Power supply device

Abstract

To provide a power supply device that is compact and can be configured at low cost. [Solution] The inverter 10 is provided with a first leg 11 in which switching elements 11H and 11L are connected in series, and a second leg 12 in which switching elements 12H and 12L are connected in series, and converts AC power to DC power; a converter 20 converts DC power from the inverter 10 to DC power; and a first reactor coil 30 with one terminal 30B connected to the first node 11N of the first leg 11, wherein AC power is supplied across the other terminal 30A of the first reactor coil 30 and the second node 12N of the second leg 12, and the inverter 10 has a third leg 13 in which switching elements 13H and 13L are connected in series, and a second reactor coil 40 is provided across the second node 12N of the second leg 12 and the third node 13N of the third leg 13.

Description

Technical Field

[0004] , , , , , , , ,

[0006] , , , ,

[0005] , , , , , ,

[0001] The present invention relates to a power supply device for charging and discharging a battery mounted on a vehicle.

Background Art

[0002] Conventionally, vehicles that run on electric energy (e.g., hybrid vehicles and electric vehicles) have been used. Such vehicles are equipped with a battery, and the battery is configured to be charged from an external power source. When charging such a battery, there may be a desire to use an AC voltage having a voltage value different from the voltage value of the AC voltage used for charging the battery. As a technology that can be used in such a case, for example, there is one described in Patent Document 1 whose citation is shown below.

[0003] Patent Document 1 describes a charger for charging a battery. This charger includes a power factor correction circuit connected to AC power, a DC conversion circuit having one end connected to the power factor correction circuit and the other end connected to the battery, and an AC conversion circuit into which power is input and that outputs AC power. The power factor correction circuit, the DC conversion circuit, and the AC conversion circuit are each configured separately.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] As described above, since the charger described in Patent Document 1 has the power factor correction circuit, the DC conversion circuit, and the AC conversion circuit each configured separately, it causes an increase in size and an increase in cost.

[0006] Therefore, there is a need for a power supply device that can be configured to be small and low-cost. [Means for solving the problem]

[0007] The characteristic configuration of the power supply device according to the present invention is that it comprises an inverter that converts AC power to DC power, an inverter that converts the DC power from the inverter to DC power that can charge a battery, and a first reactor coil with one terminal connected to a first node between the two switching elements in the first leg, wherein the AC power is supplied across the other terminal of the first reactor coil and the second node between the two switching elements in the second leg, and the inverter has a third leg provided in parallel with the first and second legs, with a high-side switching element and a low-side switching element connected in series, and a second reactor coil provided across the second node of the second leg and the third node between the two switching elements in the third leg.

[0008] With this configuration, the high-side and low-side switching elements of the second leg can be shared for both the conversion of AC power to DC power by the inverter and the energization of the second reactor coil. As a result, the AC power input to the inverter is converted to DC power based on the high-side and low-side switching elements of the first leg and the high-side and low-side switching elements of the second leg, and the second reactor coil is energized based on the high-side and low-side switching elements of the third leg and the high-side and low-side switching elements of the second leg. Therefore, when performing the conversion of AC power to DC power by the inverter and the energization of the second reactor coil, the size of the power supply unit can be reduced and the cost can be lowered compared to when the second leg is not shared (when they are provided separately).

[0009] Furthermore, it is preferable that the inverter converts the AC power into DC power based on the driving of the switching elements in the first and second legs, and converts the AC power into AC power different from the said AC power based on the driving of the switching elements in the second and third legs.

[0010] With this configuration, the battery mounted on the vehicle can be charged based on the AC power input to the inverter, and AC power can be generated based on the energy stored in the second reactor coil. Furthermore, by setting the voltage value of the AC voltage that constitutes the AC power generated from the energy stored in the second reactor coil to a voltage value suitable for use with electrical appliances, for example, it becomes possible to charge the battery and supply power to electrical appliances simultaneously, thereby improving convenience.

[0011] Furthermore, it is preferable that the phase of the signal that drives the switching element in the third leg is the same as the phase of the AC power input to and output to the first leg and the second leg.

[0012] With this configuration, the inverter can simultaneously output DC power capable of charging the vehicle's battery and AC power capable of powering other electrical appliances, based on the AC power input. Therefore, it is possible to use electrical appliances while charging the battery, further improving convenience. [Brief explanation of the drawing]

[0013] [Figure 1] This is a circuit diagram showing the configuration of the power supply unit. [Figure 2] This diagram illustrates the driving mechanism of a switching element. [Modes for carrying out the invention]

[0014] The power supply device according to the present invention is configured to output DC power for charging a battery mounted on a vehicle, and also to output AC power different from the AC power supplied to the power supply device. The power supply device 1 of this embodiment will be described below.

[0015] Figure 1 is a circuit diagram of power supply unit 1. As shown in Figure 1, power supply unit 1 comprises an inverter 10, a converter 20, a first reactor coil 30, a second reactor coil 40, and a control unit 50. Each functional unit is built with a CPU as its core component, and is constructed using hardware, software, or both, to perform the processing related to the output of DC power and AC power as described above.

[0016] The inverter 10 converts AC power to DC power. In this embodiment, AC power refers to power composed of AC voltages whose voltage value oscillates with a predetermined period. Specifically, the AC voltage corresponds to a 200V (RMS) AC voltage taken from a commercial power supply that oscillates at a commercial frequency (e.g., 50Hz or 60Hz) and is supplied in a single-phase three-wire system. DC power refers to power composed of DC voltages that have a constant voltage value (excluding ripple voltage) relative to a reference voltage. The inverter 10 converts such AC power composed of AC voltages into DC power composed of DC voltages. The inverter 10 is provided with a pair of output units 10A and 10B, and outputs the converted DC power to the converter 20, which will be described later, via this pair of output units 10A and 10B.

[0017] The inverter 10 has a first leg 11, a second leg 12, and a third leg 13. The first leg 11, the second leg 12, and the third leg 13 are arranged in parallel with respect to the output sections 10A and 10B. As a result, one end 11A of the first leg 11, one end 12A of the second leg 12, and one end 13A of the third leg 13 are connected to the output section 10A, and the other end 11B of the first leg 11, the other end 12B of the second leg 12, and the other end 13B of the third leg 13 are connected to the output section 10B.

[0018] The first leg 11 has a high-side switching element 11H and a low-side switching element 11L connected in series. In this embodiment, n-type MOS-FETs (metal-oxide-semiconductor field-effect transistors) are used for the switching elements 11H and 11L. The drain terminal of the switching element 11H is connected to end 11A, and the source terminal is connected to the drain terminal of the switching element 11L. The source terminal of the switching element 11L is connected to end 11B. The gate terminals of the switching elements 11H and 11L are connected to the control unit 50. Diodes 11HD and 11LD are provided between the source terminals and drain terminals of the switching elements 11H and 11L, respectively, with the anode terminal connected to the source terminal and the cathode terminal connected to the drain terminal.

[0019] Furthermore, the second leg 12 has a high-side switching element 12H and a low-side switching element 12L connected in series. In this embodiment, n-type MOS-FETs are also used for the switching elements 12H and 12L. The drain terminal of the switching element 12H is connected to end 12A, and the source terminal is connected to the drain terminal of the switching element 12L. The source terminal of the switching element 12L is connected to end 12B. The gate terminals of the switching elements 12H and 12L are connected to the control unit 50. Diodes 12HD and 12LD are also provided between the source terminals and drain terminals of the switching elements 12H and 12L, respectively, with the anode terminal connected to the source terminal and the cathode terminal connected to the drain terminal.

[0020] Furthermore, the third leg 13 has a high-side switching element 13H and a low-side switching element 13L connected in series. In this embodiment, n-type MOS-FETs are also used for the switching element 13H and the switching element 13L. The drain terminal of the switching element 13H is connected to the end 13A, and the source terminal is connected to the drain terminal of the switching element 13L. The source terminal of the switching element 13L is connected to the end 13B. The gate terminals of the switching element 13H and the switching element 13L are each connected to the control unit 50. Also, between the source terminal and the drain terminal of each of the switching element 13H and the switching element 13L, diodes 13HD and 13LD are provided, with the anode terminal connected to the source terminal and the cathode terminal connected to the drain terminal.

[0021] A capacitor 15 is provided across the output part 10A and the output part 10B of the inverter 10. The capacitor 15 smoothes the DC voltage converted by the inverter 10.

[0022] One terminal 30B of the first reactor coil 30 is connected to the first node 11N between the two switching elements (the switching element 11H and the switching element 11L) in the first leg 11. The first node 11N between the two switching elements in the first leg 11 is a line (e.g., a wiring pattern on a substrate or a cable such as a harness) connecting the source terminal of the switching element 11H and the drain terminal of the switching element 11L. Of course, it may be the source terminal of the switching element 11H or the drain terminal of the switching element 11L. The first reactor coil 30 has two terminals 30A and 30B, and the terminal 30B is connected to the first node 11N.

[0023] AC power is supplied across the other terminal 30A of the first reactor coil 30 and the second node 12N between the two switching elements (switching element 12H and switching element 12L) in the second leg 12. The second node 12N between the two switching elements in the second leg 12 is a line (e.g., a wiring pattern on a substrate or a cable such as a harness) connecting the source terminal of the switching element 12H and the drain terminal of the switching element 12L. Of course, it may be the source terminal of the switching element 12H or the drain terminal of the switching element 12L. The terminal 30A of the first reactor coil 30 is connected to one terminal of the supply unit 2 to which AC power is supplied, and the other terminal of the supply unit 2 is connected to the second node​​​​​​​​​​​The first conversion unit 21 inputs the DC power from the inverter 10 to the primary winding 24A, with the amplitude adjusted to a predetermined period. The first conversion unit 21 has a fourth leg 211 and a fifth leg 212, and the fourth leg 211 and the fifth leg 212 are arranged in parallel with respect to the output units 10A and 10B. Therefore, one end 211A of the fourth leg 211 and one end 212A of the fifth leg 212 are connected to the output unit 10A, and the other end 211B of the fourth leg 211 and the other end 212B of the fifth leg 212 are connected to the output unit 10B.

[0027] The fourth leg 211 has a high-side switching element 211H and a low-side switching element 211L connected in series. n-type MOS-FETs are used for both switching elements 211H and 211L. The drain terminal of switching element 211H is connected to end 211A, and the source terminal is connected to the drain terminal of switching element 211L. The source terminal of switching element 211L is connected to end 211B. The gate terminals of switching elements 211H and 211L are connected to the control unit 50. Diodes 211HD and 211LD are provided between the source terminals and drain terminals of switching elements 211H and 211L, respectively, with their anode terminals connected to the source terminals and their cathode terminals connected to the drain terminals.

[0028] The fifth leg 212 has a high-side switching element 212H and a low-side switching element 212L connected in series. n-type MOS-FETs are used for both switching elements 212H and 212L. The drain terminal of switching element 212H is connected to end 212A, and the source terminal is connected to the drain terminal of switching element 212L. The source terminal of switching element 212L is connected to end 212B. The gate terminals of switching elements 212H and 212L are connected to the control unit 50. Diodes 212HD and 212LD are provided between the source terminals and drain terminals of switching elements 212H and 212L, respectively, with their anode terminals connected to the source terminals and their cathode terminals connected to the drain terminals.

[0029] The primary winding 24A is provided across the fourth node 211N between two switching elements (switching element 211H and switching element 211L) in the fourth leg 211 and the fifth node 212N between two switching elements (switching element 212H and switching element 212L) in the fifth leg 212. In this embodiment, the starting end of the primary winding 24A is connected to the fourth node 211N, and the ending end of the primary winding 24A is connected to the fifth node 212N.

[0030] A current (alternating current) flows through the secondary winding 24B in proportion to the turns ratio between the primary winding 24A and the secondary winding 24B, and a voltage (alternating voltage) is generated in proportion to the turns ratio between the primary winding 24A and the secondary winding 24B. The second conversion unit 22 rectifies the voltage (alternating voltage) generated in the secondary winding 24B. The second conversion unit 22 has a sixth leg 221 and a seventh leg 222, and the sixth leg 221 and the seventh leg 222 are provided in parallel with each other to the output units 20A and 20B of the converter 20. Therefore, one end 221A of the sixth leg 221 and one end 222A of the seventh leg 222 are connected to the output unit 20A, and the other end 221B of the sixth leg 221 and the other end 222B of the seventh leg 222 are connected to the output unit 20B.

[0031] The sixth leg 221 has a high-side switching element 221H and a low-side switching element 221L connected in series. n-type MOS-FETs are used for both switching elements 221H and 221L. The drain terminal of switching element 221H is connected to end 221A, and the source terminal is connected to the drain terminal of switching element 221L. The source terminal of switching element 221L is connected to end 221B. The gate terminals of switching elements 221H and 221L are connected to the control unit 50. Diodes 221HD and 221LD are provided between the source terminals and drain terminals of switching elements 221H and 221L, respectively, with their anode terminals connected to the source terminals and their cathode terminals connected to the drain terminals.

[0032] The seventh leg 222 has a high-side switching element 222H and a low-side switching element 222L connected in series. n-type MOS-FETs are used for both switching elements 222H and 222L. The drain terminal of switching element 222H is connected to end 222A, and the source terminal is connected to the drain terminal of switching element 222L. The source terminal of switching element 222L is connected to end 222B. The gate terminals of switching elements 222H and 222L are connected to the control unit 50. Diodes 222HD and 222LD are provided between the source terminals and drain terminals of switching elements 222H and 222L, respectively, with their anode terminals connected to the source terminals and their cathode terminals connected to the drain terminals.

[0033] The secondary winding 24B described above is provided across the sixth node 221N between two switching elements (switching element 221H and switching element 221L) in the sixth leg 221 and the seventh node 222N between two switching elements (switching element 222H and switching element 222L) in the seventh leg 222. In this embodiment, the starting end of the secondary winding 24B is connected to the sixth node 221N, and the ending end of the secondary winding 24B is connected to the seventh node 222N.

[0034] A capacitor 25 is provided across the output sections 20A and 20B of the converter 20. The capacitor 25 smooths the DC voltage converted by the converter 20.

[0035] A current (alternating current) flows through the tertiary winding 24C in proportion to the turns ratio between the primary winding 24A and the tertiary winding 24C, and a voltage (alternating voltage) is generated in proportion to the turns ratio between the primary winding 24A and the tertiary winding 24C. The third conversion unit 23 rectifies the voltage (alternating voltage) generated in the tertiary winding 24C.

[0036] In this embodiment, the tertiary winding 24C has a first tertiary winding 24CA and a second tertiary winding 24CB. The first tertiary winding 24CA and the second tertiary winding 24CB are provided by connecting the end of the winding of the first tertiary winding 24CA to the beginning of the winding of the second tertiary winding 24CB. The anode terminal of diode 23D1 is connected to the beginning of the winding of the first tertiary winding 24CA. The cathode terminal of diode 23D1 is connected to one terminal of the third reactor coil 23L. The other terminal of the third reactor coil 23L is connected to the output section 23A of the third conversion unit 23. The anode terminal of diode 23D2 is connected to the end of the winding of the second tertiary winding 24CB. The cathode terminal of diode 23D2 is connected to one terminal of the third reactor coil 23L. The end of the first tertiary winding 24CA and the beginning of the second tertiary winding 24CB are connected to the output section 23B of the third conversion section 23. A capacitor 23C is provided across the output sections 23A and 23B.

[0037] The second reactor coil 40 is provided extending from the second node 12N of the second leg 12 to the third node 13N between the two switching elements (switching element 13H and switching element 13L) in the third leg 13. The third node 13N between the two switching elements in the third leg 13 is a wire (for example, a wiring pattern on a circuit board or a cable such as a harness) connecting the source terminal of switching element 13H and the drain terminal of switching element 13L. Of course, it may also be the source terminal of switching element 13H or the drain terminal of switching element 13L. In this embodiment, terminal 40A of the second reactor coil 40 is connected to one terminal of an outlet 4 capable of outputting AC power, and the other terminal of the outlet 4 is connected to the second node 12N. Terminal 40B of the second reactor coil 40 is connected to the third node 13N. Therefore, it is possible to extract AC power consisting of an AC voltage of a predetermined voltage value (for example, 100V (RMS)) from the outlet 4.

[0038] The control unit 50 alternately drives the switching elements 11H and 11L of the first leg 11, and the second leg 12 alternately drives the switching elements 12H and 12L at the grid frequency (see Figure 2). This enables the inverter 10 to convert AC power to DC power based on the driving of the switching elements of the first leg 11 and the second leg 12.

[0039] Furthermore, the control unit 50 alternately drives the switching element 211H of the fourth leg 211 and the switching element 212L of the fifth leg 212, and the switching element 211L of the fourth leg 211 and the switching element 212H of the fifth leg 212. As a result, the DC power from the inverter 10 is amplified and input to the primary winding 24A, and AC power is generated in the secondary winding 24B according to the turns ratio between the primary winding 24A and the secondary winding 24B.

[0040] Furthermore, the control unit 50 alternately drives the switching element 221H of the sixth leg 221 and the switching element 222L of the seventh leg 222, and the switching element 221L of the sixth leg 221 and the switching element 222H of the seventh leg 222. This makes it possible to convert the AC power generated in the secondary winding 24B into DC power.

[0041] By setting the turns ratio of the primary winding 24A and the secondary winding 24B to correspond to the ratio of the AC voltage applied to the primary winding 24A to the DC voltage used to charge the battery 3, it becomes possible to generate DC power suitable for charging the battery 3 in the output units 20A and 20B, thereby enabling the battery 3 to be charged.

[0042] An AC voltage corresponding to the turns ratio between the primary winding 24A and the tertiary winding 24C is generated in the tertiary winding 24C. This voltage is rectified by diodes 23D1 and 23D2, the third reactor coil 23L, and capacitor 23C, and DC power consisting of a predetermined DC voltage is output from output units 23A and 23B. For example, by setting this voltage to 12V, it becomes possible not only to charge battery 3 with the power supply unit 1, but also to charge a 12V battery installed in a different vehicle.

[0043] Furthermore, the power supply unit 1 is configured to output the AC power supplied to the supply unit 2 as other AC power from the outlet 4. Specifically, it is configured to convert the 200V AC voltage supplied from the supply unit 2 so that it can output a 100V AC voltage from the outlet 4. In this case, the control unit 50 alternately drives the switching elements 13H and 13L of the third leg 13, and the second leg 12 alternately drives the switching elements 12H and 12L at the grid frequency (see Figure 2). This makes it possible for the inverter 10 to convert the AC power input to the inverter 10 into AC power different from the AC power based on the driving of the switching elements of the second leg 12 and the third leg 13. In other words, when charging the battery 3, a 200V AC voltage is applied to the inverter 10, but it is possible to output a 100V AC voltage from the outlet 4.

[0044] When the control unit 50 drives each switching element as described above, it controls the phase of the signal that drives the switching element in the third leg 13 to be the same phase as the AC power input to and output to the first leg 11 and the second leg 12.

[0045] Figure 2(A) shows the voltage waveform of the AC voltage (200V) that constitutes the AC power supplied to the power supply unit 2. Figure 2(B) shows the signal input to the gate terminal of the switching element 11H of the first leg 11, and Figure 2(C) shows the signal input to the gate terminal of the switching element 11L of the first leg 11. Figure 2(D) shows the signal input to the gate terminal of the switching element 12H of the second leg 12, and Figure 2(E) shows the signal input to the gate terminal of the switching element 12L of the second leg 12. Figure 2(F) shows the signal input to the gate terminal of the switching element 13H of the third leg 13, and Figure 2(G) shows the signal input to the gate terminal of the switching element 13L of the third leg 13. Figure 2(H) shows the voltage waveform of the AC voltage (100V) that constitutes the AC power output from the outlet 4.

[0046] As shown in Figures 2(D) and (E), the control unit 50 drives the switching elements of the second leg 12 at the same frequency (e.g., 50Hz or 60Hz) as the AC power supplied to the supply unit 2 and the AC power output from the outlet 4. As shown in Figures 2(B), (C), (F), and (G), the control unit 50 drives the switching elements 11H and 11L of the first leg 11 and the switching elements 13H and 13L of the third leg 13 by PWM control at a control frequency (e.g., several hundred kHz) that enables the power supply unit 1 to convert DC power to charge the battery 3 and output AC power that can be used to power electrical appliances via the outlet 4. This allows the power supply unit 1 to charge the battery 3, and at the same time, it enables the outlet 4 to output an AC voltage with a voltage value different from the AC voltage input to the supply unit 2 as shown in Figure 2(A) (a voltage as shown in Figure 2(H)).

[0047] Furthermore, the on-duty cycles of the signal input to the gate terminal of the switching element 13H of the third leg 13 shown in Figure 2(F), and the signal input to the gate terminal of the switching element 13L of the third leg 13 shown in Figure 2(G), should be changed according to the AC power output from outlet 4.

[0048] [Other Embodiments] In the above embodiment, the switching elements of the inverter 10 and converter 20 were described as n-type MOS-FETs, but the switching elements may also be p-type MOS-FETs, or other switching elements (for example, IGBTs or bipolar transistors).

[0049] In the above embodiment, an example was given in which the third conversion unit 23 is equipped with diodes 23D1 and 23D2, but instead of diodes 23D1 and 23D2, for example, MOS-FETs may be used.

[0050] In the above embodiment, the inverter 10 was described as converting AC power to DC power based on the driving of the switching elements of the first leg 11 and the second leg 12, and converting the AC power input to the inverter 10 to other AC power based on the driving of the switching elements of the second leg 12 and the third leg 13. However, the inverter 10 may also be configured to output the same AC power from the outlet 4 as the AC power input to the inverter 10 when the switching elements of the second leg 12 and the third leg 13 are driven.

[0051] In the above embodiment, it was explained that the phase of the signal driving the switching element of the third leg 13 is the same as the phase of the AC power input and output to the first leg 11 and the second leg 12. However, the phase of the signal driving the switching element of the third leg 13 may differ from the phase of the AC power input and output to the first leg 11 and the second leg 12 within a predetermined range. Also, although the rising and falling edges of each signal were shown to coincide, they do not have to coincide.

[0052] This invention can be used in power supply devices mounted on vehicles. [Explanation of Symbols]

[0053] 1: Power supply 3: Battery 10: Inverter 11: First Leg 11H: Switching element 11L: Switching element 12: Leg 2 12H: Switching element 12L: Switching element 12N: Second node 13: Third Leg 13H: Switching element 13L: Switching element 13N: Third node 20: Converter 30: First Reactor Coil 30A: Terminal 30B:Terminal 40: Second Reactor Coil

Claims

1. An inverter that converts AC power to DC power, comprising a first leg in which a high-side switching element and a low-side switching element are connected in series, and a second leg in which a high-side switching element and a low-side switching element are connected in series, arranged in parallel with each other. A converter that converts the DC power from the inverter into DC power that can charge the battery, The first reactor coil comprises a first reactor coil, one of which is connected to a first node between the two switching elements in the first leg, The AC power is supplied across the other terminal of the first reactor coil and the second node between the two switching elements in the second leg. The inverter has a third leg provided in parallel with the first and second legs, in which a high-side switching element and a low-side switching element are connected in series. A power supply device in which a second reactor coil is provided extending from the second node of the second leg to the third node between the two switching elements in the third leg.

2. The power supply device according to claim 1, wherein the inverter converts the AC power to DC power based on the driving of the switching elements having the first leg and the second leg, and converts the AC power to AC power different from the said AC power based on the driving of the switching elements having the second leg and the third leg.

3. The power supply device according to claim 1 or 2, wherein the phase of the signal that drives the switching element in the third leg is the same as the phase of the AC power input to and output to the first leg and the second leg.

Images