JP2017050939A - Electronic apparatus, control method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable stable power reception without repetition of an excessive state and a shortage state of reception power.SOLUTION: When the reception power repeats in a power excessive region and a power shortage region, a power maintenance flag is set to "1" in order to obtain stable power. Then, if reception power is maintained and the number of power maintenance times is repeated for 10 times, it is determined that power maintenance is to be canceled to fall into a power excessive region, to cause a power transmission device to reduce transmission power, so that reception power falls within a power proper region to enable stable power reception.SELECTED DRAWING: Figure 13

Description

  The present invention relates to an electronic device capable of receiving stable power from a power transmission device wirelessly and a control method thereof.

  There is known a wireless power transmission system including a power transmission device that wirelessly transmits power and a power reception device that receives power transmitted from the power transmission device. Patent Document 1 describes a wireless power transmission system in which load state information indicating a load state of a power receiving device is transmitted from the power receiving device to the power transmitting device, and the power transmitting device controls the power transmission output using the load state information.

JP 2007-336787 A

  However, in the system described in Patent Literature 1, even if the power receiving apparatus transmits load state information to the power transmitting apparatus and the power transmitting apparatus controls the power transmission output, the received power of the power receiving apparatus may not be stable. For example, even if the power receiving device transmits state information to the power transmitting device through communication, if the output adjustment of the power transmitting device cannot be made in detail and is rough, the power to be received may be excessive or insufficient. Repeatedly, it may not be stable.

  Therefore, an object of the present invention is to make it possible to receive stable power that does not repeatedly cause the received power to be in an excessive state or an insufficient state.

  In order to achieve the above object, an electronic device according to the present invention includes a power receiving unit that wirelessly receives power from a power transmission device, and whether the power received by the power receiving unit is insufficient, excessive, or appropriate. A detecting means for detecting, a generating means for generating, as state information, information indicating that the power received by the power receiving means is insufficient, excessive or appropriate based on a detection result of the detecting means; and the generating means Communication means for transmitting the generated state information to the power transmission device, and when the detection means alternately detects a shortage and an excess for a predetermined number of times, the generation means is received by the power reception means. It is characterized by changing to the control which produces | generates the status information which shows that the electric power was appropriate.

  ADVANTAGE OF THE INVENTION According to this invention, the stable electric power which does not repeat that receiving electric power becomes an excessive state and an insufficient state can be received.

It is a figure for demonstrating an example of a structure of the wireless power transmission system in Embodiment 1. FIG. It is a block diagram for demonstrating the some component which the power transmission apparatus 100 has, and the some component which an electronic device has. 5 is a flowchart for explaining an example of processing performed in power transmission device 100. 6 is a flowchart for explaining an example of processing performed in electronic device 200. 5 is a flowchart for explaining an example of received power determination processing performed in S412 of FIG. 6 is a flowchart for explaining an example of a first determination process performed in S504 of FIG. 6 is a flowchart for explaining an example of a second determination process performed in S507 of FIG. 6 is a flowchart for explaining an example of a third determination process performed in S510 of FIG. 5. 6 is a flowchart for explaining an example of a fourth determination process performed in S513 of FIG. 6 is a flowchart for describing an example of a fifth determination process performed in S515 of FIG. 5. 6 is a flowchart for explaining an example of a release determination process performed in S516 of FIG. It is a figure which shows an example of the time change of the voltage output from the rectification smoothing part. It is a figure which shows an example of the time change of the voltage output from the rectification smoothing part 203 until it changes from an unstable state to a stable state.

Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following embodiments.
[Embodiment 1]
FIG. 1 is a diagram for explaining an example of the configuration of the wireless power transmission system according to the first embodiment.
As illustrated in FIG. 1, the wireless power transmission system includes a power transmission device 100 and an electronic device 200. The power transmission device 100 is configured to be able to operate as a power supply device, and the electronic device 200 is configured to be able to operate as a power receiving device. In the wireless power transmission system according to the first embodiment, when the electronic device 200 is placed on the power transmission device 100, the power transmission device 100 can communicate with the electronic device 200 wirelessly or transmit power to the electronic device 200 wirelessly. You can also

  When the distance between the power transmission device 100 and the electronic device 200 is within a predetermined range, the electronic device 200 receives the power transmitted from the power transmission device 100 wirelessly. Furthermore, the electronic device 200 charges the secondary battery connected to the electronic device 200 with the power received from the power transmission device 100.

  When the distance between the power transmission device 100 and the electronic device 200 does not exist within a predetermined range, the electronic device 200 cannot communicate with the power transmission device 100. Note that the predetermined range is a range in which the electronic device 200 can perform communication using the power supplied from the power transmission device 100.

  The power transmission device 100 may be capable of supplying power to the plurality of electronic devices 200 simultaneously or selectively wirelessly. When the secondary battery is not connected to the electronic device 200, the electronic device 200 may be an electronic device that operates with power supplied from the power transmission device 100. The electronic device 200 may be a device that operates as an imaging device or a mobile phone, for example. A smartphone, a digital camera, and a mobile phone with a camera are examples of the electronic device 200. The electronic device 200 may be, for example, a device that operates as a playback device that plays back audio data or image data. The electronic device 200 may be a moving device such as a car, for example.

FIG. 2 is a block diagram for explaining a plurality of components included in the power transmission device 100 and a plurality of components included in the electronic device 200.
As illustrated in FIG. 2, the power transmission device 100 includes an oscillator 101, a power transmission circuit 102, a matching circuit 103, a communication control unit 104, a CPU (Central Processing Unit) 105, a first memory 106, 2 memory 107. Furthermore, the power transmission apparatus 100 includes an antenna 108, a timer 109, an instruction input unit 110, a conversion unit 111, a display unit 112, an LED 113, and a reflected power detection circuit 114.

  The oscillator 101 is driven by the power supplied from the AC power supply via the conversion unit 111 and oscillates a frequency used for controlling the power transmission circuit 102. The oscillator 101 uses a crystal resonator or the like.

  The power transmission circuit 102 generates power to be supplied to the electronic device 200 via the antenna 108 according to the power supplied from the conversion unit 111 and the frequency oscillated by the oscillator 101. The power transmission circuit 102 has an FET or the like inside, and controls the current flowing between the source and drain terminals by the gate voltage of the internal FET in accordance with the frequency oscillated by the oscillator 101, thereby Power to be supplied to 200 is generated. Note that the power generated by the power transmission circuit 102 is supplied to the matching circuit 103. The power transmission circuit 102 can also stop the power from the FET by controlling the gate voltage of the internal FET.

  The power generated by the power transmission circuit 102 includes communication power and transmission power. The communication power is communication power for supplying a request for the power transmission apparatus 100 to control the electronic device 200 to the electronic device 200. The transmitted power is power that is supplied to the electronic device 200 when the power transmission device 100 transmits power to the electronic device 200. For example, the communication power is 0.1 W to 1 W or less, and the transmitted power is 1 W to 10 W. While the communication power is set to be a constant power, the magnitude of the transmission power can be changed by controlling the power transmission circuit 102. Note that the communication power is assumed to be equal to or lower than the transmission power, and the transmission using the communication power is defined as the first transmission, and the transmission using the transmission power is defined as the second transmission.

  In the first embodiment, when the power transmission device 100 supplies communication power to the electronic device 200, the power transmission device 100 can transmit a request to the electronic device 200 via the antenna 108. However, when the power transmission device 100 supplies transmission power to the electronic device 200, the power transmission device 100 cannot transmit a request to the electronic device 200 via the antenna 108.

  The CPU 105 controls the power transmission circuit 102 so that the power to be supplied to the electronic device 200 is switched to any one of communication power, transmission power, and power stop.

The matching circuit 103 is also a resonance circuit that resonates at the resonance frequency f represented by the following formula (1) by the antenna 108 and the capacitor capacity in accordance with the frequency oscillated by the oscillator 101. Hereinafter, a frequency at which the power transmission device 100 and a device that is a target of power transmission of the power transmission device 100 perform resonance is referred to as a “resonance frequency f”. The following equation (1) represents the resonance frequency f, L represents the inductance of the antenna 108, and C represents the capacitance of the matching circuit 103.
f = 1 / {2π (LC) ^1/2 } (1)

  The resonance frequency f may be a commercial frequency of 50/60 Hz, may be 10 to several hundred kHz, or may be a frequency around 10 MHz. L may include not only the inductance of the antenna 108 but also a parasitic inductance such as a circuit. Similarly, C may include not only the capacitance of the matching circuit 103 but also a parasitic capacitance such as a circuit. In a state where the frequency oscillated by the oscillator 101 is controlled to the resonance frequency f, the power generated by the power transmission circuit 102 is supplied to the antenna 108 via the matching circuit 103.

  The communication control unit 104 modulates the power generated by the power transmission circuit 102 according to a predetermined protocol in order to transmit a request for controlling the electronic device 200 to the electronic device 200. The predetermined protocol is a communication protocol based on ISO / IEC 18092 standard such as RFID (Radio Frequency IDentification). The predetermined protocol may be a communication protocol compliant with the NFC (Near Field Communication) standard. The power generated by the power transmission circuit 102 is converted into an analog signal by the communication control unit 104 as a request for communication with the electronic device 200 and transmitted to the electronic device 200 via the antenna 108.

  The pulse signal transmitted to the electronic device 200 is detected by the electronic device 200 as bit data including information “1” and information “0”. The request includes identification information for identifying the destination, a request code indicating an operation instructed by the request, and the like. The CPU 105 can transmit the request only to the electronic device 200 by controlling the communication control unit 104 so as to change the identification information included in the request. Furthermore, the CPU 105 can also transmit the request to the electronic device 200 and devices other than the electronic device 200 by controlling the communication control unit 104 so as to change the identification information included in the request.

  The communication control unit 104 converts the power generated by the power transmission circuit 102 into a pulse signal by ASK (Amplitude Shift Keying) modulation using amplitude displacement. ASK modulation is modulation using amplitude displacement, and is used for communication between an IC card and a card reader that communicates wirelessly with the IC card.

  The communication control unit 104 changes the amplitude of the power generated by the power transmission circuit 102 by switching the analog multiplier and the load resistance included in the communication control unit 104. As a result, the communication control unit 104 changes the power generated by the power transmission circuit 102 to a pulse signal. The pulse signal changed by the communication control unit 104 is supplied to the antenna 108 and transmitted to the electronic device 200 as a request. Further, the communication control unit 104 includes an encoding circuit using a predetermined encoding method.

The communication control unit 104 decodes a response from the electronic device 200 to a request transmitted to the electronic device 200 and information transmitted from the electronic device 200 in accordance with a change in the current flowing through the antenna 108 detected by the matching circuit 103. Demodulated by the circuit. Accordingly, the communication control unit 104 can receive a response to the request transmitted to the electronic device 200 by the load modulation method and information transmitted from the electronic device 200 from the electronic device 200. The communication control unit 104 transmits a request to the electronic device 200 in response to an instruction from the CPU 105. Further, when receiving a response and information from the electronic device 200, the communication control unit 104 demodulates the received response and information and supplies the demodulated response and information to the CPU 105.
The communication control unit 104 holds a register for controlling communication, and can be controlled by the CPU 105 to adjust transmission / reception sensitivity during communication.

  CPU105 controls each component of the power transmission apparatus 100 with the electric power supplied via the conversion part 111 from AC power supply, when AC power supply and the power transmission apparatus 100 are connected. The CPU 105 can control each component of the power transmission apparatus 100 by executing one or more programs stored in the first memory 106. The CPU 105 controls the power supplied to the electronic device 200 by controlling the power transmission circuit 102. The CPU 105 transmits a request to the electronic device 200 by controlling the communication control unit 104.

The first memory 106 is a memory that stores one or a plurality of programs for controlling each component of the power transmission device 100 and information regarding the operation and state of each component of the power transmission device 100. The first memory 106 also stores image data such as menu information displayed on the display unit 112.
The second memory 107 is a rewritable memory. The second memory 107 can operate as a work memory for the CPU 105. Therefore, the second memory 107 can store various information, data, values, parameters, and programs used by the CPU 105.

  The antenna 108 is an antenna for outputting the power generated by the power transmission circuit 102 to the outside. The power transmission apparatus 100 supplies power to the electronic device 200 via the antenna 108 and transmits a request to the electronic device 200 via the antenna 108. The power transmission apparatus 100 receives a request from the electronic device 200 via the antenna 108, receives a response corresponding to the request transmitted to the electronic device 200, and receives information transmitted from the electronic device 200. You can also

  The timer 109 measures the current time, time related to operations and processes performed by each component, and the like. A threshold for the time measured by the timer 109 is recorded in the first memory 106 in advance.

  The instruction input unit 110 provides a user interface for inputting a user instruction to the power transmission apparatus 100. The instruction input unit 110 includes a power button, a mode switching button for switching the operation mode of the power transmission device 100, and the like, and each button includes a switch, a touch panel, and the like. CPU 105 controls power transmission device 100 in accordance with a user instruction input via instruction input unit 110. Note that the instruction input unit 110 may control the power transmission device 100 in accordance with an instruction received from the remote controller.

When the AC power source and the power transmission device 100 are connected, the conversion unit 111 converts AC power supplied from the AC power source into DC power, and supplies the converted DC power to the entire power transmission device 100.
The display unit 112 is a display unit that displays display contents generated by the CPU 105. For example, the display unit 112 includes a liquid crystal, an organic EL, and the like and a control unit that controls them.
The LED 113 is configured by a light emitting diode, and is controlled by the CPU 105 to control whether the communication control unit 104 performs communication or whether the power transmission circuit 102 is controlled to output power. Emits light to inform the user.

  The reflected power detection circuit 114 detects information indicating the amplitude voltage V1 of the traveling wave of power output from the antenna 108 and information indicating the amplitude voltage V2 of the reflected wave of power output from the antenna 108. Information indicating the amplitude voltage V1 and information indicating the amplitude voltage V2 detected by the reflected power detection circuit 114 are supplied to the CPU 105 as detection results. The CPU 105 records information indicating the amplitude voltage V <b> 1 and information indicating the amplitude voltage V <b> 2 supplied from the reflected power detection circuit 114 in the second memory 107. The CPU 105 obtains the voltage reflection coefficient ρ from the amplitude voltage V1 of the traveling wave and the amplitude voltage V2 of the reflected wave. Furthermore, the CPU 105 calculates a voltage standing wave ratio VSWR (Voltage Standing Wave Ratio) based on the voltage reflection coefficient ρ.

The voltage standing wave ratio VSWR is a value indicating the relationship between the traveling wave of power input to the antenna 108 and the reflected wave of power reflected from the antenna 108. The closer the value of the voltage standing wave ratio VSWR is to 1, the smaller the reflected power, the less the loss of power supplied from the power transmission apparatus 100 to the external electronic device, and the better the efficiency.
The following equation (2) represents the voltage reflection coefficient ρ, and the following equation (3) represents the voltage standing wave ratio VSWR.
ρ = V2 / V1 (2)
VSWR = (1 + ρ) / (1-ρ) (3)

  Hereinafter, the voltage standing wave ratio VSWR is referred to as “VSWR”. The CPU 105 uses the calculated VSWR to determine whether there is a foreign object in the vicinity of the power transmission apparatus 100 using the change in the VSWR when the foreign object exists in the vicinity.

  As shown in FIG. 2, the electronic device 200 includes an antenna 201, a matching unit 202, a rectifying / smoothing unit 203, a communication control unit 204, a memory 204 a, a CPU 205 (Central Processing Unit), and a first memory 206. And a second memory 207. Furthermore, the electronic device 200 includes a power control unit 208, a charge control unit 209, a secondary battery 210, a timer 211, an instruction input unit 212, and a display unit 213.

  The antenna 201 is an antenna for receiving power supplied from the power transmission device 100. The electronic device 200 receives power from the power transmission device 100 via the antenna 201 and receives a request. The electronic device 200 transmits a request for controlling the power transmission device 100 via the antenna 201, a response corresponding to the request received from the power transmission device 100, and predetermined information.

  The matching unit 202 is a circuit for performing impedance matching between the antenna 201 and the rectifying / smoothing unit 203 and the communication control unit 204 when the antenna 201 resonates at the same frequency as the resonance frequency f of the power transmission device 100. Similar to the matching circuit 103, the matching unit 202 includes a capacitor, a coil, a resistor, and the like. The matching unit 202 supplies the power received by the antenna 201 to the rectifying / smoothing unit 203. The matching unit 202 supplies a part of the power received by the antenna 201 to the communication control unit 204 as a request with an AC waveform.

  The rectifying / smoothing unit 203 generates DC power from the power received by the antenna 201. Further, the rectifying / smoothing unit 203 supplies the generated DC power to the power supply control unit 208. Note that the rectifying / smoothing unit 203 includes a rectifying diode and generates DC power by one of full-wave rectification and half-wave rectification.

  The communication control unit 204 analyzes the request supplied from the matching unit 202 according to the power transmission device 100 and a predetermined communication protocol, determines the analysis result itself according to the type of request, and passes through the antenna 201. Send a response to the request. The communication control unit 204 accesses the memory 204a according to the type of request. For example, if the request is a read request, the communication control unit 204 reads data from the memory 204 a and transmits the data to the power transmission apparatus 100. If the request is a write request, the communication control unit 204 receives data after the request and writes the received data to the memory 204a. Note that the communication control unit 204 can notify the CPU 205 that the request has been received, and can also notify the CPU 205 that the data in the memory 204a has been read / written.

  The communication control unit 204 controls the load such as a resistance included in the communication control unit 204 to vary ON / OFF in order to transmit a response to the request and predetermined information to the power transmission apparatus 100, and performs communication as a load modulation signal. Do. When the load included in the communication control unit 204 changes, the current flowing through the antenna 108 changes. Thereby, the power transmission apparatus 100 receives a request, a response to the request, and predetermined information transmitted from the electronic device 200 by detecting a change in the current flowing through the antenna 108.

  The CPU 205 determines which request is the request received by the communication control unit 204 according to the analysis result supplied from the communication control unit 204. Then, the electronic device 200 is controlled to perform the process and operation specified by the request code corresponding to the received request.

  The memory 204 a is a nonvolatile memory included in the communication control unit 204 and is accessed from the power transmission device 100 and the CPU 205. When the power transmission device 100 and the CPU 205 are accessed at the same time, access from the other is denied until one access is completed by exclusive control.

  The CPU 205 transmits a response to the request for device authentication from the power transmission apparatus 100 via the communication control unit 204, and transmits a response to the request for acquiring the status information via the communication control unit 204. The CPU 205 can control each component of the electronic device 200 by executing one or more programs stored in the first memory 206.

  The first memory 206 is a memory that stores one or more programs for controlling each component of the electronic device 200 and information regarding the operation and state of each component of the electronic device 200. The first memory 206 stores identification information and device information of the electronic device 200. The identification information of the electronic device 200 includes information indicating the ID of the electronic device 200. The device information of the electronic device 200 includes information indicating the manufacturer name, the device name, the date of manufacture, and the capability of the electronic device 200.

  The second memory 207 is a rewritable memory. The second memory 207 can operate as a work memory for the CPU 205. Therefore, the second memory 207 can store various information, data, values, parameters, and programs used by the CPU 205.

  The power supply control unit 208 includes a switching regulator, a linear regulator, and the like, and supplies DC power supplied from the rectifying and smoothing unit 203 to the charging control unit 209 and the entire electronic device 200. The power control unit 208 can stop the power supply to the charge control unit 209 under the control of the CPU 205. The power supply control unit 208 can also make the load impedance of the subsequent stage constant.

  When power is supplied from the power supply control unit 208, the charging control unit 209 charges the secondary battery 210 according to the supplied power. The charging control unit 209 periodically detects information related to charging of the secondary battery 210 connected to the electronic device 200 and supplies the information to the CPU 205. Information regarding charging of the secondary battery 210 is included in the state information, and the CPU 205 records state information indicating the battery state in the second memory 207.

  The status information includes information indicating whether or not the secondary battery 210 is fully charged, in addition to the remaining capacity information indicating the remaining capacity of the secondary battery 210. The state information includes information indicating the time that has elapsed since the charging control unit 209 started charging the secondary battery 210. The state information includes information indicating whether the charging control unit 209 is performing constant voltage charging or constant current charging on the secondary battery 210. The state information includes information indicating whether or not the charging control unit 209 is performing software charging control on the secondary battery 210. The state information includes information indicating whether or not the charging control unit 209 is performing trickle charging or quick charging on the secondary battery 210.

  The state information includes power information indicating power necessary for the electronic device 200 to charge the secondary battery 210 and information indicating whether or not the secondary battery 210 is above a predetermined temperature. . The state information includes information indicating how much battery capacity is necessary for operating the electronic device 200. The state information includes information indicating how much the battery capacity decreases when the power from the power transmission device 100 is stopped and discharged. The state information includes information regarding the consumption of the secondary battery 210 such as information indicating the number of times the secondary battery 210 has been charged. Further, the status information includes information indicating that the received power is insufficient, information indicating that the received power is excessive, information indicating that the power is appropriate, and information requesting power transmission stop (hereinafter referred to as “power transmission stoppage”). , Transmission stop request information).

  The secondary battery 210 is a rechargeable battery and can be detached from the electronic device 200. Secondary battery 210 includes, for example, a lithium ion battery. The secondary battery 210 can supply power to each component of the electronic device 200. The secondary battery 210 can supply power to each component of the electronic device 200 when power is not supplied via the power control unit 208. For example, in the case where the first power during communication is set low and output from the power transmission device 100 and in the case where the power supply from the power transmission device 100 stops, the secondary battery 210 to the electronic device 200 Electric power is supplied to each component.

  The timer 211 measures the time related to the current time and the operations and processes performed in each component. The threshold for the time measured by the timer 211 is recorded in advance in the first memory 206.

  The instruction input unit 212 provides a user interface for inputting a user instruction to the electronic device 200. The instruction input unit 212 includes a power button, a mode switching button for switching the operation mode of the electronic device 200, and the like, and each button includes a switch, a touch panel, and the like. The CPU 205 controls the electronic device 200 in accordance with a user instruction input via the instruction input unit 212. Note that the instruction input unit 212 may control the electronic device 200 in accordance with an instruction received from the remote controller.

  The display unit 213 includes a liquid crystal panel, an organic EL panel, and the like, and displays an operation screen, a captured image, and the like based on an instruction from the CPU 205. The display unit 213 may be configured in a movable shape such as a vari-angle. In this case, the position information of the display unit 213 is converted into digital information and notified to the CPU 205.

  Note that the antenna 108 of the power transmission apparatus 100 and the antenna 201 of the electronic device 200 may be a helical antenna, a loop antenna, or a planar antenna such as a meander line antenna.

  In the first embodiment, the processing performed by the power transmission device 100 can be applied to a system in which the power transmission device 100 supplies power to the electronic device 200 wirelessly by magnetic field coupling or electric field coupling. Similarly, in the first embodiment, the processing performed by the electronic device 200 can be applied to a system in which the power transmission device 100 supplies power to the electronic device 200 wirelessly by magnetic field coupling or electric field coupling.

  The present invention can be applied to a system in which an electrode is provided in the power transmission device 100 as the antenna 108 and an electrode is provided in the electronic device 200 as the antenna 201 so that the power transmission device 100 supplies power to the electronic device 200 by electric field coupling. it can. It is assumed that the processing performed by the power transmission device 100 and the processing performed by the electronic device 200 can also be applied to a system in which the power transmission device 100 wirelessly supplies power to the electronic device 200 by electromagnetic induction.

  In the first embodiment and other embodiments, the power transmission device 100 wirelessly transmits power to the electronic device 200, and the electronic device 200 receives power from the power transmission device 100 wirelessly. However, “wireless” may be rephrased as “non-contact” or “non-contact”.

  FIG. 3 is a flowchart for explaining an example of processing performed in the power transmission device 100. Note that the processing described with reference to FIG. 3 is controlled by the CPU 105 in accordance with a program stored in the first memory 106 when the power transmission device 100 is in the ON state.

  In step S <b> 301, the CPU 105 periodically outputs communication power via the antenna 108 and detects the proximity of the object to the power transmission device 100. In the proximity detection of the object, first, the CPU 205 controls the communication control unit 104 to output a predetermined instruction from the antenna 108 by the first power transmission. When the CPU 105 receives a response from the object, the CPU 105 detects the proximity of the object. When the CPU 105 detects the proximity of the object, the process proceeds to S302.

  In S <b> 302, the CPU 105 transmits an instruction for authenticating whether the object detected in proximity in S <b> 301 is the electronic device 200 to the object.

  In step S <b> 303, the CPU 105 stands by until authentication information indicating that the electronic device 200 is received from the object. When the authentication information is received, the process proceeds to S304. Here, the CPU 205 may count the time using the timer 109, and if no response is received within a certain time, the CPU 205 may return to S302 and transmit the request instruction again. Furthermore, when the response does not come within a certain time, the processing of the power transmission device 100 may be terminated.

  In S <b> 304, the CPU 105 determines whether or not the object is the electronic device 200 by analyzing the authentication information received in S <b> 303. When the CPU 105 determines that the object is the electronic device 200, the process proceeds to S <b> 305, and when the CPU 105 determines that the target is not the electronic device 200, the process of the power transmission device 100 ends.

  In S <b> 305, the CPU 105 transmits an instruction for requesting state information to the electronic device 200. In step S <b> 306, the CPU 105 determines whether status information has been received from the electronic device 200.

  When the CPU 105 receives the status information from the electronic device 200, in S307, the CPU 105 determines whether power transmission is unnecessary based on the received status information. For example, the CPU 105 determines whether or not power transmission is necessary depending on whether or not the received state information includes full state information or power transmission stop request information. If it is determined that power transmission is necessary, the process proceeds to S309. If it is determined that power transmission is not necessary, the process proceeds to S308.

  In S308, the CPU 105 transmits a power transmission end instruction to end the power transmission process to the electronic device 200, and ends the process. If the power transmission device 100 is transmitting power, the output of transmitted power is stopped and the process is terminated.

  On the other hand, in S <b> 309, the CPU 105 determines whether or not it is the first power transmission process after detecting the electronic device 200. As a result of this determination, if it is the first power transmission process, the process proceeds to S310, and if not, the process proceeds to S314. Here, when the power transmission process is performed, the CPU 105 stores in the second memory 107 that the processes from S309 to S313 have been performed. In the process of S309, the CPU 105 determines whether or not it is the first power transmission process depending on whether or not this information is stored in the second memory 107.

In S <b> 310, the CPU 105 sets the output level of the second power transmission to an initial value using the power transmission circuit 102. The initial value is, for example, an output at a low level among output levels capable of power transmission such as 1 W.
In step S <b> 311, the CPU 105 controls the power transmission circuit 102 to perform second power transmission, and the power transmission device 100 outputs transmitted power from the antenna 108.

  In S312, the CPU 105 detects the value of the timer 109 and waits until the power transmission period reaches a predetermined period. Then, when the power transmission period is determined in advance, the process proceeds to S313. In step S <b> 313, the CPU 105 controls the power transmission circuit 102 to stop the output of the transmission power, and returns to step S <b> 305 in order to confirm the charging state of the electronic device 200 again.

  On the other hand, in S <b> 314, the CPU 105 determines whether to increase or decrease the transmission power from the previous power transmission from the state information received in S <b> 306. In this process, if the status information includes information indicating that the power of the electronic device 200 is insufficient, the CPU 105 determines that the transmitted power needs to be increased. Even when there is information requesting to increase the transmission power in the state information, the CPU 105 determines that the transmission power needs to be increased. On the other hand, when there is information indicating that the power of the electronic device 200 is excessive in the state information, the CPU 105 determines that the transmitted power needs to be reduced. The CPU 205 determines that the transmission power needs to be reduced even when there is information requesting to reduce the transmission power from the electronic device 200 in the state information. As a result of the determination in S314, the process proceeds to S315 if the transmission power is to be increased from the previous transmission, and to S316 if the transmission power is to be decreased. When the status information includes information indicating that the received power is appropriate or information requesting maintenance of the output value of the transmitted power, the process proceeds from S314 to S311.

In S315, the CPU 105 controls the power transmission circuit 102 to increase the transmission power from the previous time, and proceeds to S311 to perform power transmission.
On the other hand, in S316, the CPU 105 controls the power transmission circuit 102 to lower the transmission power from the previous time, and proceeds to S311 to perform power transmission.

  As described above, the power transmission device 100 determines whether it is necessary to increase or decrease the transmitted power from the previous state based on the state information from the electronic device 200, and performs power transmission by controlling the level of the transmitted power according to the determination result. .

  FIG. 4 is a flowchart for explaining an example of processing performed in the electronic device 200. Note that the processing described with reference to FIG. 4 is controlled by the CPU 205 in accordance with a program stored in the first memory 206 when the electronic device 200 is powered on.

  In step S <b> 401, the CPU 205 determines whether an authentication request instruction for requesting authentication information of the electronic device 200 has been received. When the CPU 205 receives an authentication request instruction from the power transmission apparatus 100, the process proceeds to S402.

In step S <b> 402, the CPU 205 transmits authentication information indicating the electronic device 200 to the power transmission apparatus 100 via the communication control unit 204.
In step S <b> 403, the CPU 205 determines whether a status information request instruction for requesting status information of the electronic device 200 has been received. When the CPU 205 receives a state information request instruction from the power transmission apparatus 100, the process proceeds to S404.

  In step S404, the CPU 205 generates state information including information indicating the charging state of the secondary battery 210 (including the remaining amount of the secondary battery 210) and information indicating the result of the received power determination process performed in step S412. . In step S <b> 405, the CPU 205 transmits the state information generated in step S <b> 404 to the power transmission apparatus 100 via the communication control unit 204.

  In step S <b> 406, the CPU 205 stands by until a power transmission end instruction is received from the power transmission device 100 for a certain period. Then, when waiting for a certain period and not receiving a power transmission end instruction from the power transmission apparatus 100, the process proceeds to S407. On the other hand, when the CPU 205 receives a power transmission end instruction from the power transmission device 100, the entire process of the electronic device 200 is terminated.

  As described above, in the power transmission device 100, the CPU 105 determines whether or not power transmission is necessary based on the state information transmitted by the electronic device 200 in step S405. Transmit (S307, S308). For example, when the state information received by the power transmission device 100 includes either information indicating full charge or power transmission stop request information from the electronic device 200, the power transmission device 100 determines that power transmission is unnecessary. .

  On the other hand, when determining that the power transmission is necessary, the power transmission apparatus 100 outputs the transmission power from the antenna 108 in the second power transmission. And the electronic device 200 receives the transmission power output from the power transmission apparatus 100 as DC power by using the antenna 201, the matching unit 202, and the rectifying / smoothing unit 203. Further, the power transmission control unit 208 controls the transmitted power to a predetermined voltage level, and the charging control unit 209 charges the secondary battery 210. The CPU 205 detects the start of power reception by detecting the output value from the rectifying / smoothing unit 203. When the start of power reception is detected, the CPU 205 activates the timer 211 to measure the power transmission period.

  As described above, the transmission power output from the power transmission device 100 is received, and the secondary battery 210 is charged by the charge control unit 209 without the intervention of the CPU 205. In step S407, the CPU 205 detects the state of charge. The state of charge includes the state of the remaining capacity of the secondary battery 210 and the state of the temperature of the secondary battery 210.

  In S408, the CPU 205 determines whether or not the secondary battery 210 is fully charged based on the charging state detected in S407. When the CPU 205 determines that the secondary battery 210 is not fully charged, the process proceeds to S409, and when it is determined that the secondary battery 210 is fully charged, the process proceeds to S410.

  In step S409, the CPU 205 determines whether the end of the power transmission period is closer to the count value of the timer 211. If the CPU 205 determines that the end of the power transmission period is near, the process proceeds to S411. If it is determined that the power transmission period is not close, the process returns to S407 again. Here, the case near the end of the power transmission period is, for example, about 0.1 seconds before the power transmission period of 30 seconds. The guideline of 0.1 second is a sufficient time for performing the processing of S411 described later.

On the other hand, in S410, information indicating that the battery is fully charged is stored in the second memory 207, and the process proceeds to S411.
In step S411, the CPU 205 detects a voltage output from the rectifying / smoothing unit 203. By detecting the voltage output from the rectifying / smoothing unit 203, the CPU 205 can determine whether the received power of the electronic device 200 is insufficient, excessive, or appropriate. The reason why the received power of the electronic device 200 is detected at the timing of S411 is that it is close to the end of the power transmission period and is the latest state as the power receiving state of the electronic device 200.

  In step S412, the CPU 205 performs a received power determination process for determining the received power of the electronic device 200. Details of the received power determination process will be described later with reference to FIG. When the received power determination process ends, the process returns to S403.

  In the first embodiment, it is assumed that power transmission and communication are performed in a time division manner, but the time division may not be performed. In that case, since the received power of the electronic device 200 does not disappear, the measurement start of the power transmission period cannot be determined from the output value of the rectifying and smoothing unit 203. Therefore, in this case, the power transmission period is counted after transmitting the state information in S405. In this way, the electronic device 200 can know the power transmission period (communication timing).

An example of the relationship between the voltage output from the rectifying and smoothing unit 203 and the received power of the electronic device 200 will be described with reference to FIG. FIG. 12 is a diagram illustrating an example of a time change of the voltage output from the rectifying / smoothing unit 203.
Whether the received power of the electronic device 200 exists in a region below the lower power limit region, a power shortage region, a power appropriate region, a power excess region, or a power upper limit region is determined by the voltage output from the rectifying and smoothing unit 203 by the CPU 205. Judge based on level.

When the voltage output from the rectifying / smoothing unit 203 is equal to or lower than the lower limit value, the CPU 205 determines that the received power of the electronic device 200 exists in a region below the lower power limit. The lower limit value is a minimum value in a voltage range in which the electronic device 200 can operate normally, and is 4 V, for example.
When the voltage output from the rectifying and smoothing unit 203 is greater than the lower limit value and equal to or less than the first threshold value, the CPU 205 determines that the received power of the electronic device 200 is in the power shortage region. The first threshold value is a certain value within a voltage range in which the electronic device 200 can operate efficiently, and is, for example, 5V.
When the voltage output from the rectifying / smoothing unit 203 is greater than the first threshold value and less than or equal to the second threshold value, the CPU 205 determines that the received power of the electronic device 200 is in the appropriate power range. The second threshold is a certain value within a voltage range in which the electronic device 200 can operate efficiently, and is, for example, 12V.
When the voltage output from the rectifying / smoothing unit 203 is greater than the second threshold value and equal to or lower than the upper limit value, the CPU 205 determines that the received power of the electronic device 200 exists in the excessive power region. The upper limit value is a maximum value in a voltage range in which the electronic device 200 can operate normally, and is, for example, 14.5V. When it is less than or equal to the upper limit value, it is possible to eliminate the consumption of extra power.
When the voltage output from the rectifying / smoothing unit 203 is larger than the upper limit value, the CPU 205 determines that the received power of the electronic device 200 is in the region exceeding the power upper limit.

  FIG. 5 is a flowchart for explaining an example of the received power determination process performed in S412 of FIG. The received power determination process performed in S412 of FIG. 4 is based on the voltage output from the rectifying / smoothing unit 203 in order to determine whether the received power of the electronic device 200 is insufficient, appropriate, or excessive. It is processing of.

  In step S <b> 501, the CPU 205 determines whether the power maintenance flag stored in the second memory 207 is “0” or “1”. Here, the power maintenance flag is a state flag indicating whether or not the received power of the electronic device 200 exists in the appropriate power range. For example, when the power maintenance flag is “1”, the CPU 205 determines that the power maintenance state should be set. When the power maintenance flag is “0”, the CPU 205 determines that it is necessary to perform processing for detecting excess or deficiency of power. If the received power of the electronic device 200 is not in the proper power range, the CPU 205 determines whether the received power of the electronic device 200 is in any of the lower power lower limit area, the power shortage area, the power excessive area, and the power upper limit area. Determine. When the power maintenance flag is “1”, the CPU 205 determines that the power maintenance state should be maintained regardless of whether or not the current received power is in the appropriate power range. Then, the CPU 205 transmits information indicating that the received power is appropriate to the power transmitting apparatus 100 or information requesting maintenance of the output value of the transmitted power in the state information.

  As a result of the determination in S501, if the power maintenance flag is “0”, the CPU 205 proceeds to S502 in order to perform a process of detecting whether the power is excessive or insufficient. On the other hand, if the power maintenance flag is “1”, the process proceeds to S516 to determine whether or not to cancel the power maintenance state.

  In step S <b> 502, the CPU 205 determines whether the voltage level output from the rectifying / smoothing unit 203 is equal to or lower than the lower limit value. When the CPU 205 determines that the level of the voltage output from the rectifying / smoothing unit 203 is equal to or lower than the lower limit value, the process proceeds to S503, and when the CPU 205 determines that the voltage level is higher than the lower limit value, the process proceeds to S505.

  In step S503, the CPU 205 stores area information indicating that the current received power is in an area below the lower power limit in the second memory 207, and proceeds to step S504.

  In step S504, the CPU 205 performs a first determination process. When the first determination process ends, the CPU 205 ends the received power determination process of S412 and proceeds to S403. Details of the first determination process in S504 will be described later with reference to FIG.

  On the other hand, in S505, the CPU 205 determines whether or not the level of the voltage output from the rectifying and smoothing unit 203 is equal to or lower than the first threshold value. If the CPU 205 determines that the level of the voltage output from the rectifying / smoothing unit 203 is equal to or lower than the first threshold value, the process proceeds to S506, and if the CPU 205 determines that the voltage level is greater than the first threshold value, the process proceeds to S508. .

In S506, the CPU 205 stores area information indicating that the current received power is in the power shortage area in the second memory 207, and proceeds to S507.
In step S507, the CPU 205 performs a second determination process. When the second determination process ends, the CPU 205 ends the received power determination process of S412 and proceeds to S403. Details of the second determination process will be described later with reference to FIG.

  On the other hand, in S508, the CPU 205 determines whether the level of the voltage output from the rectifying / smoothing unit 203 is equal to or lower than the second threshold value. If the CPU 205 determines that the level of the voltage output from the rectifying / smoothing unit 203 is equal to or lower than the second threshold value, the process proceeds to S509. If the CPU 205 determines that the voltage level is not equal to or lower than the second threshold value, the process proceeds to S511. Proceed to

In S509, the CPU 205 stores area information indicating that the current received power is in the appropriate power area in the second memory 207, and proceeds to S510.
In step S510, the CPU 205 performs a third determination process. When the third determination process ends, the CPU 205 ends the received power determination process of S412 and proceeds to S403. Details of the third determination process will be described later with reference to FIG.

  On the other hand, in S511, the CPU 205 determines whether or not the level of the voltage output from the rectifying and smoothing unit 203 is equal to or lower than the upper limit value. If the CPU 205 determines that the level of the voltage output from the rectifying / smoothing unit 203 is equal to or lower than the upper limit value, the process proceeds to S512. If the CPU 205 determines that the voltage level is greater than the upper limit value, the process proceeds to S514.

In S512, the CPU 205 stores area information indicating that the current received power is in the excessive power area in the second memory 207, and proceeds to S513.
In step S513, the CPU 205 performs a fourth determination process. When the fourth determination process ends, the CPU 205 ends the received power determination process of S412 and proceeds to S403. Details of the fourth determination process will be described later with reference to FIG.

On the other hand, in S514, the CPU 205 stores area information indicating that the current received power is in the area exceeding the power upper limit in the second memory 207, and proceeds to S515.
In step S515, the CPU 205 performs a fifth determination process. When the fifth determination process ends, the CPU 205 ends the received power determination process of S412 and proceeds to S403. Details of the fifth determination process will be described later with reference to FIG.

  On the other hand, in S516, the CPU 205 performs a process of determining whether or not to cancel the power maintenance state. Then, the CPU 205 ends the received power determination process of S412 and proceeds to S403. The details of the process for determining whether to cancel the power maintenance state will be described later with reference to FIG.

  As described above, in the received power determination process performed in S412, the state information to be transmitted to the power transmission apparatus 100 in S405 of FIG. 4 can be determined based on the level of the voltage output from the rectifying and smoothing unit 203.

  FIG. 6 is a flowchart for explaining an example of the first determination process performed in S504 of FIG.

  In step S <b> 601, the CPU 205 determines from the area information stored in the second memory 207 whether the previous area is an area exceeding the power upper limit. The information referred to in this process is not the current area information stored in the previous S503, but the previous area information stored in S503, S506, S509, S512, or S514 in the previous process. For example, if the previous area information is an appropriate power area, it is determined in S601 that the previous area information is not an area exceeding the power upper limit, and the process proceeds to S603. On the other hand, if the previous area information is stored in the power upper limit exceeded area and the second memory 207, in S601, the CPU 205 determines that the previous area information is the power upper limit exceeded area, and proceeds to S602.

  In step S602, the CPU 205 determines that power transmission is stopped and ends the first determination process. Here, the reason why the CPU 205 determines that the power transmission is stopped is that the received power continuously exceeds the upper limit value and the lower limit value because the previous time is the power upper limit exceeded region and the current is the lower power lower limit region. The power transmission device 100 determines that power transmission is stopped because the transmission power cannot be supplied to the electronic device 200 between the upper limit value and the lower limit value. Thereafter, in S404, the power transmission stop request information is included in the status information transmitted to the power transmission device 100 in S405 again. The power transmission device 100 confirms the power transmission stop request information in the state information, determines that power transmission is not necessary in S307 of FIG. 3, and transmits a power transmission end instruction to the electronic device 200 in S308.

  On the other hand, in S603, the CPU 205 determines whether or not the previous area is an excessive power area. If the CPU 205 determines that the previous area is an excessive power area, the process proceeds to S604. If the CPU 205 determines that the previous area is not an excessive power area, the process proceeds to S605.

  In step S <b> 604, the CPU 205 adds 1 to the count value N and stores it in the second memory 207. Here, the count value N is not an appropriate power range in which the received power is between the first threshold value and the second threshold value, but is an excessive power region or a power upper limit region and a power shortage region or a power lower limit value excess region. This is a value for counting the number of times that are alternately repeated. The example shown in FIG. 12 shows an example in which the received power of the electronic device 200 is not in the proper power range, and the excessive power region or the upper power limit region and the insufficient power region or the lower power limit value region are alternately repeated. . Thus, in a state where the received power of the electronic device 200 is not stable and excessive power and insufficient power are repeated, the count value N is 2 or more, indicating that the state of the received power is unstable.

  In step S605, since the current region is below the lower power limit, the CPU 205 determines that the power is insufficient, and ends the first determination process. After that, in S404, the status information transmitted to the power transmission apparatus 100 in S405 again includes information indicating that the power is insufficient or information requesting to increase the transmission power. Then, the power transmission device 100 determines that it is necessary to increase the transmission power because the state information includes information indicating that the power is insufficient in S314, and performs control to increase the transmission power.

  In this way, in S404, the CPU 205 can add information indicating the result of the first determination process (power transmission stoppage or power shortage) to the state information as information indicating the result of the received power determination process. In step S <b> 405, the CPU 205 can notify the power transmission apparatus 100 of information indicating the result of the first determination process as information indicating the result of the received power determination process. Thereby, the power transmission apparatus 100 can appropriately control power transmission to the electronic device 200 based on the state information of the electronic device 200.

  FIG. 7 is a flowchart for explaining an example of the second determination process performed in S507 of FIG.

  In step S <b> 701, the CPU 205 determines from the area information stored in the second memory 207 whether the previous area is an area exceeding the power upper limit. If the CPU 205 determines that the previous area is an area exceeding the power upper limit, the process proceeds to S702. If the CPU 205 determines that the previous area is not an area exceeding the power upper limit, the process proceeds to S706.

  In S702, the CPU 205 adds 1 to the count value N and stores it in the second memory 207, and proceeds to S703. In step S <b> 703, the CPU 205 determines whether the count value N stored in the second memory 207 is 3 or more. As a result of the determination, if the count value N is 3 or more, the process proceeds to S704, and if the count value N is less than 3, the process proceeds to S708. As described above, the count value N is a number obtained by alternately repeating excessive and insufficient received power. Therefore, it can be said that the received power is not stable when the received power is alternately repeated three times or more. In the first embodiment, the received power is not stable when the count value N is 3 or more, but may be 5 or more, for example.

  In step S <b> 704, the CPU 205 sets the power maintenance flag stored in the second memory 207 to “1”. By setting the power maintenance flag to “1”, the process proceeds to S516 in the next processing of S501, and it is determined whether to continue or cancel the power maintenance in a stable state.

  In step S705, the CPU 205 determines that the power is appropriate and ends the second determination process. Here, the reason for determining that the power is appropriate is to perform the process of S516 in the next process. By the processing in S704 and S705, it is possible to control the power transmission device 100 so that the received power is stabilized in the power shortage region. Here, there are three areas where the power is stable, and there are an appropriate power area, an excessive power area, and an insufficient power area. The case where the processes of S704 and S705 are performed is a stable area in the insufficient power area.

  The power appropriate area is the best state as the received power because of its high efficiency. The excessive power region is a region that does not cause power shortage as a system of the electronic device 200 although efficiency is inferior. In the power shortage region, the efficiency is not better than that in the power appropriate region, and the electronic device 200 may stop due to power shortage. However, when the transmission power is increased, the power excess area is exceeded and the power upper limit is exceeded, so the power shortage area is the third best state when it is stable. After that, in S404, information indicating that the power is appropriate or information requesting to maintain the output value of the transmission power is included in the state information transmitted to the power transmission apparatus 100 in S405 again.

  On the other hand, in S706, the CPU 205 determines whether or not the previous area is an excessive power area from the area information stored also in the second memory 207. If the CPU 205 determines that the previous area is an excessive power area, the process proceeds to S707. If the CPU 205 determines that the previous area is not an excessive power area, the process proceeds to S708.

  In step S707, the CPU 205 adds 1 to the count value N and proceeds to step S708 because the received power is not stable because the received power is in an excessive power to insufficient power region.

  In step S <b> 708, the CPU 205 determines that power is insufficient because the current region is a power shortage region, and ends the second determination process. After that, in S404, the status information transmitted to the power transmission apparatus 100 in S405 again includes information indicating that the power is insufficient or information requesting to increase the transmission power. Then, the power transmission device 100 determines that it is necessary to increase the transmission power because the state information includes information indicating that the power is insufficient in S314, and performs control to increase the transmission power.

  Here, the reason why it is not determined whether or not the count value N is 3 or more after the processing of S707 is that the power transmission apparatus 100 is notified of power shortage in the next S405, and the power transmission apparatus 100 increases the transmission power. Because. The power transmission device 100 increases the transmitted power to cause the received power to be in an excessive power region, and then sets the power maintenance flag to “1”. Details of this processing will be described later with reference to FIG.

  Thus, in S404, the CPU 205 can add information indicating the result of the second determination process (power transmission shortage or power appropriateness) to the state information as information indicating the result of the received power determination process. In step S <b> 405, the CPU 205 can notify the power transmission apparatus 100 of information indicating the result of the second determination process as information indicating the result of the received power determination process. Thereby, the power transmission apparatus 100 can appropriately control power transmission to the electronic device 200 based on the state information of the electronic device 200.

  FIG. 8 is a flowchart for explaining an example of the third determination process performed in S510 of FIG.

  In step S <b> 801, the CPU 205 resets the count value N indicating that the received power is unstable because the received power is a stable region.

  In step S <b> 802, since the received power is stable, the CPU 205 sets a power maintenance flag for forcibly determining power maintenance to “0”. In step S803, the CPU 205 determines that the power is appropriate, and ends the third determination process. After that, in S404, information indicating that the power is appropriate or information requesting to maintain the output value of the transmission power is included in the state information transmitted to the power transmission apparatus 100 in S405 again.

  FIG. 9 is a flowchart for explaining an example of the fourth determination process performed in S513 of FIG.

  In step S <b> 901, the CPU 205 determines from the region information stored in the second memory 207 whether the previous region is a region below the lower power limit or a power shortage region. If the CPU 205 determines that the previous area is an area below the lower power limit or an insufficient power area, the process proceeds to step S902. If the previous area is determined not to be an area below the lower power limit or an insufficient power area, the process proceeds to step S906.

  In step S902, the CPU 205 adds 1 to the count value N and stores it in the second memory 207, and proceeds to step S903. In step S <b> 903, the CPU 205 determines whether the count value N stored in the second memory 207 is 3 or more. As a result of the determination, if the count value N is 3 or more, the process proceeds to S904, and if the count value N is less than 3, the process proceeds to S906.

  In step S <b> 904, the CPU 205 sets the power maintenance flag stored in the second memory 207 to “1”. The reason for setting the power maintenance flag to “1” is the same reason as in the case of S704. In step S905, the CPU 205 determines that the power is appropriate, and ends the fourth determination process. The reason for determining that the power is appropriate is the same reason as in S705. As a result, it is possible to perform control so that the received power is stabilized as an excessive power region. After that, in S404, information indicating that the power is appropriate or information requesting to maintain the output value of the transmission power is included in the state information transmitted to the power transmission apparatus 100 in S405 again.

  On the other hand, in S906, the CPU 205 determines that the received power is excessive, and ends the fourth determination process. After that, in S404, the status information transmitted to the power transmission device 100 in S405 again includes information indicating that the received power is excessive or information requesting to reduce the transmitted power. In step S314, the power transmission device 100 determines that the transmitted power needs to be reduced because the state information includes information indicating that the received power is excessive, and performs control to decrease the transmitted power.

  As described above, the CPU 205 can add information indicating the result of the third determination process (excessive power or appropriate power) to the state information as information indicating the result of the received power determination process in S404. In step S <b> 405, the CPU 205 can notify the power transmission apparatus 100 of information indicating the result of the third determination process as information indicating the result of the received power determination process. Thereby, the power transmission apparatus 100 can appropriately control power transmission to the electronic device 200 based on the state information of the electronic device 200.

  FIG. 10 is a flowchart for explaining an example of the fifth determination process performed in S515 of FIG.

  In step S <b> 1001, the CPU 205 determines from the region information stored in the second memory 207 whether the previous region is a region below the lower power limit. If the CPU 205 determines that the previous area is an area below the lower power limit, the process proceeds to S1002, and if the previous area is not an area exceeding the lower power limit, the process proceeds to S1003.

  In step S1002, the CPU 205 determines that power transmission is stopped and ends the fifth determination process. The reason why the CPU 205 determines that power transmission is stopped is that the received power continuously exceeds the upper limit and the lower limit, as in the case of S602. Thereafter, in S404, the power transmission stop request information is included in the status information transmitted to the power transmission device 100 in S405 again. The power transmission device 100 confirms the power transmission stop request information in the state information, determines that power transmission is not necessary in S307 of FIG. 3, and transmits a power transmission end instruction to the electronic device 200 in S308.

  On the other hand, in S1003, the CPU 205 determines whether or not the previous area is a power shortage area. If the CPU 205 determines that the previous area is a power shortage area, the process proceeds to S1004. If the CPU 205 determines that the previous area is not a power shortage area, the process proceeds to S1005.

  In S1004, the CPU 205 adds 1 to the count value N, stores it in the second memory 207, and proceeds to S1005. In step S1005, the CPU 205 determines that the power is excessive and ends the fifth determination process. After that, in S404, the status information transmitted to the power transmission device 100 in S405 again includes information indicating that the received power is excessive or information requesting to reduce the transmitted power. In step S314, the power transmission device 100 determines that the transmitted power needs to be reduced because the state information includes information indicating that the received power is excessive, and performs control to decrease the transmitted power.

  In this manner, in S404, the CPU 205 can add information indicating the result of the fourth determination process (power transmission stoppage or excessive power) to the state information as information indicating the result of the received power determination process. In step S <b> 405, the CPU 205 can notify the power transmission apparatus 100 of information indicating the result of the fourth determination process as information indicating the result of the received power determination process. Thereby, the power transmission apparatus 100 can appropriately control power transmission to the electronic device 200 based on the state information of the electronic device 200.

  FIG. 11 is a flowchart for explaining an example of the release determination process performed in S516 of FIG. As described above, when the CPU 205 determines that the power maintenance flag is “1” in S <b> 501, control is performed so that the received power is maintained in the excessive region or the insufficient region. Therefore, in S516, it is determined whether or not to cancel the power maintenance state.

  In step S <b> 1101, the CPU 205 adds 1 to the maintenance count value M and stores it in the second memory 207. Here, the maintenance count value M is a count value for counting the number of times the process of S516 is performed when the power maintenance flag is determined to be “1” in S501.

  In step S1102, the CPU 205 determines whether or not the maintenance count value M is 10 or more. As a result of this determination, if the maintenance count value M is 10 or more, the CPU 205 proceeds to S1104 to cancel the power maintenance, and if the maintenance count value M is less than 10, the process proceeds to S1103 to continue the power maintenance. move on. Here, the maintenance count value M, which is a criterion for determination, may not be 10. If the power maintenance state is to be continued for a long time, it may be 11 or more, and if it is to be shortened, it may be 9 or less. Good.

  In step S1103, the CPU 205 determines whether the load of the electronic device 200 has fluctuated by a certain value or more. If the CPU 205 determines that the load has fluctuated by a certain value or more, the process proceeds to S1104 to cancel the power maintenance. If the CPU 205 determines that the load has not fluctuated by a certain value or more, the process is terminated to continue the power maintenance. After that, in S404, information indicating that the power is appropriate or information requesting to maintain the output value of the transmission power is included in the state information transmitted to the power transmission apparatus 100 in S405 again.

  Here, the load of the electronic device 200 is a load for DC power output from the rectifying and smoothing unit 203. The CPU 205 detects the current and voltage output from the rectifying / smoothing unit 203, and detects load fluctuations from the values. The constant value of load fluctuation is, for example, 200 mW. When the output from the rectifying / smoothing unit 203 becomes larger or smaller than 200 mW, the CPU 205 determines that the load has fluctuated more than a certain level. Since the received power of the electronic device 200 changes when the load fluctuates, the power transmission device 100 is requested to increase or decrease the transmitted power. Thereby, in order to make the received power of the electronic device 200 appropriate, it is determined to cancel the power maintenance state.

  In step S1104, the CPU 205 resets the count value N and the maintenance count value M to “0” in order to cancel the power maintenance. In step S1105, the CPU 205 sets the power maintenance flag to “0”. In step S <b> 1106, the CPU 205 determines that the power is appropriate in order to return to the initial state, and ends the release determination process. After that, in S404, information indicating that the power is appropriate or information requesting to maintain the output value of the transmission power is included in the state information transmitted to the power transmission apparatus 100 in S405 again.

  As described above, once the power maintenance flag is set to “1”, the CPU 205 cancels the power maintenance state depending on whether the power maintenance state is repeated 10 times or the load fluctuates more than a certain value. In step S1102, the electronic device 200 determines whether to cancel the power maintenance based on the maintenance count value M, but the timer 211 counts the count value, and the count value reaches a predetermined time (for example, 3 minutes). Whether or not to cancel the power maintenance may be determined based on whether or not the power maintenance is performed.

  FIG. 13 is a diagram illustrating an example of a temporal change in the voltage output from the rectifying and smoothing unit 203 before the unstable state is changed to the stable state.

  The example illustrated in FIG. 13 indicates that the state where the received power shifts to the power shortage region after shifting to the power excessive region and then shifts to the power excessive region again is repeated a predetermined number of times. In the example illustrated in FIG. 9, the count value N = 3, and thereafter, in order to stabilize the power, the process proceeds to S904 and the power maintenance flag is set to “1”. Then, the electronic device 200 transmits power status as status information to the power transmission apparatus 100, and the received power is maintained. In the example shown in FIG. 13, the power maintenance frequency is repeated 10 times thereafter, and the maintenance frequency count M = 10 is reached, so that the power maintenance is released. Since the electronic device 200 again determines in S906 that the received power is in the excessive power region, the power transmission device 100 reduces the transmitted power so that the received power is transferred to the appropriate power region.

  As described above, according to the first embodiment, for example, it is possible to perform control so that unstable received power as illustrated in FIG. 12 becomes stable received power as illustrated in FIG. 13.

[Embodiment 2]
The various functions, processes, and methods described in the first and second embodiments can also be realized by using a program by a personal computer, a microcomputer, a CPU (Central Processing Unit), or the like. Hereinafter, in the third embodiment, a personal computer, a microcomputer, a CPU, and the like are referred to as “computer X”. In the third embodiment, a program for controlling the computer X and realizing the various functions, processes, and methods described in the first and second embodiments is referred to as “program Y”.

  The various functions, processes, and methods described in the first and second embodiments are realized by the computer X executing the program Y. In this case, the program Y is supplied to the computer X via a computer-readable storage medium. The computer-readable storage medium according to the third embodiment includes at least one of a hard disk device, a magnetic storage device, an optical storage device, a magneto-optical storage device, a memory card, a volatile memory, and a nonvolatile memory. The computer-readable storage medium in the third embodiment is a non-transitory storage medium.

201 Antenna 204 Communication Control Unit 205 CPU

Claims (11)

Power receiving means for receiving power wirelessly from the power transmitting device;
Detecting means for detecting whether the power received by the power receiving means is insufficient, excessive or appropriate;
Generating means for generating, as state information, information indicating that the power received by the power receiving means is insufficient, excessive, or appropriate based on the detection result of the detection means;
Communication means for transmitting the state information generated by the generation means to the power transmission device;
When the detection unit alternately detects a shortage and an excess of the predetermined number of times, the generation unit changes the control to generate state information indicating that the power received by the power reception unit is appropriate. Features electronic equipment.   When the detecting means detects that the power received by the power receiving means is insufficient, it further detects whether or not the power is below a lower limit, and the power received by the power receiving means is excessive. The electronic device according to claim 1, further comprising detecting whether or not the power is larger than an upper limit value when it is detected. A request indicating that the generation means stops power transmission when the power received by the power reception means is alternately detected by the detection means in a state where the power is less than or equal to the lower limit value and in a state where the power is greater than the upper limit value. Generate information,
The electronic device according to claim 2, wherein the communication unit transmits request information indicating that the power transmission is to be stopped to the power transmission device.   The power received by the power receiving means by the detecting means is detected by the power receiving means by the detecting means after being alternately detected a predetermined number of times in an insufficiency state and in excess and below the upper limit value. When the generated power is detected to be excessive and less than or equal to the upper limit value, the generating means changes to control that generates state information indicating that the power received by the power receiving means is appropriate. The electronic device according to claim 2, wherein:   The power received by the power receiving means by the detecting means is detected by the power receiving means by the detecting means after being alternately detected a predetermined number of times in an excessive state and a shortage and being larger than the lower limit value. When the generated power is detected to be insufficient and greater than the lower limit value, the generating means changes to control for generating status information indicating that the power received by the power receiving means is appropriate. The electronic device according to claim 2, wherein:   The electronic apparatus according to claim 2, wherein the upper limit value is a maximum value that makes unnecessary power consumption unnecessary.   The electronic device according to claim 2, wherein the lower limit value is a minimum value at which the electronic device can operate normally. The detection means further detects a change in a load that consumes the received power,
8. The control unit according to claim 1, wherein the generation unit cancels the control to generate the state information indicating that the load is appropriate when the detection unit detects a load fluctuation of a predetermined value or more. Item 1. An electronic device according to item 1.   The electronic device according to claim 1, wherein the detection unit detects that the efficiency of the received power is appropriate when the efficiency of the received power is a predetermined value or more. A power receiving step for receiving power wirelessly from a power transmitting device;
Detecting whether the power received by the power receiving step is insufficient, excessive or appropriate;
Based on the detection result of the detection step, a generation step of generating information indicating that the power received by the power reception step is insufficient, excessive, or appropriate as state information;
A communication step of transmitting the state information generated by the generation step to the power transmission device,
When the detection step alternately detects deficiency and excess for a predetermined number of times, the generation step changes to control that generates state information indicating that the power received by the power reception step is appropriate. Characteristic control method. Computer
Power receiving means for receiving power wirelessly from the power transmitting device;
Detecting means for detecting whether the power received by the power receiving means is insufficient, excessive or appropriate;
Generating means for generating, as state information, information indicating that the power received by the power receiving means is insufficient, excessive, or appropriate based on the detection result of the detection means;
A program for causing the state information generated by the generation unit to function as a communication unit that transmits to the power transmission device,
When the detection means alternately detects a shortage and an excess of a predetermined number of times, the generation means changes to control that generates state information indicating that the power received by the power reception means is appropriate. A program for causing the computer to function.

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