所述谐振网络的初始谐振频率f0。
控制器得到偏差关系以后，还用于根据所述偏差关系进行异物检测。
需要说明的是，电子设备参数是电子设备预存的初始参数，例如电子设备为手机，可以为手机出厂时即预存的参数。电子设备参数包括：至少一个位置无异物时的Q值和谐振频率f。至少一个位置是指无线充电设备和电子设备之间的相对位置，例如可以为一个相对位置下对应的参数，也可以为两个位置下对应的参数，也可以为多个位置下对应的参数，可以理解的是，相对位置越多，对应的参数越多，则拟合出来的偏差关系越准确。例如，两个相对位置无异物时的Q值是指手机相对于无线充电器两个不同位置时，手机测得的Q值，而两个位置无异物时的谐振频率f是指手机相对于无线充电器两个不同位置时，无线充电器的谐振网络的谐振频率f。
需要说明的是，无线充电设备与电子设备之间的相对位置一般用发射线圈和接收线圈之间的相对位置来表征。发射线圈和接收线圈一般设计为圆盘形状，因此，发射线圈和接收线圈之间的相对位置是指两个圆盘的圆心之间的位置偏差。可以理解的是，当发射线圈 和接收线圈为其他形状时，相对位置也是指发射线圈的中心与接收线圈的中心之间的位置偏差。
无线充电设备参数一般为无线充电设备预存的参数，例如无线充电器预存的参数。无线充电设备参数包括：无线充电设备与电子设备非耦合状态下的初始Q值Q0和初始谐振频率f0。非耦合状态是指无线充电设备和电子设备的距离较远，还没有进行电磁耦合。即对于无线充电器，还检测不到手机时的无线充电器的Q0和f0。
本申请实施例提供的无线充电设备的控制器32可以根据有限数量的无线充电设备参数和电子设备参数拟合Q值相对于整个位置空间的偏差关系，即拟合类似图5所表征的Q值相对于水平相对位置和竖直相对位置的对应关系。因此，无线充电设备不需存储整个位置空间的Q值与水平相对位置以及Q值与竖直相对位置的所有数据，从而大大降低存储空间。即控制器32利用至少一个相对位置无异物时的Q1值和谐振频率f1，非耦合状态下的初始Q值Q0和初始谐振频率f0获得Q值相对于整个位置空间的偏差关系，获得Q值相对于整个位置空间的偏差关系以后，可以通过偏差关系获得当前位置对应的Q值，从而根据Q值进行异物检测。由于Q值与发射线圈的交流阻抗存在公式(1)所示的关系，因此，可以由Q值获得对应的交流阻抗，即可以交流阻抗相对于整个位置空间的偏差关系便可以省略，通过Q值便可以换算得到交流阻抗，从而根据交流阻抗进行Ploss异物检测。
控制器得到偏差关系后，在无线充电之前可以进行Q值异物检测，在无线充电过程中可以进行Ploss异物检测，下面分别来介绍。应该理解，无论是Q值异物检测，还是Ploss异物检测，只要利用本申请实施例提供的偏差关系，则均在本申请的保护范围内。
控制器根据所述偏差关系获得Q值阈值，并在无线充电设备为电子设备充电之前根据Q值阈值进行Q值异物检测。
控制器，具体用于根据偏差关系获得Q值阈值，根据Q值阈值以及Q值与发射线圈的交流阻抗的对应关系获得对应的交流阻抗；在无线充电设备为电子设备充电过程中根据获得的所述交流阻抗进行Ploss异物检测。
从图5可以看出，Q值相对于整个空间的相对位置关系包括水平相对位置和竖直相对位置，因此本申请实施例拟合的Q值的偏差关系可以包括：水平关系和竖直关系。即偏差关系包括发射线圈和接收线圈之间径向的水平关系以及发射线圈所在平面和接收线圈所在平面之间的竖直关系。另外，在其他可能的实现方式中，Q值的偏差关系也可以仅包括竖直关系。
下面介绍控制器利用电子设备参数和无线充电设备参数拟合水平关系和竖直关系的三种具体实现方式。
第一种：
偏差关系包括：水平关系和竖直关系；其中电子设备参数包括所述发射线圈和所述接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12；
控制器，具体用于根据Q11、f11、Q12和f12拟合Q值相对于位置空间的水平关系；
根据f0、Q0、Q11和f11拟合Q值相对于位置空间的竖直关系；
或，根据f0、Q0、Q12和f12拟合Q值相对于位置空间的竖直关系；
或，根据Q0、f0和水平关系中的至少一个点对应的Q和f拟合Q值相对于位置空间的竖直关系；此种情况需要先拟合出Q值相对于位置空间的水平关系，然后根据水平关系中Q和f的对应关系提供一组Q和f的数据，然后与Q0和f0一起作为两组数据即可拟合Q值相对于位置空间的竖直关系。
通过水平关系和竖直关系获得Q值阈值，并根据Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的交流阻抗。
第二种：
偏差关系包括：发射线圈和所述接收线圈之间径向的水平关系以及所述发射线圈所在平面和所述接收线圈所在平面之间的竖直关系；
电子设备参数还包括：所述发射线圈和所述接收线圈之间至少一个相对位置无异物时的预存耦合参数；所述预存耦合参数包括以下至少一项：所述发射线圈和所述接收线圈之间的耦合系数和互感；
控制器，具体用于根据所述f0、所述Q0以及所述发射线圈和所述接收线圈之间至少一个相对位置的Q1值和f1拟合Q值相对于位置空间的所述竖直关系；根据所述预存耦合参数和所述发射线圈和所述接收线圈之间至少一个相对位置的Q1值拟合Q值相对于位置空间的水平关系；通过所述竖直关系和所述水平关系获得Q值阈值，并根据Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的所述交流阻抗。
第二种与第一种的区别是，第二种在拟合水平关系时利用了接收端的预存耦合参数。由于第二种拟合的水平关系利用了预存耦合参数，因此后续使用偏差关系时可以利用在线检测的耦合参数通过该偏差关系获得对应的水平相对位置，即耦合参数与水平关系存在单调性，例如利用在线测试的耦合系数k通过偏差关系获得对应的水平相对位置，又由于水平相对位置与Q值存在单调关系，因此可以获得对应的Q值阈值。另外，也可以直接根据k与水平关系的单调性来获得Q值阈值，因此拟合的水平关系就是Q值相对于空间的水平单调关系。
第三种：
偏差关系包括：所述发射线圈和所述接收线圈之间径向的水平关系以及所述发射线圈所在平面和所述接收线圈所在平面之间的竖直关系；
其中电子设备参数包括发射线圈和所述接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12。
电子设备参数还包括：第一位置的预存耦合参数和第二位置的预存耦合参数；预存耦合参数包括以下至少一项：发射线圈和所述接收线圈之间的耦合系数和互感；
控制器，具体用于根据所述Q11、所述Q12、所述第一位置的预存耦合参数和所述第二位置的预存耦合参数拟合Q值相对于位置空间的所述水平关系；
通过以下任一方式拟合Q值相对于位置空间的所述竖直关系：根据所述f0、所述Q0、 所述Q11和所述f11；或，根据所述f0、所述Q0、所述Q12和所述f12拟合Q值相对于位置空间的所述竖直关系；或，根据所述Q0、所述f0和所述水平关系中的至少一个点对应的Q和f拟合Q值相对于位置空间的所述竖直关系；通过所述竖直关系和所述水平关系获得所述Q值阈值，并根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的所述交流阻抗。
第三种方式与第二种方式相同的是在拟合水平关系时均利用了电子设备参数中的预存耦合参数。但是，第三种方式与第二种方式的不同是，第二种方式电子设备参数包括的是至少一个位置的，仅利用一个位置的预存耦合参数也可以拟合水平关系。第三种方式电子设备参数是包括至少两个位置的，即利用两个不同位置的预存耦合参数和两个不同位置的Q和f来拟合水平关系。由于第三种方式拟合水平关系时利用的参数较多，因此，第三种方式拟合出的水平关系更准确。
由于第三种拟合的水平关系利用了预存耦合参数，因此后续使用偏差关系时可以利用在线检测的耦合参数通过该偏差关系获得对应的水平相对位置，即耦合参数与水平关系存在单调性，例如利用在线测试的耦合系数k通过偏差关系获得对应的水平相对位置，又由于水平相对位置与Q值存在单调关系，因此可以获得对应的Q值阈值。另外，也可以直接根据k与水平关系的单调性来获得Q值阈值，因此拟合的水平关系就是Q值相对于空间的水平单调关系。
当发射线圈和接收线圈之间的水平相对位置不存在偏差，即对正时，则不需要拟合水平关系，仅拟合偏差关系中的竖直关系即可。此时，只需要接收端在一个位置的参数即可。
偏差关系包括：发射线圈所在平面和所述接收线圈所在平面之间的竖直关系；
控制器根据f0、Q0以及电子设备参数中的Q1值和f1拟合竖直关系；通过竖直关系获得Q值阈值和交流阻抗。
下面介绍控制器利用电子设备参数和无线充电设备参数拟合竖直关系的具体实现方式。
第四种
偏差关系包括：竖直关系；其中电子设备参数包括以下至少一个位置的Q1值和f1。
控制器，具体用于根据所述f0、所述Q0以及所述Q1值和所述f1拟合Q值相对于位置空间的所述竖直关系；通过所述竖直关系获得所述Q值阈值，并根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的所述交流阻抗。
当偏差关系仅包括竖直关系时，尤其适用于在水平相对位置的偏差较小，例如水平相对位置偏差<4mm时，可以不关注水平相对位置的偏差对于异物检测的精度影响，而仅考虑竖直相对位置对于异物检测精度的影响即可。例如，无线充电设备具备自动对位功能，控制器可以控制发射线圈移动进而与接收线圈对正，当对正后，发射线圈与接收线圈之间的水平相对位置可忽略不计时，仅利用第四种拟合偏差关系即可，利用偏差关系进行后续的异物检测也可以保证异物检测结果的准确性。
需要说明的是，以上介绍的无线充电设备获得偏差关系的过程是为了进行异物检测的预备过程。
在进行异物检测时，均可以利用以上四种拟合的竖直关系，即控制器，具体用于根据 无线充电设备和电子设备在当前位置的谐振频率或发射线圈的自感通过竖直关系获得Q值阈值和交流阻抗。即利用f或L1通过拟合的竖直关系来获得用于异物检测Q值阈值和交流阻抗。因为f和L1之间可以换算，存在转换关系，因此，利用f也可以，利用L1也可以。
本申请实施例提供的无线充电设备，可以根据无线充电设备参数和电子设备参数拟合出整个空间的偏差关系，从而实现整个空间的Q值与相对位置的线性化过程，不必存储Q值与整个空间的对应数据。另外，该偏差关系由于需要利用电子设备参数，即依赖于电子设备发送的参数。对于不同的电子设备，发送给无线充电设备的电子设备参数可能不同，因此，对于不同的电子设备，无线充电设备拟合的偏差关系可能不同，因此，本申请实施例提供的无线充电设备可以实现对于不同电子设备的普适性，即拟合的偏差关系实现了不同电子设备的归一化。
该无线充电设备不必对应不同的电子设备存储不同的参数，直接利用对应的电子设备发送的电子设备参数进行拟合，即可表征该电子设备的特性，使拟合出的偏差关系可以代表无线充电设备与该电子设备之间的位置偏差。而且第二种和第二种拟合方式利用了电子设备参数中的预存耦合参数，利用预存的耦合参数拟合得到的水平关系将更加精确，在使用拟合的水平关系获得Q值阈值和交流阻抗时，可以获得更准确的Q值阈值和交流阻抗，从而提高无线充电异物检测的准确度。
以上各个拟合偏差关系的方式适用于各种类型的无线充电设备，例如具有自动对位功能的无线充电设备，也适用于具有机械卡位功能的无线充电设备，也适用于具有磁吸对位功能的无线充电设备。
以上实施例介绍的仅是利用无线充电设备参数和电子设备参数拟合Q值相对整个位置空间的偏差关系，下面介绍在该偏差关系已经获得的情况下，利用当前位置通过偏差关系获得Q值阈值的过程。当前位置可以包括水平相对位置和竖直相对位置，其中，可以根据L1和和竖直相对位置的单调关系以及耦合参数与水平相对位置的单调关系来分别获得，下面介绍获得耦合参数的几种实现方式。需要说明的是，以上拟合偏差关系时利用的耦合参数是电子设备参数中包括的，即是电子设备预存的耦合参数，以下介绍的是无线充电设备在电子设备在位时即在与某一个电子设备耦合时，在线测试获取的耦合参数。
首先介绍不必对位，直接根据当前位置获得对应的Q值阈值和交流阻抗进行异物检测的过程。本实施例适用于无线充电设备不具备自动对位功能，也可以适用于无线充电设备具备自动对位功能，例如发射线圈可以自动移位，从而与电子设备中的接收线圈对正。
本实施例介绍具体的异物检测过程，无线充电设备和电子设备进行电磁耦合后，可以在线获得发射线圈的自感L1，无线充电设备和电子设备之间的耦合参数，其中耦合参数包括：耦合系数k以及互感M，其中k和M均代表无线充电设备和电子设备之间的耦合关系。
控制器根据f或L1通过偏差关系获得无线充电设备和电子设备当前相对位置对应的Q值阈值，根据当前相对位置对应的Q值阈值进行Q值异物检测；根据当前相对位置对应的Q值阈值获得当前相对位置的交流阻抗，根据当前相对位置的交流阻抗进行Ploss异物检测。
首先介绍，利用竖直关系得到Q值阈值的过程。
在上述拟合得到的竖直关系以后，可以依据在线测试的谐振频率f或发射线圈自感L 通过拟合得到的竖直关系获得Q值阈值和交流阻抗。
由于f与竖直关系存在对应关系，因此，控制器可以根据无线充电设备和电子设备在当前位置的谐振频率f或发射线圈的自感L1通过竖直关系获得Q值阈值和交流阻抗。
下面介绍无线充电设备获得发射线圈自感L1和f的过程。
参见图7，该图为本申请实施例提供的发射线圈的自感L1与相对位置的关系示意图。
其中，横坐标为水平相对位置(单位：毫米)，纵坐标为竖直相对位置(单位：毫米)。
图中曲线I1-I4分别为发射线圈的自感为6.8uH、7.2uH、7.6uH和8.0uH的等势线。
从图7可以看出，发射线圈的自感随水平相对位置的变化较小，随竖直相对位置的变化较大，因此，可以通过发射线圈的自感获取竖直相对位置。
控制器32，还用于根据发射端谐振网络的谐振频率和发射端谐振网络的谐振电容获得发射线圈的自感。
可以通过如下计算公式获取发射线圈的自感L1：
Figure PCTCN2021110254-appb-000002
其中，C1为谐振网络的电容且已知，例如预存在无线充电设备中，L1为发射线圈的自感，f为谐振频率。
继续参见图5，控制器32判断全桥逆变电路达到稳定状态后，关断S1，开启S2。C1存储的能量会在L1、C1形成的谐振电路、及S2和S4构成的回路中释放，通过检测C1和L1之间的电压变化，获得电压振荡曲线，通过电压振荡曲线即可得到谐振频率f。
根据发射线圈的自感可以通过图7对应的单调关系获得自感对应的竖直相对位置。由于拟合得到的竖直关系表征的是Q值阈值与竖直相对位置的关系，因此，由L1获得的竖直相对位置可以通过竖直关系获得对应的Q值阈值，为了更简便，也可以在竖直关系中直接包括L1与Q值阈值的对应关系，或者直接包括f与Q值阈值的对应关系，可以根据在线测试的f或L1直接通过查找拟合的竖直关系便可以得到对应的Q值阈值，进而得到交流阻抗。
以上介绍的是一种利用竖直关系获得Q值阈值的过程，下面介绍当偏差关系包括水平关系和竖直关系时，获得Q值阈值的过程，应该理解，获得Q值阈值之后可以获得交流阻抗。
下面介绍四种通过在线测试的耦合参数和L1(其中L1也可以为f，因为L1与f存在以上公式所示的转换关系，下面以L1为例进行介绍)通过已经拟合得到的偏差关系获得Q值阈值的方式。即控制器还用于获得无线充电设备和电子设备耦合状态下的耦合参数和发射线圈的自感L1；耦合状态下的耦合参数包括以下至少一项：耦合系数和互感；根据耦合状态下的耦合参数和L1通过偏差关系获得Q值阈值和交流阻抗；耦合状态下的耦合参数与水平关系存在单调关系，L1与竖直关系存在单调关系。
第一种：
控制器还用于接收电子设备发送的耦合状态下接收线圈的自感L2；根据所述发射线圈的电流、耦合状态下发射线圈的自感L1、所述L2和所述接收线圈对应的整流电压获得耦合参数；
控制器获得耦合参数以后，再根据耦合参数和所述L1通过所述偏差关系获得所述Q值阈值和所述交流阻抗。
第二种：
控制器还用于接收电子设备发送的非耦合状态下接收线圈的自感L20；根据耦合状态下发射线圈的自感L1、非耦合状态下发射线圈的自感L10、所述L20获得耦合状态下接收线圈的自感L2，根据所述L1、所述L2和所述接收线圈对应的整流电压获得耦合参数；
控制器获得耦合参数以后，再根据耦合参数和所述L1通过所述偏差关系获得所述Q值阈值和所述交流阻抗。
对于第一种和第二种情况，即电子设备参数还可以包括：非耦合状态下接收线圈的自感L20或耦合状态下接收线圈的自感L2。当电子设备参数还包括L20时，控制器32可以依据L20获得L2。具体地，控制器32还用于根据L20获得耦合状态下接收线圈的自感L2。一般情况下，发射线圈的自感和接收线圈的自感存在预设的比例关系。例如，控制器32根据发射端在非耦合状态下发射线圈的自感L10、耦合状态下发射线圈的自感L1、L20和预设的比例关系可以获得耦合状态下接收线圈的自感L2。对于这种情况，接收端无需获得L2，仅获得L20即可。
第三种：
控制器还用于接收电子设备发送的耦合状态下辅助线圈的自感L3；根据所述发射线圈的电流、耦合状态下发射线圈的自感L1、所述L3和所述辅助线圈对应的整流电压获得耦合参数；
控制器获得耦合参数以后，再根据耦合参数和所述L1通过所述偏差关系获得所述Q值阈值和所述交流阻抗。
第四种：
控制器还用于接收电子设备发送的非耦合状态下辅助线圈的自感L30；根据耦合状态下发射线圈的自感L1、非耦合状态下发射线圈的自感L10、所述L30获得耦合状态下辅助线圈的自感L3，根据所述L1、所述L3和所述辅助线圈对应的整流电压获得耦合参数；
控制器获得耦合参数以后，再根据耦合参数和所述L1通过所述偏差关系获得所述Q值阈值和所述交流阻抗。
对于第三种即电子设备参数还包括：耦合状态下辅助线圈的自感L3或和第四种情况即电子设备参数还包括：非耦合状态下辅助线圈的自感L30；控制器，还用于根据发射线圈的自感和所述L30获得耦合状态下辅助线圈的自感L3；一般情况下，发射线圈的自感和辅助线圈的自感存在预设的比例关系。因此，控制器根据非耦合状态下发射线圈的自感L10、耦合状态下发射线圈的自感L1、L30和预设的比例关系可以获得耦合状态下辅助线圈的自感L3。对于这种情况，接收端无需获得L3，即获得L30即可。
需要说明的是，以上四种获得耦合参数的方式，均是在线获得的，而无线充电设备实施例一中的电子设备参数包括的预存耦合参数是电子设备预存的，例如是手机预存的。以上介绍的是获得耦合参数的方式，当电子设备包括辅助线圈时，可以获得发射线圈与辅助线圈之间的耦合参数，也可以获得发射线圈和接收线圈之间的耦合参数。但是，当电子设 备没有辅助线圈时，只能获得发射线圈与接收线圈之间的耦合参数。
下面具体介绍获得发射线圈和接收线圈之间的耦合参数的方式。
参见图8，该图为本申请实施例提供的耦合系数k与相对位置的关系示意图。
其中，横坐标为水平相对位置(单位：毫米)，纵坐标为竖直相对位置(单位：毫米)，图中虚线L和虚线K分别为同一相对位置时获得的发射线圈的自感以及发射线圈和接收线圈之间的耦合系数。
从图8可以看出，发射线圈和接收线圈之间的耦合系数随竖直相对位置的变化较小，随水平相对位置的变化较大。并且，发射线圈和接收线圈之间的耦合系数与水平相对位置负相关，即水平相对位置越大，发射线圈和接收线圈之间的耦合系数越小。因此，可以通过获得发射线圈和接收线圈之间的耦合系数获得水平相对位置。
参见图9，该图为本申请实施例提供的互感M与相对位置的关系示意图。
其中，横坐标为水平相对位置(单位：毫米)，纵坐标为竖直相对位置(单位：毫米)。从图9可以看出，发射线圈和接收线圈之间的线圈互感随竖直相对位置的变化较小，随水平相对位置的变化较大。发射线圈和接收线圈之间的线圈互感与水平相对位置负相关，即水平相对位置越大，发射线圈和接收线圈之间的线圈互感越小。因此，可以通过获得发射线圈和接收线圈之间的线圈互感来获得水平相对位置。
以上根据L1获得竖直相对位置，根据k或M获得水平相对位置，因此，根据竖直相对位置和水平相对位置通过偏差关系便可以获得对应的Q值阈值，例如通过图5，当竖直相对位置和水平相对位置已知时，可以唯一确定对应的Q值。
下面介绍获得k或M的具体过程。
发射线圈和接收线圈之间的耦合系数可以通过以下公式(2)获得：
Figure PCTCN2021110254-appb-000003
其中，L1为发射线圈的自感，L2为接收线圈的自感，控制图6中的全桥逆变电路处在逆变工作状态，ω为工作频率且已知，电子设备的接收端处于空载状态，测量整流后的电压Vrect，以及此时发射线圈的电流I1。
发射线圈和接收线圈之间的互感M可以通过以下公式(3)获得：
Figure PCTCN2021110254-appb-000004
其中，V rect为接收端整流电路输出的直流电压，I1为发射线圈的电流，ω为工作频率且已知，α为系数且可以通过实验得到。
以上介绍的是发射线圈与接收线圈之间的k和M的获取方式，下面介绍发射线圈与辅助线圈之间的k和M的获取方式。当接收端既包括接收线圈又包括辅助线圈时，可以利用辅助线圈与发射线圈之间的耦合参数来获得相对位置，也可以利用接收线圈与发射线圈之间的耦合参数来获得相对位置，其中耦合参数包括k或M，即利用k也行，利用M也行，k和M均可以表征发射端与接收端之间的耦合关系。并且，k和M均与水平相对位置存在单调关系。
参见图10，该图为本申请实施例提供的一种无线充电系统的示意图。
电子设备包括接收线圈L2、辅助线圈L3第一整流器21a和第二整流器21b，L2 的第一端通过C2连接第一整流器21a的正输入端，L2的第二端连接第一整流器21a的负输入端。第一整流器21a的输出端用于连接后级充电电路，后级充电电路用于为电子设备中的电池进行充电。实质是L2和C2串联后连接在第一整流器21a的输入端。
辅助线圈L3和电容C3串联后连接第二整流器21b的输入端。
控制器控制发射端的全桥逆变电路处于逆变工作的状态，控制接收端处于空载状态，获得辅助线圈的直流输出电压和发射线圈的电流，根据发射线圈的电流、辅助线圈的直流输出电压，以及工作频率、发射线圈的自感和辅助线圈的自感获得至少一项参数中的耦合系数，可以通过如下计算公式(4)获得发射线圈和辅助线圈之间的耦合系数：
Figure PCTCN2021110254-appb-000005
其中，V ac3为辅助线圈的直流输出电压，I 1为发射线圈的电流，ω为工作频率且已知，L1发射线圈的自感，L3辅助线圈的自感。
控制器200获得发射线圈和辅助线圈之间的耦合系数后，根据接收端处于空载状态时对应的发射线圈电流、辅助线圈的直流输出电压，以及工作频率获得至少一项参数中的线圈互感，可以通过如下计算公式(5)获得发射线圈和辅助线圈之间的线圈互感M 2：
Figure PCTCN2021110254-appb-000006
其中，V ac3为辅助线圈的直流输出电压，I1为发射线圈的电流，ω为工作频率且已知。
上述发射线圈和辅助线圈之间的耦合系数的计算公式中，β可以通过实验测得，本领域技术人员还可以为了进一步提高检测耦合系数的准确度，对β的数值进行修正。
由于以上获得k和M时需要使用发射线圈的电流，因此，下面介绍获得发射线圈的电流的方式。
可以理解的是，图6中发射端的逆变电路是以全桥逆变电路为例进行的介绍。
为了在逆变电路为全桥电路时，更准确地获得发射线圈的电流，本申请实施例提供了一种电路检测电路。
参见图11，该图为本申请实施例提供的一种发射线圈的电流的检测电路图。
本实施例提供的无线充电设备还包括：发射线圈的电流检测电路；
所述电流检测电路，用于检测所述谐振电容两端的电压差；例如检测谐振电路的第一端的电压和第二端的电压，获得第一端的电压和第二端的电压的差值，即电压差。
控制器，用于根据电压差获得发射线圈的电流。对于谐振电容来说，谐振电容的电流为：i＝cdu/dt，因此，获得谐振电容两端的电压差，再对电压差求微分获得电流更符合物理原理。
具体地，电流检测电路包括：第一电压检测电路1001、第二电压检测电路1002和差分电路1003；
所述第一电压检测电路1001，用于检测所述谐振电容C1的第一端的第一电压，将所述第一电压分压后发送给所述差分电路1003的第一输入端；
所述第二电压检测电路1002，用于检测所述谐振电容C1的第二端的第二电压，将所述第二电压分压后发送给所述差分电路1003的第二输入端；
所述差分电路1003，用于获得所述第一输入端输入的电压和所述第二输入端输入的电压的差分结果；
所述控制器32，用于根据所述差分结果获得所述发射线圈L1的电流。
由于L1与C1串联，因此，流过L1的电流与流过C1的电流相等。
另外，实际实现时，逆变电路也可以利用半桥电路来实现，下面介绍半桥电路对应的发射线圈的电流的获得过程。
参见图12，该图为本申请实施例提供的另一种发射线圈的电流的检测电路图。
本实施例提供的半桥逆变电路对应的发射线圈的电流检测电路包括：分压电路1101、比例放大电路1102；
其中分压电路1101检测谐振电容C1的一端的电压，将该电压进行分压后发送给比例放大电路1102的输入端；
比例放大电路1102用于将输入电压进行比例放大后发送给控制器32。
由于图12对应的逆变电路为半桥电路，因此，可以检测谐振电容C1一端的电压，而不必检测两端的电压进行差分。
可以理解的是，图11和图12中的控制器32可以自带模数转换功能，即模拟信号的电压直接输入控制器32的引脚，当控制器32不自带模数转换功能时，在控制器32的引脚之前还可以连接一级模数转换器，模数转换器将模拟信号转换为数字信号后，再发送给控制器32的引脚。
下面介绍利用交流阻抗进行Ploss异物检测过程。
Ploss法：
功率损耗为发射功率和接收功率之间的功率差，可以通过如下公式计算：
P loss＝P tx-P rx     (6)
其中，P loss为功率损耗，P tx为发射功率，发射功率为发射端发射的磁场能量，P rx为接收功率，接收功率为电子设备接收端接收的磁场能量。
发射功率P tx可以通过如下公式(6)计算：
P tx＝P in-P tx loss     (7)
其中，P in为发射端的输入功率，P tx loss为发射端的功率损耗，包括发射端的电路的损耗和发射线圈的损耗。
接收功率P rx可以通过如下公式计算：
P rx＝P out+P rx loss     (8)
其中，P out为接收端的输出功率，P rx loss为接收端的功率损耗，包括接收端的电路的损耗和接收线圈的损耗。
本申请实施例提供的方式是将根据上述拟合的偏差关系确定的交流阻抗引入到P tx loss、P rx loss的计算中，进而使得P tx、P rx计算的结果更精确，从而使得P loss更精确，提高Ploss异物检测的精度，可以支持更大功率的无线充电。
无线充电设备的功率损耗可以表达如下公式(9)：
P tx loss＝f(Vin)+f(TxACR,I1)       (9)
其中：
Vin为逆变电路的母线电压；
TxACR指的是在发射线圈与接收线圈在某个相对位置下对应的发射线圈的交流阻抗ACR；
I1为发射线圈的电流；
f(TxACR,I1)＝(a+TxACR)*I1 2+b*I1+c     (10)
或者进一步地：
f(TxACR,I1)＝(a+TxACR*d)*I1 2+b*I1+c      (11)
可以得知，以上公式(10)和(11)均是一元二次函数，其中的系数a、b、c、d对于一个发射端可以预先通过测试获得，即为已知数值。
以上公式(10)和(11)为获得发射端的功率损耗的方式，可以理解，接收端的功率损耗P rx loss的获得也可以参考以上发射端对应的公式来获得。例如，实际获得时可以控制接收端工作在发射端的状态，预先测试获得上述公式中对应的各个系数。
另外，为了异物检测更准确，本申请实施例还提供了另外一种进行Ploss异物检测的方式，具体利用k和交流阻抗TxACR进行异物检测，下面进行详细说明。
当无线充电设备可以在线测试获得耦合系数k时，还可以进一步根据交流阻抗、在线测试的耦合系数k进行Ploss异物检测。
P tx loss＝f(Vin)+f(TxACR,k,I1)      (12)
其中：
k为发射线圈与接收线圈之间的耦合系数；
f(TxACR,k,I1)＝(a+TxACR*f(k))*I1 2+b*I1+c      (13)
上述系数a、b、c对于一个发射端而言，可以预先通过实验获得。
进一步地：f(k)可以为关于耦合系数k的一元一次函数，也可以为关于耦合系数k的一元二次函数；上述一元一次函数及一元二次函数的系数均可以预先通过实验获得。
实际应用中，获得耦合系数k后，便可以在线精确计算当前耦合系数k对应的系数d，从而进一步提高P tx loss、P rx loss的计算精度，精度越高，则可以对应适用的无线充电的功率越大，因此可以支持更大功率的无线充电。
接收端P rx loss的计算类似于发射端。实际应用时，可以控制接收端工作在发射端状态，预先测得上述公式中的各个系数。
一般情况下，发射端的功耗在无线充电系统的功耗中占主要比重，因此在实际产品中，一般可以只对发射端的功耗采用上述精确的算法计算P tx loss；接收端可以不需要采用上述精确算法计算P rx loss。应该理解，接收端的功耗的精确算法与发射端的功耗的精确算法类似，具体如下：
P rx loss＝f(Vout)+f(RxACR,I2)    (14)
P rx loss＝f(Vout)+f(RxACR,k,I2)       (15)
其中：
Vout为整流电路的母线电压；
RxACR为发射线圈与接收线圈在某个相对位置时接收线圈的交流阻抗ACR；
I2为接收线圈的电流；
耦合系数k为发射线圈与接收线圈之间的耦合系数；
接收端可以采用如下的简单公式：
P rx loss＝f(Vout)+f(非耦合状态下的RxACR,I2)      (16)
其中：
非耦合状态下的RxACR为接收线圈单独放置、离发射线圈足够远的情况下接收线圈的ACR，即发射线圈和接收线圈未耦合时对应的接收线圈的ACR。
f(非耦合状态下的RxACR,I2)＝(a+非耦合状态下的RxACR)*I2 2+b*I2+c
上述系数a、b、c对于一个接收端，可以预先通过实验得到。
通过以上分析可知，本申请实施例提供的Ploss异物检测的方法，除了利用交流阻抗以外，还加入了耦合系数k，即在异物检测时，功率损耗的获取通过利用交流阻抗和耦合系数的函数来获得，加入耦合系数以后可以使得计算的功率损耗更精确，从而可以适用于更大功率的无线充电的异物检测。以上各种获得耦合参数的方式适用于各种类型的无线充电设备，并且，利用交流阻抗和在线测试的耦合参数进行异物检测也适用于各种类型的无线充电设备。例如具有自动对位功能的无线充电设备，也适用于具有机械卡位功能的无线充电设备，也适用于具有磁吸对位功能的无线充电设备。
以上实施例提供的技术方案可以适用于具有自动对位功能的无线充电设备，也可以适用于不具备自动对位功能的无线充电设备，下面介绍具有对位功能的无线充电设备，具有对位功能的无线充电设备，可以为具有自动对位的无线充电设备，即无线充电设备的控制器通过水平相对位置，可以控制发射线圈移动，使其与接收线圈自动实现对位。无线充电设备也可以不具有自动对位功能，即可以通过机械卡位或磁吸对位实现对正。
下面首先介绍无线充电设备具有自动对位功能，控制器可以控制发射线圈的对正过程，以及对正后再利用偏差关系获得对正后的Q值阈值和交流阻抗进行异物检测的原理。
无线充电设备实施例三：
参见图13，该图为本申请实施例提供的另一种无线充电设备的示意图。
本实施例提供的无线充电设备还包括对位机构33。
控制器32根据所述发射线圈的移动方向控制对位机构33驱动所述发射线圈沿着所述移动方向移动。
对位机构的一种实现方式是，对位机构至少包括：第一马达、第二马达、第一导轨和第二导轨；
第一导轨和所述第二导轨相互垂直；
第一马达，用于驱动所述发射线圈沿着所述第一导轨运动；
第二马达，用于驱动所述发射线圈沿着所述第二导轨运动；
控制器用于控制所述第一马达和所述第二马达，以使所述发射线圈沿着所述移动方向移动。
参见图14，该图为本申请实施例提供的一种对位结构的示意图。
图14中的x和y分别表示水平面上的两个互相垂直的方向，例如x表示水平方向，则y表示与水平方向垂直的方向，单位均为毫米mm。
当发射线圈和接收线圈位于不可通讯区域时，只能利用发射线圈的自感L1进行发射线圈与接收线圈之间相对位置判断。
如图14所示，随着无线充电设备与电子设备之间相对位置的变化，发射线圈的自感L1随之变化，总体上呈现在同一水平面上，发射线圈的自感L1随着位置偏差的增大而呈现下降的趋势，例如，x和y的坐标均为0时，对应的L1为7.8uH，x和y均为5mm时，对应的L1为7.65uH，即位置偏差越大则L1越小，即L1与位置偏差成负相关的关系。
参见图15，该图为本申请实施例提供的一种发射线圈的对位原理示意图。
本实施例提供的无线充电设备中的控制器，还用于获得两个不同位置的所述发射线圈的自感和以下至少一项耦合参数，所述耦合参数包括：耦合系数和互感；根据所述发射线圈的自感和所述至少一项耦合参数确定所述发射线圈和接收线圈之间的水平相对位置和竖直相对位置，根据所述水平相对位置移动所述发射线圈，使所述发射线圈与所述接收线圈对正。
发射线圈的自感与所述竖直相对位置存在第一单调关系，所述至少一项耦合参数与所述水平相对位置存在第二单调关系。具体可以参见图7、图8和图9。
为了方便描述，下面以测量发射线圈的自感，以及，发射线圈与接收线圈之间的耦合系数k为例进行说明。同理，也可以测量发射线圈与辅助线圈之间的耦合系数。其中耦合系数均可以替换为互感M。
本申请实施例提供的对位方式，测量两个不同位置的发射线圈的自感L1和耦合系数k便可以确定接收线圈的位置。下面结合图15来说明。
测量的两个位置分为O1和O2，即发射线圈的中心在O1，然后移动到O2。
首先，在O1时，获得发射线圈的自感L1和耦合系数k，根据O1点处测量的L1和k获得发射线圈和接收线圈之间的水平相对位置以及竖直相对位置。根据水平相对位置获得发射线圈在O1与发射线圈的径向距离为r1。
其次，移动发射线圈的中心到O2，在位置O2测量L1和k后，根据O2点处测量的L1和k获得发射线圈和接收线圈之间的竖直相对位置和水平相对位置。根据水平相对位置获得发射线圈在O2与接收线圈的径向距离r2。
如图15所示，O1为圆心r1为半径的圆周与O2为圆心r2为半径的圆周相交的两点中的一个为接收线圈的中心，即RX(A)或RX(B)。
即无线充电设备的控制器，具体用于获得两个不同位置(O1和O2)对应的两个水平相对位置(r1和r2)分别为半径的第一圆周和第二圆周，获得所述第一圆周和所述第二圆周的交叉点，即RX(A)或RX(B)，控制发射线圈对正至所述交叉点。
由于接收线圈的中心可能位于RX(A)，也可能位于RX(B)，则需要控制器控制发射线圈再进行移动，移动过程中可以获得耦合系数，例如根据耦合系数的变化趋势，判断接收线圈的中心对应RX(A)，还是对应RX(B)。即控制器，还用于移动发射线圈到第三位置，第三位置区别于两个不同位置(即第三位置与O1和O2可以不同)；获得移动过程中的以下至少一项参数，根据至少一项参数的变化趋势确定发射线圈对正至的交叉点；其中，至少一项参数包括：耦合参数、充电效率、所述发射线圈的自感、所述发射线圈的电流和所述接收端的输出电压。由于以上至少一项参数均与水平相对位置存在单调关系，因此，可以在移动过程中获得以上任意一项或多项参数的变化趋势，根据变化趋势和单调关系确定接收线圈的中心为RX(A)，还是RX(B)。
可以理解的是，为了简单方便易于实现，可以边移动边测量以上参数，也可以移动到一个固定位置再测量，本申请实施例中不作具体限定，测量的位置的数量越少，参数越少，则控制和计算越简单，易于实现。最简单的一种是测量三个不同位置的参数便可以确定接收线圈的中心位置。控制器获得接收线圈的中心位置以后，可以控制发射线圈进行移动， 使发射线圈与接收线圈进行对正。
需要说明的是，另一种特殊情况是，当r1和r2相等时，移动的位置又可能使r1和r2对应的两个圆周相切，即两个圆周仅存在一个交点，此时相切的点即为接收线圈的中心。
由于实际应用中，实际的测量误差、马达等机械结构的移动精度等引起的水平对位偏差，尤其是不同手机型号以及手机壳引起的竖直高度不同，对位后的发射线圈与接收线圈有可能继续存在位置偏差，因此，还需要再次测量对正后的L1和k，根据L1和k获得对正后的发射线圈与接收线圈之间的水平相对位置和竖直相对位置，根据水平相对位置和竖直相对位置通过拟合的偏差关系获得Q值阈值和交流阻抗，进而利用Q值阈值进行Q值异物检测，利用交流阻抗进行Ploss异物检测。
需要说明的是，获得L1和k的过程具体可以参见无线充电设备实施例二的介绍，与不进行对正时获得L1和k的方式类似，在此不再赘述。
在一种可能的实现方式中，当发射线圈与接收线圈对正之后，发射线圈和接收线圈的水平相对位置较小时，即可以忽略水平偏差，仅根据拟合的竖直关系来获得对应的Q值阈值和交流阻抗即可。
本申请实施例提供的无线充电设备，控制器在检测电子设备移走之后，可以控制发射线圈移回初始位置，为了便于控制发射线圈移回初始位置，在控制发射线圈与接收线圈进行对正时，需要记录发射线圈的移动轨迹或记录发射线圈最终的位置坐标，根据移动轨迹或者发射线圈最终的位置坐标将发射线圈移回初始位置。发射线圈的初始位置为已知参数。
另外，在一种可能的实现方式中，控制器用于控制发射线圈移动到第四位置，第四位置与第一位置和第二位置不在同一直线，即三点不在同一个直线上；获得第四位置对应的发射线圈的自感与耦合参数；根据第四位置对应的发射线圈的自感和耦合参数确定水平相对位置和竖直相对位置，依据水平相对位置确定第三圆周，控制发射线圈移动至第三圆周与交叉点的公共点。
以上已经介绍无线充电设备具有对位机构的具体实现方式，下面结合附图分别介绍无线充电设备具有机械卡位和磁吸对位的具体实现方式。
参见图16，该图为本申请实施例提供的一种带有机械卡位的无线充电设备的示意图。
无线充电设备02上设置有卡位02a，应该理解本申请实施例不具体限定卡位02a的具体实现形式，卡位02a主要起限位作用。卡位02a可以为凸起，也可以为凹槽，只要可以固定电子设备01即可。当电子设备01放置在无线充电设备02上充电时，卡位02a固定住电子设备02，以免电子设备02相对于无线充电设备02移动，从而保证电子设备01与无线充电设备02之间的相对位置，实现高效率充电。
在另外一种实现方式中，无线充电设备可以具有磁吸对位功能。
参见图17，该图为本申请实施例提供的带有磁吸对位的无线充电设备的示意图。
无线充电设备02上设置有磁铁02b，本申请实施例不具体限定磁铁02b的具体位置，只要电子设备01放置在无线充电设备02上充电时，磁铁02b可以与电子设备01中的磁铁进行有效相吸，从而可以吸附电子设备01在无线充电设备02的合适位置，以帮助无线充电设备02和电子设备01之间的对正，从而提高无线充电的效率。
应该理解，对于图16和图17对应的无线充电设备，控制器不必自动控制发射线圈移动，但是可以检测发射线圈和接收线圈的对位情况。
需要说明的是，在以上任意一种发射线圈与接收线圈对正后，控制器还用于根据发射线圈的自感通过以上拟合得到的偏差关系获得Q值阈值和交流阻抗；根据Q值阈值进行Q值异物检测，根据交流阻抗和耦合参数进行Ploss异物检测。由于对正之后，已经不存在水平偏差，只存在竖直偏差，也可以仅利用拟合的竖直关系来获得Q值阈值和交流阻抗。
无线充电底座实施例一：
基于以上实施例提供的一种无线充电设备、方法及系统，本申请实施例还提供一种无线充电底座，用于为电子设备进行无线充电，例如电子设备为手机或穿戴设备。当电子设备为手机时，无线充电底座为手机充电时，无线充电底座水平放置在桌面上，手机水平放置在无线充电底座上即可，由于无线充电底座内设置发射线圈，手机中设置接收线圈，因此，发射线圈和接收线圈之间通过电磁场耦合，实现能量的传递，完成为手机的无线充电。
本实施例提供的无线充电底座，用于为电子设备进行无线充电，包括：电源接口、谐振网络、逆变电路、控制器、发射线圈底盘和对准导轨。
继续参见图1，其中无线充电底座为02，无线充电底座02的电源接口与适配器40连接，适配器40将市电转换为直流电提供给无线充电底座02。
电源接口，用于连接适配器传输的直流电；
适配器用于将交流市电转换为直流电，提供给电源接口，例如将市电交流220V转换为直流电。
谐振网络包括谐振电容和发射线圈；
发射线圈底盘，用于放置所述发射线圈；
逆变电路的输入端用于连接电源接口，逆变电路的输出端用于连接谐振网络；
控制器，用于接收所述电子设备发送的电子设备参数，根据无线充电设备参数和所述电子设备参数拟合所述无线充电设备的Q值相对于位置空间的偏差关系，所述位置空间为所述发射线圈和所述电子设备的接收线圈之间的位置空间；其中所述电子设备参数包括：所述发射线圈和所述接收线圈之间至少一个相对位置无异物时的所述无线充电设备的Q1值和所述谐振网络的谐振频率f1；所述无线充电设备参数包括：所述无线充电设备与所述电子设备非耦合状态下所述无线充电设备的的初始Q值Q0和所述谐振网络的初始谐振频率f0。
控制器，还用于根据所述偏差关系进行异物检测。
本实施例提供的无线充电底座，可以根据有限数量的无线充电设备参数和电子设备参数拟合Q值相对于整个位置空间的偏差关系，即拟合类似图5所表征的Q值相对于水平相对位置和竖直相对位置的对应关系。因此，无线充电设备无需存储整个位置空间的Q值与水平相对位置以及Q值与竖直相对位置的所有数据，从而大大降低存储空间。即控制器32利用发射线圈和接收线圈至少一个相对位置无异物时的Q1值和谐振频率f1，非耦合状态下的初始Q值Q0和初始谐振频率f0获得Q值相对于整个位置空间的偏差关系，获得Q值相对于整个位置空间的偏差关系以后，可以通过偏差关系获得当前位置对应的Q值，从 而根据Q值进行异物检测。由于Q值与发射线圈的交流阻抗存在转换关系，因此，可以由Q值获得对应的交流阻抗，即可以交流阻抗相对于整个位置空间的偏差关系便可以省略，通过Q值便可以换算得到交流阻抗，从而根据交流阻抗进行Ploss异物检测。
以上无线充电设备实施例中介绍的拟合偏差关系的方式均适用于无线充电底座，在此不再赘述，下面仅列举其中的一部分。以上实施例的优点和效果均适用于无线充电底座。
电子设备参数可以包括发射线圈和接收线圈至少一个相对位置的Q1值和f1，也可以包括至少两个相对位置的Q1值和f1，可以理解的是，相对位置越多，则对应的参数越多，越多参数参与拟合，则拟合得到的偏差关系越准确。下面以电子设备参数包括至少两个相对位置为例进行说明。其中电子设备参数包括一个相对位置的可以参考以上实施例的无线充电设备的介绍。
电子设备参数包括发射线圈和接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12。
其中一种实现方式为，偏差关系包括：发射线圈和所述接收线圈之间径向的水平关系以及所述发射线圈所在平面和所述接收线圈所在平面之间的竖直关系。
电子设备参数还包括：发射线圈和接收线圈之间至少一个相对位置无异物时的预存耦合参数；预存耦合参数包括以下至少一项：耦合系数和互感；
控制器根据f0、Q0以及至少一个相对位置的Q1值和f1拟合竖直关系；根据预存耦合参数和至少一个相对位置的Q1值拟合水平关系；通过竖直关系和水平关系获得Q值阈值和交流阻抗。
当电子设备参数包括两个位置对应的Q1值和f1值，一种拟合偏差关系的具体实现方式为，偏差关系包括：竖直关系和水平关系；
电子设备参数还包括：第一位置的预存耦合参数和第二位置的预存耦合参数；预存耦合参数包括以下至少一项：耦合系数和互感；
控制器，具体用于根据Q11、Q12、第一位置的预存耦合参数和第二位置的预存耦合参数拟合水平关系；
根据f0、Q0、Q11和f11拟合竖直关系；
或，根据f0、Q0、Q12和f12拟合竖直关系；
或，根据Q0、f0和水平关系中的至少一个点对应的Q和f拟合竖直关系；
通过竖直关系和水平关系获得Q值阈值和交流阻抗。
由于拟合的水平关系利用了预存耦合参数，因此后续使用偏差关系时可以利用在线检测的耦合参数通过该偏差关系获得对应的水平相对位置，即耦合参数与水平关系存在单调性，例如利用在线测试的耦合系数k通过偏差关系获得对应的水平相对位置，又由于水平相对位置与Q值存在单调关系，因此可以获得对应的Q值阈值。另外，也可以直接根据k与水平关系的单调性来获得Q值阈值，因此拟合的水平关系就是Q值相对于空间的水平单调关系。
在进行异物检测时，均可以利用以上拟合的竖直关系，由于谐振频率和发射线圈均与竖直相对位置存在单调关系，因此，控制器可以根据无线充电设备和电子设备在当前位置 的谐振频率或发射线圈的自感通过竖直关系获得Q值阈值和交流阻抗。即利用谐振频率f或发射线圈的自感L1通过拟合的竖直关系来获得用于异物检测Q值阈值和交流阻抗。因为f和L1之间可以换算，存在转换关系，因此，利用f也可以，利用L1也可以。
为了使异物检测的结果更准确，控制器可以根据交流阻抗和在线测试的耦合状态下的耦合参数进行Ploss异物检测。其中，耦合参数与水平相对位置存在单调关系，因此，利用耦合参数可以准确通过水平关系获得对应的交流阻抗，进而可以提高计算的功率损耗的准确性。
另外，该无线充电底座还可以包括：对位机构；控制器可以控制对位机构驱动发射线圈与接收线圈对正。具体的示意图和实现方式可以参见无线充电设备的实施例，在此不再赘述。另外，无线充电设备不具有自动对位功能时，可以包括机械卡位实现对正。另外，无线充电设备也可以包括磁吸对位实现对正。对于机械卡位和磁吸对位均可以参见以上无线充电设备实施例的描述。
对位结构至少包括对准导轨；对准导轨至少包括：在水平面的投影相互垂直的第一导轨和第二导轨；还包括：电驱动部件；电驱动部件，用于驱动发射线圈沿着第一导轨和第二导轨运动；控制器，还用于控制电驱动部件，电驱动部件驱动发射线圈与接收线圈对正。
该无线充电底座还可以具有自动对位的功能，即控制器，还用于获得两个不同位置的发射线圈的自感和以下至少一项耦合参数，耦合参数包括：耦合系数和互感；根据发射线圈的自感和至少一项耦合参数确定发射线圈和接收线圈之间的水平相对位置和竖直相对位置，根据水平相对位置移动发射线圈，使发射线圈与接收线圈对正；
发射线圈的自感与竖直相对位置存在第一单调关系，至少一项耦合参数与水平相对位置存在第二单调关系。
具体可以参见无线充电设备的实施例三中描述的发射线圈对正的内容，在此不再赘述。其中该无线充电底座可以包括图13和图14对应的对位机构，控制器控制该对位机构使发射线圈与接收线圈实现对正。
基于以上实施例提供的一种无线充电设备以及无线充电底座，本申请实施例还提供一种无线充电的异物检测方法，下面结合附图进行详细介绍。
异物检测方法实施例一：
参见图18，该图为本申请实施例提供的一种无线充电的异物检测方法的流程图。
本实施例提供的无线充电的异物检测方法，应用于无线充电设备，无线充电设备包括：谐振网络和逆变电路；谐振网络包括谐振电容和发射线圈；逆变电路的输入端用于连接直流电源，逆变电路的输出端用于连接谐振网络；
该方法包括以下步骤：
S1601：接收电子设备发送的电子设备参数；电子设备参数包括：发射线圈和接收线圈至少一个相对位置无异物时的Q1值和谐振频率f1；
电子设备参数是电子设备预存的初始参数，例如电子设备为手机，可以为手机出厂时即预存的参数。电子设备参数包括：至少一个相对位置无异物时的Q1值和谐振频率f1。至少一个相对位置是指无线充电设备和电子设备之间的相对位置，一般以发射线圈和接收 线圈之间的相对位置为准。例如可以为一个相对位置下对应的参数，也可以为两个位置下对应的参数，也可以为多个位置下对应的参数，可以理解的是，相对位置越多，对应的参数越多，则拟合出来的偏差关系越准确。例如，两个相对位置无异物时的Q1值是指手机相对于无线充电器两个不同位置时，手机测得的Q1值，而两个位置无异物时的谐振频率f1是指手机相对于无线充电器两个不同位置时，无线充电器的谐振网络的谐振频率f1。
无线充电设备参数是无线充电设备预存的参数，例如无线充电器预存的参数。无线充电设备参数包括：无线充电设备与电子设备非耦合状态下的初始Q值Q0和初始谐振频率f0。非耦合状态是指无线充电设备和电子设备的距离较远，还没有进行电磁耦合。即对于无线充电器，还检测不到手机时的无线充电器的Q0和f0。
S1602：根据电子设备参数和无线充电设备参数拟合Q值相对于位置空间的偏差关系；无线充电设备参数包括：无线充电设备与电子设备非耦合状态下的初始Q值Q0和初始谐振频率f0；
需要说明的是，偏差关系可以为一次函数也可以为多次函数，本申请实施例具体不限定拟合的方式，根据多个已知参数，可以拟合出Q值相对于空间的偏差关系。
S1603：根据偏差关系获得Q值阈值进行Q值异物检测，根据Q值阈值以及Q值与发射线圈的交流阻抗的对应关系获得对应的交流阻抗，根据获得交流阻抗进行Ploss异物检测。
本申请实施例提供的无线充电设备的控制器32可以根据有限数量的无线充电设备参数和电子设备参数拟合Q值相对于整个位置空间的偏差关系，即拟合类似图5所表征的Q值相对于水平相对位置和竖直相对位置的对应关系。因此，无线充电设备不需存储整个位置空间的Q值与水平相对位置以及Q值与竖直相对位置的所有数据，从而大大降低存储空间。即控制器32利用至少一个相对位置无异物时的Q1值和谐振频率f1，非耦合状态下的初始Q值Q0和初始谐振频率f0获得Q值相对于整个位置空间的偏差关系，获得Q值相对于整个位置空间的偏差关系以后，可以通过偏差关系获得当前位置对应的Q值，从而根据Q值进行异物检测。由于Q值与发射线圈的交流阻抗存在公式(1)所示的关系，因此，可以由Q值获得对应的交流阻抗，即交流阻抗相对于整个位置空间的偏差关系便可以省略，不必拟合。过Q值便可以换算得到交流阻抗，从而根据交流阻抗在无线充电过程中进行Ploss异物检测。
异物检测方法实施例二：
本申请实施例拟合的偏差关系包括：发射线圈和接收线圈之间径向的水平关系以及所述发射线圈所在平面和所述接收线圈所在平面之间的竖直关系；
根据电子设备参数和无线充电设备参数拟合Q值相对于位置空间的偏差关系，具体包括：
根据电子设备参数中的Q1和f1拟合水平关系；
根据f0、Q0以及电子设备参数中的Q1值和f1拟合竖直关系。
另外，在一种可能的实现方式中，当发射线圈和接收线圈的位置偏差较小，可以忽略时，则拟合的偏差关系可以仅包括竖直关系。因为当无线充电设备中的发射线圈可以移动时，可以控制发射线圈移动与接收线圈对正。而竖直偏差在电子设备和无线充电设备的位 置固定不动时，则无法改变。
下面介绍几种拟合偏差关系的方法。
第一种：
电子设备参数包括所述发射线圈和所述接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12。
偏差关系包括：所述发射线圈和所述接收线圈之间径向的水平关系以及所述发射线圈所在平面和所述接收线圈所在平面之间的竖直关系。
根据无线充电设备参数和所述电子设备参数拟合Q值相对于位置空间的偏差关系，具体包括：
根据所述Q11、所述f11、所述Q12和所述f12拟合所述水平关系；
根据所述f0、所述Q0、所述Q11和所述f11拟合所述竖直关系；
或，根据所述f0、所述Q0、所述Q12和所述f12拟合所述竖直关系；
或，根据所述Q0、所述f0和所述水平关系中的至少一个点对应的Q和f拟合所述竖直关系；
获得水平关系和竖直关系以后，通过水平关系和竖直关系获得Q值阈值和交流阻抗。
第二种：
偏差关系包括：所述发射线圈和所述接收线圈之间径向的水平关系以及所述发射线圈所在平面和所述接收线圈所在平面之间的竖直关系。
电子设备参数还包括：所述至少一个位置无异物时的预存耦合参数；预存耦合参数包括以下至少一项：耦合系数和互感；
根据无线充电设备参数和所述电子设备参数拟合Q值相对于位置空间的偏差关系，具体包括：
根据所述f0、所述Q0以及所述至少一个相对位置的Q1值和f1拟合竖直关系；根据预存耦合参数和至少一个相对位置的Q1值拟合水平关系；
所述根据所述偏差关系获得Q值阈值和交流阻抗，具体包括：
获得水平关系和竖直关系以后，通过竖直关系和水平关系获得Q值阈值，根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的交流阻抗。
第三种：
电子设备参数包括所述发射线圈和所述接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12。偏差关系包括：所述发射线圈和所述接收线圈之间径向的水平关系以及所述发射线圈所在平面和所述接收线圈所在平面之间的竖直关系。
电子设备参数还包括：第一位置的预存耦合参数和第二位置的预存耦合参数；预存耦合参数包括以下至少一项：发射线圈和接收线圈之间的耦合系数和互感；
根据无线充电设备参数和所述电子设备参数拟合Q值相对于位置空间的偏差关系，具体包括：
根据所述Q11、所述Q12、所述第一位置的预存耦合参数和所述第二位置的预存耦合 参数拟合所述水平关系；
根据所述f0、所述Q0、所述Q11和所述f11拟合所述竖直关系；
或，根据所述f0、所述Q0、所述Q12和所述f12拟合所述竖直关系；
或，根据所述Q0、所述f0和所述水平关系中的至少一个点对应的Q和f拟合所述竖直关系；
根据所述偏差关系获得Q值阈值和交流阻抗，具体包括：
获得水平关系和竖直关系以后，通过所述竖直关系和所述水平关系获得Q值阈值，根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的交流阻抗。
由于第二种和第三种拟合的水平关系利用了预存耦合参数，因此后续使用偏差关系时可以利用在线检测的耦合参数通过该偏差关系获得对应的水平相对位置，即耦合参数与水平关系存在单调性，例如利用在线测试的耦合系数k通过偏差关系获得对应的水平相对位置，又由于水平相对位置与Q值存在单调关系，因此可以获得对应的Q值阈值。另外，也可以直接根据k与水平关系的单调性来获得Q值阈值，因此拟合的水平关系就是Q值相对于空间的水平单调关系。
第四种：
偏差关系包括：竖直关系；根据无线充电设备参数和所述电子设备参数拟合Q值相对于位置空间的偏差关系，具体包括：
根据所述f0、所述Q0以及电子设备参数中的Q1值和f1拟合所述竖直关系；通过所述竖直关系获得Q值阈值，根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的交流阻抗。
第四种仅适合发射线圈和接收线圈在水平方向上不存在偏差，或者偏差很小可以忽略不计的情况，仅拟合竖直偏差即可。当存在水平偏差时，无线充电设备的发射线圈如果可以对正，则可以对正后再判断异物。
对于电子设备参数仅包括一个位置时，可以准确拟合出Q值相对于竖直方向的关系，该方法尤其适用于无线充电设备具有自动对正功能的情况，即无线充电设备控制发射线圈移动，实现与接收线圈的对位，从而发射线圈与接收线圈之间的水平偏差较小或者忽略不计，仅考虑竖直偏差即可，因此，利用拟合的竖直关系进行Q值和Ploss异物检测，也可以保证异物检测结果的准确性。
在进行异物检测时，均可以利用以上四种拟合的竖直关系，即控制器，具体用于根据无线充电设备和电子设备在当前位置的谐振频率或发射线圈的自感通过竖直关系获得Q值阈值和交流阻抗。即利用f或L1通过拟合的竖直关系来获得用于异物检测Q值阈值和交流阻抗。由于f和L1之间可以换算，存在转换关系，因此，利用f也可以，利用L1也可以。下面结合流程图介绍以上各种拟合方式的具体实现步骤。
参见图19，该图为本申请实施例提供的另一种无线充电的异物检测方法的流程图。
图19对应的方法，电子设备参数包括：发射线圈和接收线圈至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12；电子设备参数还包括：耦合状态下接收线圈的自感L2；
因此，对应的异物检测方法包括：
S1701：接收电子设备发送的第一位置的Q11和f11、第二位置的Q12和f12；
S1702：根据f11、Q11、f12和Q12拟合水平关系；
S1703：根据所述f0、所述Q0、所述Q11和所述f11拟合所述竖直关系；或，根据所述f0、所述Q0、所述Q12和所述f12拟合所述竖直关系；或，根据所述Q0、所述f0和所述水平关系中的至少一个点对应的Q和f拟合所述竖直关系。
即拟合竖直关系时可以有S1703提供的三种方式，选择其中任意一种即可，但是，当选择最后一种，根据水平关系中的至少一个点对应的Q值和f时，需要先得到水平关系，再得到竖直关系。利用前两种方式拟合竖直关系时，则不需要先获得水平关系，即不限定获取水平关系和竖直关系的先后顺序。
由于Q值与交流阻抗存在转换关系，因此获得Q值相对于位置空间的水平关系和竖直关系，便可以获得交流阻抗相对于位置空间的水平关系和竖直关系。
S1704：根据水平关系和竖直关系获得Q值阈值，根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的交流阻抗。
S1705：在无线充电设备为电子设备充电之前根据Q值阈值进行Q值异物检测，在无线充电设备为电子设备充电过程中根据获得的交流阻抗进行Ploss异物检测。
本实施例提供的方法，电子设备可以不必获得耦合状态下的接收线圈的自感L2，仅获得非耦合状态下的接收线圈的自感L20即可，将L20发送给无线充电设备或无线充电底座，由无线充电设备根据L20获得L2。
以上介绍的方法是电子设备参数包括接收线圈的自感，当电子设备包括辅助线圈时，电子设备参数可以包括辅助线圈的自感，下面结合附图介绍借助辅助线圈的自感进行偏差关系拟合的过程。
参见图20，该图为本申请实施例提供的再一种无线充电的异物检测方法的流程图。
图20对应的方法，电子设备参数包括发射线圈和接收线圈之间至少两个相对位置的Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12。偏差关系包括：竖直关系和水平关系；电子设备参数还包括：所述第一位置的预存耦合参数和第二位置的预存耦合参数；预存耦合参数包括以下至少一项：耦合系数和互感；
S1901：接收电子设备发送的第一位置的Q11和f11、第二位置的Q12和f12；
S1902：根据Q11、Q12、第一位置的预存耦合参数和第二位置的预存耦合参数拟合所述水平关系；例如预存耦合参数为耦合系数k。
S1903：根据所述f0、所述Q0、所述Q11和所述f11拟合所述竖直关系；或，根据所述f0、所述Q0、所述Q12和所述f12拟合所述竖直关系；或，根据所述Q0、所述f0和所述水平关系中的至少一个点对应的Q和f拟合所述竖直关系。
需要说明的是，利用S1903中的前两种方式拟合竖直关系时，S1902和S1903没有先后顺序，可以同时进行，也可以先后进行，本申请实施例中不作具体限定。但是利用S1903的最后一种方式拟合竖直关系时，需要先拟合得到水平关系，再根据水平关系的结果来拟合竖直关系
S1904：根据水平关系和竖直关系获得Q值阈值，根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的交流阻抗。
S1905：在所述无线充电设备为所述电子设备充电之前根据所述Q值阈值进行Q值异物检测，在所述无线充电设备为所述电子设备充电过程中根据获得的所述交流阻抗进行Ploss异物检测。
以上介绍的是电子设备参数包括至少两个相对位置的Q1和f1，下面介绍电子设备参数包括至少一个位置时的情况。此时电子设备参数还可以包括：至少一个相对位置无异物时的耦合参数；耦合参数包括以下至少一项：发射线圈和接收线圈之间的耦合系数和互感；
参见图21，该图为本申请实施例提供的又一种无线充电的异物检测方法的流程图。
S2001：接收电子设备发送的第一位置的Q11和f11、第二位置的Q12和f12，以及至少一个位置无异物时的预存耦合系数。
S2002：根据f0、Q0以及至少一个位置的Q1值和f1拟合竖直关系；
S2003：根据至少一个位置的预存耦合参数和Q值拟合水平关系；
即电子设备参数中包括的耦合参数参与水平关系的拟合，由于耦合参数与水平相对位置之间存在单调关系。
S2004：根据水平关系和竖直关系获得Q值阈值，根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的交流阻抗。
S2005：在所述无线充电设备为所述电子设备充电之前根据所述Q值阈值进行Q值异物检测，在所述无线充电设备为所述电子设备充电过程中根据获得的所述交流阻抗进行Ploss异物检测。
本实施例提供的方法，电子设备参数可以仅包括一个位置的参数，但是由于电子设备参数包括预存耦合参数，因此，利用一个位置的参数也可以准确拟合水平关系，因为预存耦合参数与水平相位位置存在单调关系，本实施例利用该单调关系可以准确拟合水平关系。
异物检测方法实施例三：
当偏差关系仅包括竖直关系时，控制器可以根据无线充电设备和电子设备在当前位置的谐振频率或发射线圈的自感通过竖直关系获得Q值阈值和交流阻抗，利用Q值阈值进行Q值异物检测，利用交流阻抗进行Ploss异物检测。以上各种拟合偏差关系的方式适用于各种类型的无线充电设备，例如具有自动对位功能的无线充电设备，也适用于具有机械卡位功能的无线充电设备，也适用于具有磁吸对位功能的无线充电设备。
下面介绍发射线圈和接收线圈没有对正时异物检测的方法。
参见图22，该图为本申请实施例提供的一种异物检测方法的流程图。
S2201：接收电子设备发送的电子设备参数；
其中电子设备参数可以为以上方法实施例二中介绍的各种情况，在此不再赘述。
S2202：根据电子设备参数和无线充电设备参数拟合得到偏差关系；
电子设备参数也可以参照方法实施例二介绍的情况。偏差关系的具体拟合方式也可以参照方法实施例二的介绍，在此不再赘述。
S2203：获得无线充电设备和电子设备之间的当前相对位置对应的耦合状态下的耦合参 数和发射线圈的自感L1；
耦合参数可以包括耦合系数k或互感M。耦合参数与水平关系存在单调关系，L1与竖直关系存在单调关系。
下面介绍耦合参数的获取方式，该耦合参数是无线充电设备在线测试获得的，而不是从电子设备接收的电子设备参数中的，即不是电子设备预存的耦合参数。
第一种：
耦合参数为所述发射线圈与所述接收线圈之间的，控制器，还用于接收所述电子设备发送的耦合状态下接收线圈的自感L2；根据所述发射线圈的电流、耦合状态下发射线圈的自感L1、所述L2和所述接收线圈对应的整流电压获得耦合参数。
第二种：
耦合参数为所述发射线圈与接收线圈之间的，控制器，还用于接收所述电子设备发送的非耦合状态下接收线圈的自感L20；根据耦合状态下发射线圈的自感L1、非耦合状态下发射线圈的自感L10、所述L20获得耦合状态下接收线圈的自感L2，根据所述L1、所述L2和所述接收线圈对应的整流电压获得耦合参数。
第三种：
耦合参数为发射线圈与辅助线圈之间的，控制器，还用于接收所述电子设备发送的耦合状态下辅助线圈的自感L3；根据所述发射线圈的电流、耦合状态下发射线圈的自感L1、所述L3和所述辅助线圈对应的整流电压获得耦合参数。
第四种：
耦合参数为发射线圈与辅助线圈之间的，控制器，还用于接收所述电子设备发送的非耦合状态下辅助线圈的自感L30；根据耦合状态下发射线圈的自感L1、非耦合状态下发射线圈的自感L10、所述L30获得耦合状态下辅助线圈的自感L3，根据所述L1、所述L3和所述辅助线圈对应的整流电压获得耦合参数。
以上四种获得耦合参数的方式，其中第一种和第二种均为发射线圈和接收线圈之间的，具体地，电子设备参数还包括耦合状态下接收线圈的自感或非耦合状态下接收线圈的自感。第三种和第四种均为发射线圈和辅助线圈之间，具体地，电子设备参数还包括耦合状态下辅助线圈的自感或非耦合状态下辅助线圈的自感。
其中获得耦合参数时利用的发射线圈的电流的获取，可以参见以上图11和图12介绍的方式，在此不再赘述。
S2204：根据耦合参数和L1通过偏差关系获得当前相对位置对应的Q值阈值和交流阻抗；
例如，根据耦合系数获得当前水平相对位置，根据L1获得当前竖直相对位置，根据当前水平相对位置和当前竖直相对位置通过偏差关系，可以获得对应的Q值阈值和交流阻抗。因为偏差关系可以为一次函数或多次函数，即偏差关系为位置偏差与Q值的函数表达式，因此，当位置偏差已知时，根据已知的函数表达式，可以获得对应的Q值。
S2205：根据Q值阈值进行Q值异物检测，根据交流阻抗和以上获得的耦合状态下的耦合参数进行Ploss异物检测。
无线充电设备进行Ploss异物检测时利用交流阻抗和耦合参数的具体实现方式可以参考无线充电设备实施例中的介绍，在此不再赘述。
本申请实施例提供的异物检测方法可以适用于不具有自动对位功能的无线充电设备，由于无线充电设备拟合得到整个位置空间的偏差关系，因为即使发射线圈和接收线圈存在空间位置的偏差，也可以获得偏差下对应的Q值阈值和交流阻抗，进而进行异物检测，也可以保证异物检测结果的准确性。
异物检测方法实施例四：
参见图23，该图为本申请实施例提供的带有对位的异物检测方法的流程图。
本实施例介绍无线充电设备具有自动对位功能时的异物检测过程。
S2301：接收电子设备发送的电子设备参数；
其中电子设备参数可以为以上方法实施例二中介绍的各种情况，在此不再赘述。
S2302：根据电子设备参数和无线充电设备参数拟合得到偏差关系；
电子设备参数也可以参照方法实施例二介绍的情况。偏差关系的具体拟合方式也可以参照方法实施例二的介绍，在此不再赘述。
S2303：获得耦合状态下的发射线圈的自感和耦合参数，耦合参数包括：耦合系数和互感。
一种实现方式为：耦合参数为所述发射线圈与所述接收线圈之间的，根据所述发射线圈的电流、所述发射线圈的自感、所述接收线圈的自感和所述接收线圈对应的整流电压获得所述耦合参数。
另一种实现方式为：耦合参数为所述发射线圈与所述辅助线圈之间的，根据所述发射线圈的电流、所述发射线圈的自感、所述辅助线圈的自感和所述辅助线圈对应的整流电压获得所述耦合参数。
S2304：根据发射线圈的自感和耦合参数确定发射线圈和接收线圈之间的水平相对位置和竖直相对位置；
S2305：根据所述水平相对位置移动所述发射线圈，使所述发射线圈与所述接收线圈对正；
所述根据所述水平相对位置移动所述发射线圈，使所述发射线圈与所述接收线圈对正，具体包括：
获得所述两个不同位置对应的两个水平相对位置分别为半径的第一圆周和第二圆周；
获得所述第一圆周和所述第二圆周的交叉点，控制所述发射线圈对正至所述交叉点。
还包括：
移动所述发射线圈到第三位置，所述第三位置区别于所述两个不同位置；
获得移动过程中的以下至少一项参数，根据所述至少一项参数的变化趋势确定所述发射线圈对正至的所述交叉点；所述至少一项参数包括：所述耦合参数、充电效率、所述发射线圈的自感、所述发射线圈的电流和所述接收端的输出电压。
所述发射线圈的自感与所述竖直相对位置存在第一单调关系，所述至少一项耦合参数与所述水平相对位置存在第二单调关系。
S2306：根据所述发射线圈的自感通过所述偏差关系获得Q值阈值，根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的交流阻抗；
S2307：在无线充电设备为电子设备充电之前根据对正后的Q值阈值进行Q值异物检测；在无线充电设备为电子设备充电过程中根据对正后的交流阻抗进行Ploss异物检测。
本申请实施例提供的异物检测方法，可以实现整个空间的偏差关系拟合，实现对于Q值的线性化，同时实现对于不同电子设备的归一化。而且无线充电设备具有自动对位的功能，由于自动对位之后，还可能存在稍微偏差，因此，可以根据对位后的相对位置通过偏差关系，获得对正后对应的Q值阈值和交流阻抗，进而进行对正后的Q值异物检测和Ploss异物检测，进而更一步保证异物检测结果的准确性。
另外，当发射线圈对位后，发射线圈和接收线圈之间的水平偏差很小可以忽略不计时，可以不必考虑水平偏差的影响，仅考虑竖直偏差的影响即可，即在另一种实现方式中，获得对正后的耦合参数，根据耦合参数判断对正后的水平相对位置在预设偏差范围内时，根据对正后的所述发射线圈的自感获得对正后的竖直相对位置。即在发射线圈与所述接收线圈对正后，还包括：根据所述发射线圈的自感通过所述偏差关系获得所述Q值阈值和所述交流阻抗；根据所述Q值阈值进行Q值异物检测，根据所述交流阻抗和所述耦合参数进行Ploss异物检测。
基于以上实施例提供的一种无线充电设备、无线充电底座及无线充电的异物检测方法，本申请实施例还提供一种无线充电系统，下面结合附图进行详细介绍。
无线充电系统实施例一：
参见图24，该图为本申请实施例提供的一种无线充电系统的示意图。
本申请实施例提供的无线充电系统，包括以上实施例介绍的无线充电设备30，还包括电子设备20；
电子设备20包括：接收线圈和整流电路。电子设备的结构可以参见图3所示。
无线充电设备30，用于给电子设备20进行无线充电。
无线充电设备30可以为无线充电底座。电子设备20可以为手机或可穿戴设备，可穿戴设备例如可以为手表等。
本申请实施例提供的无线充电系统，其中的无线充电设备预存无线充电设备参数，电子设备预存电子设备参数，电子设备将预存的电子设备参数发送给无线充电设备，无线充电设备根据无线充电设备参数和电子设备参数拟合整个空间的Q值的偏差关系，实现Q值相对于整个空间的线性化和不同电子设备的归一化，从而可以根据实际的相对位置通过偏差关系获得Q值阈值和交流阻抗，根据Q值阈值进行Q值异物检测，根据交流阻抗进行Ploss异物检测，该无线充电设备不需存储Q值与整个位置空间的对应关系，同理也不需存储发射线圈的交流阻抗与整个位置空间的对应关系。无线充电设备仅根据有限数量的参数便可以拟合出Q值相对于整个位置空间的对应关系，从而可以降低对于硬件性能和存储空间的要求。
应当理解，在本申请中，“至少一个(项)”是指一个或者多个，“多个”是指两个或两个以上。“和/或”，用于描述关联对象的关联关系，表示可以存在三种关系，例如，“A 和/或B”可以表示：只存在A，只存在B以及同时存在A和B三种情况，其中A，B可以是单数或者复数。字符“/”一般表示前后关联对象是一种“或”的关系。“以下至少一项(个)”或其类似表达，是指这些项中的任意组合，包括单项(个)或复数项(个)的任意组合。例如，a，b或c中的至少一项(个)，可以表示：a，b，c，“a和b”，“a和c”，“b和c”，或“a和b和c”，其中a，b，c可以是单个，也可以是多个。
以上所述，仅是本申请的较佳实施例而已，并非对本申请作任何形式上的限制。虽然本申请已以较佳实施例揭露如上，然而并非用以限定本申请。任何熟悉本领域的技术人员，在不脱离本申请技术方案范围情况下，都可利用上述揭示的方法和技术内容对本申请技术方案做出许多可能的变动和修饰，或修改为等同变化的等效实施例。因此，凡是未脱离本申请技术方案的内容，依据本申请的技术实质对以上实施例所做的任何简单修改、等同变化及修饰，均仍属于本申请技术方案保护的范围内。

Claims (34)

  1. 一种无线充电设备，其特征在于，所述无线充电设备用于为电子设备进行无线充电，所述无线充电设备包括：谐振网络、逆变电路和控制器；
    所述谐振网络包括谐振电容和发射线圈；
    所述逆变电路的输入端用于连接直流电源，所述逆变电路的输出端用于连接所述谐振网络；
    所述控制器，用于接收所述电子设备发送的电子设备参数，根据无线充电设备参数和所述电子设备参数拟合所述无线充电设备的Q值相对于位置空间的偏差关系，所述位置空间为所述发射线圈和所述电子设备的接收线圈之间的位置空间；其中所述电子设备参数包括：所述发射线圈和所述接收线圈之间至少一个相对位置无异物时的所述无线充电设备的Q1值和所述谐振网络的谐振频率f1；所述无线充电设备参数包括：所述无线充电设备与所述电子设备非耦合状态下所述无线充电设备的的初始Q值Q0和所述谐振网络的初始谐振频率f0；
    所述控制器，还用于根据所述偏差关系进行异物检测。
  2. 根据权利要求1所述的无线充电设备，其特征在于，所述控制器，具体用于根据所述偏差关系获得Q值阈值，并在所述无线充电设备为所述电子设备充电之前根据所述Q值阈值进行Q值异物检测。
  3. 根据权利要求1或2所述的无线充电设备，其特征在于，所述控制器，具体用于根据所述偏差关系获得Q值阈值，根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的交流阻抗；在所述无线充电设备为所述电子设备充电过程中根据获得的所述交流阻抗进行Ploss异物检测。
  4. 根据权利要求2或3所述的无线充电设备，其特征在于，所述偏差关系包括：所述发射线圈所在平面和所述接收线圈所在平面之间的竖直关系；
    所述控制器，具体用于根据所述f0、所述Q0以及所述Q1值和所述f1拟合Q值相对于位置空间的所述竖直关系；通过所述竖直关系获得所述Q值阈值，并根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的所述交流阻抗。
  5. 根据权利要求3所述的无线充电设备，其特征在于，所述电子设备参数包括所述发射线圈和所述接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12；所述偏差关系包括：所述发射线圈和所述接收线圈之间径向的水平关系以及所述发射线圈所在平面和所述接收线圈所在平面之间的竖直关系；
    所述控制器，具体用于根据所述Q11、所述f11、所述Q12和所述f12拟合Q值相对于位置空间的所述水平关系；通过以下任一方式拟合Q值相对于位置空间的所述竖直关系：根据所述f0、所述Q0、所述Q11和所述f11；或，根据所述f0、所述Q0、所述Q12和所述f12拟合Q值相对于位置空间的所述竖直关系；或，根据所述Q0、所述f0和所述水平关系中的至少一个点对应的Q和f拟合Q值相对于位置空间的所述竖直关系；
    通过所述水平关系和所述竖直关系获得所述Q值阈值，并根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的所述交流阻抗。
  6. 根据权利要求3所述的无线充电设备，其特征在于，所述偏差关系包括：所述发射线圈和所述接收线圈之间径向的水平关系以及所述发射线圈所在平面和所述接收线圈所在平面之间的竖直关系；
    所述电子设备参数还包括：所述发射线圈和所述接收线圈之间至少一个相对位置无异物时的预存耦合参数；所述预存耦合参数包括以下至少一项：所述发射线圈和所述接收线圈之间的耦合系数和互感；
    所述控制器，具体用于根据所述f0、所述Q0以及所述发射线圈和所述接收线圈之间至少一个相对位置的所述Q值和所述f拟合Q值相对于位置空间的所述竖直关系；根据所述预存耦合参数和所述发射线圈和所述接收线圈之间至少一个相对位置的所述Q值拟合Q值相对于位置空间的所述水平关系；通过所述竖直关系和所述水平关系获得所述Q值阈值，并根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的所述交流阻抗。
  7. 根据权利要求3所述的无线充电设备，其特征在于，所述电子设备参数包括所述发射线圈和所述接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12；
    所述偏差关系包括：所述发射线圈和所述接收线圈之间径向的水平关系以及所述发射线圈所在平面和所述接收线圈所在平面之间的竖直关系；
    所述电子设备参数还包括：所述第一位置的预存耦合参数和第二位置的预存耦合参数；所述预存耦合参数包括以下至少一项：所述发射线圈和所述接收线圈之间的耦合系数和互感；
    所述控制器，具体用于根据所述Q11、所述Q12、所述第一位置的预存耦合参数和所述第二位置的预存耦合参数拟合Q值相对于位置空间的所述水平关系；
    通过以下任一方式拟合Q值相对于位置空间的所述竖直关系：根据所述f0、所述Q0、所述Q11和所述f11；或，根据所述f0、所述Q0、所述Q12和所述f12拟合Q值相对于位置空间的所述竖直关系；或，根据所述Q0、所述f0和所述水平关系中的至少一个点对应的Q和f拟合Q值相对于位置空间的所述竖直关系；
    通过所述竖直关系和所述水平关系获得所述Q值阈值，并根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的所述交流阻抗。
  8. 根据权利要求3-7任一项所述的无线充电设备，其特征在于，所述控制器，具体用于根据所述无线充电设备和所述电子设备在当前相对位置的所述谐振网络的谐振频率或所述发射线圈的自感通过所述竖直关系获得所述Q值阈值，并根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的所述交流阻抗。
  9. 根据权利要求6或7所述的无线充电设备，其特征在于，所述控制器，还用于获得所述无线充电设备和所述电子设备在耦合状态下的耦合参数和所述发射线圈的自感L1；所述耦合状态下的耦合参数包括以下至少一项：所述发射线圈和所述接收线圈之 间的耦合系数和互感；
    根据所述耦合状态下的耦合参数和所述L1通过所述偏差关系获得所述Q值阈值，并根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的所述交流阻抗；所述耦合状态下的耦合参数与所述水平关系存在单调关系，所述L1与所述竖直关系存在单调关系。
  10. 根据权利要求9所述的无线充电设备，其特征在于，所述控制器，具体用于接收所述电子设备发送的所述无线充电设备和所述电子设备在耦合状态下接收线圈的自感L2；根据所述发射线圈的电流、耦合状态下发射线圈的自感L1、所述L2和所述接收线圈对应的整流电压获得所述耦合状态下的耦合参数。
  11. 根据权利要求9所述的无线充电设备，其特征在于，所述控制器，具体用于接收所述电子设备发送的所述无线充电设备和所述电子设备在非耦合状态下接收线圈的自感L20；根据耦合状态下发射线圈的自感L1、非耦合状态下发射线圈的自感L10、所述L20获得耦合状态下所述接收线圈的自感L2，根据所述L1、所述L2和所述接收线圈对应的整流电压获得所述耦合状态下的耦合参数。
  12. 根据权利要求9所述的无线充电设备，其特征在于，所述控制器，还用于接收所述电子设备发送的所述无线充电设备和所述电子设备在耦合状态下辅助线圈的自感L3；根据所述发射线圈的电流、耦合状态下发射线圈的自感L1、所述L3和所述辅助线圈对应的整流电压获得所述耦合状态下的耦合参数。
  13. 根据权利要求9所述的无线充电设备，其特征在于，所述控制器，还用于接收所述电子设备发送的所述无线充电设备和所述电子设备在非耦合状态下辅助线圈的自感L30；根据耦合状态下发射线圈的自感L1、非耦合状态下发射线圈的自感L10、所述L30获得耦合状态下辅助线圈的自感L3，根据所述L1、所述L3和所述辅助线圈对应的整流电压获得所述耦合状态下的耦合参数。
  14. 根据权利要求1-13任一项所述的无线充电设备，其特征在于，所述控制器，还用于获得所述无线充电设备和所述电子设备在耦合状态下的耦合参数，具体用于根据所述交流阻抗和所述耦合状态下的耦合参数进行Ploss异物检测。
  15. 根据权利要求8-13任一项所述的无线充电设备，其特征在于，还包括：发射线圈的电流检测电路；
    所述电流检测电路，用于检测所述谐振电容两端的电压差；
    所述控制器，用于根据所述电压差获得所述发射线圈的电流。
  16. 根据权利要求15所述的无线充电设备，其特征在于，所述电流检测电路包括：第一电压检测电路、第二电压检测电路和差分电路；
    所述第一电压检测电路，用于检测所述谐振电容的第一端的第一电压，将所述第一电压分压后发送给所述差分电路的第一输入端；
    所述第二电压检测电路，用于检测所述谐振电容的第二端的第二电压，将所述第二电压分压后发送给所述差分电路的第二输入端；
    所述差分电路，用于获得所述第一输入端输入的电压和所述第二输入端输入的电 压的差分结果；
    所述控制器，用于根据所述差分结果获得所述发射线圈的电流。
  17. 根据权利要求9-15任一项所述的无线充电设备，其特征在于，所述控制器，还用于根据所述发射线圈的自感和所述耦合参数确定所述发射线圈和接收线圈之间的水平相对位置和竖直相对位置，根据所述水平相对位置移动所述发射线圈，使所述发射线圈与所述接收线圈对正；
    所述发射线圈的自感与所述竖直相对位置存在单调关系，所述耦合参数与所述水平相对位置存在单调关系。
  18. 根据权利要求17所述的无线充电设备，其特征在于，所述控制器，具体用于获得所述无线充电设备和所述电子设备在两个不同相对位置对应的两个水平相对位置，获得分别以所述两个水平相对位置为半径的第一圆周和第二圆周，获得所述第一圆周和所述第二圆周的交叉点，控制所述发射线圈对正至所述交叉点。
  19. 根据权利要求18所述的无线充电设备，其特征在于，所述控制器，还用于移动所述发射线圈到第三位置，所述第三位置区别于所述两个不同相对位置；获得移动过程中的以下至少一项参数，根据所述至少一项参数的变化趋势确定所述发射线圈对正至的所述交叉点；
    所述至少一项参数包括：所述耦合参数、充电效率、所述发射线圈的自感、所述发射线圈的电流和所述接收端的输出电压。
  20. 根据权利要求18所述的无线充电设备，其特征在于，所述控制器，具体用于控制所述发射线圈移动到第四位置，所述第四位置与所述两个不同相对位置不在同一直线，获得所述第四位置对应的发射线圈的自感与耦合参数；根据所述第四位置对应的发射线圈的自感和耦合参数确定所述水平相对位置和所述竖直相对位置，依据所述水平相对位置确定第三圆周，控制所述发射线圈移动至所述第三圆周与所述交叉点的公共点。
  21. 根据权利要求17-20任一项所述的无线充电设备，其特征在于，还包括：对位机构；
    所述控制器，用于控制所述对位机构驱动所述发射线圈，以使所述发射线圈与所述接收线圈对正。
  22. 根据权利要求17-20任一项所述的无线充电设备，其特征在于，所述控制器，在所述发射线圈与所述接收线圈对正后，还用于根据所述发射线圈的自感通过所述偏差关系获得所述Q值阈值，并通过Q值与所述发射线圈的交流阻抗之间的比例关系根据所述Q值阈值获得对应的所述交流阻抗；在所述无线充电设备为所述电子设备充电之前根据所述Q值阈值进行Q值异物检测，或在所述无线充电设备为所述电子设备充电过程中根据所述交流阻抗和所述耦合状态下的耦合参数进行Ploss异物检测。
  23. 根据权利要求14或22所述的无线充电设备，其特征在于，根据所述交流阻抗和所述耦合状态下的耦合参数进行Ploss异物检测，具体通过以下公式获得所述无线充电的功率损耗；
    P tx loss＝f(Vin)+f(TxACR,k,I1)
    f(TxACR,k,I1)＝(a+TxACR*f(k))*I1 2+b*I1+c；
    其中，Vin为所述逆变电路的母线电压；TxACR为所述发射线圈的交流阻抗ACR；k为所述耦合参数中的耦合系数；I1为所述发射线圈的电流；a、b、c、d为所述无线充电设备的已知参数。
  24. 一种无线充电底座，其特征在于，包括：用于为电子设备进行无线充电，包括：电源接口、谐振网络、逆变电路、控制器和发射线圈底盘；
    所述电源接口，用于连接适配器传输的直流电；
    所述谐振网络包括谐振电容和发射线圈；
    所述发射线圈底盘，用于放置所述发射线圈；
    所述逆变电路的输入端用于连接所述电源接口，所述逆变电路的输出端用于连接所述谐振网络；
    所述控制器，用于接收所述电子设备发送的电子设备参数，根据无线充电设备参数和所述电子设备参数拟合所述无线充电设备的Q值相对于位置空间的偏差关系，所述位置空间为所述发射线圈和所述电子设备的接收线圈之间的位置空间；其中所述电子设备参数包括：所述发射线圈和所述接收线圈之间至少一个相对位置无异物时的所述无线充电设备的Q1值和所述谐振网络的谐振频率f1；所述无线充电设备参数包括：所述无线充电设备与所述电子设备非耦合状态下所述无线充电设备的的初始Q值Q0和所述谐振网络的初始谐振频率f0；
    所述控制器，还用于根据所述偏差关系进行异物检测。
  25. 根据权利要求24所述的无线充电设备，其特征在于，所述控制器，具体用于根据所述偏差关系获得Q值阈值，并在所述无线充电设备为所述电子设备充电之前根据所述Q值阈值进行Q值异物检测。
  26. 根据权利要求24或25所述的无线充电设备，其特征在于，所述控制器，具体用于根据所述偏差关系获得Q值阈值，根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的交流阻抗；在所述无线充电设备为所述电子设备充电过程中根据获得的所述交流阻抗进行Ploss异物检测。
  27. 根据权利要求26所述的无线充电底座，其特征在于，所述电子设备参数包括所述发射线圈和所述接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12；所述偏差关系包括：所述发射线圈和所述接收线圈之间径向的水平关系以及所述发射线圈所在平面和所述接收线圈所在平面之间的竖直关系；
    所述控制器，具体用于根据所述Q11、所述f11、所述Q12和所述f12拟合Q值相对于位置空间的所述水平关系；
    通过以下任一方式拟合Q值相对于位置空间的所述竖直关系：根据所述f0、所述Q0、所述Q11和所述f11；或，根据所述f0、所述Q0、所述Q12和所述f12拟合Q值相对于位置空间的所述竖直关系；或，根据所述Q0、所述f0和所述水平关系中的至少一个点对应的Q和f拟合Q值相对于位置空间的所述竖直关系；
    通过所述水平关系和所述竖直关系获得所述Q值阈值，并根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的所述交流阻抗。
  28. 根据权利要求26所述的无线充电底座，其特征在于，所述电子设备参数包括所述发射线圈和所述接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12；所述偏差关系包括：所述发射线圈和所述接收线圈之间径向的水平关系以及所述发射线圈所在平面和所述接收线圈所在平面之间的竖直关系；所述电子设备参数还包括：所述第一位置的预存耦合参数和第二位置的预存耦合参数；所述预存耦合参数包括以下至少一项：所述发射线圈和所述接收线圈之间的耦合系数和互感；
    所述控制器，具体用于根据所述Q11、所述Q12、所述第一位置的预存耦合参数和所述第二位置的预存耦合参数拟合Q值相对于位置空间的所述水平关系；通过以下任一方式拟合Q值相对于位置空间的所述竖直关系：根据所述f0、所述Q0、所述Q11和所述f11；或，根据所述f0、所述Q0、所述Q12和所述f12拟合Q值相对于位置空间的所述竖直关系；或，根据所述Q0、所述f0和所述水平关系中的至少一个点对应的Q和f拟合Q值相对于位置空间的所述竖直关系；
    通过所述竖直关系和所述水平关系获得所述Q值阈值，并根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的所述交流阻抗。
  29. 一种无线充电的异物检测方法，其特征在于，应用于无线充电设备，所述无线充电设备包括：谐振网络和逆变电路；所述谐振网络包括谐振电容和发射线圈；所述逆变电路的输入端用于连接直流电源，所述逆变电路的输出端用于连接所述谐振网络；
    该方法包括：
    接收所述电子设备发送的电子设备参数；
    根据无线充电设备参数和所述电子设备参数拟合所述无线充电设备的Q值相对于位置空间的偏差关系，所述位置空间为所述发射线圈和所述电子设备的接收线圈之间的位置空间；其中所述电子设备参数包括：所述发射线圈和所述接收线圈之间至少一个相对位置无异物时的所述无线充电设备的Q1值和所述谐振网络的谐振频率f1；所述无线充电设备参数包括：所述无线充电设备与所述电子设备非耦合状态下所述无线充电设备的初始Q值Q0和所述谐振网络的初始谐振频率f0；
    根据所述偏差关系进行异物检测。
  30. 根据权利要求29所述的方法，其特征在于，根据所述偏差关系进行异物检测，具体包括：
    根据所述偏差关系获得Q值阈值，并在所述无线充电设备为所述电子设备充电之前根据所述Q值阈值进行Q值异物检测。
  31. 根据权利要求29或30所述的方法，其特征在于，根据所述偏差关系进行异物检测，具体包括：
    根据所述偏差关系获得Q值阈值；
    根据所述Q值阈值以及Q值与所述发射线圈的交流阻抗的对应关系获得对应的交 流阻抗；
    在所述无线充电设备为所述电子设备充电过程中根据获得的所述交流阻抗进行Ploss异物检测。
  32. 根据权利要求31所述的方法，其特征在于，所述电子设备参数包括所述发射线圈和所述接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12；所述偏差关系包括：所述发射线圈和所述接收线圈之间径向的水平关系以及所述发射线圈所在平面和所述接收线圈所在平面之间的竖直关系；
    所述根据无线充电设备参数和所述电子设备参数拟合所述无线充电设备的Q值相对于位置空间的偏差关系，具体包括：
    根据所述Q11、所述f11、所述Q12和所述f12拟合Q值相对于位置空间的所述水平关系；通过以下任一方式拟合Q值相对于位置空间的所述竖直关系：根据所述f0、所述Q0、所述Q11和所述f11；或，根据所述f0、所述Q0、所述Q12和所述f12拟合Q值相对于位置空间的所述竖直关系；或，根据所述Q0、所述f0和所述水平关系中的至少一个点对应的Q和f拟合Q值相对于位置空间的所述竖直关系；
    所述根据所述偏差关系获得Q值阈值，具体包括：
    通过所述水平关系和所述竖直关系获得所述Q值阈值。
  33. 根据权利要求31所述的方法，其特征在于，所述偏差关系包括：所述发射线圈和所述接收线圈之间径向的水平关系以及所述发射线圈所在平面和所述接收线圈所在平面之间的竖直关系；所述电子设备参数还包括：所述发射线圈和所述接收线圈之间至少一个相对位置无异物时的预存耦合参数；所述预存耦合参数包括以下至少一项：所述发射线圈和所述接收线圈之间的耦合系数和互感；
    所述根据无线充电设备参数和所述电子设备参数拟合所述无线充电设备的Q值相对于位置空间的偏差关系，具体包括：
    根据所述f0、所述Q0以及所述发射线圈和所述接收线圈之间至少一个相对位置的所述Q值和所述f拟合Q值相对于位置空间的所述竖直关系；根据所述预存耦合参数和所述发射线圈和所述接收线圈之间至少一个相对位置的所述Q值拟合Q值相对于位置空间的所述水平关系；
    所述根据所述偏差关系获得Q值阈值，具体包括：
    通过所述竖直关系和所述水平关系获得所述Q值阈值。
  34. 根据权利要求31所述的方法，其特征在于，所述电子设备参数包括所述发射线圈和所述接收线圈之间至少两个相对位置的以下Q1值和f1：第一位置的Q11和f11，第二位置的Q12和f12；所述偏差关系包括：所述发射线圈和所述接收线圈之间径向的水平关系以及所述发射线圈所在平面和所述接收线圈所在平面之间的竖直关系；所述电子设备参数还包括：所述第一位置的预存耦合参数和第二位置的预存耦合参数；所述预存耦合参数包括以下至少一项：所述发射线圈和所述接收线圈之间的耦合系数和互感；
    所述根据无线充电设备参数和所述电子设备参数拟合所述无线充电设备的Q值相 对于位置空间的偏差关系，具体包括：
    根据所述Q11、所述Q12、所述第一位置的预存耦合参数和所述第二位置的预存耦合参数拟合Q值相对于位置空间的所述水平关系；通过以下任一方式拟合Q值相对于位置空间的所述竖直关系：根据所述f0、所述Q0、所述Q11和所述f11；或，根据所述f0、所述Q0、所述Q12和所述f12拟合Q值相对于位置空间的所述竖直关系；或，根据所述Q0、所述f0和所述水平关系中的至少一个点对应的Q和f拟合Q值相对于位置空间的所述竖直关系；
    所述根据所述偏差关系获得Q值阈值，具体包括：
    通过所述竖直关系和所述水平关系获得所述Q值阈值。
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