JP2017099230A - Wireless power transmission apparatus and processor thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wireless power transmission device capable of stable operation if a variety of hosts/charge adapters are connected.SOLUTION: An external host/charge adapter 104 is connected to a receptacle 208. A control unit 360 controls inverter circuit 204 on the basis of a control parameter PRM stored in a register 354. A negotiation unit 302 communicates with the host/charge adapter 104 connected to the receptacle 208, to determine a voltage value of a bus voltage V. A memory 304 holds a plurality of set data D1 corresponding to a plurality of candidates of voltage values of the bus voltage V. A control parameter generation unit 306 generates the control parameter PRM on the basis of the set data D1 corresponding to the voltage value of the bus voltage Vdetermined by the negotiation, to write the control parameter PRM into the register 354.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a wireless power feeding technique.

  In recent years, wireless power feeding that supplies electric power to electronic devices without connection by a cable has begun to spread. In order to promote mutual use between products of different manufacturers, the WPC (Wireless Power Consortium) was organized, and the international standard Qi (Qi) standard was formulated by WPC. Wireless power supply based on the Qi standard uses electromagnetic induction between a transmission coil and a reception coil. The power feeding system includes a power feeding device (TX: Transmitter) having a transmission coil and a power receiving terminal (RX: Receiver) having a receiving coil.

  FIG. 1 is a diagram illustrating a configuration of a wireless power feeding system 10 compliant with the Qi standard. The power feeding system 10 includes a power transmission device 20 (TX, Power Transmitter) and a power reception device 30 (RX, Power Receiver). The power receiving device 30 is mounted on an electronic device such as a mobile phone terminal, a smart phone, an audio player, a game device, or a tablet terminal.

  The power transmission device 20 includes a transmission coil (primary coil) 22, an inverter circuit 24, a controller 26, and a demodulator 28. The inverter circuit 24 includes an H-bridge circuit (full-bridge circuit) or a half-bridge circuit, and applies a drive signal S 1, specifically a pulse signal, to the transmission coil 22, and the transmission coil 22 is driven by a drive current flowing through the transmission coil 22. An electromagnetic field power signal S2 is generated. The controller 26 comprehensively controls the power transmission device 20 as a whole.

  In the Qi standard, a communication protocol is defined between the power transmission device 20 and the power reception device 30, and information can be transmitted from the power reception device 30 to the power transmission device 20 using the control signal S3. The control signal S3 is transmitted from the reception coil 32 (secondary coil) to the transmission coil 22 in a form of AM (Amplitude Modulation) modulation using backscatter modulation. The control signal S3 includes, for example, power control data (also referred to as a packet) for controlling the amount of power supplied to the power receiving device 30, data indicating unique information of the power receiving device 30, and the like. The demodulator 28 demodulates the control signal S3 based on the current or voltage of the transmission coil 22. The controller 26 controls the inverter circuit 24 based on the power control data included in the demodulated control signal S3.

The power receiving device 30 includes a receiving coil 32, a rectifier circuit 34, a smoothing capacitor 36, a modulator 38, a load 40, a controller 42, and a power supply circuit 44. The reception coil 32 receives the power signal S <b> 2 from the transmission coil 22 and transmits a control signal S <b> 3 to the transmission coil 22. The rectifier circuit 34 and the smoothing capacitor 36 rectify and smooth the current S4 induced in the receiving coil 32 in accordance with the power signal S2, and convert it into a DC voltage V _RECT .

The power supply circuit 44 uses a power supplied from the power transmission device 20 to charge a secondary battery (not shown), or boosts or steps down the DC voltage V _RECT and supplies it to the controller 42 and other loads 40.

The controller 42 generates power control data (also referred to as a control error packet or a CE packet) that controls the amount of power supplied from the power transmission device 20 so that the rectified voltage V _RECT approaches its target value. The modulator 38 modulates the coil current and the coil voltage of the transmission coil 22 by modulating the control signal S3 including the power control data and modulating the coil current of the reception coil 32.

  The Qi standard was originally formulated for low power consumption of 5W or less, such as mobile phone terminals, smart phones, and tablet terminals (Volume I Low Power, hereinafter referred to as the Low Power standard). Subsequently, preparations for formulating medium power up to 15 W (Volume II Middle Power, hereinafter referred to as Middle Power standard) are proceeding, and it is planned to support 120 W of high power in the future.

JP 2013-038854 A JP 2014-107971 A

  The present inventor examined adopting a USB (Universal Serial Bus) interface from the viewpoint of versatility and effective use of existing infrastructure for power feeding to the power transmission device 20 of FIG.

  As a next-generation secondary battery charging method and system using USB, a standard called USB Power Delivery (hereinafter referred to as PD standard) has been established. In the PD standard, the power that can be supplied is greatly increased from 7.5 W of the conventional USB Battery Charging Specification (BC standard) to a maximum of 100 W. Specifically, in the PD standard, supply of a voltage (specifically, 12 V, 20 V) higher than 5 V of the BC standard is allowed as the USB bus voltage, and the current is also the amount of the BC standard (100 mA, 500 mA, 900mA, 1500mA) (specifically, 2A, 3A, 5A) is allowed to be supplied.

  As described above, in the current USB interface, there are a wide variety of combinations of bus voltage and current capacity for each host and charging adapter (hereinafter referred to as a host / charging adapter). Therefore, when the USB interface is used for power supply to the power transmission device 20, the operation may become unstable depending on the voltage value (or current amount) of the bus voltage supplied from the host / charge adapter. Specifically, there may arise problems that sufficient power cannot be supplied to the power receiving device 30, power supply efficiency is reduced, or foreign object detection fails. The same problem can occur not only when the USB interface is used, but also when another power supply interface capable of selecting a plurality of bus voltages and charging currents is employed.

  The present invention has been made in such a situation, and one of exemplary purposes of an aspect thereof is to provide a wireless power transmission apparatus that can stably operate even when various host / charge adapters are connected.

  An embodiment of the present invention relates to a processor (signal processing device) used in a wireless power transmission device that transmits a power signal to the wireless power reception device. The wireless power transmission apparatus is connected to an external host / charge adapter in addition to a processor, receives a bus voltage, a transmission antenna including a transmission coil, receives the bus voltage, and applies an AC drive signal to the transmission antenna. An inverter circuit and a control circuit for controlling the inverter circuit are provided. The control circuit includes a register and a transmission control unit that controls the inverter circuit based on a control parameter stored in the register. The processor communicates with a host / charge adapter connected to the receptacle, determines a voltage value of the bus voltage, a memory holding a plurality of setting data corresponding to a plurality of candidates of the voltage value of the bus voltage, A control parameter generation unit that generates a control parameter based on setting data corresponding to the voltage value of the bus voltage determined by the negotiation and writes the control parameter to a register.

  Instead of always operating the wireless power transmission device with the same parameters, methods, methods or conditions regardless of the voltage value of the bus voltage, by switching them according to the voltage value of the bus voltage selected as a result of the negotiation, Stable operation is possible.

  The setting data may include a threshold value used for foreign object detection based on a comparison between the Q value measured before the start of power supply and the Q value information received from the wireless power receiving apparatus. The setting data may include a threshold value used for foreign object detection by the power loss method. The setting data may include at least one of a frequency and a duty ratio of an analog pin for detection of the wireless power receiving apparatus. The setting data may include at least one of the frequency and duty ratio of the digital pin after detection by the wireless power receiving apparatus. The setting data may include at least one variable range of frequency, duty ratio, and phase in the power transfer phase. The setting data may include a constant value for PID (proportional integral derivative) control for power stabilization in the power transfer phase.

  The inverter circuit may include an H bridge circuit. The setting data may include a condition for switching between a half-bridge operation and a full-bridge operation of the inverter circuit. The setting data may include a microprogram or firmware that defines the operation of the control parameter generation unit.

  The memory further holds a first list that defines a plurality of candidates for bus voltage values and respective priorities, and the negotiation unit negotiates so that a higher priority voltage value is selected. Also good.

  The processor outputs an error signal when the host / charge adapter does not support all candidates of bus voltage values included in the first list, and the control circuit does not supply power when receiving the error signal. Also good.

  The wireless power transmission apparatus may further include a DC / DC converter that receives the bus voltage and converts the voltage level. The DC / DC converter may convert the bus voltage supplied from the host / charge adapter into one of the bus voltage candidates when the host / charge adapter does not support all candidates of the bus voltage value.

  The memory may further maintain a second list that defines candidate voltage values of the bus voltage that can be input to the DC / DC converter.

  The control parameter may include at least one of information relating to the switching frequency, duty ratio, phase, and foreign object detection of the inverter circuit.

  The wireless power transmission device may conform to the Qi standard. The host / charge adapter may conform to the USB standard.

The processor may be integrated on a single semiconductor substrate. The processor may constitute one module together with the control circuit. The processor and the control circuit may be integrated on a single semiconductor substrate.
“Integrated integration” includes the case where all of the circuit components are formed on a semiconductor substrate and the case where the main components of the circuit are integrated. A resistor, a capacitor, or the like may be provided outside the semiconductor substrate.
By integrating the circuit on one chip, the circuit area can be reduced and the characteristics of the circuit elements can be kept uniform.

  Another aspect of the present invention relates to a wireless power transmission apparatus. A wireless power transmission apparatus includes a receptacle to which an external host / charge adapter is connected and receives a bus voltage, a transmission antenna including a transmission coil, an inverter circuit that receives the bus voltage and applies an AC drive signal to the transmission antenna, and an inverter You may provide the control circuit which controls a circuit, and one of the above-mentioned processors.

  Another aspect of the present invention is also a wireless power transmission device. A wireless power transmission apparatus includes a receptacle to which an external host / charge adapter is connected and receives a bus voltage, a transmission antenna including a transmission coil, an inverter circuit that receives the bus voltage and applies an AC drive signal to the transmission antenna, and a register A transmission control unit that controls the inverter circuit based on a control parameter stored in a register, a negotiation unit that communicates with a host / charge adapter connected to the receptacle and determines a voltage value of the bus voltage, and a bus voltage A memory that holds a plurality of setting data corresponding to a plurality of voltage value candidates, and a control parameter generation unit that generates a control parameter based on the setting data corresponding to the voltage value of the bus voltage determined by the negotiation and writes the control parameter to the register And comprising.

  It should be noted that any combination of the above-described constituent elements, and those in which constituent elements and expressions of the present invention are mutually replaced between methods, apparatuses, systems, and the like are also effective as an aspect of the present invention.

  According to an aspect of the present invention, it is possible to deal with bus voltages having various voltage values.

It is a figure which shows the structure of the wireless electric power feeding system based on Qi specification. It is a block diagram of the electric power feeding system which concerns on 2nd Embodiment. It is a figure which shows the state transition of a power transfer phase. It is a block diagram of the power transmission apparatus which concerns on 2nd Embodiment. It is a figure which shows a charger provided with a power transmission apparatus.

  The present invention will be described below based on preferred embodiments with reference to the drawings. The same or equivalent components, members, and processes shown in the drawings are denoted by the same reference numerals, and repeated descriptions are omitted as appropriate. The embodiments do not limit the invention but are exemplifications, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention.

In this specification, “the state in which the member A is connected to the member B” means that the member A and the member B are electrically connected to each other in addition to the case where the member A and the member B are physically directly connected. It includes cases where the connection is indirectly made through other members that do not substantially affect the general connection state, or that do not impair the functions and effects achieved by their combination.
Similarly, “the state in which the member C is provided between the member A and the member B” refers to the case where the member A and the member C or the member B and the member C are directly connected, as well as their electric It includes cases where the connection is indirectly made through other members that do not substantially affect the general connection state, or that do not impair the functions and effects achieved by their combination.

(First embodiment)
FIG. 2 is a block diagram of a power feeding system 100 according to the second embodiment. The power supply system 100 includes a power transmission device 200 (TX, Power Transmitter) and a power reception device 400 (RX, Power Receiver). The power receiving device 400 is mounted on an electronic device such as a mobile phone terminal, a smart phone, an audio player, a game device, or a tablet terminal. Hereinafter, the power transmission device 200 and the power reception device 400 will be described on the assumption that they conform to the Qi standard.

  The power transmission device 200 is mounted on, for example, a charger having a charging stand. The power transmission device 200 includes a transmission antenna 201, an inverter circuit 204, a receptacle 208, a processor 300, and a control circuit 350.

Receptacle 208 is provided for receiving a DC bus voltage (adapter voltage) V _ADP from the outside. Specifically, the external host / charge adapter 104 is detachably connected to the receptacle 208 via the cable 102 and supplied with a DC bus voltage V _ADP . In the present embodiment, it is assumed that the receptacle 208, the cable 102, and the host / charge adapter 104 conform to the USB standard.

The transmission antenna 201 includes a transmission coil (primary coil) 202 and a resonance capacitor 203 connected in series. The inverter circuit 204 is an H-bridge circuit (full-bridge circuit), receives the DC bus voltage V _ADP supplied from the host / charge adapter 104, converts it into an AC drive signal S 1, and supplies it to the transmitting antenna 201. The voltage amplitude of the drive signal S1 is proportional to the bus voltage _VADP . Due to the drive current flowing through the transmission coil 202, the transmission coil 202 is caused to generate a power signal S2 of an electromagnetic field. Note that the inverter circuit 204 may be a half-bridge circuit. A load switch SW11 may be inserted between the receptacle 208 and the inverter circuit 204.

The control circuit 350 controls the inverter circuit 204. The control circuit 350 includes an interface circuit 352, a register 354, a driver 356, and a transmission control unit 360, and is a functional IC integrated on one semiconductor substrate. The processor 300 and the control circuit 350 are connected via an internal bus 212. The internal bus 212 may be an I ² C bus, for example. The interface circuit 352 communicates with the processor 300 and stores the received data in the register 354. The transmission control unit 360 generates a control signal S5 for controlling the inverter circuit 204 based on the data (control parameter PRM) stored in the register 354. The control parameter PRM includes at least one of the switching frequency f of the inverter circuit 204, the duty ratio d, the phase α, the operation mode (half bridge / full bridge) of the inverter circuit 204, and information related to foreign object detection. The driver 356 drives the four transistors (first switch to fourth switch) SW1 to SW4 constituting the inverter circuit 204 based on the control signal S5 generated by the transmission control unit 360.

The processor 300 is mainly composed of a digital circuit. The processor 300 includes a negotiation unit 302, a memory 304, and a control parameter generation unit 306. The negotiation unit 302 communicates with the host / charge adapter 104 connected to the receptacle 208 to determine the voltage value of the bus voltage _VADP . For example, in the USB-PD standard, the negotiation unit 302 is connected to the bus line 210 via the capacitor C1. The negotiation unit 302 communicates with the host / charge adapter 104 via the bus line 210 and negotiates with the controller built in the host / charge adapter 104.

The power transmission device 200 supports a plurality of voltage values as the bus voltage _VADP . For example, the power transmission device 200 supports V _ADP = 5V, 9V, 12V, and 19V. The processor 300 holds a plurality of setting data D1 corresponding to a plurality of candidates (5, 9, 12, 19V) of the voltage value of the bus voltage V _ADP . The plurality of setting data D1 is stored in a nonvolatile memory 220 inside the processor 300 or externally attached. The non-volatile memory 220 includes a mask ROM (Read Only Memory), a PROM (Programmable ROM), an EPROM (Erasable Programmable Read Only Memory), an EEPROM (Electrically Erasable Programmable Read-Only Memory), a flash memory, a resistance change memory ( ReRAM), ferroelectric memory (FeRAM), or the like may be used.

The control parameter generation unit 306 generates the control parameter PRM based on the setting data D1 corresponding to the voltage value of the bus voltage V _ADP determined by the negotiation, and writes the control parameter PRM into the register 354 of the control circuit 350 via the interface circuit 352. The demodulator 308 is coupled to the transmission antenna 201 and demodulates the control signal S3 received by the transmission antenna 201. The demodulated data is used by the control parameter generation unit 306 to generate the control parameter PRM.

The above is the configuration of the power transmission device 200. The power transmission device 200, always the same parameters irrespective of the voltage value of the bus voltage V _ADP, method, process, operating under the conditions, depending on the voltage value of the bus voltage V _ADP, operation becomes unstable. On the other hand, in the present embodiment, the operation of the power feeding system 100 is performed by setting the parameter, method, method, or condition of the power transmission apparatus 200 based on the voltage value of the bus voltage V _ADP selected as a result of the negotiation. Can be stabilized. Specifically, it is possible to suppress a decrease in power supply efficiency, suppress a decrease in foreign object detection accuracy, or prevent malfunction.

  Next, the setting data D1 will be described in detail. The setting data D1 can include the following information.

1. In the Qi standard, the processor 300 is equipped with a foreign object detection (FOD) function. As an FOD method, a method that utilizes the fact that the Q value of an antenna changes according to the presence or absence of foreign matter has been proposed. Specifically, an initial value (normal value) of the Q value is measured before the start of power supply, compared with a measured value of the Q value received from the power receiving apparatus 400 after the start of power supply, and a difference ΔQ between the initial value and the measured value. _{Exceeds a} predetermined threshold value _QTH , it is determined that a foreign substance is present. When the control parameter generation unit 306 detects a foreign object, the control parameter generation unit 306 rewrites the control parameter PRM in the register 354 so that power supply is stopped or transmission power is reduced. When performing FOD based on such a Q value, the setting data D1 may include a threshold value _QTH . That is, the threshold value Q _TH is variable according to the bus voltage V _ADP .

The operating point (switching frequency, duty ratio, phase, etc.) of the inverter circuit 204 can change in accordance with the bus voltage V _ADP supplied to the inverter circuit 204. When the operating point changes, the initial Q value and the actual measurement value also change. Regardless of the voltage value of the bus voltage V _ADP , if the threshold value Q _TH is kept constant, a foreign object can be detected accurately at a certain voltage value, but a foreign object is detected erroneously or detected at another voltage value. The problem of not being able to occur can arise. By including the threshold value Q _TH in the setting data D1, it is possible to improve the accuracy of foreign object detection at various voltage values of the bus voltage V _ADP .

2. As another method of FOD, a power loss method may be used. The power loss method uses the fact that the reception power P _RX decreases when the foreign object absorbs part of the transmission power P _{TX in} a state where the foreign object exists. Specifically, in the power loss method, the power P _TX transmitted by the power transmitting apparatus 200 and the power P _RX received by the power receiving apparatus 400 are measured, and the difference ΔP = P _TX −P _RX is compared with the threshold value P _TH. When the difference ΔP is larger than the threshold value P _TH, it is determined that there is a foreign object. When the control parameter generation unit 306 detects a foreign object, the control parameter generation unit 306 rewrites the control parameter PRM in the register 354 so that power supply is stopped or transmission power is reduced. When performing FOD based on the power loss method, the setting data D1 may include a threshold value _PTH . That is, the threshold value P _TH is variable according to the bus voltage V _ADP .

The operating point (switching frequency, duty ratio, phase, etc.) of the inverter circuit 204 can change in accordance with the bus voltage V _ADP supplied to the inverter circuit 204. When the operating point changes, the power supply efficiency changes. Regardless of the voltage value of the bus voltage V _ADP , if the threshold value _PTH is kept constant, a foreign object can be detected accurately at a certain voltage value, but a foreign object is erroneously detected at another voltage value, or a foreign object is detected. The problem of not being able to occur can arise. By including the threshold value P _TH in the setting data D1, it is possible to improve the accuracy of foreign object detection at various voltage values of the bus voltage V _ADP .

3. In the power supply system 100 of the Qi standard, the power transmission device 200 executes an analog pin (Analog Ping) phase. The analog pin detects whether or not the power receiving device 400 is placed on the charging stand of the power transmitting device 200. In the analog pin phase, the power transmission device 200 supplies a short pulse including the operating frequency f _OD from the inverter circuit 204 to the transmission antenna 201. The resonance shift method uses the fact that the current flowing through the transmission coil 202 changes depending on whether or not the power receiving device 400 is present.

The operating point (switching frequency, duty ratio, phase, etc.) of the inverter circuit 204 can change in accordance with the bus voltage V _ADP supplied to the inverter circuit 204. Regardless of the voltage value of the bus voltage V _ADP , if the operating frequency f _OD or phase of the inverter circuit 204 in the analog pin phase is constant, the amount of change in the current of the coil 202 due to the presence or absence of the power receiving device 400 becomes minute, and the power receiving device 400 There may be a situation in which cannot be detected. Or, conversely, the current change becomes sensitive, and there is a possibility that the power receiving apparatus 400 is erroneously detected even though the power receiving apparatus 400 does not exist.

Therefore, the setting data D1 may include at least one of the operating frequency f _OD and the duty ratio of the inverter circuit 204 in the analog pin phase for detection by the power receiving device 400. Thereby, the power receiving apparatus 400 can be accurately detected in the analog pin phase.

4). In the power supply system 100 of the Qi standard, a digital pin (Digital Ping) phase is executed after the analog pin phase. At the digital pin, the power transmission device 200 generates a power signal at the operating point and maintains the transmission power constant. When the power transmission device 200 receives a response (packet) from the power reception device 400, the power transmission device 200 shifts to an authentication & configuration phase.

When the frequency and duty ratio are fixed, the transmission power at the digital pin deviates from the operating point according to the bus voltage V _ADP . Therefore, the setting data D1 may include at least one of the frequency of the digital pin and the duty ratio. Thereby, the transmission power at the digital pin can be kept constant regardless of the bus voltage V _ADP .

5. In the Qi standard, the power transmitting apparatus 200 adjusts the transmission power P _TX by PID (proportional integral derivative) control based on a control error (CE) packet from the power receiving apparatus 400 in the power transfer phase. The transmission power P _TX is controlled by changing at least one of the following operating conditions of the inverter circuit 204.
(1) Switching frequency of the inverter circuit 204 (frequency control)
(2) Duty ratio of inverter circuit 204 (duty ratio control)
(3) Switching phase of the inverter circuit 204 (phase control)

That is, in a certain power range (PID value range), the switching frequency is controlled in a certain variable range, and in a certain power range, the duty ratio is controlled in a certain variable range, and there is a switching phase in a certain power range. Controlled in a variable range. The transmission power P _TX when the inverter circuit 204 is operated under the same operating condition varies depending on the bus voltage V _ADP . In other words, the operating conditions required to obtain the desired transmission power P _TX is dependent on the bus voltage V _ADP.

Therefore, the setting data D1 may include at least one variable range of the switching frequency, duty ratio, and phase in the power transfer phase. Accordingly, an appropriate power signal S2 can be supplied based on a request from the power receiving device 400 regardless of the bus voltage V _ADP .

When the inverter circuit 204 is configured by an H bridge circuit, the half bridge operation and the full bridge operation may be switched depending on the range of transmission power. In this case, setting the data D1 is a condition for switching the half-bridge operation and full-bridge operation, it may be changed in accordance with the voltage value of the bus voltage V _ADP.

FIG. 3 is a diagram illustrating state transition in the power transfer phase. In the present embodiment, the control circuit 350 can select four modes, the first mode φ1 to the fourth mode φ4, according to the range of the desired transmission power P _TX (that is, the PID value). Each time the inverter circuit 204 is switched in a different manner.

(I) First mode φ1
In the first mode φ1, the inverter circuit 204 performs a full bridge operation in the following manner. The first pair SW1, SW2 is complementarily switched at a duty ratio of 50%, and the second pair SW3, SW4 is complementarily switched at a duty ratio of 50%. The switching frequency f is fixed at the first frequency f ₁ (for example, 160 kHz). The control circuit 350 changes the phase difference α between the first pair and the second pair between the minimum value α _MIN and the maximum value α _MAX according to the desired transmission power P _TX .

(Ii) Second mode φ2
In the second mode φ2, the inverter circuit 204 performs a half bridge operation in the following manner. The first pair SW1, SW2 is complementarily switched at a duty ratio of 50%, and the second pair SW3, SW4 is fixed with SW3 off and SW4 on. In a modification, SW3 may be turned off and SW4 may be turned on. In the second mode .phi.2, control circuit 350, the switching frequency f, between the first frequency _{f 1} and the second frequency _{f 2,} varies according to the desired transmission power _{P TX.}

(Iii) Third mode φ3
In the third mode φ3, the inverter circuit 204 performs a full bridge operation in the following manner. The first pair SW1, SW2 is complementarily switched at a duty ratio of 50%, and the second pair SW3, SW4 is also complementarily switched at a duty ratio of 50%. In the third mode φ3, the control circuit 350 sets the phase difference α between the first pair SW1, SW2 and the second pair SW3, SW4 to the maximum value α _MAX (ie, 180 °), and sets the switching frequency f to the first frequency f ₁ And the lowest frequency f ₀ (where f ₀ <f ₁ ), depending on the desired transmission power P _TX . For example, f ₀ = 110 kHz.

(Iv) Fourth mode φ4
In the fourth mode φ4, the inverter circuit 204 performs a half-bridge operation in the following manner. The first pair SW1 and SW2 are complementarily switched at the maximum switching frequency (the above-described second frequency f ₂ ), and the second pairs SW3 and SW4 are fixed with SW3 off and SW4 on. In a modification, SW3 may be turned off and SW4 may be turned on. The control circuit 350 changes the duty ratio d of the first pair SW1, SW2 between the maximum value _DMAX and the minimum value _DMIN according to the desired transmission power _PTX . The maximum value D _MAX is, for example, 50%. The minimum value D _MIN may be about 5%.

When the transmission power is controlled by switching the four modes of FIG. 3, the setting data D1 includes the frequencies f _{0 to} f ₂ shown in FIG. 3, the minimum value D _MIN of the duty ratio, the maximum value D _MAX , and the maximum of the phase difference. It can include at least one of a value α _MAX and a minimum value α _MIN .

  Note that the number of modes supported by the power transmission device 200 and the method of power control in each mode are not limited to this, and some modes may be omitted or another mode may be added.

6). As described above, in the power transfer phase, PID (proportional integral derivative) control for power stabilization is performed. The setting data D1 may include PID control constant values (P-term coefficient, I-term coefficient, D-term coefficient). As a result, the loop gain, responsiveness, viscosity, and responsiveness can be optimized according to the bus voltage V _ADP .

7). The setting data D1 may include a microprogram or firmware that defines the operation of the control parameter generation unit 306.

Priorities are assigned to the voltage value candidates (5, 9, 12, 19V) of the bus voltage V _ADP , and the memory 304 is a first list that defines a plurality of voltage value candidates and their respective priorities. 122 may be held. For example, in FIG. 2, the priority is higher in the order of 12V, 9V, 19V, and 5V.

  The negotiation unit 302 refers to the first list 222 and negotiates with the host / charge adapter 104 so that a voltage value having a high priority is selected. For example, the power supply efficiency can be increased by determining the priority order in descending order of the power supply efficiency of the power supply system 100. Alternatively, the priority order may be determined based on the stability of the power supply system 100, the accuracy of foreign object detection, and the like. In this case, the stability and the accuracy of foreign object detection can be increased.

The processor 300 may output an error signal when the host / charge adapter 104 does not support all candidates for the voltage value of the bus voltage V _BUS included in the first list 222. When receiving an error signal, the control circuit 350 does not supply power. This can prevent the power feeding system 100 from operating in an unstable state.

(Second Embodiment)
FIG. 4 is a block diagram of a power transmission device 200a according to the second embodiment. The power transmission device 200a further includes a DC / DC converter 230 in addition to the power transmission device 200 of FIG. DC / DC converter 230 receives bus voltage V _ADP and converts the voltage level. The DC / DC converter 230 may be a step-up converter, a step-down converter, or a step-up / step-down converter.

In the present embodiment, the first list 222 holds candidates for three voltage values 9V, 19V, and 5V. The DC / DC converter 230 converts the bus voltage V _ADP supplied from the host / charge adapter into the bus voltage V when the host / charge adapter (not shown) does not support all candidates of the voltage value of the bus voltage V _ADP. It is converted to one of _ADP candidates 5V, 9V, and 19V. The DC / DC converter 230 operates based on a control signal S6 from the processor 300a. The control signal S6 can include enable / disable switching of the DC / DC converter 230 and a set value (step-down ratio, step-up ratio) of the output voltage of the DC / DC converter 230.

For example, the memory 304 holds the second list 224 in addition to the first list 222. The second list 224 includes voltage value candidates (for example, 12V and 8V) of the bus voltage V _{ADP that} can be input to the DC / DC converter 230.

  The negotiation unit 302 generates a control signal S7 that instructs on / off of the load switch SW11. When the host / charge adapter supports the voltages (5V, 9V, 19V) included in the first list 222, the negotiation unit 302 turns on the load switch SW11 and disables the DC / DC converter 230. The negotiation unit 302 turns off the load switch SW11 and enables the DC / DC converter 230 when the host / charge adapter supports the voltages (8V, 12V) included in the second list 224.

For example, the DC / DC converter 230 is a step-down converter. When the host / charge adapter 104 supports the candidate 12V included in the second list 224, the processor 300a converts the 12V bus voltage V _ADP into the candidate 9V included in the first list 222 to the DC / DC converter 230. Let When the host / charge adapter 104 supports the candidate 8V included in the second list 224, the processor 300a converts the 8V bus voltage V _ADP into the candidate 5V included in the first list 222 to the DC / DC converter 230. Let

The second list 224 may define the priority order of voltage value candidates for the bus voltage V _ADP . If the negotiation fails for the candidates in the first list 222, the processor 300a negotiates the voltage value candidates included in the second list 224 according to the priority order.

According to the second embodiment, by providing the DC / DC converter 230, it is possible to cope with more voltage values of the bus voltage V _ADP than in the first embodiment.

  FIG. 5 is a diagram illustrating a charger 500 including the power transmission device 200. The charger 500 includes a housing 502 and a charging stand 504. The electronic device to be fed is placed on the charging stand 504. The inverter circuit 204, the control circuit 350, the processor 300 (300a), and the transmission antenna 201 are mounted on the circuit board 406. The transmission antenna 201 is laid out immediately below the charging stand 504. The housing 502 is provided with a receptacle 208. A plug of the host / charge adapter 104 is inserted into the receptacle 208.

  The embodiments are exemplifications, and it will be understood by those skilled in the art that various modifications can be made to combinations of the respective constituent elements and processing processes, and such modifications are within the scope of the present invention. . Hereinafter, such modifications will be described.

  In the embodiments, the Qi standard has been described. However, the present invention can also be applied to a standard derived from the Qi standard that will be formulated in the future or another standard.

  In the embodiment, the USB-PD standard has been described. However, the present invention can also be applied to a Quick Charge standard developed by Qualcom, the US-derived standard derived from the USB standard, or another standard. It is. When the power transmission device 200 supports a plurality of different standards, a receptacle may be provided for each standard.

  In the embodiment, the case where the processor 300 (processor 300a) and the control circuit 350 are configured as separate ICs has been described, but the present invention is not limited to this. For example, the control device may be configured by integrating the processor 300 and the control circuit 350 on one semiconductor substrate. Alternatively, the chip of the processor 300 and the chip of the control circuit 350 may be packaged to form a control module. Alternatively, the processor 300 and the control circuit 350 may be divided into more semiconductor chips, a part of the processor 300 may be integrated into the control circuit 350, or a part of the control circuit 350 may be integrated into the processor 300. May be.

  Although the present invention has been described using specific terms based on the embodiments, the embodiments only illustrate the principles and applications of the present invention, and the embodiments are defined in the claims. Many variations and modifications of the arrangement are permitted without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 100 ... Power feeding system, 102 ... Cable, 104 ... Host / charge adapter, 200 ... Power transmission device, 201 ... Transmission antenna, 202 ... Transmission coil, 203 ... Resonance capacitor, 204 ... Inverter circuit, 206 ... Processor, 208 ... Receptacle, 210 ... bus line, 212 ... internal bus, 220 ... memory, 222 ... first list, 224 ... second list, 230 ... DC / DC converter, 300 ... processor, 302 ... negotiation unit, 304 ... memory, 306 ... control parameter generation 308... Demodulator 350 350 control circuit 352 interface circuit 354 register 356 driver 360 control unit 400 power receiving device SW1 load switch

Claims (20)

A processor used in a wireless power transmitting device that transmits a power signal to a wireless power receiving device, comprising:
The wireless power transmission device
In addition to the processor,
A receptacle to which an external host / charge adapter is connected and receives the bus voltage;
A transmission antenna including a transmission coil;
An inverter circuit that receives the bus voltage and applies an alternating drive signal to the transmitting antenna;
A control circuit for controlling the inverter circuit;
With
The control circuit includes:
Registers,
A transmission control unit for controlling the inverter circuit based on a control parameter stored in the register;
With
The processor is
A negotiation unit that communicates with the host / charge adapter connected to the receptacle and determines a voltage value of a bus voltage;
A memory for holding a plurality of setting data corresponding to a plurality of candidates for the voltage value of the bus voltage;
A control parameter generation unit that generates the control parameter based on setting data corresponding to the voltage value of the bus voltage determined by the negotiation, and writes the control parameter;
A processor comprising:   The said setting data contain the threshold value used for the foreign material detection based on the comparison of Q value measured before the electric power feeding start, and Q value information received from the said wireless power receiving apparatus. The processor described.   The processor according to claim 1, wherein the setting data includes a threshold value used for foreign object detection by a power loss method.   The processor according to any one of claims 1 to 3, wherein the setting data includes at least one of a frequency and a duty ratio of an analog pin for detection of the wireless power receiving apparatus.   5. The processor according to claim 1, wherein the setting data includes at least one of a frequency and a duty ratio of a digital pin after detection by the wireless power receiving apparatus.   The processor according to any one of claims 1 to 5, wherein the setting data includes at least one variable range of a frequency, a duty ratio, and a phase in a power transfer phase.   The processor according to any one of claims 1 to 6, wherein the setting data includes a constant value for PID (proportional integral derivative) control for power stabilization in a power transfer phase. The inverter circuit includes an H bridge circuit,
The processor according to any one of claims 1 to 7, wherein the setting data includes a condition for switching between a half-bridge operation and a full-bridge operation of the inverter circuit.   The processor according to claim 1, wherein the setting data includes a microprogram or firmware that defines an operation of the control parameter generation unit. The memory further maintains a first list that defines a plurality of candidates for the voltage value of the bus voltage and respective priorities,
10. The processor according to claim 1, wherein the negotiation unit performs negotiation so that a voltage value having a high priority is selected. The processor outputs an error signal when the host / charge adapter does not support all candidates of voltage values of the bus voltage included in the first list;
The processor according to claim 10, wherein the control circuit does not supply power when receiving the error signal. The wireless power transmission device further includes a DC / DC converter that receives the bus voltage and converts a voltage level,
When the host / charge adapter does not support all candidates of the voltage value of the bus voltage, the DC / DC converter converts the bus voltage supplied from the host / charge adapter into one of the bus voltage candidates. The processor according to claim 1, wherein the conversion is performed.   The processor according to claim 12, wherein the memory further holds a second list that defines candidates of voltage values of the bus voltage that can be input to the DC / DC converter.   The processor according to any one of claims 1 to 13, wherein the control parameter includes at least one of information related to a switching frequency, a duty ratio, a phase, and foreign object detection of the inverter circuit.   The processor according to claim 1, wherein the wireless power transmission device conforms to a Qi standard.   The processor according to any one of claims 1 to 15, wherein the host / charge adapter conforms to a USB standard.   The processor according to claim 1, wherein the processor is integrated on a single semiconductor substrate.   The processor according to any one of claims 1 to 16, wherein a module is configured together with the control circuit. A wireless power transmitting device that transmits a power signal to a wireless power receiving device,
A receptacle to which an external host / charge adapter is connected and receives the bus voltage;
A transmission antenna including a transmission coil;
An inverter circuit that receives the bus voltage and applies an alternating drive signal to the transmitting antenna;
A control circuit for controlling the inverter circuit;
A processor according to any of claims 1 to 18;
A wireless power transmission apparatus comprising: A wireless power transmitting device that transmits a power signal to a wireless power receiving device,
A receptacle to which an external host / charge adapter is connected and receives the bus voltage;
A transmission antenna including a transmission coil;
An inverter circuit that receives the bus voltage and applies an alternating drive signal to the transmitting antenna;
Registers,
A transmission control unit for controlling the inverter circuit based on a control parameter stored in the register;
A negotiation unit that communicates with the host / charge adapter connected to the receptacle and determines a voltage value of a bus voltage;
A memory for holding a plurality of setting data corresponding to a plurality of candidates for the voltage value of the bus voltage;
A control parameter generation unit that generates the control parameter based on setting data corresponding to the voltage value of the bus voltage determined by the negotiation, and writes the control parameter;
A wireless power transmission apparatus comprising:

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