JP2016086472A - Dc power supply device and dc power supply method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform constant current control or constant voltage control in power supply to a load (secondary battery) without using a DC-DC converter.SOLUTION: High frequency AC power outputted from a high frequency power source 21 of a power transmission device 2 is wirelessly transmitted to a power reception device 3 by a power transmission part 23 and a power reception part 31 which are coupled in a magnetic field manner, and converted into DC power by a rectifying and smoothing circuit 32 and a battery 34 is charged therewith. A battery voltage Vand a charging current Iof the battery 34 are detected by a voltage/current detector 33 and fed back to a control part 24 by communication units 25 and 35. On the basis of the detected battery voltage Vand charging current I, the control part 24 calculates a control target value of output power in the constant current control and the constant voltage control and controls the output power of the high frequency power source 21 in such a manner that power to be supplied to a load becomes the control target value. At such a time, the high frequency power source 21 outputs the pulse-like high frequency AC power having a high level term and a low level term by the control part 24.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a DC power supply device and a DC power supply method that generate AC power, convert the AC power into DC power, and supply the AC power to a load.

  As a system for converting AC power into DC power and supplying the load to a load, a charging system that supplies DC power to the secondary battery in order to charge the secondary battery is known. Then, as a charging system for charging a secondary battery built in an electric vehicle, industrial equipment, portable electronic equipment, etc., the power transmission device and the power receiving device were magnetically coupled by a pair of coils, and generated by the power transmission device There is known a wireless charging system using a wireless power transmission technique in which AC power is transmitted to a power receiving apparatus by a pair of coils coupled with a magnetic field.

  In the wireless charging system, when the secondary battery built in the power receiving apparatus is a secondary battery charged by a constant current constant voltage charging method such as a lithium ion battery, for example, as shown in Patent Document 1, the power receiving apparatus A rectifier, a constant voltage controller, and a charger are installed inside, and after AC power is converted to DC power by the rectifier, the DC power is output to the charger at a predetermined constant voltage by the constant voltage controller, and is determined by the charger. A configuration in which a secondary battery is charged by a current constant voltage charging method is known. The constant current and constant voltage charging method starts charging the secondary battery at a constant current, and when the battery voltage of the secondary battery rises to a predetermined voltage, the secondary current is charged until the charging current drops to a predetermined current value at a constant voltage. In this method, the battery is charged.

  Conventionally, in general, a configuration in which a DC / DC converter is used and a secondary battery is charged by a constant current / constant voltage charging method by switching switching control of the DC / DC converter according to a charging state of the secondary battery is employed.

JP 2013-70581 A Japanese Patent No. 5431033

  In the conventional configuration, in order to control the charging of the secondary battery by constant current charging or constant voltage charging, a charging control device such as a DC / DC converter is provided in front of the secondary battery. There is a problem in that the circuit configuration after power conversion becomes complicated, which hinders downsizing and cost reduction of the charging device.

  In particular, in the wireless charging system, since a charging control device such as a DC / DC converter is provided on the power receiving device side, the power receiving device is increased in size and cost. In particular, for small devices such as mobile phones and portable terminals, such an increase in size and cost is an important issue in recent years when there is a need to reduce the size and cost of the charging system.

  The above problem applies not only to the charging system, but also to a DC power supply device that converts AC power to DC power and then supplies the DC power to the load by constant current control or constant voltage control. is there.

  The present invention has been made in view of the above-described problems, and the DC power can be generated by a constant current method or a constant voltage method without providing a control device for controlling the supply of DC power such as a DC / DC converter before the load. It is an object to provide a DC power supply device and a DC power supply method capable of controlling supply.

  The direct-current power supply apparatus provided by the first aspect of the present invention includes a power generation unit that has a high-frequency inverter and outputs high-frequency AC power, and converts the high-frequency AC power into DC power and supplies the load to a load. Conversion means; detection means for detecting an electrical physical quantity relating to DC power supplied to the load; and generating a pulse signal having a frequency lower than the frequency of the high-frequency AC power, and based on the generated pulse signal, The high-frequency AC power output from the power generation means includes a first period in which the high-frequency AC power is in an on state or a first level, and a second period in which the high-frequency AC power is in an off state or a second level lower than the first level. A pulse-like high-frequency AC power that alternately repeats the period at the frequency of the pulse signal, and the physical quantity detected by the detection means is a predetermined target value As will, by adjusting the waveform of the pulse signal, and a control means for controlling said power generating means.

  Preferably, the control unit adjusts a pulse width of the pulse signal based on a difference between the physical quantity detected by the detection unit and the target value.

  Preferably, the control unit calculates a difference between the physical quantity detected by the detection unit and the target value, generates a difference signal indicating the difference information, and a carrier signal for generating a carrier signal Generating means, comparing means for comparing the difference signal and the carrier signal and generating the pulse signal based on the comparison result; and a first period during which the high-frequency signal is turned on or at a high level based on the pulse signal; High-frequency signal generating means for generating a pulse-shaped high-frequency signal that alternately repeats the second period in which the high-frequency signal is off or at a low level at the frequency of the pulse signal, and the power generating means The high frequency inverter is controlled according to the pulsed high frequency signal, and the pulsed high frequency AC power is output.

  Alternatively, the control means calculates a difference between the physical quantity detected by the detection means and the target value, generates a difference signal indicating the difference information, and generates a carrier signal to generate a carrier signal. A comparison means for comparing the difference signal and the carrier signal and generating the pulse signal based on the comparison result; a high-frequency signal generation means for generating a high-frequency signal; a high-frequency signal by the high-frequency signal generation means; The first period in which the high-frequency signal is turned on or at a high level and the second period in which the high-frequency signal is turned off or at a low level are alternately multiplied by the frequency of the pulse signal. And a multiplying means for generating a pulsed high-frequency signal that repeats, and the power generating means According high frequency signal, and controls the high-frequency inverter, and outputs the pulsed high-frequency AC power.

  Preferably, the comparing means is an on voltage or the high level voltage when the difference signal is larger than the carrier signal, while an off voltage or the low level voltage when the difference signal is equal to or less than the carrier signal. A pulse signal that is a voltage is generated.

  On the other hand, the control means makes the on-voltage period of the pulse signal constant, and adjusts the off-voltage period of the pulse signal based on the difference between the physical quantity detected by the detecting means and the target value. May be.

  Preferably, the physical quantity detected by the detection means is an average value of the pulse signal for each predetermined period, and the physical quantity detected by the detection means is at least one of DC current, DC voltage, or DC power. One.

  Further, the impedance is provided between the power generation means and the power conversion means, and adjusts the impedance viewed from the output end to the load side so that the reflected wave power at the output end of the power generation means is a predetermined value or less. Impedance adjusting means is provided.

  In addition, a pair of coils magnetically coupled to each other is provided between the impedance adjustment unit and the power conversion unit, and the AC power output from the power generation unit is contactlessly transmitted through the pair of coils. It is transmitted to the conversion means.

  Preferably, the load is a secondary battery or an accumulator.

  A DC power supply method provided by the second aspect of the present invention includes a first step of operating a high-frequency inverter to output high-frequency AC power, and converting the high-frequency AC power into DC power and supplying the load to a load. Two steps, a third step of detecting an electrical physical quantity related to the DC power supplied to the load, a pulse signal having a frequency lower than the frequency of the high-frequency AC power is generated, and based on the generated pulse signal, The high-frequency AC power output by the first step includes a first period in which the high-frequency AC power is in an on state or a first level, and a second period in which the high-frequency AC power is in an off state or a second level lower than the first level. The period is changed to pulsed high-frequency AC power that alternately repeats at the frequency of the pulse signal, and the physical quantity detected by the third step becomes a predetermined target value. , By adjusting the waveform of the pulse signal, and a fourth step of controlling the high frequency AC power output by the first step.

  According to the DC power supply device and the DC power supply method according to the present invention, the high-frequency AC power output from the power generation means is turned off when the high-frequency AC power is in the on state or the first level and the high-frequency AC power is off. A pulse-like high-frequency AC power having a state or a second period that is at the second level, and an electrical physical quantity (DC voltage or DC current) related to DC power supplied to the load is a predetermined value (in the case of constant current control) Since the length of the first period and the second period of the pulsed high-frequency power is controlled so as to be constant current value or constant voltage value in the case of constant voltage control, the power conversion means and the load In addition, for example, it is not necessary to provide means (such as a constant current control means or a constant voltage control means) for controlling the electrical physical quantity supplied to the load such as a DC / DC converter to a predetermined value. Accordingly, the configuration of the DC power supply device can be simplified and the cost can be reduced.

It is a block diagram which shows the structural example of the charging device (DC power supply device) which concerns on embodiment of this invention. It is a circuit diagram which shows the structural example of a high frequency inverter circuit (half-bridge type). It is a figure which shows the charge characteristic of a lithium ion battery. It is a block diagram which shows the structure of the control part which controls the output power of the high frequency power supply which concerns on embodiment of this invention. It is a flowchart which shows the electric power output control process of the high frequency power supply which the control part which concerns on embodiment of this invention performs. It is a figure which shows the waveform of each output signal of the control part which concerns on embodiment of this invention. It is a figure which shows the waveform of each output signal of a control part accompanying the change of control signal S (DELTA) _{P which} concerns on embodiment of this invention. It is a block diagram which shows the structure of the control part which controls the output electric power of the high frequency power supply which concerns on the modification of embodiment of this invention. It is a flowchart which shows the electric power output control process of the high frequency power source which the control part which concerns on the modification of embodiment of this invention performs. It is a figure which shows the waveform of each output signal of the control part which concerns on embodiment modification of this invention. It is a block diagram which shows the structure of the modification of the charging device (DC power supply device) which concerns on this invention. It is a circuit diagram which shows the structural example of the modification 1 (half-bridge type) of the high frequency power supply which concerns on this invention. It is a circuit diagram which shows the structural example of the modification 2 (full bridge type) of the high frequency power supply which concerns on this invention.

  As an embodiment of a DC power supply device according to the present invention, a charging device for charging a secondary battery built in an electric vehicle or the like will be described as an example. FIG. 1 is a block diagram illustrating a configuration example of the entire charging apparatus according to the present invention.

  The charging device shown in FIG. 1 is configured to charge a secondary battery 34 (rechargeable battery; hereinafter referred to as a battery 34) in the power receiving device 3 using the non-contact power transmission system 1. The non-contact power transmission system 1 is a system that non-contactly transmits high-frequency AC power of several MHz to several hundred MHz from the power transmission device 2 to the power reception device 3 by a magnetic resonance method. In this embodiment, a system that transmits 13.56 MHz high-frequency AC power in a non-contact manner will be described as an example. In the block configuration of FIG. 1, the portion excluding the battery 34 is the configuration of the charging device. As the non-contact power transmission system 1 that charges the battery 34 in a non-contact manner, a charging system that charges a battery mounted on an electric vehicle is well known. In the following description, an electric vehicle charging system will be described as an example.

  The power transmission device 2 includes a high frequency power source 21, an impedance matching unit 22, a power transmission unit 23, a control unit 24, and a communication unit 25. The power reception device 3 includes a power reception unit 31, a rectifying / smoothing circuit 32, a voltage / current detector 33, A battery 34 and a communication unit 35 are included.

The high-frequency power source 21 performs full-wave rectification on commercial power (AC power) input from a commercial power source and converts it into DC power, and a high-frequency power that converts DC power input from the rectifier circuit 211 into high-frequency AC power. The inverter circuit 212 and a power detector 213 that detects the traveling wave power P _f and the reflected wave power P _r at the output terminal A of the high-frequency power source 21 are configured. The high-frequency inverter circuit 212 receives the drive signal S _d from the control unit 24, turns on and off the built-in switching element based on the drive signal S _d, and turns on the high-frequency AC power at a predetermined frequency (13.56 MHz). Pulsed high-frequency AC power having a high level period and a low-level period in which the high-frequency AC power is turned off is generated. The high frequency inverter circuit 212 has a high level period in which the amplitude of the high frequency AC power at a predetermined frequency (13.56 MHz) is the first level, and a low level in which the amplitude of the high frequency AC power is the second level lower than the first level. A pulsed high-frequency AC power having a period may be generated. (In the claims, "first period" corresponds to the high level period, and "second period" corresponds to the low level period.)

The rectifier circuit 211 is a block that generates input power P _CC (DC voltage V _CC ) to the high-frequency inverter circuit 212 from AC power input from a commercial power source. The rectifier circuit 211, for example, full-wave rectifies a commercial voltage (for example, AC100 [V]) input from a commercial power supply with a rectifier circuit in which four semiconductor rectifier elements are bridge-connected, and the level after rectification is a smoothing circuit. It is constituted by a known power supply circuit that generates a DC voltage V _CC by smoothing. In the embodiment of the present invention, the rectifier circuit 211 may not include a smoothing circuit.

High-frequency inverter circuit 212, a DC power input from the rectifier circuit 211, based on the drive signal S _d supplied from the control unit 24, into a pulsed high-frequency AC power and a high-level period and low level period Output block. The DC input portion of the high frequency inverter circuit 212 includes a capacitor that supplies a high frequency current.

The high-frequency inverter circuit 212 is configured by, for example, a half-bridge type switching amplifier shown in FIG. Drive switching amplifier shown in the figure, the input pair of power terminals b, a switching circuit connected a series circuit of two identical types of semiconductor switching elements Q _B between b ', the drive signal to the switching circuit The circuit includes an output circuit that outputs high-frequency AC power output from the switching circuit to the outside.

The drive circuit is composed of a transformer T1 in which two secondary windings wound in opposite directions are coupled to a primary winding. A drive signal S _d (also referred to as an output control signal S _d ) output from the control unit 24 is input to the primary winding of the transformer T1, and one secondary winding of the transformer T1 (the upper winding in FIG. 2). ) drive signal S _d and the phase of the RF signal v from the 'is output, the other secondary winding of the transformer T1 (winding of the bottom in FIG. 2 side) drive signal S _d and the reverse-phase high frequency signal -v from' Is output.

The output circuit includes a filter circuit in which a resonance circuit in which a capacitor C ₁ and an inductor are connected in series, and an impedance conversion circuit in which the inductor and the capacitor C ₂ are connected in an L shape, and an insulating transformer T 2. The inductor L _{1 in} FIG. 2 serves both as an inductor for the resonance circuit and an inductor for the impedance conversion circuit. The filter circuit removes a DC component and an unnecessary high-frequency component (noise component) from the high-frequency AC power pulsed from the switching circuit. The high-frequency AC power output from the filter circuit is input to the primary winding of the transformer T2. The high-frequency AC power P _out (high-frequency AC voltage V _out ) output as a pulse from the secondary winding of the transformer T 2 is output to the impedance matching unit 22.

N-channel MOSFETs are used for the pair of semiconductor switching elements Q _B , but other types of transistors such as bipolar transistors can be used. Further, the pair of semiconductor switching elements Q _B may be a complementary type in which an N channel type and a P channel type are combined. In this case, only one secondary winding of the transformer T1 may be used, and the pulse output of the high-frequency voltage v ′ may be input to the gates of the N-channel MOSFET and the P-channel MOSFET, respectively. In the present embodiment, the high-frequency inverter circuit 212 is configured by a half-bridge type switching amplifier, but may be configured by a full-bridge type or push-pull type switching amplifier. In this embodiment, the transformer T1 is used in the drive circuit. However, when driving with a rectangular wave signal, a digital isolator may be used.

Assuming that the drive signal S _d is S _d = V · sin (2πf · t + φ) (f: fundamental frequency, φ: initial phase), in the period when the drive signal S _d is input to the primary winding of the transformer T1, the transformer An in-phase high-frequency voltage v ′ = V ′ · sin (2πf · t + φ) is output from one secondary winding of T1, and an anti-phase high-frequency voltage −v ′ = − V is output from the other secondary winding of the transformer T1. '· Sin (2πf · t + φ) is output. Phase high frequency voltage v 'is input to one of the semiconductor switching element Q _B (the semiconductor switching element Q _B of the upper in FIG. 2), a high frequency voltage -v reverse phase' of the other semiconductor switching element Q _B (FIG. 2 is input to the lower semiconductor switching element Q _B ). Since the two semiconductor switching elements Q _B are N-channel MOSFETs, one semiconductor switching element Q _B is turned on when the high-frequency voltage v ′ is at a high level, and the other semiconductor switching element Q _B is The on-operation is performed when the high-frequency voltage −v ′ is at a high level. Accordingly, the two semiconductor switching elements Q _B repeat the on / off operation alternately every half cycle of the high-frequency voltage v ′.

The two semiconductor switching elements Q _B alternately repeat the on / off operation, so that the voltage V _{a at} the connection point “a” becomes “V _CC ” in the period of v ′> 0 and becomes zero level in the period of v ′ ≦ 0. Changes to a rectangular wave. The direct current component and the switching noise are removed from the rectangular wave output by the filter circuit of the output circuit, and the high frequency alternating voltage _Vout is output from the output terminals c and c ′ via the insulating transformer T2.

Power detector 213, which detects the forward power P _f and the reflected wave power P _r of the high-frequency AC power output from the high-frequency inverter circuit 212, for example, a bidirectional coupler, the two-way coupling A pair of voltmeters that detect the traveling wave detection signal V _f and the reflected wave detection signal V _r output from the detector, and the traveling wave detection signal V _f and the reflected wave detection signal V _r are converted into the traveling wave power P _f and the reflected wave, respectively. composed of a converter for converting the power P _r. The traveling wave power P _f and the reflected wave power P _r detected by the power detector 213 are input to the control unit 24.

The impedance matching unit 22 is connected to the load side from the output terminal A of the high frequency power source 21 in order to suppress the amount of reflected wave output from the high frequency power source 21 (reflected wave power P _r ) reflected at the input part of the impedance matching unit 22. The impedance Z _A (hereinafter referred to as “load-side impedance Z _A ”) is adjusted. The impedance matching unit 22 includes, for example, a π-type circuit in which a first capacitor (not shown), an inductor (not shown), and a second capacitor (not shown) are connected in π-type. The high frequency power source 21 is designed to output high frequency AC power with optimum transmission efficiency when a load having a characteristic impedance Z _o (for example, 50 [Ω]) is connected. Control unit 24, the load-side impedance Z _A is a characteristic impedance Z _O, as come reflected power P _r for returning to the high frequency power source 21 is reduced, to control the impedance matching device 22. For example, the control unit 24, while monitoring the reflected wave power P _r inputted from the power detector 213, first changes the inductance of each capacitor and inductor of the second capacitor, the reflected wave power P _r is a predetermined Set to a value that is less than or equal to the value. The impedance matching unit 22 may be configured by an L-type circuit, an inverted L-type circuit, a T-type circuit, or the like in addition to the π-type circuit. The impedance matching unit 22 may change the impedance by using a transformer including a ferrite core, a primary winding, and a secondary winding and changing the turn ratio.

The power transmission unit 23 wirelessly transmits the high-frequency AC power output from the impedance matching unit 22 to the power reception unit 31 of the power reception device 3. The power transmission unit 23 includes, for example, a series resonance circuit including an inductor 231 formed of a circular coil having a plurality of turns and a capacitor 232 connected in series to the inductor 231. In the power transmission unit 23, the series resonance frequency f _o (= 1 / [2π · √ (L · C)]) (L: self-inductance of the inductor 231, C: capacitance of the capacitor 232) of the series resonance circuit is from the high-frequency power source 21. The frequency f _g (hereinafter referred to as power supply frequency f _g ) [MHz] of the output high-frequency AC power is adjusted.

The control unit 24 includes a microcomputer including a ROM, a RAM, a CPU, an FPGA (Field-Programmable Gate Array), an ASIC (Application Specific Integrated Circuit), and the like. The control unit 24 controls the high-frequency inverter circuit 212 of the high-frequency power source 21 so that a current value (DC current) / voltage value (DC voltage) input from a voltage / current detector 33 described later becomes a set current or a set voltage. A drive signal _Sd is output to control the high-frequency AC power output from the high-frequency power source 21.

  In the present embodiment, the battery 34 is a lithium ion battery generally mounted on an electric vehicle. Lithium-ion batteries start charging at a constant current, and when the battery voltage rises to a predetermined voltage, the battery is switched to a constant voltage and charged until the charging current changes to a predetermined current. Next battery. The control unit 24 realizes constant current charging control and constant voltage charging control in the charging process of the battery 34 by a constant current constant voltage charging method by controlling high frequency AC power (output power) output from the high frequency power supply 21. Details of the control unit 24 will be described later.

The communication unit 25 performs wireless communication with a communication unit 35 provided in the power receiving device 3, and the charging current I _j of the battery 34 and the battery voltage V _j detected by the voltage / current detector 33 from the power receiving device 3. Receive detection data. The communication unit 25 includes a reception circuit, a frequency conversion circuit, and a demodulation circuit. The reception circuit receives a wireless communication signal transmitted from the communication unit 35, and the frequency conversion circuit sets the frequency of the wireless communication signal to a predetermined low frequency. After the conversion, the demodulating circuit demodulates the detection data of the charging current I _j and the battery voltage V _j . The detection data of the charging current I _j and the battery voltage V _j received by the communication unit 25 are input to the control unit 24.

The power receiving unit 31 performs magnetic field coupling with the power transmission unit 23 of the power transmission device 2 and receives pulsed high-frequency AC power from the power transmission unit 23. The power reception unit 31 has the same configuration as that of the power transmission unit 23, and includes a series resonance circuit including an inductor 311 formed of a circular coil having a plurality of turns and a capacitor 312 connected in series to the inductor 311. The power receiving unit 31 also has a series resonance frequency f _o (= 1 / [2π · √ (L · C)]) (L: self-inductance of the inductor 311 and C: capacitance of the capacitor 312) of the power supply frequency f _g. It is adjusted to [MHz].

  The rectifying / smoothing circuit 32 rectifies and smoothes the high-frequency alternating current output from the power receiving unit 31. The rectifying / smoothing circuit 32 includes, for example, a rectifying circuit unit in which four rectifying elements are configured as a bridge circuit, and a smoothing circuit unit using a capacitor. When the frequency output from the power transmission unit 23 is in the HF band, short key barrier diodes are used for the four rectifying elements. In the rectifier element, a capacitor is formed in parallel inside the element, and in the HF band, a high-frequency current of a leading phase flows through the capacitor. Therefore, in order to cancel the high-frequency current of the leading phase, Inductors may be connected in parallel, or inductors may be connected in series.

The voltage / current detector 33 includes a DC voltmeter and a DC ammeter, measures a DC voltage (battery voltage) V _j applied to the battery 34 from the rectifying / smoothing circuit 32 with the DC voltmeter, and rectifies and smoothes with the DC ammeter. DC current (charging current) _j supplied from 32 to the battery 34 is measured. The battery voltage V _j and the charging current I _j detected by the voltage / current detector 33 are input to the control unit 24 of the power transmission device 2 via the communication units 35 and 25. The battery voltage V _j and the charging current I _j detected by the voltage / current detector 33 are measured by an average value for each predetermined period (for example, one period) of a carrier signal set in a carrier condition setting unit 24H described later. Or may be a predetermined period of the carrier signal S _FL outputted from the carrier signal generating unit 24I, it may be a predetermined period of OFF signal S _ON-OFF output from the comparison unit 24J. Further, based on the pulsed high-frequency AC power output from the power transmission device 2, one high level period and one low level period may be set as one period, and the average value may be measured for each predetermined period.

  The battery 34 is a secondary battery that can be repeatedly used as a battery by charging, and includes, for example, a nickel metal hydride battery, a nickel cadmium battery, a lithium ion battery, and the like. In addition, a lead storage battery may be used. In the present embodiment, an example of a lithium ion battery having the charging characteristics shown in FIG. 3 will be described.

The communication unit 35 performs wireless communication with the communication unit 25 provided in the power transmission device 2 to transmit the detection data of the charging current I _j of the battery 34 and the battery voltage V _j detected by the voltage / current detector 33. Transmit to device 2. The communication unit 35 includes a modulation signal generation circuit, a carrier generation circuit, a modulation circuit, and a transmission circuit. The modulation signal generation circuit generates a modulation signal including information on the charging current I _j and the battery voltage V _j , and the carrier generation circuit The generated carrier signal is modulated by a modulation circuit by a predetermined modulation method to generate a communication signal, the transmission circuit amplifies the communication signal, and then radiates into the air via an antenna (transmits to the communication unit 25) ).

  Next, output control of the high-frequency AC power output from the high-frequency power source 21 by feedback control of the control unit 24 according to the present embodiment will be described. FIG. 4 is a block diagram illustrating a configuration of a control system that controls the output power of the high-frequency power source 21 of the control unit 24. As shown in FIG. 4, the control unit 24 includes three adders 24A, 24B, and 24F, three error amplification units 24C, 24D, and 24G, a control switching unit 24E, a carrier condition setting unit 24H, The carrier signal generation unit 24I, the comparison unit 24J, the high frequency condition setting unit 24K, the high frequency signal generation unit 24L, the drive signal generation unit 24M, and the output stop control unit 24N are configured.

In this embodiment, since both the constant current charging and the constant voltage charging of the battery 34 are controlled by controlling the output power of the high frequency power source 21, the control unit 24 outputs the output control signal S based on the constant current charging control. A processing circuit for generating _d and a processing circuit for generating the output control signal S _d based on constant voltage charging control are provided. Adders 24A and error amplifying section 24C based on the constant-voltage charging control, a processing circuit for generating an output control signal S _d, the adder 24B and the error amplifying section 24D, based on the constant-current charging control, the output a processing circuit for generating a control signal S _d.

The battery 34 is a lithium ion battery that can be serially paralleled according to the voltage and capacity to be used. In general, as shown in FIG. 3, the lithium ion battery is subjected to constant current charging control from the start of charging until the battery voltage V _{j of the} battery 34 rises to a predetermined voltage V _th , and the battery voltage V _j is set to the voltage V After rising to _th , constant voltage charging control is performed until the charging current I _j drops to the minimum charging current I _jmin . In the control unit 24, a constant current value I _cj in constant current charge control of the battery 34, a constant voltage value V _cj in constant voltage charge control, a minimum charge current I _jmin, and a voltage V _th are set by the user.

The adder 24A calculates a difference voltage ΔV _j (= V _cj −V _j ) between the constant voltage value V _cj in the constant voltage charging control and the battery voltage V _j detected by the voltage / current detector 33, and an error amplifying unit 24C performs a process of generating a control target value P _CV of the output power of the high-frequency power source 21 by multiplying the difference voltage ΔV _j by a predetermined feedback gain. The adder 24B calculates a difference current ΔI _j (= I _cj −I _j ) between the constant current value I _cj in the constant current charging control and the charging current I _j detected by the voltage / current detector 33, and an error amplifying unit 24D performs a process of generating a control target value _PCI for the output power of the high-frequency power source 21 by multiplying the difference current ΔI _j by a predetermined feedback gain.

The control switching unit 24E performs processing for switching between constant voltage charging control and constant current charging control. Specifically, control is performed to switch between the control target value P _CV based on the difference voltage ΔV _j and the control target value P _CI based on the difference current ΔI _j output to the adder 24F. The control switching unit 24E includes a voltage V _th (a threshold value of the battery voltage V _j for switching the constant current charging control to the constant voltage charging control) set by the user, and the battery voltage V _j detected by the voltage / current detector 33. The control switching unit 24E compares the battery voltage V _j and the voltage V _th and, if V _j <V _th , outputs the control target value P _CI based on the difference current ΔI _j to the adder 24F, If V _j ≧ V _th , the control target value P _CV based on the differential voltage ΔV _j is output to the adder 24F.

Adder 24F and the error amplifying section 24G on the basis of the difference between the power [Delta] P _f of the control target value P _CV or control target value P _CI and forward power P _f detected by the power detector 213, a control signal Esuderuta _P A processing circuit to be generated. The adder 24F receives the traveling wave power P _f detected by the power detector 213, and the adder 24F receives the traveling wave power P _f and the control target value P _CV input from the control switching unit 24E or the control. The power difference ΔP _f (= P _CV −P _f or P _CI −P _f ) with _respect to the target value P _CI is calculated. Then, the error amplification unit 24G outputs the comparison unit 24J described later control signals Esuderuta _P multiplied by the predetermined feedback gain to the difference power [Delta] P _f.

Carrier condition setting unit 24H, the frequency f _p of the carrier signal S _FL generated by a predetermined program, parameters such as amplitude A, set the carrier signal generating unit 24I. Frequency f _p is set, for example, is a low frequency of hundredths 1-1000 parts per relative frequency f (13.56 MHz) of the RF voltage V _o that is set to the high frequency condition setting unit 24K that will be described later. The parameters such as the frequency f _p and the amplitude A of the carrier signal S _FL may be changed by the user.

Carrier signal generating unit 24I, the frequency f _p set in the carrier condition setting unit 24H, based on parameters such as the amplitude A, to generate a sawtooth shape (saw-type) or triangular carrier signal S _FL, comparing section 24J Output to. Hereinafter, description will be given using a saw-shaped carrier signal _SFL .

Comparing unit 24J compares the carrier signal S _FL input from the control signal Esuderuta _P and the carrier signal generating unit 24I input from error amplification part 24G, the high-frequency signal in the later-described high-frequency signal generator 24L generating A pulse signal (hereinafter referred to as an on / off signal) S _ON-OFF is generated and output. Specifically, the comparing unit 24J compares the carrier signal S _FL saw type input from the control signal Esuderuta _P and the carrier signal generating unit 24I input from error amplification part 24G, the control signal Esuderuta _P carrier signal as an on-voltage when a larger S _FL, whereas the control signal Esuderuta _P is such that the off-voltage when the following carrier signal S _FL, generates an on-off signal S _oN-oFF. Therefore, on-off signal S _ON-OFF output from the comparison unit 24J according to a control signal Esuderuta _P from the error amplifying section 24G, a pulse width (or duty ratio) is adjusted.

The high frequency condition setting unit 24K sets parameters such as the frequency f (13.56 MHz) and the initial phase φ of the high frequency voltage V _o generated by a preset program in the high frequency signal generation unit 24L. Note that parameters such as the frequency f and the initial phase φ of the high-frequency voltage V _o may be changeable by the user.

The high frequency signal generation unit 24L is configured so that the high frequency signal is on or the amplitude of the high frequency signal is based on the frequency f and the initial phase φ input from the high frequency condition setting unit 24K and the on / off signal S _ON-OFF input from the comparison unit 24J. A high-frequency period in which the high-frequency signal is turned off and a low-frequency period in which the high-frequency signal is in the off state or the low-frequency period in which the amplitude of the high-frequency signal is lower than the high level are alternately repeated at the on _- off signal S _ON-OFF A signal S _FH is generated. Specifically, when the _{ON / OFF} signal S _ON-OFF input from the comparison unit 24J is an ON voltage, it is expressed by, for example, A _n · sin (2πf · t + φ) (A _n : predetermined amplitude) by a direct digital synthesizer. The sine wave high frequency voltage V _o (high frequency signal S _F ) is generated, and when the on / off signal S _ON-OFF is the off voltage, the high frequency voltage V _o is not generated. As a result, a pulsed high-frequency signal S _FH having a high level period in which the high-frequency signal is in an on state and a low level period in which the high-frequency signal is in an off state is generated (FIG. 6C described later). Then, the high frequency signal generation unit 24L outputs the generated pulsed high frequency signal S _FH to the drive signal generation unit 24M.

Alternatively, when the on / off signal S _ON-OFF input from the comparison unit 24J is an on voltage, the direct digital synthesizer expresses a sine represented by A ₁ · sin (2πf · t + φ) (A ₁ : high level amplitude). When a high frequency voltage V _o (high frequency signal S _F ) is generated and the on / off signal S _ON-OFF is an off voltage, A ₂ · sin (2πf · t + φ) (A ₂ : low level amplitude; 0 ≦ A ₂ A sine wave high-frequency voltage V _o (high-frequency signal S _F ) represented by <A ₁ ) is generated. As a result, a pulsed high-frequency signal S _FH having a high-level period in which the amplitude of the high-frequency signal is high and a low-level period in which the amplitude of the high-frequency signal is low is generated. In the following description of the present embodiment, an example will be described in which the high-frequency signal generation unit 24L generates a pulsed high-frequency signal _SFH having a high level period in an on state and a low level period in an off state.

Drive signal generation unit 24M, based on the pulsed high-frequency signal S _FH inputted by the high-frequency signal generation unit 24L, the drive signal (output control signal) for driving the drive circuit of the high-frequency inverter circuit 212 to generate S _d And output to the drive circuit of the high-frequency inverter circuit 212.

The output stop control unit 24N performs a process of stopping the power output of the high-frequency power source 21 (stopping the charging of the battery 34). When the charging current I _j of the battery 34 is reduced to the minimum charging current I _jmin by the constant voltage charging control, the output stop control unit 24N considers that the charging is completed and stops the power output of the high frequency power source 21. Further, even if the detected value of the reflected power P _r by the power detector 213 is greater than P _rth set in advance by the user, or an increase in loss of the high frequency power source 21 by the reflected wave power, high-frequency power source 21 and the impedance matching device The reactive power between the high frequency power supply 21 and the high frequency power supply 21 is stopped.

The output stop control unit 24N includes a threshold value P _rth and a minimum charging current I _{jmin of} the reflected wave power set by the user, a detection value of the charging current I _j by the voltage / current detector 33, and a reflection by the power detector 213. A detection value of the wave power _Pr is input. Output stop control unit 24N compares the detection value and the threshold value P _rth of the reflected wave power P _r, if P _rth <P _r, and outputs an output stop signal S _stop error amplifying section 24C, to 24D. The output stop control unit 24N compares the detected value of the charging current I _j with the minimum charging current I _jmin , and outputs an output stop signal S _stop to the error amplification units 24C and 24D when I _j ≦ I _jmin . When the output stop signal S _stop is input, the error amplification units 24C and 24D set the output power control target values P _CV and P _CI to zero. As a result, the output control signal S _d for making the output power from the high frequency power supply 21 zero is output to the high frequency power supply 21, so that the output power of the high frequency power supply 21 is controlled to be zero.

Next, power output control processing of the high frequency power supply 21 performed by the control unit 24 according to the present embodiment will be described with reference to FIGS. 5 and 6. In the following description, since the remaining capacity of the battery 34 becomes “requires charging”, the electric vehicle is parked at a predetermined charging position and is controlled based on the power supply request output from the power receiving device 3 to the power transmitting device 2. The case where 24 controls the output of the high frequency power supply 21 will be described. Note that the power supply request output from the power receiving device 3 to the power transmitting device 2 is performed by wireless communication by the communication units 35 and 25, for example. Further, the control unit 24 based on the detection value of the reflected power P _r from the power detector 213, performs the impedance adjustment and the output stop processing of the impedance matching device 22, the details of these processes will be omitted.

When the power output from the high frequency power supply 21 is started by the power supply request output from the power receiving device 3 to the power transmitting device 2 described above, the control unit 24 detects the battery voltage V _j detected by the voltage / current detector 33. And the charging current I _j are read via the communication units 35 and 25 (step S101). Here, when the voltage / current detector 33 detects the battery voltage V _j and the charging current I _j , the cycle of the carrier signal S _FL generated by the carrier signal generator 24I or the on / off signal S output from the comparator 24J. _These values are detected by the average value for each _ON-OFF cycle. Then, the control unit 24 determines whether the battery voltage V _j is a preset voltage V _th or more (step S103). If V _j <V _th (step S103; NO), the control unit 24 proceeds to step S107 and performs constant current charging control. On the other hand, if V _j ≧ V _th (step S103; YES), the charging current I _j detected by the voltage / current detector 33 is compared with the _preset minimum charging current I _jmin (step S105). _{If j} > I _jmin (step S105; YES), the process proceeds to step S111 to perform constant voltage charging control.

Normally, if the battery 34 is not fully charged, V _j <V _th is obtained in the process of the first step S103 after the start of the output control. Therefore, the control unit 24 proceeds to step S107 and is initially charged with a constant current. The control controls the supply of high-frequency AC power to the power receiving device 3 (the battery 34 is charged by constant current control), and the battery voltage V _j rises to the threshold value V _th by this constant current charge control (step S103; YES). Then, switching to constant voltage charging control is performed to control the supply of high-frequency AC power to the power receiving device 3 (charging the battery 34 with constant voltage control).

In the constant current charging control, the control unit 24 calculates a difference current ΔI _j (= I _cj −I _j ) between the preset constant current I _cj and the charging current I _j detected by the voltage / current detector 33. (Step S107), the control target value _PCI is generated by multiplying the difference current ΔI _j by a predetermined feedback gain (Step S109). Thereafter, a difference power ΔP _f (= P _CI −P _f ) between the control target value P _CI and the traveling wave power P _f detected by the power detector 213 is calculated, and the error amplifying unit 24G calculates the difference. The control signal SΔ _P (broken line in FIG. 6A) is generated by multiplying the power ΔP _f by a predetermined feedback gain (step S115). Then, the error amplification unit 24G outputs the generated control signal Esuderuta _P to the comparison unit 24J. At this time, the carrier signal generator 24I generates a sawtooth carrier signal S _FL (solid line in FIG. 6A) that satisfies the carrier condition set in the carrier condition setting unit 24H, and outputs it to the comparator 24J.

Subsequently, the comparing unit 24J compares the carrier signal S _FL of a predetermined frequency, off signal S _ON-OFF as a result of the comparison (Figure from the control signal Esuderuta _P and a carrier signal generator 24I from the error amplifying section 24G 6 (b)) is generated and output to the high-frequency signal generator 24L (step S117). Specifically, the comparing unit 24J is the when the control signal Esuderuta _P is greater than the carrier signal S _FL (T1), so that the on-voltage, whereas the control signal Esuderuta when _P is less than the carrier signal S _FL ( At T2), an on / off signal S _ON-OFF is generated so that the off voltage is obtained.

The high frequency signal generator 24L generates a high frequency signal of a high frequency condition set in the high frequency condition setting unit 24K when the input on / off signal S _ON-OFF is an on voltage, and the on / off signal S _ON-OFF is turned off. Do not generate high frequency signals when voltage. As a result, the high-frequency signal generator 24L repeats a high-frequency period in which the high-frequency signal is turned on and a low-level period in which the high-frequency signal is turned off alternately at the frequency of the on / off signal S _ON-OFF. S _FH (FIG. 6C) is generated and output to the drive signal generator 24M (step S119).

The drive signal generator 24M generates a drive signal S _d (same waveform as in FIG. 6C) for driving the drive circuit based on the pulsed high frequency signal S _FH output from the high frequency signal generator 24L. Generated and output to the drive circuit of the high-frequency inverter circuit 212 (step S121). High-frequency inverter circuit 212, based on this drive signal S _d, to operate the drive circuit to generate a pulsed high-frequency AC power and supplies the power receiving device 3. High-frequency AC power output from the high-frequency inverter circuit 212, it is equal to the forward power P _f, the power to the power receiving device 3 is reflected from the traveling wave power P _f by subtracting the power P _r P _L (= P _f -P _r ) is supplied.

Thereafter, when the battery voltage V _j rises to the threshold value V _th in the constant current charging control (step S103; NO), the control unit 24 performs the determination process of step S105. At this time, the charging current I _j is I _jmin <I. _Since it is _j , the control switching unit 24E proceeds to step S111 and switches to the constant voltage charging control to control the output power of the high frequency power source 21.

In the constant voltage charging control, the control unit 24 calculates a difference voltage ΔV _j (= V _cj −V _j ) between the preset constant voltage V _cj and the battery voltage V _j detected by the voltage / current detector 33. (Step S111), a control target value P _CV is generated by multiplying the difference voltage ΔV _j by a predetermined feedback gain (Step S113). Thereafter, the difference power ΔP _f (= P _CV −P _f ) between the control target value P _CV and the traveling wave power P _f detected by the power detector 213 is calculated, and the error amplifying unit 24G The control signal SΔ _P (broken line in FIG. 6A) is generated by multiplying the power ΔP _f by a predetermined feedback gain (step S115). Thereafter, as in the case of constant current charging control is performed the processing of step S117~ step S121, the drive signal S _d to the drive signal generating unit 24M to the drive circuit has generated high-frequency inverter circuit 212 is input, a high frequency inverter circuit The pulsed high-frequency AC power is output from 212, and power is supplied to the power receiving device 3.

By this constant voltage charging control, the battery 34 is charged, and when the charging current I _j decreases to the minimum charging current I _jmin and I _j ≦ I _jmin (step S105; NO), the output stop control unit 24N Assumes that the charging has been completed, the process proceeds to step S123, the output stop control unit 24N performs the output stop process, and ends the power output control.

As described above, the control unit 24 controls the high-frequency inverter circuit 212 of the high-frequency power source 21 so that the high-frequency power source 21 outputs pulsed high-frequency AC power and is adjusted according to the control target values P _CV and P _CI. The output power is supplied to the battery 34.

Next, the waveform of each output signal when the power supplied to the battery 34 (output power from the high frequency power supply 21) is larger or smaller than the control target value P _CV or P _CI is This will be described with reference to FIG.

First, the case where the traveling wave power P _f output from the high frequency power supply 21 is larger than the control target value P _CV or P _CI will be described. In this state, since the traveling wave power P _f exceeds the control target value P _CV or P _CI , the difference power ΔP _f (= P _CV −P _f or P _CI −P _f ) becomes a negative value. In this state, as shown in FIG. 7A, the control signal SΔ _P (indicated by the broken line in the figure) based on the differential power ΔP _f is output at a lower value than in the case of FIG. 6 (indicated by the alternate long and short dash line). Is done. The comparison unit 24J is, by comparing the control signal Esuderuta _P and the carrier signal S _FL, on-off signal S _ON-OFF is generated. The generated off signal S _ON-OFF as compared to the case of FIG. 6, the period of the on-voltage is short, the period of the off-voltage is long off signal S _ON-OFF. Further, since the on-off signal S _ON-OFF based on the pulse-like high-frequency signal S _FH is generated, the high-level period is short, so that the low level period is long pulsed high-frequency signal S _FH is generated. Since the high-frequency inverter circuit 212 is controlled by the drive signal S _d having an output waveform similar to that of the pulse-shaped high-frequency signal S _FH , the high-frequency power P _f output from the high-frequency power source 21 is reduced, and the control target value control is performed so that the difference between the P _CV or P _CI decreases.

Next, the case where the traveling wave power P _f output from the high frequency power source 21 is smaller than the control target value P _CV or P _CI will be described. In this state, since the traveling wave power P _f is lower than the control target value P _CV or P _CI , the difference power ΔP _f (= P _CV −P _f or P _CI −P _f ) becomes a positive value. . In this state, as shown in FIG. 7B, the control signal SΔ _P (indicated by a broken line in the figure) based on the differential power ΔP _f is output higher than in the case of FIG. 6 (indicated by a dashed line). Is done. The comparison unit 24J is, by comparing the control signal Esuderuta _P and the carrier signal S _FL, on-off signal S _ON-OFF is generated. The generated off signal S _ON-OFF as compared to the case of FIG. 6, the period of the on-voltage is increased, a period of off-voltage is short-off signal S _ON-OFF. Further, since the on-off signal S _ON-OFF based on the pulse-like high-frequency signal S _FH is generated, the high-level period is long, so that the high-frequency signal low-level period is short pulsed S _FH is produced. Since the high-frequency inverter circuit 212 is controlled by the drive signal S _d having the same output waveform as the pulse-shaped high-frequency signal S _FH , the high-frequency power P _f output from the high-frequency power source 21 is increased, and the control target value P _{CV Alternatively} , control is performed so that the difference from PCI is small.

As described above, according to the power transmission device 2 according to the present embodiment, the battery voltage V _j and the charging current I _j of the battery 34 are fed back to the control unit 24, and in the constant current charging control period, The output power is controlled to a control target value P _CI which is a compensation value for controlling the charging current Ij to the constant current I _Cj . In the constant voltage charging control period, the output power of the high frequency power source 21 is set to the battery voltage V _j . Control is performed to a control target value P _CV that is a compensation value for controlling to the constant voltage V _Cj . As a result, it is not necessary to provide a charge control device such as a DC / DC converter in the previous stage of the battery 34 as in the prior art, and it is not necessary to perform constant current charge control or constant voltage charge control of the battery 34 with the charge control device. The configuration of the device 3 can be simplified and the cost can be reduced.

  In addition, since the high frequency power supply 21 outputs pulsed high frequency AC power having a high level period and a low level period, the power transmission device 2 is provided with a power control device such as a DC / DC converter, and the high frequency power supply 21 is provided. Therefore, it is not necessary to perform adjustment control of the power output from the power supply, and the configuration of the power transmission device 2 can be simplified and the cost can be reduced.

  Next, output control of the high-frequency AC power output from the high-frequency power source 21 by feedback control of the control unit 24 ′ according to the modification of the present embodiment will be described. In addition, about the same structure as the control part 24 which concerns on this embodiment, the same code number is attached | subjected and the description is abbreviate | omitted.

  The control unit 24 ′ is replaced with the control unit 24, and FIG. 8 is a block diagram showing the configuration of a control system that controls the output power of the high frequency power supply 21 of the control unit 24 ′. As shown in FIG. 8, the control unit 24 ′ includes three adders 24A, 24B, and 24F, three error amplification units 24C, 24D, and 24G, a control switching unit 24E, and a carrier condition setting unit 24H. , A carrier signal generator 24I, a comparator 24J ′, a high frequency condition setting unit 24K, a high frequency signal generator 24L ′, a multiplier 24P, a drive signal generator 24M, and an output stop controller 24N. Consists of.

Comparing portion 24J 'compares the carrier signal S _FL input from the control signal Esuderuta _P and the carrier signal generating unit 24I input from error amplification part 24G, the high-frequency signal generation unit 24L to be described later' high frequency generated by A pulse signal (hereinafter referred to as an on / off signal) S _ON-OFF for controlling on / off of the signal is output to the multiplier 24P. Specifically, the comparing unit 24J 'compares the carrier signal S _FL saw type input from the control signal Esuderuta _P and the carrier signal generating unit 24I input from error amplification part 24G, from the error amplifying section 24G control signal Esuderuta _P are formed so that the oN voltage when a larger carrier signal S _FL from the carrier signal generating unit 24I, whereas, the carrier signal S from the control signal Esuderuta _P carrier signal generator 24I from the error amplifying section 24G _{An ON / OFF} signal S _ON-OFF is generated so that the OFF voltage is obtained when it is equal to or lower than _FL .

The high frequency signal generation unit 24L ′, based on the frequency f and the initial phase φ input from the high frequency condition setting unit 24K, for example, A _n · sin (2πf · t + φ) (A _n : predetermined amplitude) by a direct digital synthesizer. ) Is generated as a sinusoidal high-frequency voltage V _o (high-frequency signal S _F ). Then, the high frequency signal generator 24L 'outputs the generated high frequency signal S _F to the multiplier 24P.

Multiplying unit 24P multiplies the high frequency signal S _F which is input from the comparing section 24J 'OFF signal is input from the S _ON-OFF and the high frequency signal generating unit 24L', the high level period of the high frequency signal is turned on A pulsed high-frequency signal S _FH is generated that alternately repeats a low-level period in which the high-frequency signal is turned _{off at} the frequency of the on / off signal S _ON-OFF . Then, the multiplication unit 24P outputs the generated pulsed high-frequency signal S _FH to the drive signal generation unit 24M. Drive signal generation unit 24M generates a drive signal S _d to drive the drive circuit by a pulse-like high-frequency signal S _FH inputted, and outputs to the drive circuit of the high-frequency inverter circuit 212.

In yet another embodiment, the comparing unit 24J 'compares the carrier signal S _FL saw type input from the control signal Esuderuta _P and the carrier signal generating unit 24I input from error amplification part 24G, the error amplifying section 24G control signal Esuderuta _P are formed so that the carrier signal S _FL high level voltage when larger from the carrier signal generating unit 24I, whereas the control signal Esuderuta _P from the error amplifying section 24G is from the carrier signal generating unit 24I of The on / off signal S _ON-OFF is generated so that the low level voltage is lower than the high level when it is equal to or lower than the carrier signal S _FL . Then, multiplying unit 24P multiplies the high frequency signal S _F which is input from the comparing section 24J 'OFF signal is input from the S _ON-OFF and the high frequency signal generating unit 24L', the amplitude of the high frequency signal to the high level A pulsed high-frequency signal _SFH having a high-level period and a low-level period in which the amplitude of the high-frequency signal is low may be generated.

Next, power output control processing of the high-frequency power source 21 performed by the control unit 24 ′ according to the modification of the present embodiment will be described with reference to FIGS. In the following description, since the remaining capacity of the battery 34 becomes “requires charging”, the electric vehicle is parked at a predetermined charging position and is controlled based on the power supply request output from the power receiving device 3 to the power transmitting device 2. The case where 24 controls the output of the high frequency power supply 21 will be described. As shown in FIG. 9, compared with the flowchart of FIG. 5, the generation processing of the pulsed high-frequency signal S _FH in step S119 is replaced with step S119 ′. In step S119 ′, the multiplication unit 24P performs the on / off signal S _ON-OFF (FIG. 10B) generated by the comparison unit 24J ′ in step S117 and the high-frequency signal S _F generated by the high-frequency signal generation unit 24L ′. (FIG. 10 (c)) is multiplied by a pulsed high-frequency signal S _FH (FIG. 10 (d)) that alternately repeats the high level period and the low level period at the frequency of the on / off signal S _ON-OFF . Generate.

As described above, also in the modification of the present embodiment, the battery voltage V _j and the charging current I _j of the battery 34 are fed back to the control unit 24, and the output power of the high-frequency power source 21 is changed during the constant current charging control period. controls the control target value P _CI is a compensation value for controlling the charging current I _j to a constant current I _Cj, the constant-voltage charging control period, the output power of the high frequency power source 21, a constant voltage battery voltage V _j Control is performed to a control target value P _CV which is a compensation value for controlling to V _Cj . As a result, it is not necessary to provide a charge control device such as a DC / DC converter in the previous stage of the battery 34 as in the prior art, and it is not necessary to perform constant current charge control or constant voltage charge control of the battery 34 with the charge control device. The configuration of the device 3 can be simplified and the cost can be reduced.

  In addition, since the high frequency power supply 21 outputs pulsed high frequency AC power having a high level period and a low level period, the power transmission device 2 is provided with a power control device such as a DC / DC converter, and the high frequency power supply 21 is provided. Therefore, it is not necessary to perform adjustment control of the power output from the power supply, and the configuration of the power transmission device 2 can be simplified and the cost can be reduced.

In the above embodiment, comparison section 24J, an example where 24J 'is compared with the carrier signal S _FL from the control signal Esuderuta _P and a carrier signal generator 24I from the error amplifying section 24G, and generates an off signal S _ON-OFF Although explained, it is not limited to this. For example, comparison unit 24J, includes an on-off signal generator instead of 24J ', the on-off signal generating section includes a period of constant on the voltage that, in accordance with the magnitude of the control signal Esuderuta _P from the error amplifying section 24G An on / off signal S _ON-OFF composed of an off voltage period may be generated. Specifically, off signal generating unit, (in other words, the output power and the control target value from the high-frequency power source 21 is the same) control signal Esuderuta _P is the reference value (zero) from the error amplifying section 24G case, and on-voltage of a certain period of time, to produce the same off-voltage and the period, an on-off signal S _oN-oFF consisting, in accordance with the control signal Esuderuta _P from the error amplifying section 24G is larger than the reference value (high-frequency power source 21 ) in accordance with the output power is smaller than the control target value from, to shorten the duration of the off-voltage, while the control signal Esuderuta _P becomes smaller than the reference value (in accordance with the output power from the high frequency power source 21 is larger than the control target value ) To generate an _{ON / OFF} signal S _{ON-OFF in} which the _OFF voltage period is lengthened. Therefore, by changing the duty ratio of the on-off signal S _ON-OFF in response to a control signal Esuderuta _P output from the error amplifying section 24G, may be adjusted high-frequency AC power output from the high-frequency power supply 21.

  In the above embodiment, since the battery 34 is a secondary battery of constant current and constant voltage charging method, the output control of the high frequency power source 21 is performed by switching between constant current charging control and constant voltage charging control. If 34 can be charged by a constant current charging method or a constant voltage charging method, the configuration may be such that only one of them is performed. In this case, in the constant current charging method, the configurations of the adder 24A, the error amplifying unit 24C, and the control switching unit 24E related to the constant voltage control are deleted in FIG. 4, and the constant voltage charging method is related to the constant current control. The configurations of the adder 24B, the error amplifying unit 24D, and the control switching unit 24E may be deleted.

Furthermore, in the above embodiment, the traveling wave power P _f output from the high frequency power source 21 is controlled. However, instead of the traveling wave power P _f , the power P _L (traveling wave power P _f supplied to the power receiving device 3 is supplied. it may be controlled power) obtained by subtracting the reflected power P _r from. In this case, in FIG. 4, a power calculator that calculates the power P _L by subtracting the reflected wave power P _r from the traveling wave power P _f is provided between the adder 24F and the power detector 213, and the power calculation is performed. The power P _L may be input from the unit to the adder 24F.

Further, the active power P output from the high frequency power source 21 may be controlled instead of the traveling wave power P _f . In this case, an RF detector is provided in place of the power detector 213, and a power calculation unit is provided between the RF detector and the adder 24F, and a high frequency (RF) at the output terminal A of the high frequency power source 21 is provided by the RF detector. The voltage v, the high frequency (RF) current i, and the phase difference θ (the phase difference between the RF voltage v and the RF current i) are detected, and the power calculator calculates the active power P from these detected values and inputs it to the adder 24F. do it. Note that the active power P is calculated by an arithmetic expression of P = V _m · I _m · cos (θ) / 2 where the amplitudes of the RF voltage v and the RF current i are V _m and I _m , respectively.

Alternatively, the reactive power Q may be calculated by the power calculation unit, and the output stop control may be performed using the reactive power Q instead of the reflected wave power _Pr . In this case, sets the threshold Q _th of the reactive power Q to the output stop control unit 24N, enter the reactive power Q calculated by the power calculating portion, the reactive power Q and the threshold Q _th output stop control unit 24N In comparison, when Q _th <Q, the output stop signal S _stop may be output to the error amplifying units 24C and 24D.

  In addition, although the electric vehicle charging system using the non-contact power transmission system 1 has been described in the above embodiment, the present invention is not limited to the electric vehicle charging system, and may be a mobile phone, a portable terminal, or the like. The present invention can also be applied to a non-contact charging device that charges a secondary battery.

Also, as shown in FIG. 11, in FIG. 1, the configuration (power transmission unit 23 and power reception unit 31) that wirelessly transmits high-frequency AC power to the battery 34 side, and the detected values of the battery voltage V _j and charging current I _j wirelessly. Is connected to the control unit 24 (communication units 25 and 35), the impedance matching device 22 and the rectifying / smoothing circuit 32 are directly connected, and the voltage / current detector 33 and the control unit 24 are connected to each other to connect the charging device 4 May be configured to transmit the high-frequency AC power, the battery voltage V _j, and the detected value of the charging current I _j by wire.

In the above embodiment, switching between the first level and the second level of the pulsed high-frequency AC power is performed by providing the high-frequency signal S _FH generated in the control unit 24 with a high level and a low level. However, the present invention is not limited to this. Instead of providing a high level and a low level for the high-frequency signal S _FH , it may be performed by switching the voltage input to the switching circuit of the high-frequency inverter circuit 212. For example, as shown in FIGS. 12 and 13, a commercial frequency voltage is input from a commercial power source, and after full-wave rectification, capacitors (C ₁₁ and C ₁₂ in FIG. 12, C ₂₁ and C _{22 in} FIG. 13) are set to 2 Input to the series circuit. Then, a total of three terminals, that is, a positive output terminal, a negative output terminal of the two series capacitors, and a terminal of the two series connection portions are connected to the high frequency inverter circuit 212 ′ to output pulsed high frequency power. You may make it make it. Note that the configuration shown in FIG. 12 is a circuit configuration obtained by modifying the half-bridge circuit, and the configuration shown in FIG. 13 is a circuit configuration obtained by modifying the full-bridge circuit. In FIG. 12 and FIG. 13, Q _{11 to} Q ₁₄ and Q _{21 to} Q ₂₆ are MOSFETs similarly to Q _{B of the} above embodiment.

12, the control unit 24 receives the off signal S _ON-OFF to the gate of Q ₁₁ and Q _12, a high frequency power supply so as to enter the drive signal based on the high frequency signal S _F to the gate of Q ₁₃ and Q ₁₄ 21 is controlled. For example, in FIG. 12A, when Q ₁₁ is on and Q ₁₂ is off, the voltage output from the rectifier circuit is applied to the switching circuit composed of Q ₁₃ and Q ₁₄ and the high-frequency AC power P _out (High-frequency AC voltage V _out ) is at the first level. When Q ₁₁ is off and Q ₁₂ is on, a voltage obtained by dividing the voltage output from the rectifier circuit with capacitors C ₁₁ and C ₁₂ is applied to the switching circuit composed of Q ₁₃ and Q ₁₄ . The high-frequency AC power P _out (high-frequency AC voltage V _out ) is at the second level. As a result, pulsed high-frequency AC power is output from the high-frequency power source 21. FIG. 12 (b), the Q ₁₁ and Q _12, but on the negative electrode side of the switching circuit consisting of Q ₁₃ and Q _14. Further, in FIG. 13, the control unit 24 receives the off signal S _ON-OFF to the gate of Q ₂₁ and Q _22, to enter the drive signal based on the high frequency signal S _F to the gate of from Q ₂₃ Q ₂₆ By controlling the high-frequency power source 21, pulsed high-frequency AC power is output from the high-frequency power source 21. As a result, similarly to the above-described embodiment, pulsed high-frequency AC power can be output from the high-frequency power source 21, and further, power loss due to switching of the high-frequency power source 21 can be further reduced.

  Moreover, in the said embodiment, although the secondary battery was demonstrated to the example as a to-be-charged body, as long as a to-be-charged object is charged by direct current, it will not be limited to a secondary battery, For example, an electric double layer capacitor or a lithium ion capacitor may be used. In the above-described embodiment, the charging device that charges the object to be charged has been described. However, the present invention converts alternating current power to direct current power and determines the direct current power for a load that is supplied with direct current power. The present invention can be widely applied to a DC power supply device that supplies a load with current control or constant voltage control.

DESCRIPTION OF SYMBOLS 1 Non-contact electric power transmission system 2 Power transmission apparatus 21 High frequency power supply (electric power generation means)
211 Rectifier circuit 212 High-frequency inverter circuit 213 Power detector 22 Impedance matching device (impedance adjusting means)
23 Power Transmission Unit 231 Inductor 232 Capacitor 24, 24 ′ Control Unit (Control Unit)
24A, 24B, 24F Adder 24C, 24D, 24G Error amplification unit 24E Control switching unit 24H Carrier condition setting unit 24I Carrier signal generation unit (carrier signal generation means)
24J, 24J 'comparison part (comparison means)
24K high frequency condition setting unit 24L, 24L 'high frequency signal generating unit (high frequency signal generating means)
24M Drive signal generator (drive signal generator)
24N output stop control unit 24P multiplication unit (high-frequency signal generating means)
25, 35 Communication unit 3 Power receiving device 31 Power receiving unit 311 Inductor 312 Capacitor 32 Rectification smoothing circuit (power conversion means)
33 Voltage / current detector (detection means)
34 Battery (load)
4 Charger

Claims (12)

A power generating means having a high frequency inverter and outputting high frequency AC power;
Power conversion means for converting the high-frequency AC power to DC power and supplying the load to the load;
Detecting means for detecting an electrical physical quantity related to DC power supplied to the load;
A pulse signal having a frequency lower than the frequency of the high-frequency AC power is generated, and based on the generated pulse signal, the high-frequency AC power output from the power generation means is changed to the on state or the first level. The pulsed high-frequency AC power that alternately repeats the first period and the second period in which the high-frequency AC power is in the off state or the second level lower than the first level at the frequency of the pulse signal, Control means for controlling the power generation means by adjusting the waveform of the pulse signal so that the detected physical quantity becomes a predetermined target value;
A direct-current power supply device comprising: The control means adjusts a pulse width of the pulse signal based on a difference between the physical quantity detected by the detection means and the target value;
The direct-current power supply apparatus according to claim 1. The control means includes
A difference signal generating means for calculating a difference between the physical quantity detected by the detecting means and the target value, and generating a difference signal indicating the difference information;
Carrier signal generating means for generating a carrier signal;
Comparison means for comparing the difference signal and the carrier signal, and generating the pulse signal based on the comparison result;
Based on the pulse signal, a pulsed high-frequency signal that alternately repeats a first period in which the high-frequency signal is turned on or at a high level and a second period in which the high-frequency signal is turned off or at a low level at the frequency of the pulse signal High-frequency signal generating means for generating
Comprising
The power generation means controls the high frequency inverter according to the pulsed high frequency signal, and outputs the pulsed high frequency AC power.
The direct-current power supply device according to claim 1 or 2, wherein The control means includes
A difference signal generating means for calculating a difference between the physical quantity detected by the detecting means and the target value, and generating a difference signal indicating the difference information;
Carrier signal generating means for generating a carrier signal;
Comparison means for comparing the difference signal and the carrier signal, and generating the pulse signal based on the comparison result;
High-frequency signal generating means for generating a high-frequency signal;
The first period in which the high-frequency signal is turned on or at a high level and the second period in which the high-frequency signal is turned off or at a low level by multiplying the high-frequency signal by the high-frequency signal generator and the pulse signal from the comparator. Multiplication means for generating a pulsed high-frequency signal that alternately repeats the period at the frequency of the pulse signal;
Comprising
The power generation means controls the high frequency inverter according to the pulsed high frequency signal, and outputs the pulsed high frequency AC power.
The direct-current power supply device according to claim 1 or 2, wherein The comparison means is an on voltage or the high level voltage when the difference signal is larger than the carrier signal, and is an off voltage or the low level voltage when the difference signal is equal to or less than the carrier signal. Generate a pulse signal,
The direct-current power supply device according to claim 3 or 4, wherein The control means makes the on-voltage period of the pulse signal constant, and adjusts the off-voltage period of the pulse signal based on the difference between the physical quantity detected by the detection means and the target value;
The direct-current power supply apparatus according to claim 1. The physical quantity detected by the detection means is an average value for each predetermined period of the pulse signal.
The DC power supply device according to any one of claims 1 to 6, wherein The physical quantity detected by the detection means is at least one of direct current, direct current voltage, or direct current power.
The DC power supply apparatus according to any one of claims 1 to 7, wherein Impedance adjustment that is provided between the power generation means and the power conversion means, and adjusts the impedance viewed from the output end to the load side so that the reflected wave power at the output end of the power generation means is a predetermined value or less. Means further comprising:
The DC power supply device according to any one of claims 1 to 8, wherein A pair of coils magnetically coupled to each other is provided between the impedance adjusting means and the power converting means, and the AC power output from the power generating means is contactlessly communicated through the pair of coils. Transmitted to the
The DC power supply apparatus according to claim 9. The load is a secondary battery or a livestock appliance.
The DC power supply apparatus according to any one of claims 1 to 10, wherein A first step of operating a high-frequency inverter and outputting high-frequency AC power;
A second step of converting the high-frequency AC power into DC power and supplying it to a load;
A third step of detecting an electrical physical quantity relating to DC power supplied to the load;
A pulse signal having a frequency lower than the frequency of the high-frequency AC power is generated. Based on the generated pulse signal, the high-frequency AC power output by the first step is turned on or at a first level. A first period and a second period in which the high-frequency AC power is in an off state or a second level lower than the first level are changed to pulsed high-frequency AC power that alternately repeats at the frequency of the pulse signal, and the third step A fourth step of controlling the high-frequency AC power output by the first step by adjusting the waveform of the pulse signal so that the detected physical quantity becomes a predetermined target value;
A DC power supply method comprising:

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