JP2017143689A - Control device, power transmission device, and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device, a power transmission device, an electronic apparatus, and the like that can shorten time until reception power at a power reception device comes close to a target value.SOLUTION: A control device 20 is used for a power transmission device 10 that transmits power to a power reception device 40 by noncontact power transmission. The control device includes: a control unit 24 for controlling a power transmission unit 12 that transmits power to the power reception device 40; and a communication unit 30 that performs communication processing to receive communication data transmitted by the power reception device 40. The control unit 24 obtains information on a transmission power setting value for setting the magnitude of power transmitted from the power transmission device to the power reception device on the basis of the communication data, and controls the transmission power of the power transmission unit 12 by larger power width as difference between the transmission power setting value and the target value is larger.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a control device, a power transmission device, an electronic device, and the like.

  In recent years, contactless power transmission (non-contact power transmission) that uses electromagnetic induction and enables power transmission even without a contact of a metal part has been in the spotlight. As an application example of this contactless power transmission, charging of electronic devices such as household devices, portable terminals, and electric vehicles has been proposed.

  As a conventional technique for contactless power transmission, for example, there is a technique disclosed in Patent Document 1. Patent Document 1 discloses an invention in which a power transmitting device controls a transmitted power value based on a received power value received by a power receiving device.

Japanese Patent Laying-Open No. 2015-089187

  There is a time lag between the change in transmitted power in the power transmission device and the change in received power in the power reception device. Therefore, before the influence due to the change in the transmitted power appears in the received power, the power receiving device may transmit the information on the received power before the change to the power transmitting device. In this case, the power transmission device determines that the received power has not yet approached the target value based on the notified received power before the change, further changes the transmitted power, and as a result, the received power becomes the target value. May pass by. For this reason, the received power may swing above and below the target value and may take time to converge to the target value, or may not converge to the target value indefinitely.

  In addition, since the relationship between the variation amount of the transmitted power and the variation amount of the received power varies depending on the transmission capability of electromagnetic induction and the positional relationship between the power transmission device and the power reception device, stable control is difficult.

  According to some aspects of the present invention, it is possible to provide a control device, a power transmission device, an electronic device, and the like that can shorten the time until the received power in the power receiving device approaches the target value.

  One aspect of the present invention is a control device used in a power transmission device that transmits power to a power reception device by contactless power transmission, the control unit controlling a power transmission unit that transmits power to the power reception device, and the power reception A communication unit that performs communication processing for receiving communication data transmitted by the device, and the control unit sets a magnitude of power to be transmitted from the power transmission device to the power reception device based on the communication data The transmission power set value information is acquired, and the control device controls the transmitted power of the power transmission unit with a larger power width as the difference between the transmitted power set value and the target value increases.

  In one aspect of the present invention, the transmission power of the power transmission unit is controlled with a larger power width as the difference between the transmission power setting value and the target value is larger. The greater the transmitted power, the greater the received power in the power receiving device. Therefore, it is possible to shorten the time until the received power in the power receiving apparatus approaches the target value.

  In one aspect of the present invention, the control unit acquires information on an output voltage of the power receiving unit of the power receiving device as information on the transmission power setting value based on the communication data, and the target that is the target value The transmission power of the power transmission unit may be controlled with a larger power width as the difference between the voltage and the output voltage of the power reception unit increases.

  Thereby, it is possible to shorten the time until the output voltage of the power receiving unit approaches the target voltage.

  In the aspect of the invention, the power transmission unit may include a power transmission driver, and the control unit may control the transmitted power by changing a drive voltage supplied as a power source to the power transmission driver.

  As a result, it is possible to control the drive voltage of the power transmission unit to bring the output voltage of the power reception unit close to the target voltage.

  Moreover, in one aspect of the present invention, the control unit, when a difference value between the transmission power setting value and the target value is larger than a first predetermined value, the transmission power with a first power width. And when the difference value between the transmission power set value and the target value is less than the first predetermined value and larger than the second predetermined value, the second smaller than the first power width. The transmitted power may be controlled with a power width of.

  Thereby, it becomes possible to shorten the time taken until the difference value between the transmission power set value and the target value becomes equal to or less than the first predetermined value.

  Moreover, in one aspect of the present invention, the control unit, when the difference value between the transmission power set value and the target value is less than the first predetermined value and larger than the second predetermined value. In the first period, when the transmission power for the second power width is changed, and the difference value between the transmission power setting value and the target value is less than or equal to the second predetermined value, In the second period longer than the first period, the transmitted power for the second power width may be changed.

  Thereby, when the difference value between the transmission power set value and the target value is equal to or smaller than the second predetermined value while suppressing an increase in the manufacturing cost of the power transmission device, the power width that fluctuates per first period is reduced. It becomes possible to make it smaller.

  In one embodiment of the present invention, at least the first power width may be variably set and stored.

  Accordingly, for example, it is possible to variably set the power width when changing the transmission power according to the type of the power transmission device or the power reception device.

  Moreover, in 1 aspect of this invention, when the said transmission power setting value is larger than a said 1st target value when the said control part is larger than a 2nd target value, the said control part is, When the transmission power is reduced and the transmission power setting value is smaller than the second target value, the transmission power is increased, the transmission power setting value is greater than or equal to the first target value, and the second If the value is less than or equal to the target value, the transmitted power may be changed.

  This makes it possible to maintain the transmission power at a level that is not less than the first target value and not more than the second target value.

  In another aspect of the present invention, a control device used in a power transmission device that transmits power to a power receiving device by contactless power transmission, the control unit controlling a power transmission unit that transmits power to the power receiving device; A communication unit that performs communication processing for receiving communication data transmitted by the power receiving device, and the control unit acquires information on a transmission power setting value based on the communication data, and the transmission power setting value When the difference value with the target value is larger than the predetermined value, the transmission power is changed with a predetermined power width in the first period, and the difference value between the transmission power setting value and the target value is the predetermined value. The following cases relate to a control device that changes the transmitted power with the predetermined power width in a second period longer than the first period.

  In another aspect of the present invention, a control device used in a power transmission device that transmits power to a power receiving device by contactless power transmission, the control unit controlling a power transmission unit that transmits power to the power receiving device; A communication unit that processes communication data received from the power receiving device, and the control unit is configured to output an output voltage of the power receiving unit of the power receiving device and a target value of the output voltage based on the communication data. When the difference value between the output voltage and the target voltage is a first potential difference, the transmission power is changed with a first power width, and the difference between the output voltage and the target voltage is compared. When the value is a second potential difference larger than the first potential difference, the control unit is configured to change the transmitted power with a second power width larger than the first power width.

  Another aspect of the present invention relates to a power transmission device including the control device.

  Another aspect of the invention relates to an electronic apparatus including the control device.

Explanatory drawing of the non-contact electric power transmission system of this embodiment. Explanatory drawing of the electric power transmission transformer of a primary coil and a secondary coil. 2 is a configuration example of a control device, a power transmission device, and a power reception device of the present embodiment. 3 is a detailed configuration example of a control device, a power transmission device, and a power reception device according to the present embodiment. Explanatory drawing of the power transmission voltage control in case a voltage fluctuation range is fixed. Explanatory drawing of the power transmission voltage control in case a voltage fluctuation range is variable. The detailed structural example of a control part. The other detailed structural example of a control part. Explanatory drawing of the update result of a drive voltage control value. 3 shows detailed configuration examples of a power supply voltage setting unit and a power supply voltage control unit. The more detailed structural example of a power supply voltage setting part. Explanatory drawing of an example of the operation | movement sequence of a non-contact electric power transmission system. The signal waveform diagram explaining the operation | movement sequence at the time of landing detection. The signal waveform diagram explaining the operation | movement sequence at the time of removal. The signal waveform diagram explaining the operation | movement sequence at the time of removal. Explanatory drawing of the electric power control method which keeps a rectification voltage constant. Another explanatory view of the electric power control technique which keeps a rectification voltage constant. Explanatory drawing of the communication method by load modulation. Explanatory drawing of the communication structure of the receiving side. Explanatory drawing of the communication method of this embodiment. Explanatory drawing of the format of communication data. Another explanatory view of a format of communication data.

  Hereinafter, this embodiment will be described. In addition, this embodiment demonstrated below does not unduly limit the content of this invention described in the claim. In addition, all the configurations described in the present embodiment are not necessarily essential configuration requirements of the present invention.

1. Non-contact power transmission system FIG. 1A shows an example of a non-contact power transmission system of this embodiment. The charger 500 (one of the electronic devices) includes the power transmission device 10. The electronic device 510 includes the power receiving device 40. The electronic device 510 also includes an operation switch unit 514 (operation unit in a broad sense) and a battery 90. 1A schematically shows the battery 90, the battery 90 is actually built in the electronic device 510. The non-contact power transmission system of the present embodiment is configured by the power transmission device 10 and the power reception device 40 of FIG. 1A.

  Electric power is supplied to the charger 500 via the power adapter 502, and this electric power is transmitted (transmitted) from the power transmitting device 10 to the power receiving device 40 by non-contact power transmission. Thereby, the battery 90 of the electronic device 510 can be charged, and the device in the electronic device 510 can be operated.

  The power source of the charger 500 may be a power source using a USB (USB cable). Various devices can be assumed as the electronic device 510 to which the present embodiment is applied. For example, hearing aids, wristwatches, biological information measuring devices (wearable devices that measure pulse waves, etc.), portable information terminals (smartphones, mobile phones, etc.), cordless telephones, shavers, electric toothbrushes, wrist computers, handy terminals, in-vehicle devices Various electronic devices such as hybrid vehicles, electric vehicles, electric motorcycles, and electric bicycles can be assumed. For example, the control device (power receiving device or the like) of the present embodiment can be incorporated in various moving bodies such as a car, an airplane, a motorcycle, a bicycle, or a ship. The moving body is, for example, a device / device that moves on the ground, in the sky, or on the sea, including a drive mechanism such as a motor or an engine, a steering mechanism such as a steering wheel or rudder, and various electronic devices (on-vehicle devices).

  As schematically shown in FIG. 1B, power transmission from the power transmission device 10 to the power reception device 40 is performed by a primary coil L1 (power transmission coil) provided on the power transmission side and a secondary coil L2 ( This is realized by electromagnetically coupling the receiving coil) to form a power transmission transformer. Thereby, non-contact power transmission becomes possible. As the contactless power transmission method, various methods such as an electromagnetic induction method or a magnetic field resonance method can be adopted.

2. Configurations of Power Transmission Device, Power Reception Device, and Control Device FIG. 2 shows a configuration example of the control devices 20 and 50 of the present embodiment, and the power transmission device 10 and the power reception device 40 including the control devices 20 and 50. The configuration of each of these devices is not limited to the configuration of FIG. 2, and some of the components are omitted, other components (for example, a notification unit) are added, or the connection relationship is changed. Various modifications are possible.

  A power transmission-side electronic device such as the charger 500 of FIG. 1A includes a power transmission device 10. The electronic device 510 on the power receiving side includes a power receiving device 40 and a load 80. The load 80 can include a battery 90 and a power supply target 100. The power supply target 100 is various devices such as a processing unit (DSP or the like), for example. 2 realizes a non-contact power transmission (non-contact power transmission) system in which the primary coil L1 and the secondary coil L2 are electromagnetically coupled to transmit power from the power transmitting apparatus 10 to the power receiving apparatus 40. Is done.

  The power transmission device 10 (power transmission module, primary module) includes a primary coil L1, a power transmission unit 12, and a control device 20. The power transmission unit 12 generates an AC voltage having a predetermined frequency during power transmission and supplies the AC voltage to the primary coil L1. The power transmission unit 12 includes a power transmission driver that drives the primary coil L1, a power supply circuit that supplies power to the power transmission driver (for example, a power supply voltage control unit), and at least one capacitor (capacitor) that forms a resonance circuit together with the primary coil L1. ) Can be included.

  The primary coil L1 (power transmission side coil) is electromagnetically coupled to the secondary coil L2 (power reception side coil) to form a power transmission transformer. For example, when power transmission is necessary, as shown in FIG. 1A and FIG. 1B described above, the electronic device 510 is placed on the charger 500 so that the magnetic flux of the primary coil L1 passes through the secondary coil L2. . On the other hand, when power transmission is unnecessary, the charger 500 and the electronic device 510 are physically separated so that the magnetic flux of the primary coil L1 does not pass through the secondary coil L2.

  The control device 20 of the present embodiment is a control device on the power transmission side in a contactless power transmission system including the power transmission device 10 and the power reception device 40. The control device 20 performs various controls on the power transmission side, and can be realized by an integrated circuit device (IC) or the like. The control device 20 includes a control unit 24 and a communication unit 30. The control device 20 can include a storage unit 23. Modifications such as incorporating the power transmission unit 12 in the control device 20 are also possible.

  The control unit 24 executes various control processes of the control device 20 on the power transmission side. For example, the control unit 24 controls the power transmission unit 12 and the communication unit 30 that transmit power to the power receiving device 40. Specifically, the control unit 24 performs various sequence controls and determination processes necessary for power transmission, communication processing, and the like. The control unit 24 can be realized by a logic circuit generated by an automatic placement and routing method such as a gate array or various processors such as a microcomputer.

  The communication unit 30 performs communication data communication processing with the power receiving device 40. For example, the communication unit 30 performs processing (communication processing) for detecting and receiving communication data from the power receiving device 40.

  The storage unit 23 stores various types of information. The storage unit 23 can be realized by a volatile memory such as a RAM (Random Access Memory), but is not limited thereto. For example, the storage unit 23 may be realized by a nonvolatile memory. Alternatively, the storage unit 23 may be realized by a circuit using a fuse element.

  The power receiving device 40 (power receiving module, secondary module) includes a secondary coil L2 and a control device 50. The control device 50 performs various controls on the power receiving side and can be realized by an integrated circuit device (IC) or the like. The control device 50 includes a power reception unit 52, a control unit 54, a communication unit 46 (load modulation unit 56), and a power supply unit 57. The control device 50 can include a storage unit 48. Modifications such as providing the power receiving unit 52 outside the control device 50 are also possible.

  The power receiving unit 52 receives power from the power transmission device 10. Specifically, the power receiving unit 52 converts the AC induced voltage of the secondary coil L2 into a DC rectified voltage (VCC) and outputs it.

  The power supply unit 57 supplies power to the load 80 based on the power received by the power receiving unit 52. For example, the battery 90 is charged by supplying the power received by the power receiving unit 52. Alternatively, the power supplied from the battery 90 or the power received by the power receiving unit 52 is supplied to the power supply target 100. The power supply unit 57 includes a power supply switch 42. The power supply switch 42 is a switch (switch element, switch circuit) that supplies the power received by the power receiving unit 52 to the load 80. For example, the power supply switch 42 supplies the power received by the power receiving unit 52 to the battery 90 that is the load 80 to charge the battery 90.

  The control unit 54 executes various control processes of the control device 50 on the power receiving side. For example, the control unit 54 controls the communication unit 46 (load modulation unit 56) and the power supply unit 57. Further, the power receiving unit 52 and the storage unit 48 can be controlled. The control unit 54 can be realized by a logic circuit generated by an automatic placement and routing method such as a gate array or various processors such as a microcomputer.

  The communication unit 46 performs communication for transmitting communication data to the power transmission device 10. Alternatively, communication for receiving communication data from the power transmission device 10 may be performed. For example, when the communication unit 46 includes the load modulation unit 56, the communication of the communication unit 46 can be realized by the load modulation unit 56 performing load modulation, for example. For example, the load modulator 56 has a current source, and performs load modulation using this current source. However, the communication method of the communication unit 46 is not limited to load modulation. For example, the communication unit 46 may perform communication by a method other than load modulation using the primary coil L1 and the secondary coil L2. Alternatively, a coil different from the primary coil L1 and the secondary coil L2 may be provided, and communication may be performed by load modulation or other communication methods using the other coil. Alternatively, communication may be performed by proximity wireless communication such as RF.

  The storage unit 48 stores various types of information. The storage unit 48 can be realized by, for example, a nonvolatile memory, but is not limited to this. For example, the storage unit 48 may be realized by a memory (for example, ROM) other than the nonvolatile memory. Alternatively, the storage unit 48 may be realized by a circuit using a fuse element.

  The load 80 includes a battery 90 and a power supply target 100 of the battery 90. However, a modified embodiment in which any one of them is not provided is also possible.

  The battery 90 is, for example, a rechargeable secondary battery, such as a lithium battery (such as a lithium ion secondary battery or a lithium ion polymer secondary battery) or a nickel battery (such as a nickel / hydrogen storage battery or a nickel / cadmium storage battery). The power supply target 100 is, for example, a device (integrated circuit device) such as a processing unit (DSP, microcomputer), and is provided in the electronic device 510 (FIG. 1A) incorporating the power receiving device 40. Device. Note that the power received by the power receiving unit 52 may be directly supplied to the power supply target 100.

3. Detailed Configuration Examples of Power Transmission Device, Power Reception Device, and Control Device FIG. 3 shows detailed configuration examples of the control devices 20 and 50 of the present embodiment, the power transmission device 10 including the control devices 20 and 50, and the power reception device 40. In FIG. 3, detailed description of the same configuration as that of FIG. 2 is omitted.

  In FIG. 3, the power transmission unit 12 includes a first power transmission driver DR1 that drives one end of the primary coil L1, a second power transmission driver DR2 that drives the other end of the primary coil L1, and a power supply voltage control unit 14. Including. Each of the power transmission drivers DR1 and DR2 is realized by, for example, an inverter circuit (buffer circuit) configured by a power MOS transistor. These power transmission drivers DR1 and DR2 are controlled (driven) by the driver control circuit 22 of the control device 20. That is, the control unit 24 controls the power transmission unit 12 via the driver control circuit 22.

  The power supply voltage control unit 14 controls the power supply voltage VDRV of the power transmission drivers DR1 and DR2. For example, the control unit 24 notifies the power supply voltage setting unit 26 of communication data (transmission power setting information) received from the power receiving side. Then, the power supply voltage setting unit 26 controls the power supply voltage control unit 14 based on the transmission power setting information. Thereby, the power supply voltage VDRV supplied to the power transmission drivers DR1 and DR2 is controlled, and, for example, variable control of the transmission power is realized. The power supply voltage control unit 14 can be realized by, for example, a DCDC converter. For example, the power supply voltage control unit 14 performs a step-up operation of a power supply voltage (for example, 5V) from the power supply, generates a power supply driver power supply voltage VDRV (for example, 6V to 15V), and supplies it to the power transmission drivers DR1 and DR2. . Specifically, when the transmission power from the power transmission device 10 to the power reception device 40 is increased, the power supply voltage control unit 14 increases the power supply voltage VDRV supplied to the power transmission drivers DR1 and DR2 and decreases the transmission power. In this case, the power supply voltage VDRV is lowered.

  The notification unit 16 (display unit) notifies (displays) various states of the contactless power transmission system (during power transmission, ID authentication, etc.) using light, sound, images, etc. Or LCD.

  The power transmission side control device 20 includes a driver control circuit 22, a control unit 24, a power supply voltage setting unit 26, a communication unit 30, a clock generation circuit 37, and an oscillation circuit 38. The driver control circuit 22 (pre-driver) controls the power transmission drivers DR1 and DR2. For example, the driver control circuit 22 outputs a control signal (drive signal) to the gates of the transistors constituting the power transmission drivers DR1 and DR2, and drives the primary coil L1 by the power transmission drivers DR1 and DR2. The oscillation circuit 38 is composed of, for example, a crystal oscillation circuit or the like and generates a primary side clock signal. The clock generation circuit 37 generates a drive clock signal that defines a power transmission frequency (drive frequency). The driver control circuit 22 generates a control signal having a given frequency (power transmission frequency) based on the drive clock signal, the control signal from the control unit 24, and the like, and outputs the control signal to the power transmission drivers DR1 and DR2 of the power transmission unit 12. And control. The present embodiment is not limited to the configuration example shown in FIG. 3, and various modifications may be made such as, for example, the power supply voltage setting unit 26 is included in the power transmission unit 12 and the power supply voltage control unit 14 is included in the control device 20. Is possible.

  The power receiving side control device 50 includes a power receiving unit 52, a control unit 54, a load modulation unit 56, a power supply unit 57, a nonvolatile memory 62, and a detection unit 64.

  The power receiving unit 52 includes a rectifier circuit 53 including a plurality of transistors, diodes, and the like. The rectifier circuit 53 converts the AC induced voltage of the secondary coil L2 into a DC rectified voltage VCC and outputs it.

  The load modulation unit 56 (communication unit in a broad sense) performs load modulation. For example, the load modulation unit 56 includes a current source IS, and performs load modulation using the current source IS. Specifically, the load modulation unit 56 includes a current source IS (constant current source) and a switch element SW. The current source IS and the switch element SW are provided in series between, for example, a node NVC of the rectified voltage VCC and a node of GND (low potential side power supply in a broad sense). Then, for example, the switch element SW is turned on or off based on a control signal from the control unit 54, and the current (constant current) of the current source IS flowing from the node NVC to GND is turned on or off, whereby load modulation is performed. Realized.

  Note that one end of the capacitor CM is connected to the node NVC. The capacitor CM is provided as an external component of the control device 50, for example. The switch element SW can be realized by a MOS transistor or the like. This switch element SW may be provided as a transistor constituting the circuit of the current source IS. Further, the load modulation unit 56 is not limited to the configuration shown in FIG. 3, and various modifications such as using a resistor instead of the current source IS are possible.

  The power supply unit 57 includes a charging unit 58 and a discharging unit 60. The charging unit 58 charges the battery 90 (charging control) based on the received power. For example, the charging unit 58 is supplied with a voltage based on the rectified voltage VCC (DC voltage in a broad sense) from the power receiving unit 52 and charges the battery 90. The charging unit 58 can include a power supply switch 42 and a CC charging circuit 59. The CC charging circuit 59 is a circuit that performs CC (Constant-Current) charging of the battery 90.

  The discharging unit 60 performs a discharging operation of the battery 90. For example, the discharging unit 60 performs the discharging operation of the battery 90 and supplies the power from the battery 90 to the power supply target 100. For example, the discharge unit 60 is supplied with the battery voltage VBAT from the battery 90 and supplies the output voltage VOUT to the power supply target 100. The discharge unit 60 can include a charge pump circuit 61. The charge pump circuit 61 steps down the battery voltage VBAT (for example, 1/3 step down) and supplies the output voltage VOUT (VBAT / 3) to the power supply target 100. The discharge unit 60 (charge pump circuit) operates using, for example, the battery voltage VBAT as a power supply voltage.

  The nonvolatile memory 62 (storage unit in a broad sense) is a nonvolatile memory device that stores various types of information. The nonvolatile memory 62 stores various information such as status information of the power receiving device 40, for example. As the nonvolatile memory 62, for example, an EEPROM or the like can be used. As the EEPROM, for example, a MONOS (Metal-Oxide-Nitride-Oxide-Silicon) type memory can be used. For example, a flash memory using a MONOS type memory can be used. Alternatively, another type of memory such as a floating gate type may be used as the EEPROM.

  The detection unit 64 performs various detection processes. For example, the detection unit 64 monitors the rectified voltage VCC, the battery voltage VBAT, and the like, and executes various detection processes. Specifically, the detection unit 64 includes an A / D conversion circuit 65, and a voltage based on the rectified voltage VCC or the battery voltage VBAT, a temperature detection voltage from a temperature detection unit (not shown), or the like is detected. A / D conversion is performed using the digital A / D conversion value obtained. As detection processing performed by the detection unit 64, detection processing of overdischarge, overvoltage, overcurrent, or temperature abnormality (high temperature, low temperature) can be assumed.

  In FIG. 3, when the output voltage VCC of the power receiving unit 52 is higher than the first voltage (VST) and the landing is detected, the load modulation unit 56 starts the load modulation and the removal is detected. If so, stop load modulation. Specifically, the load modulation unit 56 starts load modulation when the landing of the electronic device 510 is detected as shown in FIG. 1A. The power transmission device 10 (control unit 24) starts normal power transmission by the power transmission unit 12 on condition that the power reception device 40 (load modulation unit 56) has started load modulation, for example. When the removal of the electronic device 510 is detected, the load modulation unit 56 stops the load modulation. The power transmission device 10 (the control unit 24) continues normal power transmission by the power transmission unit 12 while the load modulation is continued. That is, when load modulation is not detected, normal power transmission is stopped, and for example, the power transmission unit 12 performs intermittent power transmission for landing detection. In this case, the power receiving side control unit 54 can perform landing detection and removal detection based on the output voltage VCC of the power receiving unit 52.

  In FIG. 3, the communication unit 46 shown in FIG. 2 is realized by a load modulation unit 56 that transmits communication data by load modulation. Specifically, the load modulation unit 56 sets the first load state for the first logical level (for example, “1”) of the communication data (bit of communication data) transmitted to the power transmission device 10 (control device 20). And load modulation is performed so that the load modulation pattern configured in the second load state becomes the first pattern (first bit pattern). On the other hand, for the second logical level (for example, “0”) of communication data (communication data bits) transmitted to the power transmission apparatus 10, the load modulation pattern is different from the first pattern (second pattern). Bit modulation).

  On the other hand, when the load modulation pattern is the first pattern, the communication unit 30 on the power transmission side determines that the communication data has the first logic level and the load modulation pattern is the second pattern. Is determined to be communication data of the second logic level.

  Here, the first pattern is a pattern in which, for example, the width of the first load state period is longer than that of the second pattern. For example, the communication unit 30 samples the load modulation pattern at a given sampling interval from the first sampling point set within the period of the first load state in the first pattern, and gives a given number of bits. Communication data (for example, 16 bits or 64 bits) is captured.

  According to the method using such a load modulation pattern, it is possible to improve the detection sensitivity and the noise resistance of the detection with respect to the load fluctuation caused by the load modulation. As a result, the first voltage that is the communication start voltage (load modulation start voltage) can be set to a low voltage. As a result, it is possible to detect landing over a wide distance range, start communication, and cause the power transmission side to perform control for charging the battery 90 (for example, transmission power control).

  In addition, the power supply unit 57 performs the discharging operation of the battery 90 and the charging unit 58 that charges the battery 90 based on the power received by the power receiving unit 52, and supplies the power from the battery 90 to the power supply target 100. The discharge part 60 to supply is included.

  And the control part 54 (control part of a discharge system) stops the discharge operation of the discharge part 60, when landing is detected. That is, when the landing of the electronic device 510 is detected in FIG. 1A, the discharging operation (supply of VOUT) of the discharge unit 60 is stopped so that the power of the battery 90 is not discharged to the power supply target 100. And the control part 54 makes the discharge part 60 of the electric power supply part 57 perform discharge operation in the removal period (period when the electronic device 510 is removed). With this discharging operation, the power from the battery 90 is supplied to the power supply target 100 via the discharging unit 60.

4). Control of transmitted power In the present embodiment, the power transmission side employs a method of performing power transmission control based on communication data from the power receiving side. Specifically, in the normal power transmission period, the control unit 24 supplies the power supply voltage (drive voltage) VDRV that changes variably based on the transmission power setting information included in the communication data from the power supply voltage control unit 14 to the power transmission driver DR1, Supply to DR2. Thereby, the transmission power of the power transmission unit 12 is variably controlled based on the transmission power setting information. Then, the received power in the power receiving device 40 changes according to the transmitted power.

  Furthermore, in the present embodiment, it is possible to shorten the time until the rectified voltage VCC (received power) in the power receiving device 40 approaches the target voltage (target value) (the time until it stabilizes within the allowable voltage range). To do.

  Specifically, in the present embodiment, the larger the difference between the rectified voltage VCC and the target voltage, the greater the power transmission voltage VH is changed with a larger voltage width. That is, the control unit 24 acquires transmission power setting value information based on communication data, and controls the transmission power of the power transmission unit 12 with a larger power width as the difference between the transmission power setting value and the target value increases.

  Here, the information on the transmission power set value is, for example, information on the rectified voltage VCC (output voltage of the power receiving unit 52). That is, the control unit 24 acquires information on the output voltage (rectified voltage VCC) of the power receiving unit 52 of the power receiving device 40 as information on the transmission power setting value based on the communication data, and acquires the target voltage that is the target value and the power receiving The transmission power of the power transmission unit 12 is controlled with a larger power width as the difference from the output voltage of the unit 52 is larger. Controlling the transmission voltage VH with a large power width increases the speed at which the rectified voltage VCC approaches the target voltage.

  Therefore, it is possible to shorten the time until the received power in the power receiving device 40 approaches the target value. Specifically, as in the example shown in FIG. 5 described later, it is possible to shorten the time until the rectified voltage VCC in the power receiving device 40 approaches the target voltage.

  Here, a comparative example will be described with reference to FIG. In the graph of FIG. 4, the left vertical axis represents the magnitude of the transmission voltage (transmission power) VH (V) and the rectified voltage (reception power) VCC (V) in the power reception device 40. The vertical axis on the right side represents the magnitude of the drive voltage control value Power_control input from the control unit 24 to the power supply voltage setting unit 26 in order to change the drive voltage VDRV, and the horizontal axis represents time (s). . The drive voltage control value Power_control is a value representing the voltage level of the drive voltage VDRV, and can be raised or lowered by a given step width. For example, when the drive voltage control value Power_control is a value represented by 8 bits, the drive voltage control value Power_control can take an integer value from 0 to 255 and can be changed by one. Each value of 0 to 255 is associated with each value of the drive voltage VDRV. Note that a unit for changing the drive voltage control value Power_control in one transmission voltage control is called a step width. In the case of FIG. 4, the step width is fixed to 1. That is, when the transmission voltage VH is increased, +1 is added to the drive voltage control value Power_control in one transmission voltage control, and when the transmission voltage VH is decreased, the drive voltage control is performed in one transmission voltage control. Add -1 to the value Power_control. In this case, two target voltages of the first target voltage target_H (V) and the second target voltage target_L (V) are provided as target voltages of the rectified voltage VCC so that the rectified voltage VCC is stabilized between the target_H and the target_L. Next, the power transmission voltage VH is controlled.

  Specifically, in the example of FIG. 4, the communication unit 30 of the power transmission device 10 receives the communication data transmitted from the power reception device 40 and outputs the communication data to the control unit 24. And the control part 24 specifies the information of the rectified voltage VCC contained in the acquired communication data. Further, the control unit 24 determines the drive voltage control value Power_control so that the rectified voltage VCC approaches the target voltage at each timing indicated by the circle of the Power_control series data in FIG. Output. Next, the drive voltage VDRV output from the power supply voltage control unit 14 to the power transmission drivers DR1 and DR2 is set by the power supply voltage setting unit 26 based on the acquired drive voltage control value Power_control. Then, the power transmission drivers DR1 and DR2 transmit power to the power receiving device 40 with the power transmission voltage VH corresponding to the drive voltage VDRV. Thus, the control unit 24 controls the transmission voltage VH by changing the drive voltage VDRV supplied as power to the power transmission drivers DR1 and DR2 of the power transmission unit 12.

  Thereby, it becomes possible to control the drive voltage VDRV of the power transmission unit 12 to bring the rectified voltage VCC (the output voltage of the power reception unit 52) close to the target voltage.

  Further, as described above, in the example of FIG. 4, the step width of the drive voltage control value Power_control that is changed at a time is the same (=) when the transmission voltage VH (or drive voltage VDRV) is increased or decreased. Corresponding to this, the voltage fluctuation width (power fluctuation width) of the transmission voltage VH (or drive voltage VDRV) is also constant. In the following, the voltage width (power width) that is varied in one voltage variation control is referred to as voltage variation width (power variation width).

  Therefore, as shown in FIG. 4, when the transmission voltage VH is changed with the same voltage width, it takes time until the rectified voltage VCC approaches the target voltage when the rectified voltage VCC is away from the target voltage. End up.

  Therefore, as described above, in the example of FIG. 5, the transmission voltage VH is changed with a larger voltage width as the difference between the rectified voltage VCC and the target voltage is larger.

  For example, when the difference value (absolute value) between the transmission power setting value and the target value is larger than the first predetermined value, the control unit 24 controls the transmission power with the first power width and sets the transmission power setting. When the difference value (absolute value) between the value and the target value is equal to or smaller than the first predetermined value and larger than the second predetermined value, the transmission power is reduced with the second power width smaller than the first power width. Control.

  A specific example is shown in FIG. In the example of FIG. 5, when the control unit 24 has a difference value between the rectified voltage VCC, which is transmission power setting value information, and the first target voltage target_H, which is a target value, greater than a first predetermined value JUDGE_H. If it is determined, the transmission voltage VH is varied with the first power width for one voltage variation control. In this case, the control unit 24 varies the drive voltage control value Power_control with the first step width in one voltage control. For example, in the example of FIG. 5, the first step width is 4, which is larger than the step width (= 1) in the above-described example of FIG. Thereby, the power transmission voltage VH fluctuates more than the example of FIG. 4 according to the step width of the drive voltage control value Power_control. As a result, as compared with the example of FIG. 4, it is possible to shorten the time taken until the difference value between the rectified voltage VCC and the first target voltage target_H becomes the first predetermined value JUDGE_H.

  In the example of FIG. 5, the control unit 24 has a difference value (absolute value) between the rectified voltage VCC and the first target voltage target_H that is equal to or less than the first predetermined value JUDGE_H and larger than the second predetermined value JUDGE_L. In this case, the transmission power is controlled with the second power width. In this case, the control unit 24 varies the drive voltage control value Power_control with the second step width in one voltage variation control. For example, in the example of FIG. 5, the second step width is 1 as in the example of FIG. The second power width is a power width smaller than the first power width described above, and is the same as the power width shown in FIG. 4, for example. Thereby, as will be described later, it is possible to prevent the rectified voltage VCC from becoming lower than the first target voltage target_H and the second target voltage target_L.

  Further, as described above, there is a time lag between the change in the transmitted power in the power transmission device 10 and the change in the received power in the power reception device 40. Therefore, before the influence (power fluctuation) based on the change in the transmitted power appears in the received power (for example, the rectified voltage VCC in FIG. 3), the power receiving device transmits information on the received power before the change to the power transmitting device 10. There is. In this case, for example, the power transmission device 10 determines that the received power has not yet approached the target voltage based on the notified received power before the power fluctuation, and further changes the transmitted power, resulting in the received power. May pass the target voltage.

  Here, it returns to description of FIG. 4 once again. As described above, in the example of FIG. 4, the step width of the drive voltage control value Power_control is fixed at 1. For this reason, when the rectified voltage VCC approaches the target voltage, the rectified voltage VCC falls below the target_L as shown by P1 in FIG. 4 due to the time loss between the fluctuations in the transmission voltage and the reception voltage described above. As shown in P2 of FIG. 4, it may exceed target_H. In this case, it may take time for the rectified voltage VCC to stabilize between the target_H and the target_L, or the rectified voltage VCC may not converge to a value between the target_H and the target_L indefinitely.

  On the other hand, when the rectified voltage VCC approaches the target voltage so that the rectified voltage VCC does not move away from the target voltage in the opposite direction after the rectified voltage VCC once approaches the target voltage, the transmission voltage VH It is conceivable to reduce the voltage fluctuation range. For example, in the example of FIG. 4, if the step width for decreasing the drive voltage control value Power_control is changed from −1 to −0.5, −0.25, etc. from around P3, the fluctuation range of the transmission voltage VH is also reduced. It seems to be. However, the power supply voltage setting unit 26 in this embodiment is realized by a configuration as shown in FIG. Therefore, as in the example described above with reference to FIG. 5, there is no problem in increasing the voltage fluctuation range of the transmission voltage VH, but in order to make it possible to cope with voltage fluctuation control in which the voltage fluctuation range is further reduced. May increase the manufacturing cost of the power supply voltage setting unit 26.

  Therefore, in the present embodiment, it is possible to shorten the time until the rectified voltage VCC in the power receiving device 40 is stabilized near the target voltage while suppressing an increase in manufacturing cost of the power transmitting device 10.

  Specifically, when the difference value (absolute value) between the transmission power set value and the target value is equal to or smaller than the first predetermined value and larger than the second predetermined value, the control unit 24 performs the first period. In the second period longer than the first period, when the transmission power for the second power width is changed and the difference value between the transmission power set value and the target value is equal to or less than the second predetermined value. The transmission power for the second power width is changed.

  A specific example is shown in FIG. In the example of FIG. 5, the control unit 24 has a case where the difference value between the rectified voltage VCC and the first target voltage target_H is equal to or smaller than the first predetermined value JUDGE_H and larger than the second predetermined value JUDGE_L (for example, FIG. 5). In the first period TM1, the transmission voltage VH is changed with the above-described second power width during the period indicated by P4. The operation of the control unit 24 in this case is as described above.

  On the other hand, when the difference value between the rectified voltage VCC and the first target voltage target_H is equal to or smaller than the second predetermined value JUDGE_L (for example, the period indicated by P5 in FIG. 5), the control unit 24 In the second period TM2, the transmission voltage VH is changed with the second power width described above. As shown in FIG. 5, the second period TM2 is longer than the first period TM1. In this case, the control unit 24 changes the period during which the drive voltage control value Power_control is changed from the first period TM1 to the second period TM2.

  More specifically, in the period indicated by P5 in FIG. 5, the drive voltage control value Power_control is set to the step width every time when the second period TM2, which is (about) four times as long as the first period TM1, elapses. It can be said that the control unit 24 determines whether to raise, lower, or not change by 1. Therefore, when viewed in the first period TM1, the drive voltage control value Power_control is varied with a step width of (about) 1/4. A method for realizing this control will be described later with reference to FIGS.

  As described above, when the difference value between the rectified voltage VCC and the first target voltage is equal to or smaller than the second predetermined value JUDGE_L, the voltage fluctuation width per first period TM1 can be further reduced. Become. Further, as described above, since the voltage fluctuation width of the drive voltage VDRV output from the power supply voltage control unit 14 is not reduced, an increase in manufacturing cost of the power supply voltage setting unit 26 can be suppressed, In addition, the voltage fluctuation width of the transmission voltage VH per first period TM1 can be reduced in a pseudo manner.

  In the example of FIG. 5, both the switching process of the first power width and the second power width and the switching process of the period for changing the transmission power (the first period and the second period) are performed. However, the present embodiment is not limited thereto, and at least one of the processes may be performed. For example, the power fluctuation range of the transmission power may be constant, and only the period for changing the transmission power may be changed. In addition, as described above, the present embodiment can also employ a method of reducing the step width itself of the drive voltage control value Power_control.

  In addition, when the first target value is larger than the second target value and the transmission power setting value is larger than the first target value, the control unit 24 decreases the transmission power and sets the transmission power setting value. Is smaller than the second target value, the transmission power is increased, and when the transmission power setting value is not less than the first target value and not more than the second target value, the transmission power is not changed. For example, in the example of FIG. 5, the first target voltage target_H is larger than the second target voltage target_L. Then, the control unit 24 reduces the transmission voltage when the rectified voltage VCC is higher than the first target voltage target_H, and reduces the transmission voltage VH when the rectified voltage VCC is lower than the second target voltage target_L. increase. Furthermore, the control unit 24 does not change the transmission voltage VH when the rectified voltage VCC is equal to or higher than the first target voltage target_H and equal to or lower than the second target voltage target_L.

  As a result, the power transmission voltage VH can be maintained at a level equal to or higher than the first target voltage target_H and lower than the second target voltage target_L. In the description of FIG. 5 described above, the case where the rectified voltage VCC is equal to or higher than the first target voltage target_H is exemplified. However, when the rectified voltage VCC is equal to or lower than the second target voltage target_L, the first target is used. The above-described processing can be performed by replacing the voltage target_H with the second target voltage target_L.

  Next, detailed configurations of the control unit 24, the power supply voltage setting unit 26, and the power supply voltage control unit 14 in the case where the above processing is performed will be described with reference to FIGS. First, a configuration example of the control unit 24 and the like is shown in FIG.

  As shown in FIG. 6, the control unit 24 includes a data comparison circuit 241, a change amount setting circuit 242, a change time setting circuit 243, and a data setting circuit 244. The storage unit 23 includes a determination parameter setting register 231. The determination parameter setting register 231 stores at least a first power width that is variably set. In the example of FIG. 6, the determination parameter setting register 231 includes the first target voltage target_H, the second target voltage target_L, the first predetermined value JUDGE_H, the second predetermined value JUDGE_L, and the first The power width STEPH and the second power width STEPL are stored. The first power width STEPH and the second power width STEPL may be, for example, the voltage fluctuation width of the transmission voltage VH, the voltage fluctuation width of the drive voltage VDRV, or the drive voltage control value. It may be the step width of Power_control. Thereby, for example, according to the types of the power transmission device 10 and the power receiving device 40, it is possible to variably set the power width when changing the transmission power.

  The data comparison circuit 241 acquires information on the rectified voltage VCC in the power receiving device 40 from the communication unit 30, and receives information on the first target voltage target_H and information on the second target voltage target_L from the determination parameter setting register 231. get. Then, the data comparison circuit 241 performs a process of comparing the rectified voltage VCC and the first target voltage target_H, and a process of comparing the rectified voltage VCC and the second target voltage target_L, so that the rectified voltage VCC and the first target voltage are compared. The difference value ΔVH between the voltage target_H and the difference value ΔVL between the rectified voltage VCC and the second target voltage target_L are output to the change amount setting circuit 242.

  The change amount setting circuit 242 and the change time setting circuit 243 are supplied from the determination parameter setting register 231 with the first predetermined value JUDGE_H, the second predetermined value JUDGE_L, the first power width STEPH, and the second power width STEPL. Get various information. Further, the change amount setting circuit 242 acquires the above-described difference values ΔVH and ΔVL from the data comparison circuit 241. Then, as described above, the change amount setting circuit 242 determines the step width ΔDA of the drive voltage control value Power_control based on the acquired various information, and outputs it to the data setting circuit 244. In addition, the change time setting circuit 243 determines a period time (for example, the first period TM1 and the second period TM2 in FIG. 5 described above) for changing the drive voltage control value Power_control based on the acquired various pieces of information. To the data setting circuit 244.

  The data setting circuit 244 specifies, for example, an 8-bit drive voltage control value Power_control (DA [7: 0]) based on the step width ΔDA acquired from the change amount setting circuit 242. Then, the data setting circuit 244 outputs an 8-bit drive voltage control value Power_control (DA [7: 0]) to the power supply voltage setting unit 26 in the output period time acquired from the change time setting circuit 243. Note that the output period of the drive voltage control value Power_control may be fixed. In the following description, DA [i: j] represents a bit string from the i-th bit to the j-th bit from the bottom of the n-bit drive voltage control value Power_control (i, j, n is an integer of 0 ≦ j <i <n), and DA [i] represents the i-th bit of the drive voltage control value Power_control. The same applies to the step width ΔDA.

  In addition, the control unit 24 may be configured as shown in FIG. Specifically, the control unit 24 of FIG. 7 includes a data comparison circuit 241, a change amount setting circuit 242, and a data setting circuit 244. The control unit 24 shown in FIG. 7 does not include the change time setting circuit 243 and the point that the normal output period TIME (fixed value) of the drive voltage control value Power_control is input to the data setting circuit 244 is shown in FIG. Different from the control unit 24.

  In this case, for example, the data setting circuit 244 sets the 11-bit drive voltage control value Power_control (DA [10: 0]), and for example, the change amount setting circuit 242 sets the step width ΔDA of the 11-bit drive voltage control value Power_control. [10: 0] is set. In this case, among the 11-bit drive voltage control value Power_control (DA [10: 0]), the upper 8 bits (DA [10: 3]) are integer values of 0 to 255 as in the above-described example. The lower 3 bits DA [2: 0] represent the decimal part of the drive voltage control value Power_control. The same applies to the step width ΔDA [10: 0] of the drive voltage control value Power_control. Then, the data setting circuit 244 outputs only the upper 8 bits (DA [10: 3]) of the 11-bit drive voltage control value Power_control (DA [10: 0]) to the power supply voltage setting unit 26.

  Here, an example of a more specific processing flow will be described with reference to FIGS. FIG. 8 shows the control result of the drive voltage control value Power_control (DA [10: 0]) and the step width ΔDA [10: 0] at P4 and P5 in FIG. First, in the period indicated by P4 in FIG. 5, the change amount setting circuit 242 sets the step width ΔDA [10: 0] to 1, and sets the step width ΔDA [10: 0] = 1 for each output period TIME. Output to the circuit 244. Then, the data setting circuit 244 updates the drive voltage control value Power_control (DA [10: 0]) based on the acquired step width ΔDA [10: 0], and the upper 8 bits (ΔDA [10: 3]). ) Are sequentially output to the power supply voltage setting circuit 26 every output period TIME. For example, in the example of FIG. 8, DA [10: 0] is updated from 22 to 21, 20, and 19. Thereafter, when the period shifts to a period indicated by P5 in FIG. 5, the change amount setting circuit 242 sets the step width ΔDA [10: 0] to 0.25 (0000 0000 010 in binary notation) and outputs it. Also at this time, the data setting circuit 244 continues to update the drive voltage control value Power_control based on the acquired step width ΔDA [10: 0]. However, as described above, the data setting circuit 244 outputs the power supply voltage setting circuit 26 to the upper 8 bits (DA [10: 2] of the 11-bit drive voltage control value Power_control (DA [10: 0]). ]) Only. Therefore, the drive voltage control value Power_control (DA [10: 2] = 18) having the same value is output in a period corresponding to (about) four times the given output period TIME. In other words, it can be said that the step width per given output period TIME has become (about) 1/4.

  In addition, for example, if the step width ΔDA [10: 0] = 0.5 (0000 0000 100 in binary notation), the same value DA is obtained in a period corresponding to (about) twice the given output period TIME. [10: 2] is output, and if the step width ΔDA [10: 0] = 0.125 (binary notation 0000 0000 001), (approximately) 8 times the given output period TIME In the period corresponding to, DA [10: 2] having the same value is output.

  As a result, the same effect is obtained as when the drive voltage control value Power_control is changed by ± 1/2, ± 1/4, or ± 1/8 in a pseudo manner per original output period TIME. be able to. In the present embodiment, the number of bits of the drive voltage control value Power_control is not limited to 8 bits, and the number of bits of the step width is not limited to 11 bits.

  Next, detailed configuration examples of the power supply voltage setting unit 26 and the power supply voltage control unit 14 are shown in FIGS. 9 and 10.

  The power supply voltage setting unit 26 is a resistance dividing circuit as shown in FIG. 9, and includes a resistor RA provided between the first output terminal AOUT (first output node) and the node N1, a node N1 and the ground GND. And a variable resistor RB provided between the two. The node N1 is connected to the second output terminal VFB (second output node).

  As shown in FIG. 9, the power supply voltage control unit 14 includes an input terminal TIN to which the input voltage VIN is input, a resistor RC, an inductor La (coil), a diode D1, a capacitor C1 (capacitor), A step-up DCDC converter CV, an N-type transistor (nMOS) nM, and an output terminal TOUT are included. The resistor RC is provided between the input terminal TIN and the node N2, and the inductor La is provided between the node N2 and the node N3. The diode D1 has an anode connected to the node N3 and a cathode connected to the node N4. The capacitor C1 is provided between the node N4 and the ground GND. The step-up DCDC converter CV has a VDD terminal, an ADJ terminal, a VO terminal, and a GC terminal, the VDD terminal is connected to the node N2, and the ADJ terminal is connected to the output terminal VFB of the power supply voltage setting unit 26. The VO terminal is connected to the output terminal AOUT of the power supply voltage setting unit 26 and the node N4, and the GC terminal is connected to the gate of the N-type transistor nM. The N-type transistor nM has a drain connected to the node N3 and a source connected to the ground GND. The output terminal TOUT is connected to the power transmission drivers DR1 and DR2 in FIG. 3 and outputs a drive voltage VDRV that drives the power transmission drivers DR1 and DR2.

In the circuit as shown in FIG. 9, the drive voltage VDRV can be expressed by the following equation (1). In equation (1), V _ADJ is the voltage at the ADJ terminal of the step-up DCDC converter CV, R _RA is the resistance value of the resistor RA, and R _RB is the resistance value of the variable resistor RB.

VDRV = V _ADJ × (R _RA + R _RB ) / R _RB (1)
In this case, the power supply voltage control unit 14 configured as shown in FIG. 9 operates to keep the voltage V _ADJ at the ADJ terminal constant. Specifically, the step-up DCDC converter CV outputs an on / off signal of the N-type transistor nM from the GC terminal, for example. Then, the step-up DCDC converter CV performs modulation control of the on / off signal (for example, PWM: Pulse Width Modulation), so that the voltage V _{ADJ at the} ADJ terminal becomes the reference voltage V _ref (a constant value). In addition, the drive voltage VDRV is controlled. As an example, the step-up DCDC converter CV includes, for example, a triangular wave generation circuit, an error amplification amplifier, and a PWM signal output circuit. The triangular wave generation circuit generates a triangular wave, and the error amplification amplifier amplifies an error between the voltage V _ADJ and the reference voltage V _ref . The PWM signal output circuit compares the triangular wave generated by the triangular wave generation circuit with the output of the error amplification amplifier and outputs a PWM signal.

In the example of FIG. 9, the resistance value R _RA of the resistor _RA is also constant. Therefore, the drive voltage VDRV in accordance with the above equation (1) is determined by the resistance value _{R RB} of the variable resistor RB.

  Here, a more specific configuration example of the power supply voltage setting unit 26 is shown in FIG. The power supply voltage setting unit 26 shown in FIG. 10 includes a resistor R1 corresponding to the resistor RA in FIG. 9, a base resistor R2, eight adjustment resistors RA0 to RA7, eight N-type transistors nM0 to nM7, and It is comprised by. Each of the resistors RA0 to RA7 forms a series circuit (DC0 to DC7) with each N type transistor of the N type transistors nM0 to nM7, and each series circuit (DC0 to DC7) is connected in parallel with the resistor R2. Has been. The variable resistor RB shown in FIG. 9 is realized by the resistor R2 and the series circuits DC0 to DC7.

  Specifically, the connection relationship in the power supply voltage setting unit 26 in FIG. 10 will be described. The resistor R1 is provided between the output terminal AOUT and the output terminal VFB. The resistor R2 is provided between the output terminal VFB and the ground GND, and is connected in series with the resistor R1. The resistor RA0 has one end connected to the output terminal VFB and the other end connected to the drain of the N-type transistor nM0. The N-type transistor nM0 has a source connected to the ground GND and a gate connected to the data setting circuit 244 of the control unit 24 in FIG. The same applies to the other series circuits DC1 to DC7.

In this case, for example, as shown in FIG. 6, the 8-bit drive voltage control value Power_control (DA [DA [] is output from the data setting circuit 244 to the power supply voltage setting unit 26 at intervals of the output period time set in the change time setting circuit 243. 7: 0]) will be described. As an example, a signal corresponding to the 0th bit (least significant bit) of the 8-bit drive voltage control value Power_control (DA [7: 0]) is applied to the gate of the N-type transistor nM0 from the data setting circuit 244 in FIG. DA [0] is input. At this time, when the value (logic level) of the signal DA [0] is 1, the data setting circuit 244 applies an H level voltage to the gate of the N-type transistor nM0, and the value of the signal DA [0] ( When the logic level is 0, the data setting circuit 244 applies an L level voltage to the gate of the N-type transistor nM0. When the signal level of the DA [0] is at the H level, N type transistor nM0 is turned on, the resistance value _{R RB} of the variable resistor RB is changed according to the resistance value _{R RA0} resistor RA0. On the other hand, when the signal level of DA [0] is L, the N-type transistor nM0 is turned off. The same applies to the other series circuits DC1 to DC7.

Therefore, for example, when 0000 0001 (binary notation) is input to the power supply voltage setting unit 26 as the drive voltage control value Power_control (DA [7: 0]), the N-type transistor nM0 is turned on, and the N-type transistor The transistors nM1 to nM7 are turned off. Accordingly, the resistance value _{R RB} of the variable resistor RB has a value shown by the following formula (2).

R _RB = 1 / (1 / R _R2 + 1 / R _RA0 )) (2)
For example, when 0000 0101 (binary notation) is input to the power supply voltage setting unit 26 as the drive voltage control value Power_control (DA [7: 0]), the N-type transistors nM0 and nM2 are turned on. N-type transistors nM1, nM3 to nM7 are turned off. Accordingly, the resistance value _{R RB} of the variable resistor RB has a value shown by the following formula (3).

_{R RB = 1 / (1 /} R R2 + 1 / R RA0 + 1 / R RA2)) ... (3)
As described above, the drive voltage VDRV can be variably controlled by controlling the resistance value of the variable resistor RB using the value of the drive voltage control value Power_control.

5. Next, an example of the entire operation sequence of the contactless power transmission system of the present embodiment will be described. FIG. 11 is a diagram for explaining the outline of the operation sequence.

  In A <b> 1 of FIG. 11, the electronic device 510 having the power receiving device 40 is not placed on the charger 500 having the power transmitting device 10 and is in a removed state. In this case, the standby state is entered. In this standby state, the power transmission unit 12 of the power transmission device 10 performs intermittent power transmission for landing detection, and enters a state in which the landing of the electronic device 510 is detected. In the standby state, in the power receiving device 40, the discharge operation to the power supply target 100 is on, and the power supply to the power supply target 100 is enabled. As a result, the power supply target 100 such as a processing unit can be operated by being supplied with power from the battery 90.

  As shown in A2 of FIG. 11, when electronic device 510 is placed on charger 500 and landing is detected, a communication check & charge state is entered. In this communication check & charge state, the power transmission unit 12 of the power transmission device 10 performs normal power transmission that is continuous power transmission. At this time, normal power transmission is performed while performing power control in which the power varies variably according to the state of power transmission. Control based on the state of charge of the battery 90 is also performed. The state of power transmission is a state determined by, for example, the positional relationship (distance between the coils) of the primary coil L1 and the secondary coil L2, and can be determined based on information such as the rectified voltage VCC of the power receiving unit 52, for example. The state of charge of the battery 90 can be determined based on information such as the battery voltage VBAT.

  In the communication check & charge state, the charging operation of the charging unit 58 of the power receiving device 40 is turned on, and the battery 90 is charged based on the power received by the power receiving unit 52. Further, the discharging operation of the discharging unit 60 is turned off, and the power from the battery 90 is not supplied to the power supply target 100. In the communication check & charge state, communication data is transmitted to the power transmission side by load modulation of the load modulation unit 56. For example, communication data including information such as transmission power setting information (VCC, etc.), charging state information (VBAT, various status flags, etc.), temperature, etc. is received from the power receiving side by constant load modulation during the normal power transmission period. Sent to the power transmission side.

  As shown in A3 of FIG. 11, when full charge of the battery 90 is detected, a full charge standby state is entered. In the full charge standby state, the power transmission unit 12 is in a state of detecting the removal of the electronic device 510 by performing, for example, intermittent power transmission for removal detection. In addition, the discharge operation of the discharge unit 60 remains off, and the power supply to the power supply target 100 remains disabled.

  Then, when removal of the electronic device 510 is detected as indicated by A4 in FIG. 11, the electronic device 510 enters a use state as indicated by A5, and the discharge operation on the power receiving side is turned on. Specifically, the discharge operation of the discharge unit 60 is switched from off to on, and the power from the battery 90 is supplied to the power supply target 100 via the discharge unit 60. As a result, power from the battery 90 is supplied, the power supply target 100 such as a processing unit operates, and the user can use the electronic device 510 normally.

  As described above, in the present embodiment, as shown by A1 in FIG. 11, when the landing of the electronic device 510 is detected, normal power transmission is performed, and constant load modulation is performed during the normal power transmission period. When the landing is detected, the discharge operation of the discharge unit 60 is stopped. In this constant load modulation, communication data including information for power control on the power transmission side and information indicating the status on the power reception side is transmitted from the power reception side to the power transmission side. For example, by communicating information for power control (transmission power setting information), it is possible to realize optimal power control according to, for example, the positional relationship between the primary coil L1 and the secondary coil L2. In addition, an optimal and safe charging environment can be realized by communicating information representing the status of the power receiving side. In the present embodiment, the normal power transmission is continued while the load modulation is continued, and the discharge operation of the discharge unit 60 remains off.

  In this embodiment, as shown by A3 in FIG. 11, when full charge of the battery 90 is detected, normal power transmission stops and intermittent power transmission for removal detection is performed. And as shown to A4 and A5, when removal is detected and it becomes a removal period, the discharge operation of the discharge part 60 will be performed. As a result, the power from the battery 90 is supplied to the power supply target 100, and the normal operation of the electronic device 510 becomes possible. Landing detection and removal detection are performed based on the output voltage VCC of the power receiving unit 52.

  As described above, in the present embodiment, the discharging operation to the power supply target 100 is turned off during the charging period (normal power transmission period) of the battery 90 of the electronic apparatus 510. Can be prevented from being consumed.

  When the removal of the electronic device 510 is detected, the normal power transmission is switched to the intermittent power transmission, and the discharge operation to the power supply target 100 is turned on. When the discharge operation is turned on in this way, the power from the battery 90 is supplied to the power supply target 100, and the normal operation of the power supply target 100 such as a processing unit (DSP) becomes possible. In this way, for example, in an electronic device 510 (for example, an electronic device worn by a user such as a hearing aid or a wearable device) that does not operate during a charging period in which the electronic device 510 is placed on the charger 500. Therefore, a suitable contactless power transmission operation sequence can be realized.

  FIG. 12, FIG. 13, and FIG. 14 are signal waveform diagrams for explaining the details of the operation sequence of the contactless power transmission system of this embodiment.

  B1 in FIG. 12 is the standby state of A1 in FIG. 11, and intermittent power transmission for landing detection is performed. That is, power transmission is performed at intervals of the period TL2 at intervals of the period TL1. The interval of TL1 is 3 seconds, for example, and the interval of TL2 is 50 milliseconds, for example. In B2 and B3 of FIG. 12, the rectified voltage VCC is equal to or lower than the voltage VST (lower than the first voltage), so communication by load modulation is not performed.

  On the other hand, since the rectified voltage VCC exceeds the voltage VST (for example, 4.5 V) in B4, the load modulation unit 56 starts load modulation as shown in B5. That is, in B2 and B3, the coils L1 and L2 are not sufficiently electromagnetically coupled, but in B4, the coils L1 and L2 are properly electromagnetically coupled as shown in FIG. 1B. For this reason, the rectified voltage VCC rises, exceeds the voltage VST, and load modulation starts as indicated by B5. And by this load modulation, communication data as shown to B6 is transmitted to the power transmission side. The load modulation of B5 is started when the rectified voltage VCC is increased by the intermittent power transmission for landing detection shown in B7.

  Specifically, the power receiving side transmits landing detection dummy data (eg, “0” of 64 bits). The power transmission side detects this dummy data (for example, detection of 8-bit “0”) to detect the landing on the power receiving side, and starts normal power transmission (continuous power transmission) as indicated by B7.

  Next, the power receiving side transmits ID information and rectified voltage VCC information. A simple authentication process is realized by the power transmission side responding to the transmission of the ID information.

  Further, the power transmission side receives transmission power setting information that is information on the rectified voltage VCC, and controls the transmission power as described above. The control of the transmission power on the power transmission side increases the rectified voltage VCC as indicated by B8. As shown in B9, when VCC exceeds the voltage VCCL (second voltage), charging of the battery 90 is started.

  Thus, in this embodiment, the voltage VST for starting load modulation (communication) can be set low. Thereby, generation | occurrence | production of malfunctions, such as a pressure | voltage resistant abnormality by setting the drive voltage on the power transmission side high, can be suppressed. Then, by transmitting the transmission power setting information (VCC) to the power transmission side by the started load modulation, the transmission power on the power transmission side is controlled, and by this transmission power control, the rectified voltage as shown in B8 VCC rises. Then, when the rectified voltage VCC rises and exceeds the voltage VCCL that is a chargeable voltage as indicated by B9, charging of the battery 90 starts. Therefore, it is possible to realize both landing detection in a wide distance range and suppression of occurrence of defects such as abnormal pressure resistance.

  In C1 of FIG. 13, the electronic device 510 is removed during the normal power transmission period in which the battery 90 is charged. The removal of C1 is removal before the battery 90 is fully charged (full charge flag = L level) as indicated by C2 and C3.

  When the electronic device 510 is removed as described above, the power on the power transmission side is not transmitted to the power receiving side, and the rectified voltage VCC decreases. As shown in C4, for example, when VCC <3.1V, the load modulation by the load modulation unit 56 is stopped as shown in C5. When the load modulation is stopped, normal power transmission by the power transmission unit 12 is stopped as indicated by C6.

  Further, when the rectified voltage VCC decreases and falls below, for example, 3.1 V, which is a determination voltage, discharging of the start capacitor on the power receiving side (not shown) starts. The start capacitor is a capacitor for starting the discharge operation on the power receiving side (for measuring the starting period), and is provided as an external component of the control device 50 on the power receiving side, for example. When the start-up period TST elapses after the rectified voltage VCC falls below the determination voltage (3.1 V), the discharge operation of the discharge unit 60 is switched from off to on as indicated by C8, and the power from the battery 90 is It is supplied to the supply object 100. In addition, after stopping normal power transmission, the power transmission unit 12 performs intermittent power transmission for landing detection as indicated by C9.

  In the present embodiment, a charging system control unit and a discharging system control unit are provided as the control unit 54 on the power receiving side. The control unit of the charging system operates by being supplied with a power supply voltage based on the rectified voltage VCC (output voltage) of the power receiving unit 52. On the other hand, the control unit and the discharge unit 60 of the discharge system operate by being supplied with the power supply voltage by the battery voltage VBAT. Control of charge / discharge of the start capacitor and control of discharge operation of the discharge unit 60 (on / off control) are performed by the discharge system control unit.

  In D1 of FIG. 14, the full charge flag is at the H level which is the active level, and the full charge of the battery 90 is detected. When full charge is detected in this manner, intermittent power transmission for removal detection after full charge is performed as indicated by D2. That is, power transmission is performed at intervals of the period TR2 at intervals of the period TR1. The interval of TR1 is 1.5 seconds, for example, and the interval of TR2 is 50 milliseconds, for example. The interval TR1 for intermittent power transmission for removal detection is shorter than the interval TL1 for intermittent power transmission for landing detection.

  Due to this intermittent power transmission for removal detection, the rectified voltage becomes VCC> VST as indicated by D3 and D4 in FIG. 14, and load modulation is performed as indicated by D5 and D6. The power transmission side can detect that the electronic device 510 has not yet been removed by detecting this load modulation (such as empty communication data).

  The interval (for example, 1.5 seconds) of the intermittent power transmission period TR1 for removal detection is shorter than the interval (for example, longer than 3 seconds) of the start-up period TST indicated by D7 set by the start capacitor. Therefore, in a state where the electronic device 510 is not removed, the voltage (charge voltage) of the start capacitor does not fall below the threshold voltage VT for turning on the discharge operation, and the discharge operation is switched from OFF to ON as indicated by D8. There is no switching.

  On the other hand, in D9, the electronic device 510 is removed. And after completion | finish of period TR2 of intermittent power transmission for removal detection shown to D4, as shown to D10, since the rectification voltage VCC falls below 3.1V which is a determination voltage, the measurement of the starting period TST shown to D7 starts. . In D11, the voltage of the start capacitor is lower than the threshold voltage VT for turning on the discharge operation, and the elapse of the starting period TST is detected. Thereby, the discharge operation of the discharge unit 60 is switched from off to on, and the power from the battery 90 is supplied to the power supply target 100. Further, as shown at D12, intermittent power transmission for detecting the landing of the electronic device 510 is performed.

  As described above, in the present embodiment, normal power transmission by the power transmission unit 12 is started as shown in B7 on the condition that the power receiving device 40 starts load modulation as shown in B5 of FIG. And while the load modulation of B5 is continued, the normal power transmission shown in B7 is continued. Specifically, when load modulation is not detected as indicated by C5 in FIG. 13, normal power transmission by the power transmission unit 12 is stopped as indicated by C6. And as shown to C9, the intermittent transmission for the landing detection by the power transmission part 12 comes to be performed.

  As described above, in the present embodiment, the normal power transmission is started on the condition that the load modulation is started, the normal power transmission is continued while the load modulation is continued, and the normal power transmission is stopped when the load modulation is not detected. A sequence is adopted. In this way, contactless power transmission and communication by load modulation can be realized with a simple and simple operation sequence. In addition, by performing communication based on constant load modulation during the normal power transmission period, it is possible to realize efficient contactless power transmission according to the state of power transmission.

6). Example of Transmission Power Control In the present embodiment, the control unit 24 transmits the power supply voltage VDRV for landing detection and removal detection from the power supply voltage control unit 14 during the period of intermittent power transmission for landing detection and removal detection. The drivers DR1 and DR2 are supplied.

  Here, the power supply voltage for landing detection and removal detection is a voltage corresponding to the voltage level on the high potential side in the signal waveform of the primary coil driving voltage in FIGS. 12, 13, and 14 described above. The landing detection power supply voltage and the removal detection power supply voltage may be the same voltage or different voltages. For example, the power supply voltage for removal detection may be set to a voltage higher than the power supply voltage for landing detection. By setting the power supply voltage for removal detection to a high voltage, it is possible to suppress the occurrence of a situation in which the electronic device 510 is erroneously detected as being removed even though the electronic device 510 is not actually removed.

  Alternatively, the control unit 24 may supply a variable voltage from the power supply voltage control unit 14 to the power transmission drivers DR1 and DR2 as a power supply voltage for landing detection or removal detection.

  By preparing two types of power supply voltages such as 6V and 9V as power supply voltages for landing detection, landing detection can be performed in a wide range. For example, if the power supply voltage of a high voltage (for example, 9V) is suddenly applied when the coils of L1 and L2 are close, the withstand voltage on the power receiving side (secondary side) may be exceeded, which may cause problems. On the other hand, when the power supply voltage is low (for example, 6 V), there is a problem that appropriate landing detection or the like cannot be realized when the distance between the coils L1 and L2 is long.

  In this respect, the above-described problem can be solved by variably controlling the power supply voltage for landing detection or removal detection. For example, in intermittent power transmission for landing detection or removal detection, after driving with a voltage of, for example, 6V in the first half period of the power transmission period (TL2, TR2), 9V ( (TL2 = 50 msec). This allows a wider range of landings. In this case, control for gradually increasing the power supply voltage for landing detection or removal detection, such as 6V to 9V, may be performed.

  FIG. 15A shows an example in which the distance between the L1 and L2 coils is reduced. In this case, after landing detection is performed with the power supply voltage VDRV of 9 V, control is performed such that the power supply voltage VDRV gradually decreases as the distance between the coils approaches. That is, the power supply voltage control unit 14 performs control to lower the power supply voltage VDRV supplied to the power transmission drivers DR1 and DR2 under the control of the control unit 24. That is, the power supply voltage VDRV is controlled so that the rectified voltage VCC that is the output voltage of the power receiving unit 52 is constant. As a result, even when the distance between the coils L1 and L2 approaches, power control is performed such that the received power of the power receiving device 40 is constant, and optimal and stable power control can be realized.

  Next, FIG. 15B shows an example in which the distance between the coils L1 and L2 is increased. In this case, control is performed in which the power supply voltage VDRV gradually increases as the distance between the coils increases. That is, the power supply voltage control unit 14 performs control to increase the power supply voltage VDRV supplied to the power transmission drivers DR1 and DR2 under the control of the control unit 24. That is, the power supply voltage VDRV is controlled so that the rectified voltage VCC that is the output voltage of the power receiving unit 52 is constant. As a result, even when the distance between the coils L1 and L2 is increased, power control is performed such that the received power of the power receiving device 40 is constant, and optimal and stable power control can be realized.

7). Communication Method Next, a communication method using load modulation will be described with reference to FIG. For example, in the present embodiment, when the power receiving device 40 performs load modulation, the above-described transmission power setting information is transmitted to the control device 20 of the power transmission device 10, and the control device 20 of the power transmission device 10 transmits the transmission power setting information. Receive.

  In this case, as shown in FIG. 16, on the power transmission side, the power transmission drivers DR1 and DR2 operate based on the power supply voltage VDRV supplied from the power supply voltage control unit 14 to drive the primary coil L1.

  On the other hand, on the power receiving side (secondary side), the rectifier circuit 53 of the power receiving unit 52 rectifies the coil end voltage of the secondary coil L2, and the rectified voltage VCC is output to the node NVC. The primary coil L1 and the capacitor CA1 constitute a power transmission side resonance circuit, and the secondary coil L2 and the capacitor CA2 constitute a power reception side resonance circuit.

  On the power receiving side, by turning on / off the switch element SW of the load modulation unit 56, the current ID2 of the current source IS is intermittently passed from the node NVC to the GND side, and the load state on the power receiving side (the potential on the power receiving side) Fluctuate.

  On the power transmission side, the current ID1 flowing through the sense resistor RCS provided in the power supply line varies due to the variation of the load state on the power receiving side due to the load modulation. For example, a sense resistor RCS for detecting a current flowing through the power source is provided between the power source on the power transmission side (for example, a power source device such as the power adapter 502 in FIG. 1A) and the power source voltage control unit 14. The power supply voltage control unit 14 is supplied with a power supply voltage from the power supply via the sense resistor RCS. The current ID1 flowing from the power source to the sense resistor RCS fluctuates due to fluctuations in the load state on the power receiving side due to load modulation, and the communication unit 30 detects this current fluctuation. And the communication part 30 performs the detection process of the communication data transmitted by load modulation based on a detection result.

  FIG. 17 is a diagram illustrating a communication configuration on the power receiving side. The power receiving unit 52 extracts a rectangular wave signal corresponding to the power transmission signal waveform by shaping the coil end signal of the secondary coil L <b> 2, and supplies it to the communication data generation unit 43. The communication data generation unit 43 is provided in the control unit 54 and includes a power transmission frequency measurement unit 44. The power transmission frequency measuring unit 44 measures the power transmission frequency by counting the period of the rectangular wave signal corresponding to the power transmission signal waveform using the clock signal generated by the oscillation circuit 45. The communication data generation unit 43 generates a control signal CSW for transmitting communication data based on the measured power transmission frequency, and outputs the control signal CSW to the load modulation unit 56. Then, for example, on / off control of the switch element SW is performed by the control signal CSW, and the load modulation unit 56 performs load modulation corresponding to the communication data.

  The load modulation unit 56 performs load modulation by changing the load state on the power receiving side (load due to load modulation) such as a first load state and a second load state. The first load state is a state where, for example, the switch element SW is turned on, and the load state on the power receiving side (load modulation load) is a high load (impedance is small). The second load state is a state in which, for example, the switch element SW is turned off, and the load state (load modulation load) on the power receiving side is a low load (impedance is large).

  For example, the first load state is made to correspond to the logical level “1” (first logical level) of the communication data, and the second load state is changed to the logical level “0” (second logical level of the communication data). ), Communication data is transmitted from the power receiving side to the power transmitting side. That is, when the logic level of the bit of communication data is “1”, the switch element SW is turned on, and when the logic level of the bit of communication data is “0”, the switch element SW is turned off. Thus, communication data having a predetermined number of bits is transmitted.

  Also, as shown in FIG. 18, the logical level “1” (data 1) and the logical level “0” (data 0) of each bit of communication data are transmitted from the power receiving side using the load modulation pattern, You may detect in the power transmission side. In this case, for the first logical level “1” of the communication data to be transmitted to the power transmission apparatus 10, the power receiving side load modulation unit 56 performs load modulation in which the load modulation pattern becomes the first pattern PT1. On the other hand, for the second logic level “0” of the communication data, load modulation is performed such that the load modulation pattern becomes a second pattern PT2 different from the first pattern PT1.

  Then, when the load modulation pattern is the first pattern PT1, the power transmission side communication unit 30 (demodulation unit) determines that the communication data is the first logic level “1”. On the other hand, when the load modulation pattern is the second pattern PT2 different from the first pattern PT1, it is determined that the communication data is the second logic level “0”.

  Here, the load modulation pattern is a pattern configured by a first load state and a second load state. The first load state is a state in which the load on the power receiving side by the load modulation unit 56 becomes a high load, for example. Specifically, in FIG. 18, the first load state period TM1 is a period in which the switch element SW of the load modulation unit 56 is turned on and the current of the current source IS flows from the node NVC to the GND side. This is a period corresponding to the H level (bit = 1) of the first and second patterns PT1, PT2.

  On the other hand, the second load state is a state in which the load on the power receiving side by the load modulation unit 56 becomes a low load, for example. Specifically, in FIG. 18, the second load state period TM2 is a period in which the switch element SW of the load modulation unit 56 is turned off, and the L level (bit = bit = 1) of the first and second patterns PT1 and PT2. 0).

  In FIG. 18, the first pattern PT1 is a pattern in which the width of the period TM1 in the first load state is longer than that of the second pattern PT2. Thus, it is determined that the first pattern PT1 having the width of the period TM1 in the first load state is longer than that of the second pattern PT2 is the logic level “1”. On the other hand, it is determined that the second pattern PT2 in which the width of the period TM1 in the first load state is shorter than the first pattern PT1 is the logic level “0”.

  As shown in FIG. 18, the first pattern PT1 is a pattern corresponding to, for example, the bit pattern (1110). The second pattern PT2 is a pattern corresponding to the bit pattern (1010), for example. In these bit patterns, bit = 1 corresponds to a state in which the switch element SW of the load modulation unit 56 is turned on, and bit = 0 corresponds to a state in which the switch element SW of the load modulation unit 56 is turned off.

  This makes it possible to properly detect communication data even in a situation where there is a lot of noise.

  Next, FIG. 19A and FIG. 19B show examples of the format of communication data used in the present embodiment.

  In FIG. 19A, communication data is composed of 64 bits, and one packet is composed of 64 bits. The first 16 bits are 0000h. For example, when load modulation on the power receiving side is detected and the power transmission side starts normal power transmission (or intermittent power transmission), until the current detection circuit of the communication unit 30 operates and communication data can be properly detected. A certain amount of time is required. Therefore, 0000h, which is dummy (empty) data, is set in the first 16 bits. The power transmission side performs various processes necessary for bit synchronization, for example, in the communication period of 0000h of the first 16 bits.

  In the next second 16 bits, data code and rectified voltage (VCC) information are set. As shown in FIG. 19B, the data code is a code for specifying data communicated by the next third 16 bits. The rectified voltage (VCC) is used as transmission power setting information for the power transmission device 10 as described above.

  In the third 16 bits, information such as temperature, battery voltage, battery current, status flag, number of cycles, IC number, charge execution / off start, or ID is set according to the setting in the data code. The temperature is, for example, a battery temperature. The battery voltage and the battery current are information indicating the charging state of the battery 90. The status flag is information indicating the status on the power receiving side such as temperature error (high temperature abnormality, low temperature abnormality), battery error (battery voltage of 1.0 V or less), overvoltage error, timer error, full charge (normal end), and the like. . The number of cycles (cycle time) is information representing the number of times of charging. The IC number is a number for specifying the IC of the control device. The charge execution flag (CGO) is a flag indicating that the authenticated power transmission side is appropriate and charging is executed based on the transmitted power from the power transmission side. CRC information is set in the fourth 16 bits.

  Note that the communication method of the present embodiment is not limited to the method described in FIGS. 18 to 19B and the like, and various modifications can be made. For example, in FIG. 18, the logical level “1” is associated with the first pattern PT1, and the logical level “0” is associated with the second pattern PT2, but this association may be reversed. Also, the first and second patterns PT1 and PT2 in FIG. 18 are examples of load modulation patterns, and the load modulation pattern of the present embodiment is not limited to this, and various modifications can be made. For example, in FIG. 18, the first and second patterns PT1 and PT2 are set to the same length, but may be set to different lengths. In FIG. 18, the first pattern PT1 of the bit pattern (1110) and the second pattern PT2 of the bit pattern (1010) are used, but the first and second patterns of bit patterns different from these are used. PT1 and PT2 may be adopted. For example, the first and second patterns PT1 and PT2 may be patterns having different lengths of at least the first load state period TM1 (or the second load state period TM2). The pattern can be adopted. Further, the format of communication data and communication processing are not limited to the method described in this embodiment, and various modifications can be made.

  Although the present embodiment has been described in detail as described above, it will be easily understood by those skilled in the art that many modifications can be made without departing from the novel matters and effects of the present invention. Accordingly, all such modifications are intended to be included in the scope of the present invention. For example, a term described at least once together with a different term having a broader meaning or the same meaning in the specification or the drawings can be replaced with the different term in any part of the specification or the drawings. In addition, the configurations and operations of the control device, the power transmission device, and the electronic device are not limited to those described in this embodiment, and various modifications can be made.

DESCRIPTION OF SYMBOLS 10 ... Power transmission apparatus, 12 ... Power transmission part, 14 ... Power supply voltage control part, 16 ... Notification part, 20 ... Control apparatus,
22 ... Driver control circuit, 23 ... Storage unit, 24 ... Control unit, 26 ... Power supply voltage setting unit,
30 ... communication unit, 37 ... clock generation circuit, 38 ... oscillation circuit, 40 ... power receiving device,
42 ... power supply switch, 43 ... communication data generation unit, 44 ... power transmission frequency measurement unit,
45 ... Oscillator circuit, 46 ... Communication unit, 48 ... Storage unit, 50 ... Control device, 52 ... Power receiving unit,
53 ... Rectifier circuit, 54 ... Control unit, 56 ... Load modulation unit, 57 ... Power supply unit, 58 ... Charging unit,
59 ... CC charging circuit, 60 ... discharge section, 61 ... charge pump circuit,
62 ... Nonvolatile memory, 64 ... Detection unit, 65 ... A / D conversion circuit, 80 ... Load,
90 ... Battery, 100 ... Power supply target, 231 ... Determination parameter setting register,
241 ... Data comparison circuit, 242 ... Change amount setting circuit, 243 ... Change time setting circuit,
244 ... Data setting circuit, 500 ... Charger, 502 ... Power adapter, 510 ... Electronic device,
514 ... Switch part

Claims (11)

A control device used in a power transmission device that transmits power to a power receiving device by contactless power transmission,
A control unit that controls a power transmission unit that transmits power to the power receiving device;
A communication unit that performs communication processing for receiving communication data transmitted by the power receiving device;
Including
The controller is
Based on the communication data, obtain information on the transmission power setting value for setting the magnitude of the power transmitted from the power transmission device to the power reception device, the larger the difference between the transmission power setting value and the target value, A control device that controls transmission power of the power transmission unit with a large power width. In claim 1,
The controller is
Based on the communication data, information on the output voltage of the power receiving unit of the power receiving device is acquired as information on the transmission power setting value, and the difference between the target voltage that is the target value and the output voltage of the power receiving unit is The control apparatus characterized by controlling the transmitted power of the power transmission unit with a larger power width as the value increases. In claim 1 or 2,
The power transmission unit
Including power transmission drivers,
The controller is
A control device, wherein the transmission power is controlled by changing a drive voltage supplied as a power source to the power transmission driver. In any one of Claims 1 thru | or 3,
The controller is
When the difference value between the transmission power setting value and the target value is larger than a first predetermined value, the transmission power is controlled with a first power width,
A second power width smaller than the first power width when the difference value between the transmission power set value and the target value is less than the first predetermined value and greater than a second predetermined value; The control apparatus characterized by controlling the transmitted power. In claim 4,
The controller is
When the difference value between the transmission power set value and the target value is less than the first predetermined value and larger than the second predetermined value, the second power width is equal to the second power width in the first period. Changing the transmitted power,
When the difference value between the transmission power setting value and the target value is less than or equal to the second predetermined value, in a second period longer than the first period, A control device that changes the transmitted power. In claim 4 or 5,
A control apparatus comprising: a storage unit configured to store at least the first power width variably. In any one of Claims 1 thru | or 6.
The controller is
If the first target value is greater than the second target value,
When the transmission power set value is larger than the first target value, the transmission power is reduced,
When the transmission power set value is smaller than the second target value, increase the transmission power,
The control device, wherein the transmission power is not changed when the transmission power set value is not less than the first target value and not more than the second target value. A control device used in a power transmission device that transmits power to a power receiving device by contactless power transmission,
A control unit that controls a power transmission unit that transmits power to the power receiving device;
A communication unit that performs communication processing for receiving communication data transmitted by the power receiving device;
Including
The controller is
Information on the transmission power setting value is acquired based on the communication data, and when the difference value between the transmission power setting value and the target value is larger than a predetermined value, the transmission power is transmitted with a predetermined power width in the first period. Change
When the difference value between the transmission power setting value and the target value is less than or equal to the predetermined value, the transmission power is changed with the predetermined power width in a second period longer than the first period. A control device characterized in that A control device used in a power transmission device that transmits power to a power receiving device by contactless power transmission,
A control unit that controls a power transmission unit that transmits power to the power receiving device;
A communication unit for processing communication data received from the power receiving device;
Including
The controller is
Based on the communication data, the output voltage of the power receiving unit of the power receiving device is compared with the target voltage that is the target value of the output voltage,
When the difference value between the output voltage and the target voltage is the first potential difference, the transmission power is changed with the first power width,
When the difference value between the output voltage and the target voltage is a second potential difference that is larger than the first potential difference, the transmission power is changed with a second power width that is larger than the first power width. A control device characterized in that   A power transmission device comprising the control device according to claim 1.   An electronic apparatus comprising the control device according to claim 1.