Power output circuit and non-contact power supply system

Abstract

A power output circuit (OC1) includes a plurality of circuit blocks (30) provided in power wirings (WP1, WP2) to which power is input and connected in parallel with each other, each of the plurality of circuit blocks having at least a filter (16) in the last stage, each of the plurality of filters has a reactor (L1) and a capacitor (C1) connected to the reactor at a node different from the output node (Nout), and either the reactor or the capacitor of each of the plurality of filters is connected in series to the power wiring so as to be connected to the output node. And the connecting line of the reactor and the capacitor in one filter is connected with the connecting lines of the reactors and the capacitors in the rest filters.

Description

Citation of related applications

[0001] This application is based on Japanese Patent Application No. 2022-92228 filed on June 7, 2022, and the contents thereof are incorporated herein by reference. Technical Field

[0002] The present disclosure relates to a power output circuit and a contactless power supply system. Background Art

[0003] Conventionally, in a power transmission path, a filter circuit is used to obtain a target frequency component, etc. For example, in Patent Document 1, a filter circuit for suppressing high-frequency harmonic noise is used in a power transmission device for contactless power supply. Prior art literature Patent Literature

[0004] Patent Document 1: Japanese Patent Application Publication No. 2016-25771 Summary of the invention

[0005] In order to increase the power supply of the already set power transmission path to the load in the future, it is considered to add a new power transmission path including a filter circuit in parallel to the already set power transmission path including the filter circuit. In this case, for electronic components such as reactors or capacitors used in the filter circuit, if the component characteristics of the inductor or capacitor are biased, the output current of each filter circuit is unbalanced between multiple filter circuits, which may increase power loss. Such technical problems occur not only when the power transmission path including the power source is connected in parallel, but also when only the filter circuit is connected in parallel.

[0006] The present disclosure can be implemented in the following forms.

[0007] In one embodiment of the present disclosure, a power output circuit is provided. The power output circuit includes a plurality of circuit blocks, the plurality of circuit blocks are arranged in a power distribution line for power input and are connected in parallel to each other, each of the plurality of circuit blocks has at least a filter at the last stage, the plurality of filters respectively have a reactor and a capacitor connected to the reactor at a node different from an output node, any one of the reactors and capacitors possessed by each of the plurality of filters is connected in series with the power distribution line in a manner connected to the output node, and a connection line between the reactor and the capacitor in one of the filters is connected to a connection line between the reactor and the capacitor in the remaining other filters.

[0008] According to the power output circuit of this mode, since the connection lines of a plurality of filters are connected, the deviation of the current value and transient characteristics of the output current of each filter can be suppressed. Therefore, the increase of power loss of the reactor or capacitor caused by the current imbalance caused by the element characteristics of the reactor or capacitor can be suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The above objects, other objects, features and advantages of the present disclosure will become more apparent with reference to the accompanying drawings and the following detailed description. Figure 1 1 is a circuit diagram of a power output circuit according to the first embodiment. Figure 2 2 is a circuit diagram of a power output circuit according to a second embodiment. Figure 3 : is a circuit diagram of the power output circuit of the third embodiment. Figure 4 4 is a circuit diagram of a contactless power supply system according to a fourth embodiment. Figure 5 1 is a circuit diagram of a contactless power supply system according to a fifth embodiment. Figure 6 1 is a circuit diagram of a contactless power supply system according to a sixth embodiment. Figure 7 1 is a circuit diagram of a contactless power supply system according to a seventh embodiment. Figure 8 1 is a circuit diagram of a contactless power supply system according to an eighth embodiment. Fig. 9 1 is a circuit diagram of a contactless power supply system according to a ninth embodiment. DETAILED DESCRIPTION

[0010] A. First Implementation Method: like Figure 1 As shown, the power output circuit OC1 is sandwiched between the AC power source 22 and the load 70 supplied with power from the AC power source 22. Specifically, the power output circuit OC1 is provided in the first power wiring WP1 and the second power wiring WP2 as power wirings for inputting the AC power output from the AC power source 22, and has two circuit blocks 30 connected in parallel to each other. Specifically, the two circuit blocks 30 are connected in parallel to each other. In the present embodiment, each circuit block 30 has a filter 16. In the present embodiment, the filter 16 is a bandpass filter formed by connecting a first reactor L1 and a first capacitor C1 in series. The filter 16 suppresses passage of noise components and passes signals of a target frequency band.

[0012] The first reactor L1 and the first capacitor C1 are connected in series on the first power wiring WP1. Specifically, one terminal of the first capacitor C1 is connected to the output node Nout of the power output circuit OC1, and the other terminal is connected to one terminal of the first reactor L1 at a node different from the output node Nout. The other terminal of the first reactor L1 is connected to one terminal of the AC power supply 22. The connection line between the first reactor L1 and the first capacitor C1 in one filter 16 is connected to the connection line between the first reactor L1 and the first capacitor C1 in the remaining other filters 16. That is, the connection lines between the first reactor L1 and the second capacitor C2 of each of the two filters 16 are connected by the wiring W1. As a result, since the potential difference between the connection lines can be eliminated, even if there is a deviation in the inductance of the first reactor L1 or the capacitance of the first capacitor C1, it is possible to suppress the deviation in the current value or transient characteristics of the output current of the output node Nf of each filter 16, that is, the output current. Therefore, it is possible to suppress an increase in loss in the first reactor L1 and the first capacitor C1 due to current imbalance caused by variations in element characteristics of the first reactor L1 and the first capacitor C1 , specifically, inductance and capacitance.

[0013] In addition, the inventors confirmed through simulation that by connecting the first reactor L1 and the connection line of the second capacitor C2, the imbalance of the output current of each filter 16 between the two filters 16 can be suppressed. In addition, when the first reactor L1 and the connection line of the second capacitor C2 are connected, the inventors also confirmed the characteristics representing the relationship between the frequency and the attenuation through simulation, and confirmed that the filter performance is not reduced. Therefore, by connecting the first reactor L1 and the connection line of the second capacitor C2, the current imbalance of the output current between the filters can be suppressed without reducing the filter performance.

[0014] According to the first embodiment described above, the power output circuit OC1 includes two filters 16, and the connection lines between the first reactor L1 and the second capacitor C2 of each filter 16 are connected by the wiring W1. Thus, even if there is a deviation in the element characteristics of the first reactor L1 or the first capacitor C1, it is possible to suppress the deviation in the current value or transient characteristics of the output current of each filter 16. Therefore, it is possible to suppress the increase in the loss of the first reactor L1 or the first capacitor C1 caused by the current imbalance caused by the deviation in the element characteristics of the first reactor L1 or the first capacitor C1.

[0015] B. Second Implementation Method: like Figure 2As shown, the circuit block 230 of the power output circuit OC2 of the present embodiment is different from that of the first embodiment in that it includes an inverter 14 in addition to the filter 216. In addition, the filter 16 of the first embodiment is a bandpass filter, whereas the filter 216 of the present embodiment is a combination of a bandpass filter and a bandstop filter. The same symbols are given to the same structures as those of the first embodiment, and detailed descriptions are appropriately omitted.

[0016] The power output circuit OC2 of this embodiment has two circuit blocks 230, which are provided in the first power wiring WP1 and the second power wiring WP2 for inputting the AC power output from the DC power supply 24, and are connected in parallel with each other. In this embodiment, the circuit block 230 has an inverter 14 and a filter 216. The filter 216 is arranged at the last stage of the circuit block 230. Here, the latter stage refers to the downstream side in the power flow direction with the power source such as the AC power supply 22 as the upstream and the load such as the load 70 to which the power is supplied as the downstream. The same is true for the former stage described later. That is, the former stage refers to the upstream side in the power flow direction.

[0017] The inverter 14 converts the DC power output from the DC power supply 24 into AC power. The filter 216 suppresses the passage of the noise component of the input AC power and allows the signal of the target frequency band to pass. The filter 216 is composed of a first filter unit F1 as a bandpass filter, a second filter unit F2 as a bandstop filter, and a third filter unit F3 as a bandpass filter connected in sequence. The first filter unit F1 is composed of a connection body formed by connecting the first inductor L1 and the first capacitor C1 in series and inserting it in series into the first power wiring WP1. The second filter unit F2 is composed of a connection body formed by connecting the second inductor L2 and the second capacitor C2 in parallel to the DC power supply 24 in parallel. The third filter unit F3 is composed of a connection body formed by connecting the third inductor L3 and the third capacitor C3 in series and inserting it in series into the first power wiring WP1.

[0018] In the present embodiment, the connection lines inside each of the two filters 216 are also connected by the wiring W1. Specifically, the connection line between the third reactor L3 and the third capacitor C3 connected to the output node Nout is connected by the wiring W1. Thus, the same effect as the first embodiment can be achieved, and even if the current value or transient characteristics of the output current of the two inverters 14 of the power output circuit OC2 differ, the deviation of the current value or transient characteristics of the output current of each filter 216 can be suppressed.

[0019] The second embodiment described above can achieve the same effects as the above embodiment, and even when the output currents of the two inverters 14 of the power output circuit OC2 differ, the deviations in the output current values ​​and transient characteristics of the filters 216 can be suppressed.

[0020] C. Third Implementation Method: like Figure 3 As shown, the circuit block 330 of the power output circuit OC3 of this embodiment is different from the second embodiment in that it includes the AC / DC converter 12 in addition to the filter 316 and the inverter 14. In addition, the filter 316 of this embodiment is different from the above-mentioned embodiments in that it is configured as a fourth-order filter. The same symbols are attached to the same structures as those in the above-mentioned embodiments, and detailed descriptions are appropriately omitted.

[0021] The power output circuit OC3 of this embodiment has two circuit blocks 330, which are provided in the first power wiring WP1 and the second power wiring WP2 for inputting the AC power output from the AC power source 22, and are connected in parallel with each other. In this embodiment, the circuit block 330 has the AC / DC converter 12, the inverter 14, and the filter 316. The filter 316 is arranged at the last stage of the circuit block 330.

[0022] The AC / DC converter 12 converts the AC power output from the AC power source 22 into a DC voltage of a target voltage value and supplies it to the inverter 14. The filter 316 is configured as a fourth-order filter. Specifically, a connection body formed by connecting the first inductor L1 and the second inductor L2 in series is inserted in series into the first power wiring WP1. Between the first inductor L1 and the second inductor L2, the first capacitor C1 is inserted in parallel with the AC power source 22. Behind the second inductor L2, the second capacitor C2 is inserted in parallel with the AC power source 22.

[0023] In this embodiment, the connection lines inside each of the two filters 316 are also connected by the wiring W1. Specifically, the connection line between the first capacitor C1 and the second reactor L2 connected to the output node Nout is connected by the wiring W1. As a result, the same effect as the above-mentioned embodiments can be achieved, and even if the current values ​​of the output currents of the two AC / DC converters 12 of the power output circuit OC2 differ, the deviation of the current value and transient characteristics of the output current of each filter 316 can be suppressed.

[0024] According to the third embodiment described above, the same effect as the above embodiment can be achieved, and even when there is a difference in the output current of the two AC / DC converters 12 of the power output circuit OC2, the deviation of the current value or transient characteristics of the output current of each filter 316 can be suppressed.

[0025] D. Fourth Implementation Method: like Figure 4 As shown, in this embodiment, the power output circuit OC4 and the power receiving side power output circuit OCR4 as the power output circuit are incorporated into the contactless power supply system 1. Figure 4 As shown, the contactless power supply system 1 includes a power transmission device 10 and a power reception device 80. The power transmission device 10 supplies power to the power reception device 80 in a contactless manner.

[0026] The power output circuit OC4 has two circuit blocks 430 connected in parallel. Each circuit block 430 has a filter 416. The filter 416 of this embodiment is different from the above embodiments and is configured as a fifth-order filter. The same symbols are attached to the same structures as the above embodiments, and detailed descriptions are appropriately omitted.

[0027] The filter 416 attenuates the noise component, i.e., the harmonic component, of the high-frequency power of the high-frequency AC power input from the AC power supply 22, passes the power of the target frequency band, and supplies it to the power transmission coil Ls. In addition, in the present embodiment, high frequency refers to power of a frequency above 1 kHz. The filter 416 inserts a connection body formed by connecting the first inductor L1, the second inductor L2, and the third inductor L3 in series into the first power wiring WP1. Moreover, between the first inductor L1 and the second inductor L2, the first capacitor C1 is connected in parallel with the AC power supply 22, and between the second inductor L2 and the third inductor L3, the second capacitor C2 is connected in parallel with the AC power supply 22. The power transmission coil Ls is connected to the subsequent stage of the circuit block 430.

[0028] The power receiving device 80 includes a power receiving coil Lr, a power receiving side power output circuit OCR4, a rectifier circuit 86, and a battery 88. When the power receiving coil Lr is arranged at a position where it can be magnetically coupled with the power transmitting coil Ls, an electromotive force is generated in the power receiving coil Lr by electromagnetic induction caused by the magnetic flux generated by the power transmitting coil Ls. The electromotive force generated in the power receiving coil Lr is input to the first power wiring WPr1 and the second power wiring WPr2 as power wiring.

[0029] The power receiving side power output circuit OCR4 is arranged on the first power wiring WPr1 and the second power wiring WPr2. The power receiving side power output circuit OCR4 has two circuit blocks 84 connected in parallel to each other. Each circuit block 84 has a filter 90. In the present embodiment, the filter 90 is configured as a fifth-order filter having a fourth inductor L4, a fifth inductor L5, a sixth inductor L6, a third capacitor C3, and a fourth capacitor C4. The filter 90 attenuates the harmonic components of the AC power input from the power receiving coil Lr.

[0030] The rectifier circuit 86 converts the input AC power into DC power and supplies the DC power to the battery 88. When power is supplied to the power receiving device 80, the power transmission coil Ls and the power receiving device 80 can be regarded as a load.

[0031] In the present embodiment, the internal connection lines of the two filters 416 are also connected by the wiring W1 and the wiring W2. Specifically, the connection line between the second capacitor C2 and the third reactor L3 connected to the output node Nout is connected by the wiring W2. The connection line between the second reactor L2 and the first capacitor C1 is connected by the wiring W1. Thus, even if there is a deviation in the inductance of each reactor or the capacitance of each capacitor, the deviation of the current value or transient characteristics of the output current of each filter 416 can be suppressed.

[0032] Similarly, the connection lines inside each of the two filters 90 included in the power receiving device 80 are connected by wiring W3 and wiring W4. Specifically, the connection line between the fourth capacitor C4 and the sixth reactor L6 connected to the output node Nrout of the power output circuit OCR4 on the power receiving side is connected by wiring W4. In addition, the connection line between the third capacitor C3 and the fifth reactor L5 is connected by wiring W3. Thus, as with the power output circuit OC4, even if there is a deviation in the inductance of each reactor or the capacitance of each capacitor, it is possible to suppress the deviation in the current value or transient characteristics of the output current of each filter 90.

[0033] According to the fourth embodiment described above, the same effects as those of the above-described embodiments are achieved. In addition, by including the power output circuit OC4 in the power transmission device 10, the harmonic noise of the power transmitted by the first power wiring WP1 and the second power wiring WP2 can be attenuated. In addition, by including the power receiving side power output circuit OCR4 in the power receiving device 80, the harmonic noise of the power transmitted by the first power wiring WPr1 and the second power wiring WPr2 can be attenuated. Therefore, it is possible to provide a non-contact power supply system 1 in which the radiation of harmonic noise is appropriately attenuated.

[0034] E. Fifth Implementation Method: like Figure 5As shown, this embodiment is the same as the fourth embodiment in that the power output circuit OC5 and the power receiving side power output circuit OCR4 are assembled in the contactless power supply system 501. In addition, the circuit block 530 of this embodiment is different from the fourth embodiment in that it has an inverter 14, a power transmission resonance circuit 18, and a circuit structure of the filter 516. In addition, the power receiving device 580 of this embodiment is different from the fourth embodiment in that it has a power receiving resonance circuit 82. The same symbols are attached to the same structures as those in the above-mentioned embodiments, and detailed descriptions are appropriately omitted.

[0035] The circuit block 530 of this embodiment includes the inverter 14 as in the second embodiment. The filter 516 is a combination of a bandpass filter and a bandstop filter. Specifically, a first filter unit F1 as a bandpass filter and a second filter unit F2 as a bandstop filter are sequentially connected.

[0036] The power transmission resonance circuit 18 is a resonance circuit in which a power transmission resonance capacitor Cs and a power transmission coil Ls are connected in series. The power transmission resonance circuit 18 is in a resonance state at the fundamental frequency of the AC power output from the inverter 14. In the present embodiment, the fundamental frequency is 85 kHz.

[0037] The power receiving resonance circuit 82 is a resonance circuit in which the power receiving coil Lr and the power receiving resonance capacitor Cr are connected in series. When the power transmitting coil Ls and the power receiving coil Lr are magnetically coupled, the resonance frequency of the power transmitting resonance circuit 18 and the resonance frequency of the power receiving resonance circuit 82 are set to be substantially the same. Thus, contactless power supply from the power transmitting device 510 to the power receiving device 580 can be performed by resonance of the magnetic field between the power transmitting coil Ls and the power receiving coil Lr.

[0038] In this embodiment, the power receiving device 580 is mounted on a vehicle (not shown). The battery 88 is a secondary battery that outputs DC power for driving a drive motor as a drive source of the vehicle. The power transmission resonance circuit 18 included in the power transmission device 10 is installed on a road on which the vehicle travels.

[0039] In this embodiment, the connection lines inside the two filters 516 are also connected by the wiring W1. Specifically, the connection line between the first reactor L1 and the first capacitor C1 connected to the output node Nout is connected by the wiring W1. This achieves the same effects as the above embodiments.

[0040] In this embodiment, each circuit block 530 is unitized. Specifically, in the circuit block 530, the electronic components constituting the inverter 14 and the filter 516 are fixed to a substrate, and external connection terminals T1 to T5 are provided on the substrate. The external connection terminal T1 and the external connection terminal T3 are provided in the first power wiring WP1. The external connection terminal T2 and the external connection terminal T4 are provided in the second power wiring WP2. The external connection terminal T1 and the external connection terminal T2 are terminals on the input side of the circuit block 530, and the external connection terminal T3 and the external connection terminal T4 are terminals on the output side of the circuit block 530. The external connection terminal T5 is provided in the wiring W1.

[0041] When the power transmission device 510 is installed on a road, the DC power supply 24, the unitized circuit block 530, and the power transmission resonance circuit 18 are separately arranged. The DC power supply 24 and the circuit block 530, and the circuit block 530 and the power transmission resonance circuit 18 are connected by power wiring. In addition, the circuit block 530 may be arranged in a housing (not shown) and the external connection terminals T1 to T5 may be exposed from the housing.

[0042] In the present embodiment, the circuit block 530 includes the inverter 14 on the premise that the DC power supply 24 has sufficient power supply capacity, thereby making it possible to flexibly change the power supply capacity of the power transmission device 510. Specifically, when the power transmission device 510 wants to increase the power supplied to the power transmission resonance circuit 18, the supply capacity can be increased by adding a new circuit block 530 in parallel to the already provided circuit block 530. On the contrary, when the power supplied by the power transmission device 510 is reduced, the supply capacity can be reduced by removing a part of the already provided circuit blocks 530. In the present embodiment, since the circuit block 530 is unitized, the input power wiring and the output power wiring of the circuit block 530 can be easily connected or disconnected using the pre-provided external connection terminals T1 to T5. In addition, since the circuit block 530 is unitized, the circuit constants of the inverter 14 and the filter 516 provided in the circuit block 530 can be optimized.

[0043] In addition, the advantage of the circuit block 530 being unitized is not limited to the case where the power transmission device 510 is provided. In the present embodiment, the case where the power receiving device 580 is installed in a vehicle is illustrated, but the object on which the power receiving device 580 is installed is not limited to the vehicle, and it may be other mobile bodies such as AGV (automatic guided vehicle). Moreover, in the contactless power supply system 501, the size of the power of the contactless power supply varies depending on the object on which the power receiving device 580 is installed. In the case of manufacturing the circuit blocks 530 to be respectively suitable for each of the various power sizes of the contactless power supply, it is necessary to classify the various circuit blocks 530. In view of this point, according to the present embodiment, by increasing or decreasing the number of circuit blocks 530, it is possible to correspond to the various power sizes of the contactless power supply without classifying the various circuit blocks 530.

[0044] According to the fifth embodiment described above, the same effects as those of the above-mentioned embodiments are achieved. In addition, the power transmission device 510 includes the power transmission resonance capacitor Cs, and the power receiving device 580 includes the power reception resonance capacitor Cr, thereby enabling contactless power supply through magnetic resonance (Japanese: magnetic resonance). In addition, since the circuit block 530 includes the inverter 14 and the circuit block 530 is unitized, the power supply capacity of the power transmission device 510 can be flexibly changed on the premise that the DC power supply 24 has sufficient power supply capacity.

[0045] F. Sixth embodiment: like Figure 6 As shown, the power transmission device 610 of the contactless power supply system 601 of this embodiment is different from the fifth embodiment in that it has an AC / DC converter 12, a circuit structure of a filter 616, and a circuit structure of a power transmission resonance circuit 618. In addition, the circuit structure of a power receiving resonance circuit 682 of this embodiment is different from that of the fifth embodiment. The same reference numerals are given to the same structures as those in the above-mentioned embodiments, and detailed descriptions are appropriately omitted.

[0046] As in the third embodiment, the circuit block 630 of this embodiment includes the AC / DC converter 12. The filter 616 is a balanced bandpass filter. Specifically, a first connection body formed by connecting the first inductor L1 and the first capacitor C1 in series is provided in the first power wiring WP1, and a second connection body formed by connecting the second inductor L2 and the second capacitor C2 in series, which is the same connection body as the first connection body, is provided in the second power wiring WP2. By adopting a balanced type, common mode noise can be reduced.

[0047] In the present embodiment, the internal connection lines of the two filters 616 are also connected by the wiring W1 and the wiring W2. Specifically, the connection line between the first reactor L1 and the first capacitor C1 connected to the output node Nout is connected by the wiring W1. In addition, in the present embodiment, the connection line between the second reactor L2 of the second connection body set in the second power wiring WP2 and the first capacitor C1 in one filter 616 is connected to the connection line between the second reactor L2 and the second capacitor C2 of the second connection body set in the second power wiring WP2 in the remaining other filters 616. Specifically, the connection line between the second reactor L2 and the second capacitor C2 is connected by the wiring W2. The wiring W1 and the wiring W2 are arranged closely, and in the present embodiment, the wiring W1 and the wiring W2 are twisted together. Therefore, since the wiring W1 and the wiring W2 are paired, the wiring inductance can be reduced, and the potential difference between the connection lines can be further eliminated. Therefore, the deviation of the current value and transient characteristics of the output current of each filter 616 can be suppressed. In addition, since each line has a balanced structure, common mode noise can be further reduced.

[0048] The power transmission resonance circuit 618 of this embodiment is different from the fifth embodiment in that it is a resonance circuit in which the power transmission resonance capacitor Cs and the power transmission coil Ls are connected in parallel. In addition, the power receiving resonance circuit 682 of this embodiment is different from the fifth embodiment in that it is a resonance circuit in which the power receiving resonance capacitor Cr and the power receiving coil Lr are connected in parallel. Although the structure is different, the contactless power supply system 1 includes the power transmission resonance circuit 618 and the power receiving resonance circuit 682, and can perform contactless power supply through the magnetic field resonance of the power transmission coil Ls and the power receiving coil Lr as in the fifth embodiment.

[0049] In this embodiment, the circuit block 630 is also unitized. In addition, in this embodiment, unlike the fifth embodiment, since the power output circuit OC6 has the wiring W2 in addition to the wiring W1, it has an external connection terminal T6 provided in the wiring W2 in addition to the external connection terminals T1 to T5. By unitizing the circuit block 630, the power supply capacity of the power transmission device 610 can be flexibly changed. In addition, since the circuit block 630 is unitized, the circuit constants of the AC / DC converter 12, the inverter 14, and the filter 516 included in the circuit block 630 can be optimized.

[0050] In this embodiment, the circuit block 630 includes the AC / DC converter 12 and the inverter 14, on the premise that the AC power source 22 has sufficient supply capacity, and thus, as in the fifth embodiment, it is possible to flexibly change the power supply capacity of the power transmission device 610. That is, when it is desired to increase the power supplied by the power transmission device 610, a new circuit block 630 is added, and when it is desired to reduce the power supplied by the power transmission device 610, the supply capacity can be increased or decreased by removing the circuit block 630.

[0051] According to the sixth embodiment described above, the same effects as those of the above embodiments are achieved. In addition, since the circuit block 630 has the AC / DC converter 12, the circuit block 630 is unitized, thereby enabling the power supply capacity of the power transmission device 610 to be flexibly changed provided that the AC power source 22 has sufficient supply capacity.

[0052] G. Seventh Implementation Method: like Figure 7 As shown, the number of circuit blocks 730, the number of power transmission resonance circuits 18, and the configuration of the filter 716 of the contactless power supply system 701 of this embodiment are different from those of the sixth embodiment. The same reference numerals are used for the same configurations as those of the above embodiments, and detailed descriptions thereof are omitted as appropriate.

[0053] In the present embodiment, the power transmission device 710 includes three circuit blocks 730. The filter 716 is a balanced filter. Specifically, a first connector is provided in the first power wiring WP1, and the first connector includes a first inductor L1 and a second inductor L2 connected in series with each other, and a first capacitor C1 connected in parallel with the AC power supply 22 between the first inductor L1 and the second inductor L2. A second connector is provided in the second power wiring WP2, and the second connector is a connector equivalent to the first connector, and includes a third inductor L3 and a fourth inductor L4 connected in series with each other, and a first capacitor C1 connected in parallel between the third inductor L3 and the fourth inductor L4. Behind the fourth inductor L4, the second capacitor C2 is connected in parallel with the AC power supply 22. By adopting a balanced type, common mode noise can be reduced.

[0054] As in the sixth embodiment, the internal connection lines of the three filters 616 are connected by wiring W1 and wiring W2. Specifically, the connection lines of the first inductor L1 of each of the three filters 616 and the second inductor L2 connected to the output node Nout are connected by wiring W1. The connection lines of the third inductor L3 and the fourth inductor L4 of each of the three filters 616 are connected by wiring W2. The wiring W1 and the wiring W2 are arranged close to each other. Thus, the deviation of the current value and transient characteristics of the output current of each filter 716 can be suppressed, and since the wiring W1 and the wiring W2 are paired, the common mode noise can be further reduced.

[0055] In the present embodiment, the power transmission device 710 has four power transmission resonance circuits 18. The four power transmission resonance circuits 18 are connected in parallel with each other. In the present embodiment, a case where contactless power is supplied to a plurality of power receiving devices 580 using a plurality of power transmission resonance circuits 18 supplied with power from the same AC power supply 22 is exemplified. In the case where contactless power is supplied to a plurality of power receiving devices 580, the magnitude of the output power of the power output circuit OC7 is larger than that in the case where contactless power is supplied to a single power receiving device 580. In this case, as described above, by adding the circuit block 730, the magnitude of the output power of the power transmission device 710 can be adjusted. According to the seventh embodiment described above, the same effects as those of the above-described embodiments are achieved.

[0056] H. Eighth Implementation Method: like Figure 8 As shown, the contactless power supply system 801 of this embodiment is different from the fifth embodiment in that the power transmission device 810 includes a three-phase inverter 814. The same reference numerals are used for the same configurations as those in the above-mentioned embodiments, and detailed descriptions thereof are omitted as appropriate.

[0057] The circuit block 830 of the power output circuit OC8 of this embodiment includes a three-phase inverter 814. The three-phase inverter 814 converts DC power input from the DC power supply 24 into three-phase AC power and outputs it to the third power wiring WP3, the fourth power wiring WP4, and the fifth power wiring WP5 as power wiring.

[0058] The two circuit blocks 830 are connected in parallel with each other. Here, the parallel connection means that in addition to the case of connecting in parallel as in the above-mentioned embodiments, a plurality of circuit blocks 830 are connected as in the present embodiment, and the output nodes Nf of the same phase of the AC power output from each circuit block 830 are connected to each other so that the AC power output from each circuit block 830 merges.

[0059] The filter 816 is arranged in the third power wiring WP3, the fourth power wiring WP4 and the fifth power wiring WP5. Specifically, a connection body in which the first inductor L1 and the first capacitor C1 are connected in series is inserted in each of the third power wiring WP3, the fourth power wiring WP4 and the fifth power wiring WP5. Power is supplied to the power transmission resonance circuit 18 through any two power wirings among the third power wiring WP3, the fourth power wiring WP4 and the fifth power wiring WP5.

[0060] In this embodiment, the internal connection lines of the two filters 816 are also connected by wiring W1, wiring W2 and wiring W3. Specifically, the first inductor L1 provided in the third power wiring WP3 and the connection line of the first capacitor C1 connected to the output node Nout are connected by wiring W1. The first inductor L1 provided in the fourth power wiring WP4 and the connection line of the first capacitor C1 are connected by wiring W2. The first inductor L1 provided in the fifth power wiring WP5 and the connection line of the first capacitor C1 are connected by wiring W3. Thus, the deviation of the current value and transient characteristics of the output current of each filter 816 can be suppressed. According to the eighth embodiment described above, the same effect as the above-mentioned embodiments is achieved.

[0061] I. Ninth embodiment: like Fig. 9 As shown, the power transmission device 910 of the contactless power supply system 901 of this embodiment is different from the sixth embodiment in that it also has a control circuit 42, a current detection circuit 44, and a current sensor 46 as a control unit and a circuit structure of a filter 916. The control circuit 42 and the current detection circuit 44 are implemented by electronic circuits. The same symbols are marked for the same structures as those in the above-mentioned embodiments, and detailed descriptions are appropriately omitted.

[0062] The filter 916 included in the circuit block 930 included in the power output circuit OC9 of the present embodiment is a balanced filter. Specifically, a first connection body is provided in the first power wiring WP1, and the first connection body includes a first reactor L1, a second reactor L2, and a third reactor L3 connected in series with each other, a first capacitor C1 connected in parallel with the AC power supply 22 between the first reactor L1 and the second reactor L2, and a second capacitor C2 connected in parallel with the AC power supply 22 between the second reactor L2 and the third reactor L3. In addition, a second connection body is provided in the second power wiring WP2, and the second connection body is provided as a connection body similar to the first connection body, and includes a fourth reactor L4, a fifth reactor L5, and a sixth reactor L6 connected in series with each other, a first capacitor C1 connected in parallel with the AC power supply 22 between the fourth reactor L4 and the fifth reactor L5, and a second capacitor C2 connected in parallel with the AC power supply 22 between the fifth reactor L5 and the sixth reactor L6. By adopting a balanced type, common mode noise can be reduced.

[0063] As in the sixth embodiment, the internal connection lines of the two filters 916 are connected by wiring W1, wiring W2, wiring W3 and wiring W4. Specifically, the connection line between the second capacitor C2 and the third inductor L3 connected to the output node Nout is connected by wiring W1. The connection line between the sixth inductor L6 and the second capacitor C2 is connected by wiring W2. The connection line between the first capacitor C1 and the second inductor L2 is connected by wiring W3. The connection line between the fifth inductor L5 and the first capacitor C1 is connected by wiring W4. Wiring W1 is arranged close to wiring W2. Wiring W3 is arranged close to wiring W4. As a result, the deviation of the current value and transient characteristics of the output current of each filter 916 can be suppressed, and the common mode noise can be further reduced.

[0064] The current sensor 46 is arranged at the output node Nf of each of the two filters 916. The current sensor 46 detects the output current of each of the two filters 916, and inputs a signal indicating the magnitude of the current value to each of the two current detection circuits 44. The control circuit 42 controls the duty ratio of the PWM signal used to control the inverter 14 so that the difference between the output current of one filter 916 and the output current of the remaining other filters 916 becomes smaller. Specifically, the current detection circuit 44 compares the signals indicating the magnitude of the current values ​​input from the two current sensors 46, and inputs a signal indicating the difference in the current values ​​of the output currents of each of the two filters 916, i.e., the current difference, to the control circuit 42. The control circuit 42 uses the signal input from the current detection circuit 44 to adjust the input signal to the inverter 14 to reduce the current difference. Specifically, the duty ratio of the input signal, i.e., the PWM signal, input to the transistor constituting the inverter 14 is changed. For example, when the output current of one filter 916 is large, the duty ratio of the PWM signal for the inverter 14 that inputs power to one filter 916 is reduced. This makes it possible to further suppress variations in the current values ​​of the output currents of the filters 916 .

[0065] According to the ninth embodiment described above, the same effects as those of the above-described embodiments are achieved, and since the current sensor 46 , the current detection circuit 44 , and the control circuit 42 are provided, variations in the current values ​​of the output currents of the filters 916 can be further suppressed.

[0066] J. Other implementations: (J1) In the fourth embodiment described above, the filter 90 included in the power receiving device 80 is a fifth-order filter similar to the filter 416 included in the power transmitting device 10. However, the filter structures may be different between the power receiving device 80 and the power transmitting device 10. Regardless of the filter structure, by including the filter in the power transmitting device 10 and the power receiving device 80, noise components can be appropriately attenuated.

[0067] (J2) In the first embodiment, the first reactor L1 and the first capacitor C1 are connected in series in sequence between the AC power supply 22 and the load 70. The connection order of the first reactor L1 and the first capacitor C1 may be reversed. Regardless of whether it is a reactor or a capacitor, an electronic element having one terminal connected to the output node Nout and connected in series with the first power wiring WP1 through the connection between the connecting line of the reactor and the capacitor can suppress the imbalance of the output current of the filter.

[0068] (J3) In the fourth embodiment, the filter 416 is provided in the stage before the power transmission coil Ls of the power transmission device 10, and the filter 90 is provided in the stage after the power receiving coil Lr of the power receiving device 80. Different from this embodiment, a filter may be provided in only one of the stage before the power transmission coil Ls and the stage after the power receiving coil Lr.

[0069] The present disclosure is not limited to the above-mentioned embodiments and variations, and can be implemented by various structures within the scope of the above-mentioned purpose. For example, the technical features in each embodiment and variation corresponding to the technical features in each method described in the invention content section can be appropriately replaced or combined to solve part or all of the above-mentioned technical problems, or to achieve part or all of the above-mentioned effects. In addition, the above-mentioned technical features can be appropriately deleted as long as they are not described as necessary structures in this specification.

[0070] Although the present disclosure is described based on the embodiments, it should be understood that the present disclosure is not limited to the above-mentioned embodiments and structures. The present disclosure also includes various modifications and modifications within the equivalent range. In addition, various combinations and methods, and other combinations and methods containing only one element, above or below them, also belong to the scope and thought range of the present disclosure.

[0071] The features of the present disclosure are as follows. (Method 1) A power output circuit, The power output circuit (OC1-OC9, OCR4) includes a plurality of circuit blocks (30, 230-930), which are arranged in power wiring (WP1-WP5, WPr1, WPr2) for power input and are connected in parallel with each other. Each of the plurality of circuit blocks has at least a filter (16, 90, 216 to 916) at the last stage, The plurality of filters each include a reactor (L1) and a capacitor (C1) connected to the reactor at a node different from the output node (Nout). Any one of the reactor and the capacitor included in each of the plurality of filters is connected in series with the power wiring so as to be connected to the output node. The connection line between the reactor and the capacitor in one of the filters is connected to the connection line between the reactor and the capacitor in the remaining other filters. (Method 2) A contactless power supply system, the contactless power supply system (1, 501-901) comprising the power output circuit described in method 1, The power output circuit is a circuit that outputs high-frequency power. The filter is a filter for attenuating high-frequency harmonic components of the electric power. The above-mentioned contactless power supply system comprises: A power transmission device (10, 510-910), the power transmission device having a power transmission coil; and a power receiving device (80, 580), the power receiving device having a power receiving coil for receiving power from the power transmitting coil using electromagnetic induction, The power output circuit is provided in at least one of a stage before the power transmission coil and a stage after the power reception coil. (Method 3) In the contactless power supply system described in embodiment 2, The power transmission device further includes a power transmission resonance capacitor (Cs) which forms a power transmission resonance circuit together with the power transmission coil. The power receiving device further includes a power receiving resonance capacitor (Cr) forming a power receiving resonance circuit together with the power receiving coil. (Method 4) In the power output circuit described in embodiment 1, The above-mentioned filters are band-pass filters. (Method 5) In the power output circuit described in embodiment 1, The above filter is a combination of a bandpass filter and a bandstop filter. (Method 6) In the power output circuit described in embodiment 1, The above filter is a fourth-order filter. (Method 7) In the power output circuit described in embodiment 1, The above filter is a fifth-order filter. (Method 8) In the power output circuit described in embodiment 1, The power wiring includes a first power wiring (WP1) and a second power wiring (WP2). A first connection body including the reactor and the capacitor is provided in the first power wiring. The filter is a balanced filter having a second connection body equivalent to the first connection body in the second power wiring. The connection line between the reactor and the capacitor of the second connection body provided in the second power distribution line in one of the filters is connected to the connection line between the reactor and the capacitor of the second connection body provided in the second power distribution line in the remaining other filters. (Method 9) In the contactless power supply system described in embodiment 2 or 3, The power transmission device further comprises an AC / DC converter (12) for converting AC power into DC power and outputting the DC power. The power output circuit is arranged at the rear stage of the AC / DC converter and the front stage of the power transmission coil. Each of the plurality of circuit blocks has an inverter (14). The inverter converts the DC power into the high-frequency power and outputs the high-frequency power to the filter. Each of the plurality of circuit blocks described above is unitized. (Method 10) In the contactless power supply system described in embodiment 2 or 3, The power output circuit is arranged at the previous stage of the power transmission coil. Each of the above-mentioned multiple circuit blocks has: an AC / DC converter (12) that converts AC power into DC power and outputs the DC power; and an inverter (14), the inverter converting the DC power into the high-frequency power and outputting the high-frequency power to the filter, Each of the plurality of circuit blocks described above is unitized. (Method 11) In the contactless power supply system described in aspect 9 or 10, The power transmission device further comprises: a plurality of current sensors (46), the plurality of current sensors detecting output currents of the plurality of filters respectively; and A control unit (42) controls a duty cycle of a PWM signal for controlling the inverter using the plurality of output currents detected by the plurality of current sensors so as to reduce a difference between the output current of one of the filters and the output currents of the remaining other filters.

Claims

1. A power output circuit, The power output circuit (OC1-OC9, OCR4) includes a plurality of circuit blocks (30, 230-930), the plurality of circuit blocks are arranged in a power wiring (WP1-WP5, WPr1, WPr2) for power input, and are connected in parallel with each other, Each of the plurality of circuit blocks has at least a filter (16, 90, 216-916) at the last stage, The plurality of filters each include a reactor (L1) and a capacitor (C1) connected to the reactor at a node different from the output node (Nout). One of the reactor and the capacitor included in each of the plurality of filters is connected in series with the power wiring so as to be connected to the output node. The connection lines between the reactor and the capacitor in one of the filters are connected to the connection lines between the reactor and the capacitor in the remaining other filters.

2. A contactless power supply system, The contactless power supply system (1, 501-901) comprises the power output circuit according to claim 1, The power output circuit is a circuit that outputs high-frequency power. The filter is a filter for attenuating high-frequency harmonic components of the electric power, The contactless power supply system comprises: A power transmission device (10, 510-910), the power transmission device having a power transmission coil; as well as a power receiving device (80, 580) having a power receiving coil for receiving power from the power transmitting coil using electromagnetic induction, The power output circuit is provided in at least one of a stage before the power transmission coil and a stage after the power reception coil.

3. The contactless power supply system according to claim 2, characterized in that: The power transmission device further includes a power transmission resonance capacitor (Cs) which forms a power transmission resonance circuit together with the power transmission coil. The power receiving device further includes a power receiving resonance capacitor (Cr) which forms a power receiving resonance circuit together with the power receiving coil.

4. The power output circuit according to claim 1, characterized in that: The filter is a bandpass filter.

5. The power output circuit according to claim 1, characterized in that: The filter is a combination of a bandpass filter and a bandstop filter.

6. The power output circuit according to claim 1, characterized in that: The filter is a fourth order filter.

7. The power output circuit according to claim 1, characterized in that: The filter is a fifth order filter.

8. The power output circuit according to claim 1, characterized in that: The power wiring has a first power wiring (WP1) and a second power wiring (WP2), A first connection body including the reactor and the capacitor is provided in the first power wiring. The filter is a balanced filter having a second connection body equivalent to the first connection body in the second power wiring. The connection line between the reactor and the capacitor of the second connection body provided in the second power wiring in one of the filters is connected to the connection line between the reactor and the capacitor of the second connection body provided in the second power wiring in the remaining other filters.

9. The contactless power supply system according to claim 3, characterized in that: The power transmission device further includes an AC / DC converter (12) for converting AC power into DC power and outputting the DC power. The power output circuit is provided at a stage after the AC / DC converter and before the power transmission coil. Each of the plurality of circuit blocks has an inverter (14) that converts the DC power into the high-frequency power and outputs the high-frequency power to the filter. Each of the plurality of circuit blocks is unitized.

10. The contactless power supply system according to claim 3, characterized in that: The power output circuit is arranged at the previous stage of the power transmission coil. Each of the plurality of circuit blocks has: an AC / DC converter (12) for converting AC power into DC power and outputting the DC power; as well as an inverter (14) that converts the DC power into the high-frequency power and outputs the high-frequency power to the filter, Each of the plurality of circuit blocks is unitized.

11. The contactless power supply system according to claim 9 or 10, characterized in that: The power transmission device further comprises: a plurality of current sensors (46), the plurality of current sensors detecting the output current of each of the plurality of filters; and A control unit (42) controls a duty ratio of a PWM signal for controlling the inverter using the plurality of output currents detected by the plurality of current sensors so as to reduce a difference between the output current of one filter and the output currents of the remaining other filters.

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