Power source system

Abstract

To provide a power source system capable of suppressing occurrence of UV or OV when switching an operation target for voltage control of a bulk capacitor.SOLUTION: A power source system includes a control device that operates a DC-DC converter and a power converter under any one control mode of a power charging mode, a power feeding mode, and a charging-in-progress power feeding mode. The control device performs bulk voltage control by operating a voltage converter under the power feeding mode, and performs bulk voltage control by operating the power converter under the power charging mode and the charging-in-progress power feeding mode. When switching the control mode between the power feeding mode and the charging-in-progress power feeding mode in response to acquisition of a power charging and feeding request, the control device boosts a bulk voltage by a prescribed width from the time point when the power charging and feeding request is acquired until an operation target of the bulk voltage control is switched between the DC-DC converter and a half PFC circuit of the power converter.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a power supply system, and more particularly to a power supply system capable of simultaneously charging a power storage device from an external power supply connected to an inlet and supplying power to an external load connected to an outlet. [Background technology]

[0002] In recent years, research and development has been conducted into charging and powering mobility vehicles equipped with secondary batteries that contribute to energy efficiency, in order to ensure that more people have access to affordable, reliable, sustainable, and advanced energy.

[0003] Patent Document 1 discloses a vehicle power control device including a storage battery mounted on a vehicle, a charging terminal connectable to an external AC power source, a charging device that converts AC power input from the charging terminal into DC power and charges the storage battery, a discharging terminal connectable to an external AC load, and a power supply device that converts DC power from the storage battery into AC power and outputs it from the discharging terminal. According to the vehicle power control device disclosed in Patent Document 1, by connecting an external AC power source and an AC load to the charging terminal and the discharging terminal, respectively, it is possible to supply power to the AC load while charging the storage battery, thereby improving user convenience. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5578209 Summary of the Invention [Problem to be solved by the invention]

[0005] In order to stably charge the power storage device and supply power to an external load, it is necessary to perform voltage control to maintain the voltage of the bulk capacitor provided in the power circuit connecting the power storage device to the inlet and outlet at a predetermined voltage. Furthermore, such voltage control of the bulk capacitor is often performed by operating various converter circuits connected to the bulk capacitor using a control device.

[0006] In addition, since the flow of power in the power circuit differs between charging and power supply, for example, if you try to start charging while power is being supplied, it is necessary to switch the converter circuit being operated to control the voltage of the bulk capacitor.

[0007] However, when switching the operation target for voltage control in this way, if the period during which voltage control is temporarily stopped is prolonged, a phenomenon called "UV (Under Voltage)" may occur in which the bulk capacitor voltage falls below a predetermined lower threshold. Even if such UV does not occur, a phenomenon called "OV (Over Voltage)" may occur in which the bulk capacitor voltage exceeds a predetermined upper threshold immediately after starting voltage control using a new operation target. If such UV or OV occurs, the control device may determine that an abnormality has occurred in the power circuit and stop the charging and supplying that is being performed, so it is preferable to suppress the occurrence of such UV and OV.

[0008] The present invention aims to provide a power supply system that can suppress the occurrence of UV and OV when switching the operation target for controlling the voltage of a bulk capacitor, thereby contributing to energy efficiency. [Means for solving the problem]

[0009] (1) A power supply system (for example, power supply system 1 described later) according to the present invention includes a power storage device (for example, high-voltage battery B described later), a voltage converter (for example, DC-DC converter 3 described later) connected to the power storage device, an inlet (for example, inlet 4 described later) to which an external power source (for example, external AC power sources EP, EP' described later) can be connected, an outlet (for example, outlet 5 described later) to which an external load (for example, external AC load EL described later) can be connected, a power converter (for example, power converter 6 described later) connected to the inlet and the outlet, a bulk capacitor (for example, bulk capacitor 23 described later) provided on a power line (for example, power lines 21, 22 described later) connecting the voltage converter and the power converter, and a control mode of the voltage converter and the external power source under any one of a charging mode in which the power storage device is charged by the external power source, a power supply mode in which power is supplied to the external load, and a power-during-charging supply mode in which power is supplied to the external load while the power storage device is being charged. and a control device (e.g., control device 8 described later) that operates the power converter, and the control device includes a charging request acquisition unit (e.g., charging / power supply request acquisition unit 81 described later) that acquires a charging request for charging the power storage device or supplying power to the external load, and a charging control unit (e.g., charging control unit 85 described later) that performs voltage control of a bulk voltage, which is a voltage of the bulk capacitor, by operating the voltage converter in the power supply mode, and performs the voltage control by operating the power converter in the charging mode and the charging-in-power supply mode, and is characterized in that, when the control mode is switched between the power supply mode and the charging-in-power supply mode in response to the acquisition of the charging request, the charging control unit increases or decreases the bulk voltage by a predetermined amount from the time when the charging request is acquired until the operation target of the voltage control is switched between the voltage converter and the power converter.

[0010] (2) In this case, the power converter includes a first converter circuit (e.g., a first converter circuit 71 described later) including two or more switching legs (e.g., a first switching leg 61 and a fourth switching leg 64 described later) connected to the power line, a second converter circuit (e.g., a second converter circuit 72 described later) including one or more switching legs (e.g., a second switching leg 62 and a third switching leg 63 described later) connected to the power line so as to be in parallel with the first converter circuit, and a switch circuit (e.g., a switch circuit 65 described later) switchable between a first connection state in which both the first and second converter circuits are connected to the inlet and a second connection state in which the first and second converter circuits are connected to the inlet and the outlet, respectively, and the control device sets the switch circuit to the first connection state in the charging mode and sets the switch circuit to the second connection state in the power supply mode and the power supply during charging mode. a switch control unit (e.g., a switch control unit 84 described later) for switching the control mode to a state in which the charging control unit operates a full PFC circuit constituted by the first and second converter circuits as a PFC converter with the inlet as an input side in the charging mode, and performs the voltage control by operating the voltage converter in the power supply mode, and performs the voltage control by operating a half PFC circuit constituted by the first converter circuit as the PFC converter in the power supply mode during charging. When the control mode is switched between the charging mode and the power supply mode during charging in response to the acquisition of the power supply request, it is preferable that the charging control unit increases or decreases the bulk voltage by a predetermined amount from the time when the power supply request is acquired during the period from when the power supply request is acquired to when the operation target is switched between the full PFC circuit and the half PFC circuit.

[0011] (3) In this case, it is preferable that, in the charging mode, the charge / supply control unit performs the voltage control by operating the full PFC circuit as the PFC converter, and simultaneously performs the charging current control for the power storage device by operating the voltage converter; in the power supply mode, the charge / supply control unit performs the voltage control by operating the voltage converter, and simultaneously performs the power supply current control for the external load by operating the second converter circuit as an inverter with the bulk capacitor as its input side; and, in the charging / power supply mode, the charge / supply control unit performs the voltage control by operating the half PFC circuit as the PFC converter, the power supply current control by operating the second converter circuit as the inverter, and simultaneously performs the charging current control by operating the voltage converter.

[0012] (4) In this case, when the control mode is transitioned from the charging mode to the charging-in-power supply mode, it is preferable that the charging control unit starts operating the second converter circuit as the inverter while continuing to operate the first converter circuit as the PFC converter.

[0013] (5) In this case, when the control mode is transitioned from the power supply mode during charging to the charging mode, it is preferable that the charging control unit starts operating the second converter circuit as the PFC converter while continuing to operate the first converter circuit as the PFC converter.

[0014] (6) In this case, when the control mode is transitioned from the power supply mode to the in-charging power supply mode, it is preferable that the charging and power supply control unit starts operating the first converter circuit as the PFC converter while continuing to operate the second converter circuit as the inverter.

[0015] (7) In this case, when the control mode is transitioned from the charging-in-power supply mode to the power supply mode, it is preferable that the charging and power supply control unit stops operation of the first converter circuit while continuing to operate the second converter circuit as the inverter.

[0016] (8) In this case, when the operation target before and after switching the control mode is defined as a pre-switching operation target and a post-switching operation target, respectively, it is preferable that the charging control unit increases or decreases the bulk voltage by a predetermined amount from the time when the charging request is acquired by operating the pre-switching operation target during the period from when the charging request is acquired to when the operation target is switched from the pre-switching operation target to the post-switching operation target.

[0017] (9) In this case, it is preferable that the control device further includes a target value setting unit (e.g., bulk voltage target value setting unit 86 described below) that sets a bulk voltage target value in the voltage control, the charging control unit operates the operation object so that the bulk voltage becomes the bulk voltage target value in the voltage control, and the target value setting unit increases or decreases the bulk voltage target value by a predetermined offset value from the time when the charging request is acquired until the operation object is switched from the pre-switching operation object to the post-switching operation object after the charging request is acquired.

[0018] (10) In this case, it is preferable that the control device further includes a power supply current acquisition unit (e.g., a power supply current acquisition unit 87 described later) that acquires a power supply current for the external load, and that the target value setting unit changes the offset value in accordance with the power supply current when switching the control mode between the power supply mode and the power supply mode during charging. Effect of the Invention

[0019] (1) In the present invention, the charge / supply request acquisition unit acquires a charge / supply request for charging the power storage device or supplying power to an external load, and the charge / supply control unit performs voltage control of the bulk voltage by operating a voltage converter in the power supply mode, and performs voltage control by operating a power converter in the charging mode and the charging mode. When the charge / supply control unit switches the control mode between the power supply mode and the charging mode in response to the acquisition of the charge / supply request, the charge / supply control unit increases or decreases the bulk voltage by a predetermined amount from the time when the charge / supply request is acquired until the operation target of the voltage control is switched between the voltage converter and the power converter. According to the present invention, the charge / supply control unit increases the bulk voltage by a predetermined amount from the time when the charge / supply request is acquired, thereby suppressing the occurrence of UV. The charge / supply control unit decreases the bulk voltage by a predetermined amount from the time when the charge / supply request is acquired. Therefore, according to the present invention, by suppressing the occurrence of UV and OV when switching control modes, it is possible to prevent the forced stopping of ongoing charging and supply, which ultimately contributes to energy efficiency.

[0020] (2) In the present invention, the switch control unit sets the switch circuit to a first connection state in the charging mode and connects the first and second converter circuits of the power converter to the inlet, and sets the switch circuit to a second connection state in the power supply mode and the power supply during charging mode, connecting the first converter circuit to the inlet and connecting the second converter circuit to the outlet. The charging and power supply control unit performs voltage control by operating a full PFC circuit constituted by the first and second converter circuits as a PFC converter in the charging mode, performs voltage control by operating the voltage converter in the power supply mode, and performs voltage control by operating a half PFC circuit constituted by the first converter circuit as a PFC converter in the power supply mode. Furthermore, when the control mode is switched between the charging mode and the power supply during charging mode, the charging control unit increases or decreases the bulk voltage by a predetermined amount from the time when the charging request is acquired until the target of voltage control is switched between the full PFC circuit and the half PFC circuit, thereby suppressing the occurrence of UV or OV when the control mode is switched.

[0021] (3) According to the present invention, in the charging mode, the charging and supplying control unit performs voltage control by operating the full PFC circuit as a PFC converter, and simultaneously performs charging current control by operating the voltage converter, and in the power supply mode, performs voltage control by operating the voltage converter, and simultaneously performs power supply current control by operating the second converter circuit as an inverter. Also, in the power supply mode during charging, the charging and supplying control unit performs voltage control by operating the half PFC circuit as a PFC converter, performs power supply current control by operating the second converter circuit as an inverter, and simultaneously performs charging current control by operating the voltage converter. According to the present invention, charging, power supply, and power supply during charging can be performed using a common power converter, which can reduce costs compared to the case where charging and power supply are performed using separate units, and can contribute to energy efficiency.

[0022] (4) In the present invention, when the control mode is shifted from the charging mode to the power supply during charging mode, the charging control unit causes only the first converter circuit of the full PFC circuit to continue to operate as a PFC converter while causing the second converter circuit, which had been operating as a PFC converter until then, to start operating as an inverter. As a result, when the control mode is shifted from the charging mode to the power supply during charging mode, it is possible to continue charging the power storage device and start supplying power to the external load while suppressing the occurrence of UV, OV, and the like as described above.

[0023] (5) In the present invention, when the control mode is shifted from the power supply mode during charging to the charging mode, the charging control unit causes the second converter circuit, which had been operating as an inverter, to start operating as a PFC converter while continuing to operate the first converter circuit as a PFC converter. As a result, when the control mode is shifted from the power supply mode during charging to the charging mode, it is possible to continue charging the power storage device and stop power supply to the external load while suppressing the occurrence of UV and OV as described above.

[0024] (6) In the present invention, when the control mode is shifted from the power supply mode to the power supply mode during charging, the charge and supply control unit starts to operate the first converter circuit as a PFC converter while continuing to operate the second converter circuit as an inverter. As a result, when the control mode is shifted from the power supply mode to the power supply mode during charging, it is possible to continue supplying power to the external load and start charging the power storage device while suppressing the occurrence of UV and OV as described above.

[0025] (7) In the present invention, when the control mode is shifted from the power supply mode during charging to the power supply mode, the charge / supply control unit stops the operation of the first converter circuit that had been operating as a PFC converter while continuing to operate the second converter circuit as an inverter. As a result, when the control mode is shifted from the power supply mode during charging to the power supply mode, it is possible to continue supplying power to the external load and stop charging of the power storage device while suppressing the occurrence of UV and OV as described above.

[0026] (8) In the present invention, the charging control unit operates the pre-switching operation object during the period from when the charging request is acquired until the operation object of the voltage control is switched from the pre-switching operation object to the post-switching operation object, thereby increasing the bulk voltage by a predetermined width from the time when the charging request is acquired. This allows the bulk voltage at the time when the voltage control using the pre-switching operation object is stopped to be away from the lower limit threshold at the time of switching the control mode, so that the occurrence of UV can be suppressed from the time when the voltage control using the pre-switching operation object is stopped to the time when the voltage control using the post-switching operation object is started. In addition, the charging control unit operates the pre-switching operation object during the period from when the charging request is acquired until the operation object of the voltage control is switched from the pre-switching operation object to the post-switching operation object, thereby decreasing the bulk voltage by a predetermined width from the time when the charging request is acquired. This allows the bulk voltage at the time when the voltage control using the post-switching operation object is started to be away from the upper limit threshold at the time of switching the control mode, so that the occurrence of OV can be suppressed immediately after the voltage control using the post-switching operation object is started.

[0027] (9) In the present invention, the charging control unit operates the operation target in voltage control so that the bulk voltage becomes the bulk voltage target value set by the target value setting unit, and the target value setting unit increases or decreases the bulk voltage target value by a predetermined offset value from the time when the charging request is acquired until the operation target is switched from the pre-switching operation target to the post-switching operation target after the switching from the time when the charging request is acquired. This makes it possible to suppress the occurrence of UV or OV when switching the control mode.

[0028] (10) When the control mode is switched between the power supply mode and the power charging mode, that is, when power supply to an external load is continued before and after switching of the control mode, the amount of change in the bulk voltage during the temporary suspension of the voltage control differs depending on the magnitude of the power supply current. Therefore, in the present invention, when the control mode is switched between the power supply mode and the power supply during charging mode, the target value setting unit changes the offset value according to the power supply current to the external load. This makes it possible to set the offset value to an appropriate value in anticipation of the change in the bulk voltage during the temporary suspension of the voltage control, thereby more reliably suppressing the occurrence of UV and OV when the control mode is switched between the power supply mode and the power charging mode. [Brief description of the drawings]

[0029] [Figure 1] 1 is a diagram showing the configuration of an electric vehicle equipped with a power supply system according to an embodiment of the present invention; [Diagram 2] 1 is a diagram showing a configuration of a power supply system to which a three-phase, four-wire external AC power supply is connected. [Diagram 3] FIG. 2 is a functional block diagram of a control device. [Figure 4A] FIG. 4 is a diagram illustrating a schematic diagram of a flow of power in a charging mode. [Figure 4B] FIG. 4 is a diagram illustrating a schematic diagram of a flow of power in a power supply mode. [Figure 4C] FIG. 4 is a diagram illustrating a schematic diagram of a flow of power in a charging power supply mode. [Figure 5A] 10 is a flowchart showing a procedure for a control mode determination process (part 1). [Figure 5B] 13 is a flowchart showing the procedure of the control mode determination process (part 2). [Figure 6A] 5 is a time chart showing an example of a control procedure for a power converter and a DC-DC converter during a transitional period when a control mode is shifted from a charging mode to a power supply mode during charging. [Figure 6B]5 is a time chart showing an example of a control procedure for a power converter and a DC-DC converter in a transitional period when a control mode is shifted from a power supply mode during charging to a charging mode. [Figure 6C] 5 is a time chart showing an example of a control procedure for a power converter and a DC-DC converter in a transitional period when the control mode is shifted from a power supply mode to a power supply mode during charging. [Figure 6D] 5 is a time chart showing an example of a control procedure for a power converter and a DC-DC converter in a transitional period when a control mode is shifted from a power supply mode during charging to a power supply mode. [Figure 7] FIG. 13 is a diagram showing an example of a variation pattern determination table. [Figure 8] 11 is a time chart showing an example of control in a case where there is concern about UV generation when transitioning from a power supply mode to a power supply mode during charging. [Figure 9] 6 is a time chart showing an example of control in a case where there is concern about the occurrence of OV when transitioning from a power supply mode to a power supply mode during charging. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A power supply system according to an embodiment of the present invention will now be described with reference to the drawings.

[0031] FIG. 1 is a diagram showing the configuration of a power supply system 1 according to this embodiment and an electric vehicle V (hereinafter, simply referred to as a "vehicle") equipped with this power supply system 1. In this embodiment, the vehicle V is an electric vehicle that runs by supplying power stored in a high-voltage battery B described below to a drive motor (not shown) and rotating drive wheels (not shown), but the present invention is not limited to this. The power supply system according to the present invention is not limited to electric vehicles, and can be applied to any vehicle, such as a hybrid vehicle or a fuel cell vehicle, as long as it is an electric vehicle that runs using power stored in a high-voltage battery B. The power supply system according to the present invention is not limited to the electric vehicles described above, and may be installed in moving objects such as electric motorcycles and electric vertical take-off and landing aircraft (eVTOL).

[0032] The power supply system 1 comprises a high-voltage battery B as a power storage device, a DC-DC converter 3 connected to the high-voltage battery B, an inlet 4 to which an external AC power source EP can be connected, an outlet 5 to which an external AC load EL can be connected, a power converter 6 connected to the inlet 4 and the outlet 5, a pair of power lines 21, 22 connecting the DC-DC converter 3 and the power converter 6, a bulk capacitor 23 connected between the DC-DC converter 3 and the power converter 6 on the power lines 21, 22, and a control device 8 that operates the DC-DC converter 3 and the power converter 6.

[0033] The inlet 4 is connected to a switch circuit 65 (described later) of the power converter 6 via four power lines L1, L2, L3, and N1. The outlet 5 is connected to the switch circuit 65 of the power converter 6 via two power lines L4 and N2.

[0034] As shown in Fig. 1, when a single-phase two-wire external AC power source EP is connected to an inlet 4 via a charging cable C, a voltage line EL1 and a neutral line EN of the external AC power source EP are connected to power lines L1 and N1 extending from the inlet 4, respectively. This allows single-phase AC power to be supplied from the external AC power source EP to the power converter 6 via the power lines L1 and N1. Furthermore, when a single-phase two-wire external AC load EL is connected to the outlet 5, the external AC load EL is connected to the power lines L4 and N2 extending from the outlet 5. This allows single-phase AC power to be supplied from the power converter 6 to the external AC load EL via the power lines L4 and N2.

[0035] In the following, a case where a single-phase two-wire external AC power source EP and an inlet 4 are mainly connected as shown in FIG. 1 will be described, but the present invention is not limited thereto. As shown in FIG. 2, a three-phase four-wire external AC power source EP' and an inlet 4 can also be connected via a charging cable C. In this case, three voltage lines EL1, EL2, EL3 and a neutral line EN of the external AC power source EP' are connected to the power lines L1, L2, L3, and N1 extending from the inlet 4, respectively. This allows three-phase AC power to be supplied from the external AC power source EP' to the power converter 6 via the power lines L1, L2, L3, and N1. Even when a three-phase four-wire external AC power source EP' and an inlet 4 are connected in this way, single-phase AC power can also be supplied from the external AC power source EP' to the power converter 6 by using only the two power lines L1 and N1.

[0036] 1, the high-voltage battery B is a secondary battery capable of both discharging (converting chemical energy into electrical energy) and charging (converting electrical energy into chemical energy). In the following, a case will be described in which a so-called lithium-ion storage battery that charges and discharges by moving lithium ions between electrodes is used as the high-voltage battery B, but the present invention is not limited to this.

[0037] One end of the DC-DC converter 3 is connected to the bulk capacitor 23, and the other end is connected to the high-voltage battery B, and the DC power is stepped up or down between the bulk capacitor 23 and the high-voltage battery B. The DC-DC converter 3 steps up or steps down the DC power in the bulk capacitor 23 and outputs it to the high-voltage battery B, or steps up or steps down the DC power in the high-voltage battery B and outputs it to the bulk capacitor 23, by turning on / off a switching element (not shown) in accordance with a gate drive signal transmitted from the control device 8.

[0038] The power converter 6 comprises four switching legs 61, 62, 63, 64, both ends of which are connected to the power lines 21, 22 so as to be in parallel with the bulk capacitor 23, a switch circuit 65 connecting these switching legs 61 to 64 with an inlet 4 and an outlet 5, a first EMI filter 68 for removing noise in the power lines L1, L2, L3, N1 connecting the inlet 4 and the switch circuit 65, and a second EMI filter 69 for removing noise in the power lines L4, N2 connecting the outlet 5 and the switch circuit 65.

[0039] The first switching leg 61 includes a first upper arm switching element 611 , a first lower arm switching element 612 , and a first choke coil 613 .

[0040] The switching elements 611, 612 include known power switching elements such as MOSFETs and IGBTs that are turned on / off in response to a gate drive signal transmitted from the control device 8, and diodes connected in parallel to the power switching elements. The first upper arm switching element 611 and the first lower arm switching element 612 are connected in series. The drain of the first upper arm switching element 611 is connected to the positive power line 21, the source of the first upper arm switching element 611 is connected to the drain of the first lower arm switching element 612, and the source of the first lower arm switching element 612 is connected to the negative power line 22. One end of the first choke coil 613 is connected to a connection point between the first upper arm switching element 611 and the first lower arm switching element 612, and the other end is connected to the switch circuit 65.

[0041] The second switching leg 62 includes a second upper arm switching element 621 , a second lower arm switching element 622 , and a second choke coil 623 .

[0042] The switching elements 621, 622 include known power switching elements such as MOSFETs and IGBTs that are turned on / off in response to a gate drive signal transmitted from the control device 8, and diodes connected in parallel to the power switching elements. The second upper arm switching element 621 and the second lower arm switching element 622 are connected in series. The drain of the second upper arm switching element 621 is connected to the positive power line 21, the source of the second upper arm switching element 621 is connected to the drain of the second lower arm switching element 622, and the source of the second lower arm switching element 622 is connected to the negative power line 22. One end of the second choke coil 623 is connected to a connection point between the second upper arm switching element 621 and the second lower arm switching element 622, and the other end is connected to the switch circuit 65.

[0043] The third switching leg 63 includes a third upper arm switching element 631 , a third lower arm switching element 632 , and a third choke coil 633 .

[0044] The switching elements 631 and 632 include known power switching elements such as MOSFETs and IGBTs that are turned on / off in response to a gate drive signal transmitted from the control device 8, and diodes connected in parallel to the power switching elements. The third upper arm switching element 631 and the third lower arm switching element 632 are connected in series. The drain of the third upper arm switching element 631 is connected to the positive power line 21, the source of the third upper arm switching element 631 is connected to the drain of the third lower arm switching element 632, and the source of the third lower arm switching element 632 is connected to the negative power line 22. One end of the third choke coil 633 is connected to a connection point between the third upper arm switching element 631 and the third lower arm switching element 632, and the other end is connected to the switch circuit 65.

[0045] The fourth switching leg 64 includes a fourth upper arm switching element 641 , a fourth lower arm switching element 642 , and a fourth choke coil 643 .

[0046] The switching elements 641, 642 include known power switching elements such as MOSFETs and IGBTs that are turned on / off in response to a gate drive signal transmitted from the control device 8, and diodes connected in parallel to the power switching elements. The fourth upper arm switching element 641 and the fourth lower arm switching element 642 are connected in series. The drain of the fourth upper arm switching element 641 is connected to the positive power line 21, the source of the fourth upper arm switching element 641 is connected to the drain of the fourth lower arm switching element 642, and the source of the fourth lower arm switching element 642 is connected to the negative power line 22. One end of the fourth choke coil 643 is connected to a connection point between the fourth upper arm switching element 641 and the fourth lower arm switching element 642, and the other end is connected to the switch circuit 65.

[0047] In the following, a circuit combining the first switching leg 61 and the fourth switching leg 64 connected to the power lines 21, 22 so as to be in parallel with the bulk capacitor 23 is referred to as a first converter circuit 71. A circuit combining the second switching leg 62 and the third switching leg 63 connected to the power lines 21, 22 so as to be in parallel with the first converter circuit 71 is referred to as a second converter circuit 72. In the following, the first and second converter circuits 71 and 72 that operate as PFC converters in a charging mode described later are also collectively referred to as a "full PFC circuit." In addition, the first converter circuit 71 that operates as a PFC converter in a charging power supply mode described later is also referred to as a "half PFC circuit" to mean half of the full PFC circuit.

[0048] The switch circuit 65 is a circuit that connects choke coils 613, 623, 633, and 643, which are input / output terminals of the four switching legs 61, 62, 63, and 64, to a total of six power lines L1, L2, L3, L4, N1, and N2. The switch circuit 65 includes a first relay 66 and a second relay 67 that operate in response to a command signal from the control device 8.

[0049] As shown in FIG. 1, the switch circuit 65 constantly connects the first choke coil 613 of the first switching leg 61 to the power line L1 connected to the inlet 4, and constantly connects the fourth choke coil 643 of the fourth switching leg 64 to the power line N1 connected to the inlet 4.

[0050] In response to a command signal from the control device 8, the first relay 66 can be switched between three states: a state in which the second choke coil 623 of the second switching leg 62 is connected to the power line L1 extending from the inlet 4, a state in which the second choke coil 623 is connected to the power line L2 extending from the inlet 4, and a state in which the second choke coil 623 is connected to the power line L4 extending from the outlet 5.

[0051] In response to a command signal from the control device 8, the second relay 67 can be switched between three states: a state in which the third choke coil 633 of the third switching leg 63 is connected to the power line N1 extending from the inlet 4, a state in which it is connected to the power line L3 extending from the inlet 4, and a state in which it is connected to the power line N2 extending from the outlet 5.

[0052] The switch circuit 65 is configured by combining the two three-state relays 66, 67 as described above, and is therefore capable of realizing a total of nine connection states.

[0053] In the following, a state in which the second choke coil 623 of the second switching leg 62 and the power line L1 extending from the inlet 4 are connected by the first relay 66, and the third choke coil 633 of the third switching leg 63 and the power line N1 extending from the inlet 4 are connected by the second relay 67, that is, a state in which both the first converter circuit 71 and the second converter circuit 72 are connected to the inlet 4, is referred to as a first connection state. More specifically, in this first connection state, the first choke coil 613 of the first switching leg 61 and the second choke coil 623 of the second switching leg 62 are connected to a common power line L1, and the third choke coil 633 of the third switching leg 63 and the fourth choke coil 643 of the fourth switching leg 64 are connected to a common power line N1.

[0054] Furthermore, the state in which the first relay 66 connects the second choke coil 623 of the second switching leg 62 and the power line L4 extending from the outlet 5, and the second relay 67 connects the third choke coil 633 of the third switching leg 63 and the power line N2 extending from the outlet 5, i.e., the state in which the first converter circuit 71 and the second converter circuit 72 are connected to the inlet 4 and the outlet 5, respectively, is called the second connection state.

[0055] Furthermore, a state in which the first relay 66 connects the second choke coil 623 of the second switching leg 62 and the power line L2 extending from the inlet 4, and the second relay 67 connects the third choke coil 633 of the third switching leg 63 and the power line L3 extending from the inlet 4 is called a third connection state.

[0056] As described above, in this embodiment, the switch circuit 65 is configured by combining two relays 66, 67 that can be switched between three states, but the present invention is not limited to this. The switch circuit 65 is not limited to the three-state relays 66, 67, and may use any known switching means such as a two-state relay or switch, as long as it can realize the above-mentioned multiple connection states.

[0057] FIG. 3 is a functional block diagram of a control device 8 that operates the DC-DC converter 3 and the power converter 6 described above.

[0058] The control device 8 includes a charging / power supply request acquisition unit 81 that acquires a request for charging by the external AC power source EP or power supply to the external AC load EL, an operation state information acquisition unit 82 that acquires operation state information related to the operation states of the power converter 6 and the DC-DC converter 3, a control mode determination unit 83 that determines a control mode for the power converter 6 and the DC-DC converter 3 by the control device 8, a switch control unit 84 that operates the switch circuit 65 of the power converter 6 in a manner determined by the determined control mode, a charging and supplying control unit 85 that operates the power converter 6 and the DC-DC converter 3 in a manner determined by the determined control mode, a bulk voltage target value setting unit 86 that sets a bulk voltage target value in bulk voltage control by the charging and supplying control unit 85, which will be described later, a power supply current acquisition unit 87 that acquires a power supply current supplied to the external AC load EL, and an abnormality determination unit 88 that determines the presence or absence of an abnormality in the power supply system 1.

[0059] As will be described later with reference to Figures 4A and 4C, when the power supply system 1 is connected to the external AC power supply EP and the inlet 4, it is capable of charging the high-voltage battery B with AC power supplied from the external AC power supply EP. Also, as will be described later with reference to Figures 4B and 4C, when the power supply system 1 is connected to the external AC load EL and the outlet 5, it is capable of supplying power to the external AC load EL by utilizing the DC power in the bulk capacitor 23.

[0060] Therefore, the charging / power supply request acquisition unit 81 acquires a request for charging by the external AC power source EP or for power supply to the external AC load EL. Hereinafter, a request for starting charging by the external AC power source EP is referred to as a charging start request, and a request for stopping charging by the external AC power source EP is referred to as a charging stop request. Also, a request for starting power supply to the external AC load EL is referred to as a power supply start request, and a request for stopping power supply to the external AC load EL is referred to as a power supply stop request. Hereinafter, the charging start request, charging stop request, power supply start request, and power supply stop request acquired by the charging / power supply request acquisition unit 81 are collectively referred to as "charging / power supply requests."

[0061] The charging / power supply request acquisition unit 81 acquires a charging start request, for example, when the external AC power source EP and the inlet 4 are connected via the charging cable C based on an operation by a user. After starting charging from the external AC power source EP, the charging / power supply request acquisition unit 81 acquires a charging stop request, for example, when the remaining charge of the high-voltage battery B exceeds a predetermined amount or when a predetermined charging stop operation by the user is detected.

[0062] The charging / power supply request acquisition unit 81 acquires a power supply start request, for example, when the external AC load EL and the outlet 5 are connected and a predetermined power supply start operation by the user is detected for a power supply interface (for example, a power supply interface switch mounted on the vehicle or a smartphone owned by the user). After starting power supply to the external AC load EL, the charging / power supply request acquisition unit 81 acquires a power supply stop request, for example, when a predetermined power supply stop operation by the user is detected for the power supply interface.

[0063] Control mode determination unit 83 determines the control mode of power converter 6 and DC-DC converter 3 to be performed by control units 84, 85 described below. As will be described below with reference to Figures 4A to 4C, control units 84, 85 are capable of operating power converter 6 and DC-DC converter 3 in any one of three control modes consisting of a charging mode (see Figure 4A), a power supply mode (see Figure 4B), and a power supply during charging mode (see Figure 4C), in which the flows of power in power converter 6 and DC-DC converter 3 are different.

[0064] FIG. 4A is a diagram showing a schematic diagram with dashed arrows illustrating the flow of power when control units 84, 85 operate power converter 6 and DC-DC converter 3 in the charging mode.

[0065] In the charging mode, the switch control unit 84 operates the relays 66, 67 of the switch circuit 65 to set the switch circuit 65 to the first connection state. As a result, the first converter circuit 71 and the second converter circuit 72 are both connected to the power lines L1, N1 of the inlet 4.

[0066] Furthermore, in order to realize the flow of power as shown in FIG. 4A and charge the high-voltage battery B with power supplied from the external AC power supply EP, the charging / power supply control unit 85 simultaneously performs bulk voltage control, which controls the bulk voltage, which is the voltage of the bulk capacitor 23, to a bulk voltage target value described below, and charging current control, which controls the charging current supplied to the high-voltage battery B to a predetermined charging current target value.

[0067] More specifically, in the charging mode, the charging control unit 85 performs bulk voltage control by setting the full PFC circuit constituted by the first converter circuit 71 and the second converter circuit 72 as an operation target in the bulk voltage control and operating this operation target as a PFC converter with the inlet 4 as an input side. More specifically, in the charging mode, the charging control unit 85 operates the full PFC circuit so that the full PFC circuit operates as a PFC converter with the inlet 4 as an AC input side and the bulk capacitor 23 as a DC output side. That is, the charging control unit 85 operates the full PFC circuit so that AC power input from the external AC power source EP connected to the inlet 4 is converted into DC power in the full PFC circuit and the power factor approaches 1. At this time, the charging control unit 85 operates the full PFC circuit as a PFC converter so that the bulk voltage becomes a bulk voltage target value set by a bulk voltage target value setting unit 86 described later.

[0068] In addition, in the charging mode, the charging control unit 85 performs bulk voltage control by operating the full PFC circuit as a PFC converter as described above, and at the same time performs charging current control for the high-voltage battery B by operating the DC-DC converter 3.

[0069] In the charging mode, the control units 84, 85 operate the power converter 6 and the DC-DC converter 3 as described above to charge the high-voltage battery B with AC power supplied from the external AC power source EP connected to the inlet 4.

[0070] FIG. 4B is a diagram showing a schematic diagram with dashed arrows illustrating the flow of power when control units 84, 85 operate power converter 6 and DC-DC converter 3 in the power supply mode.

[0071] In the power supply mode, the switch control unit 84 operates the relays 66, 67 of the switch circuit 65 to set the switch circuit 65 to the second connection state. This connects the second converter circuit 72 to the power lines L4, N2 of the outlet 5.

[0072] In addition, in order to realize the flow of power as shown in FIG. 4B and supply power to the external AC load EL with power from the high-voltage battery B, the charging / supply control unit 85 simultaneously performs bulk voltage control for controlling the bulk voltage to a bulk voltage target value, and supply current control for controlling the supply current supplied to the external AC load EL to a predetermined supply current target value.

[0073] More specifically, in the power supply mode, the charging / supply control unit 85 performs bulk voltage control by controlling the DC-DC converter 3 as an operation object in the bulk voltage control so that DC power from the high-voltage battery B is supplied to the bulk capacitor 23. That is, the charging / supply control unit 85 operates the DC-DC converter 3 so that the bulk voltage becomes a bulk voltage target value set by a bulk voltage target value setting unit 86 described later.

[0074] In addition, in the power supply mode, the charging and supplying control unit 85 performs bulk voltage control by operating the DC-DC converter 3 as described above, and at the same time performs power supply current control to the external AC load EL by operating the second converter circuit 72 as an inverter with the bulk capacitor 23 as its input side.

[0075] In the power supply mode, the control units 84, 85 operate the power converter 6 and the DC-DC converter 3 as described above to convert the DC power supplied from the high-voltage battery B into AC power and supply it to the external AC load EL connected to the outlet 5.

[0076] FIG. 4C is a diagram showing a schematic diagram with dashed arrows illustrating the flow of power when control units 84, 85 operate power converter 6 and DC-DC converter 3 in the power supply during charging mode.

[0077] In the charging power supply mode, the switch control unit 84 operates the relays 66, 67 of the switch circuit 65 to set the switch circuit 65 to the second connection state. As a result, the first converter circuit 71 is connected to the power lines L1, N1 of the inlet 4, and the second converter circuit 72 is connected to the power lines L4, N2 of the outlet 5.

[0078] Furthermore, in order to realize the flow of power as shown in FIG. 4C and supply power to the external AC load EL while charging the high-voltage battery B, the charging / supply control unit 85 simultaneously performs bulk voltage control for controlling the bulk voltage to a bulk voltage target value, power supply current control for controlling the power supply current supplied to the external AC load EL to a power supply current target value, and charging current control for controlling the charging current supplied to the high-voltage battery B to a charging current target value.

[0079] More specifically, in the charging power supply mode, the charging power supply control unit 85 performs bulk voltage control by setting the half PFC circuit constituted by the first converter circuit 71 as an operation target in the bulk voltage control and operating this operation target as a PFC converter with the inlet 4 as an input side. More specifically, in the charging power supply mode, the charging power supply control unit 85 operates the half PFC circuit so that the half PFC circuit operates as a PFC converter with the inlet 4 as an AC input side and the bulk capacitor 23 as a DC output side. That is, the charging power supply control unit 85 operates the half PFC circuit so that AC power input from the external AC power source EP connected to the inlet 4 is converted into DC power in the half PFC circuit and the power factor approaches 1. At this time, the charging power supply control unit 85 operates the half PFC circuit as a PFC converter so that the bulk voltage becomes a bulk voltage target value set by a bulk voltage target value setting unit 86 described later.

[0080] In addition, in the charging power supply mode, the charge and supply control unit 85 performs bulk voltage control by operating the half PFC circuit as a PFC converter as described above, performs power supply current control to the external AC load EL by operating the second converter circuit 72 as an inverter as in the power supply mode, and simultaneously performs charging current control by operating the DC-DC converter 3 as in the charging mode.

[0081] In the power supply during charging mode, the control units 84, 85 operate the power converter 6 and the DC-DC converter 3 in the above-described manner to charge the high-voltage battery B with AC power supplied from the external AC power source EP connected to the inlet 4, while converting the DC power in the bulk capacitor 23 into AC power and supplying it to the external AC load EL connected to the outlet 5.

[0082] Returning to Fig. 3, the operation state information acquisition unit 82 acquires operation state information indicating the current operation states of the power converter 6 and the DC-DC converter 3 based on information transmitted from the control units 84, 85. The operation state information acquisition unit 82 transmits the acquired operation state information to the control mode determination unit 83. By referring to the operation state information transmitted from the operation state information acquisition unit 82, the control mode determination unit 83 can determine whether the operation states of the power converter 6 and the DC-DC converter 3 are operating in a charging mode (hereinafter referred to as a "charging state"), operating in a power supply mode (hereinafter referred to as a "power supply state"), operating in a power supply mode during charging (hereinafter referred to as a "power supply state during charging"), or in a stopped state.

[0083] When a charge / power supply request for charging or power supply is acquired by the charge / power supply request acquisition unit 81, the control mode determination unit 83 determines the control mode to be used by the control units 84, 85 based on the operation status information transmitted from the operation status information acquisition unit 82 and the type of the acquired charge / power supply request.

[0084] 5A and 5B are flowcharts showing specific steps of a control mode determination process for determining a control mode in the control mode determination unit 83. The control mode determination process shown in Fig. 5A and 5B is executed by the control mode determination unit 83 when the charge / power supply request acquisition unit 81 acquires any charge / power supply request.

[0085] First, in step ST1, the control mode determination unit 83 determines whether the current operation state is a stopped state by referring to the operation state information. If the determination result in step ST1 is YES, the control mode determination unit 83 proceeds to step ST2, and if the determination result is NO, the control mode determination unit 83 proceeds to step ST11.

[0086] In step ST2, the control mode determination unit 83 determines whether or not a charging start request has been acquired. If the determination result in step ST2 is YES, that is, if a charging start request has been acquired, the control mode determination unit 83 proceeds to step ST3. If the determination result in step ST2 is NO, that is, if a power supply start request has been acquired, the control mode determination unit 83 proceeds to step ST4.

[0087] In step ST3, the control mode determination unit 83 determines the charging mode as the control mode, and then ends the control mode determination process. As a result, the control units 84 and 85 start operating the power converter 6 and the DC-DC converter 3 according to the procedure described with reference to Fig. 4A. As a result, the operation states of the power converter 6 and the DC-DC converter 3 transition from the stopped state to the charging state.

[0088] In step ST4, the control mode determination unit 83 determines the power supply mode as the control mode, and then ends the control mode determination process. As a result, the control units 84 and 85 start operating the power converter 6 and the DC-DC converter 3 according to the procedure described with reference to Fig. 4B. As a result, the operation states of the power converter 6 and the DC-DC converter 3 transition from the stopped state to the power supply state.

[0089] In step ST11, the control mode determination unit 83 determines whether the current operation state is a charging state by referring to the operation state information. If the determination result in step ST11 is YES, the control mode determination unit 83 proceeds to step ST12, and if the determination result is NO, the control mode determination unit 83 proceeds to step ST21.

[0090] In step ST12, the control mode determination unit 83 determines whether or not a charging stop request has been acquired. If the determination result in step ST12 is YES, that is, if a charging stop request has been acquired, the control mode determination unit 83 proceeds to step ST13. If the determination result in step ST12 is NO, that is, if a power supply start request has been acquired, the control mode determination unit 83 proceeds to step ST14.

[0091] In step ST13, the control mode determination unit 83 ends the control mode determination process after stopping the charging mode. As a result, the control units 84 and 85 stop the operation of the power converter 6 and the DC-DC converter 3. As a result, the operation states of the power converter 6 and the DC-DC converter 3 transition from the charging state to the stopped state.

[0092] In step ST14, the control mode determination unit 83 transitions the control mode from the charging mode to the charging power supply mode, and then ends the control mode determination process. As a result, the control units 84 and 85 start operating the power converter 6 and the DC-DC converter 3 according to the procedure described with reference to Fig. 4C. As a result, the operation states of the power converter 6 and the DC-DC converter 3 transition from the charging state to the charging power supply state.

[0093] In step ST21, the control mode determination unit 83 judges whether the current operation state is a power supply state by referring to the operation state information. If the judgment result in step ST21 is YES, the control mode determination unit 83 proceeds to step ST22. If the judgment result in step ST21 is NO, that is, if the current operation state is a charging power supply state, the control mode determination unit 83 proceeds to step ST31.

[0094] In step ST22, the control mode determination unit 83 determines whether or not a power supply stop request has been acquired. If the determination result in step ST22 is YES, that is, if a power supply stop request has been acquired, the control mode determination unit 83 proceeds to step ST23. If the determination result in step ST22 is NO, that is, if a charging start request has been acquired, the control mode determination unit 83 proceeds to step ST24.

[0095] In step ST23, the control mode determination unit 83 ends the control mode determination process after stopping the power supply mode. As a result, the control units 84 and 85 stop the operation of the power converter 6 and the DC-DC converter 3. As a result, the operation states of the power converter 6 and the DC-DC converter 3 transition from the power supply state to the stopped state.

[0096] In step ST24, the control mode determination unit 83 transitions the control mode from the power supply mode to the charging-time power supply mode, and then ends the control mode determination process. As a result, the control units 84 and 85 start operating the power converter 6 and the DC-DC converter 3 according to the procedure described with reference to Fig. 4C. As a result, the operation states of the power converter 6 and the DC-DC converter 3 transition from the power supply state to the charging-time power supply state.

[0097] In step ST31, the control mode determination unit 83 judges whether or not a charging stop request has been acquired. If the judgment result in step ST31 is YES, that is, if a charging stop request has been acquired, the control mode determination unit 83 proceeds to step ST32. If the judgment result in step ST31 is NO, that is, if a power supply stop request has been acquired, the control mode determination unit 83 proceeds to step ST33.

[0098] In step ST32, the control mode determination unit 83 transitions the control mode from the charging power supply mode to the power supply mode, and then ends the control mode determination process. As a result, the control units 84 and 85 start operating the power converter 6 and the DC-DC converter 3 according to the procedure described with reference to Fig. 4B. As a result, the operation states of the power converter 6 and the DC-DC converter 3 transition from the charging power supply state to the power supply state.

[0099] In step ST33, the control mode determination unit 83 transitions the control mode from the charging power supply mode to the charging mode, and then ends the control mode determination process. As a result, the control units 84 and 85 start operating the power converter 6 and the DC-DC converter 3 according to the procedure described with reference to Fig. 4A. As a result, the operation state of the power converter 6 and the DC-DC converter 3 transitions from the charging power supply state to the charging state.

[0100] Next, an example of a control procedure of power converter 6 and DC-DC converter 3 by control device 8 during a transitional period when switching control modes will be described with reference to the time charts shown in FIGS. 6A to 6D.

[0101] Fig. 6A is a time chart showing an example of a control procedure for the power converter 6 and the DC-DC converter 3 in a transitional period when the control mode is shifted from the charging mode to the charging power supply mode (see step ST14 in Fig. 5A). Fig. 6A also shows a case where a power supply start request is acquired at time t1 while the high-voltage battery B is being charged in the charging mode.

[0102] 6A, the control mode determination unit 83 starts to shift the control mode from the charging mode to the charging power supply mode in response to the acquisition of a power supply start request at time t1. Also, at the time when the power supply start request is acquired at time t1, the control mode is the charging mode. Therefore, at time t1, the charging power supply control unit 85 performs bulk voltage control by controlling the full PFC circuit constituted by the first converter circuit 71 and the second converter circuit 72 as the operation target, and at the same time, performs charging current control by operating the DC-DC converter 3.

[0103] After that, at time t2, the charging control unit 85 stops the function of the second converter circuit 72 that had been operating as a PFC converter while continuing to operate only the first converter circuit 71 of the full PFC circuit as a PFC converter. In other words, at time t2, the charging control unit 85 switches the operation target of the bulk voltage control from the full PFC circuit to the half PFC circuit.

[0104] Then, at time t3, the charging / power supply control unit 85 starts to operate the second converter circuit 72 as an inverter while continuing to operate the half PFC circuit as a PFC converter. Then, at time t4, stable AC power starts to be supplied from the second converter circuit 72 operating as an inverter to the external AC load EL connected to the outlet 5. As a result, at time t4, the transition from the charging mode to the power supply mode during charging is completed.

[0105] As described above, when the control device 8 acquires a power supply start request while the high-voltage battery B is being charged in the charging mode, the control device 8 starts to operate the second converter circuit 72 as an inverter while continuing to operate the first converter circuit 71 as a PFC converter, thereby shifting the control mode from the charging mode to the power supply mode during charging. This allows the charging of the high-voltage battery B to continue even while the operating state of the second converter circuit 72 is switching between times t1 and t4.

[0106] Fig. 6B is a time chart showing a detailed control procedure of the power converter 6 and the DC-DC converter 3 in a transitional period when the control mode is shifted from the power supply mode during charging to the charging mode (see step ST33 in Fig. 5B). Fig. 6B also shows a case where a power supply stop request is acquired at time t11 while power is being supplied to the external AC load EL while the high-voltage battery B is being charged in the power supply mode during charging.

[0107] In the example shown in Fig. 6B, the control mode determination unit 83 starts to shift the control mode from the charging power supply mode to the charging mode in response to the acquisition of a power supply stop request at time t11. Also, at the time when the power supply stop request is acquired at time t11, the control mode is the charging power supply mode. Therefore, at time t11, the charging power supply control unit 85 performs bulk voltage control with the half PFC circuit constituted only by the first converter circuit 71 as the operation target, and at the same time, performs charging current control by operating the DC-DC converter 3. At the same time, the charging power supply control unit 85 operates the second converter circuit 72 as an inverter to perform power supply current control for the external AC load EL.

[0108] After that, at time t12, the charging / power supply control unit 85 stops the function of the second converter circuit 72 that had been operating as an inverter while continuing to operate the half PFC circuit as a PFC converter, thereby stopping the power supply to the external AC load EL after time t12.

[0109] After that, at time t13, the charging control unit 85 starts to operate the second converter circuit 72 as a PFC converter while continuing to operate the first converter circuit 71 as a PFC converter. In other words, the charging control unit 85 switches the operation target of the bulk voltage control from the half PFC circuit to the full PFC circuit at time t13. As a result, the transition from the power supply mode during charging to the charging mode is completed at time t13.

[0110] As described above, when the control device 8 acquires a power supply stop request while supplying power to the external AC load EL while charging the high-voltage battery B in the charging power supply mode, the control mode is shifted from the charging power supply mode to the charging mode by starting to operate the second converter circuit 72 as a PFC converter while continuing to operate the first converter circuit 71 as a PFC converter. This allows the charging of the high-voltage battery B to continue even while the operation state of the second converter circuit 72 is switching between times t11 and t13.

[0111] Fig. 6C is a time chart showing an example of a control procedure of the power converter 6 and the DC-DC converter 3 in a transitional period when the control mode is shifted from the power supply mode to the charging power supply mode (see step ST24 in Fig. 5B). Fig. 6C also shows a case where a charge start request is acquired at time t21 while power is being supplied to the external AC load EL in the power supply mode.

[0112] 6C, the control mode determination unit 83 starts to shift the control mode from the power supply mode to the during-charging power supply mode in response to the acquisition of a charge start request at time t21. Also, at the time when the charge start request is acquired at time t21, the control mode is the power supply mode. Therefore, at time t21, the charging power supply control unit 85 performs bulk voltage control with the DC-DC converter 3 as the operation target, and simultaneously performs power supply current control to the external AC load EL by operating the second converter circuit 72 as an inverter.

[0113] After that, at time t22, the charging control unit 85 stops the operation of the DC-DC converter 3 while continuing to operate the second converter circuit 72 as an inverter. That is, at time t22, the charging control unit 85 stops the bulk voltage control that operates the DC-DC converter 3. When the bulk voltage control is stopped in this manner, the bulk voltage starts to drop after time t22, but the charging control unit 85 performs the power supply current control by operating the second converter circuit 72 as an inverter, so that it is possible to temporarily continue power supply to the external AC load EL.

[0114] After that, at time t23, the charging control unit 85 starts the bulk voltage control with the half PFC circuit (i.e., the first converter circuit 71) that had been stopped as the operation target, while continuing to operate the second converter circuit 72 as an inverter. In other words, at time t23, the charging control unit 85 switches the operation target of the bulk voltage control from the DC-DC converter 3 to the half PFC circuit.

[0115] After that, at time t24, the charging / power supply control unit 85 operates the DC-DC converter 3 to start charging current control for the high-voltage battery B. As a result, at time t24, charging current starts to be supplied to the high-voltage battery B. As a result, at time t24, the transition from the power supply mode to the power supply mode during charging is completed.

[0116] As described above, when the control device 8 acquires a charge start request while power is being supplied to the external AC load EL in the power supply mode, the control device 8 starts to operate the first converter circuit 71 as a PFC converter while continuing to operate the second converter circuit 72 as an inverter, thereby shifting the control mode from the power supply mode to the charging-in-power supply mode. This makes it possible to continue supplying power to the external AC load EL even while the operating states of the DC-DC converter 3 and the first converter circuit 71 are switching between times t21 and t24.

[0117] Fig. 6D is a time chart showing an example of a control procedure of the power converter 6 and the DC-DC converter 3 in a transitional period when the control mode is shifted from the power supply mode during charging to the charging mode (see step ST32 in Fig. 5B). Fig. 6D also shows a case where a charge stop request is acquired at time t31 while the high-voltage battery B is being charged and power is being supplied to the external AC load EL in the power supply mode during charging.

[0118] In the example shown in Fig. 6D, the control mode determination unit 83 starts to shift the control mode from the charging power supply mode to the power supply mode in response to the acquisition of a charging stop request at time t31. Also, at the time when the charging stop request is acquired at time t31, the control mode is the charging power supply mode. Therefore, at time t31, the charging power supply control unit 85 performs bulk voltage control with the half PFC circuit constituted only by the first converter circuit 71 as the operation target, and at the same time, performs charging current control by operating the DC-DC converter 3. At the same time, the charging power supply control unit 85 operates the second converter circuit 72 as an inverter to perform power supply current control for the external AC load EL.

[0119] After that, at time t32, the charging control unit 85 stops the function of the DC-DC converter 3 while continuing to operate the second converter circuit 72 as an inverter, thereby stopping the charging of the high-voltage battery B.

[0120] After that, at time t33, the charging control unit 85 stops the function of the first converter circuit 71 while continuing to operate the second converter circuit 72 as an inverter. That is, at time t33, the charging control unit 85 stops the bulk voltage control that operates the half PFC circuit. When the bulk voltage control is stopped in this way, the bulk voltage starts to drop after time t33, but the charging control unit 85 performs the power supply current control by operating the second converter circuit 72 as an inverter, so that power supply to the external AC load EL can be temporarily continued.

[0121] After that, at time t34, the charging control unit 85 starts the bulk voltage control with the DC-DC converter 3 as the operation target. In other words, at time t34, the charging control unit 85 switches the operation target of the bulk voltage control from the half PFC circuit to the DC-DC converter 3. As a result, at time t34, the transition from the charging power supply mode to the power supply mode is completed.

[0122] As described above, when the control device 8 acquires a charge stop request while feeding power to the external AC load EL while charging the high-voltage battery B in the charging power supply mode, the control mode is shifted from the charging power supply mode to the power supply mode by stopping the operation of the first converter circuit 71 while continuing to operate the second converter circuit 72 as an inverter. This makes it possible to continue feeding power to the external AC load EL during the period from time t31 to t34 while the operating states of the DC-DC converter 3 and the first converter circuit 71 are being switched.

[0123] Returning to FIG. 3, the power supply current acquisition unit 87 acquires the power supply current to the external AC load EL by using a current sensor (not shown) while power is being supplied to the external AC load EL in the power supply mode and the power supply during charging mode.

[0124] The abnormality determination unit 88 detects the presence or absence of an abnormality in the power supply system 1 by monitoring the bulk voltage while charging or power supply is being performed under the control of the control units 84 and 85. More specifically, if the bulk voltage acquired using a voltage sensor not shown while charging or power supply is being performed falls below a predetermined lower limit threshold (see Figs. 8 and 9, etc. described later) (i.e., if UV occurs) or if the bulk voltage exceeds a predetermined upper limit threshold (see Figs. 8 and 9, etc. described later) (i.e., if OV occurs), the abnormality determination unit 88 determines that some abnormality has occurred in the power supply system 1 and stops the bulk voltage control, charging current control, power supply current control, etc. being performed in the charging and power supply control unit 85.

[0125] The bulk voltage target value setting unit 86 sets the bulk voltage target value in the above-mentioned bulk voltage control to a magnitude determined for each control mode within a range between a lower threshold value and an upper threshold value.

[0126] Incidentally, when the control mode is switched between the power supply mode and the power supply during charging mode (see FIGS. 6C and 6D) or when the control mode is switched between the charging mode and the power supply during charging mode (see FIGS. 6A and 6B), the charging and power supply control unit 85 needs to switch the operation target of the bulk voltage control. That is, when the control mode is switched between the power supply mode and the power supply during charging mode, the operation target of the bulk voltage control needs to be switched between the DC-DC converter 3 and the half PFC circuit (i.e., the first converter circuit 71), and when the control mode is switched between the charging mode and the power supply during charging mode, the operation target of the bulk voltage control needs to be switched between the full PFC circuit (i.e., the first converter circuit 71 and the second converter circuit 72) and the half PFC circuit.

[0127] In this embodiment, the operation target of the bulk voltage control before and after switching the control mode is defined as a pre-switching operation target and a post-switching operation target, respectively. That is, when the control mode is switched from the power supply mode to the charging mode (see FIG. 6C), the pre-switching operation target is the DC-DC converter 3 and the post-switching operation target is the half PFC circuit, and when the control mode is switched from the charging mode to the power supply mode (see FIG. 6D), the pre-switching operation target is the half PFC circuit and the post-switching operation target is the DC-DC converter 3. When the control mode is switched from the charging mode to the charging mode (see FIG. 6A), the pre-switching operation target is the full PFC circuit and the post-switching operation target is the half PFC circuit, and when the control mode is switched from the charging mode to the charging mode (see FIG. 6B), the pre-switching operation target is the half PFC circuit and the post-switching operation target is the full PFC circuit.

[0128] As described above, since the operation target of the bulk voltage control needs to be switched when the control mode is switched, the bulk voltage control by the power supply control unit 85 may be temporarily stopped when the control mode is switched (see times t22 to t23 in FIG. 6C and t33 to t34 in FIG. 6D). If such a suspension period of the bulk voltage control is set long, the charge of the bulk capacitor 23 may be discharged during that time, causing the bulk voltage to drop significantly and fall below the lower limit threshold, and the abnormality determination unit 88 may determine that an abnormality has occurred. In other words, if the suspension period of the bulk voltage control when the control mode is switched is set long, there is a concern that UV may occur.

[0129] Furthermore, if the suspension period of the bulk voltage control is set to be short, the above-mentioned UV is less likely to occur, but immediately after the charging control unit 85 starts the bulk voltage control by operating the post-switching operation target, the bulk voltage may overshoot the bulk voltage target value. For this reason, immediately after the start of the bulk voltage control, the bulk voltage may exceed the upper limit threshold, and the abnormality determination unit 88 may determine that an abnormality has occurred. Note that the amount of overshoot of the bulk voltage immediately after the start of such bulk voltage control largely depends on the circuit configuration of the post-switching operation target, the bulk voltage control settings in the charging control unit 85, and the like. For these reasons, there may be cases where the occurrence of OV is a concern.

[0130] As described above, when switching control modes, there is concern about the occurrence of either UV or OV. Furthermore, as described above, whether UV or OV is a concern largely depends on the circuit configuration and control settings. Furthermore, whether UV or OV is a concern may differ depending on the control mode switching scene. Furthermore, the fluctuation range of the bulk voltage when switching control modes may also differ depending on the control mode switching scene.

[0131] Therefore, in order to suppress UV or OV when the control mode is switched as described above, the bulk voltage target value setting unit 86 raises or lowers the bulk voltage target value from a predetermined reference value at a predetermined timing when the control mode is switched, thereby increasing or decreasing the bulk voltage under the bulk voltage control by the charging control unit 85 by a predetermined amount from the predetermined reference voltage.

[0132] More specifically, when the control mode is switched (i.e., when the control mode is switched between the power supply mode and the power supply during charging mode, and when the control mode is switched between the charging mode and the power supply during charging mode), during the period from when the charging / power supply request is acquired by the charging / power supply request acquisition unit 81 to when the operation target of the bulk voltage control by the charging power supply control unit 85 is switched from the pre-switching operation target to the post-switching operation target and while the charging power supply control unit 85 is performing bulk voltage control using the pre-switching operation target, the bulk voltage target value is increased or decreased by a predetermined offset value from the reference value at the time when the charging request is acquired.

[0133] When the bulk voltage target value is increased or decreased at such timing, the charging control unit 85 increases or decreases the bulk voltage by the amount corresponding to the offset value from the reference voltage at the time when the charging request is acquired, by the bulk voltage control using the pre-switching operation target during the period from when the charging request is acquired until the operation target of the bulk voltage control is switched from the pre-switching operation target to the post-switching operation target. This makes it possible to suppress the occurrence of UV or OV when the control mode is switched.

[0134] That is, when there is a concern about UV occurring when the control mode is switched, the bulk voltage target value setting unit 86 increases the bulk voltage target value from the above-mentioned reference value by the offset value so that the bulk voltage at the time of switching the control mode is away from the lower threshold. Also, when there is a concern about OV occurring when the control mode is switched, the bulk voltage target value setting unit 86 decreases the bulk voltage target value from the above-mentioned reference value by the offset value so that the bulk voltage at the time of switching the control mode is away from the upper threshold.

[0135] As described above, whether UV or OV is a concern varies depending on the control mode switching scene, and the fluctuation range of the bulk voltage when the control mode is switched may also vary depending on the control mode switching scene. Therefore, when a power supply request is acquired, it is preferable that the bulk voltage target value setting unit 86 determines a specific fluctuation pattern of the bulk voltage target value when the control mode is switched by referring to a table such as that shown in FIG.

[0136] Fig. 7 is a diagram showing an example of a fluctuation pattern determination table for determining a fluctuation pattern of a bulk voltage target value when switching control modes. As shown in Fig. 7, the fluctuation pattern determination table associates a pre-switching control mode (or a pre-switching operation target), a post-switching control mode (or a post-switching operation target) determined by the flowcharts of Figs. 5A and 5B based on the contents of a power supply request, and a fluctuation pattern of a bulk voltage target value.

[0137] According to the example of the fluctuation pattern determination table in Fig. 7, when transitioning from the power supply mode to the charging power supply mode, i.e., when the operation target of the bulk voltage control is switched from the DC-DC converter 3 to the half PFC circuit, there is a concern that UV may occur, so the bulk voltage target value setting unit 86 increases the bulk voltage target value by value A. When transitioning from the charging power supply mode to the power supply mode, i.e., when the operation target of the bulk voltage control is switched from the half PFC circuit to the DC-DC converter 3, there is a concern that UV may occur, so the bulk voltage target value setting unit 86 increases the bulk voltage target value by value B. When transitioning from the charging mode to the charging power supply mode, i.e., when the operation target of the bulk voltage control is switched from the full PFC circuit to the half PFC circuit, there is a concern that OV may occur, so the bulk voltage target value setting unit 86 decreases the bulk voltage target value by value C. When transitioning from the charging power supply mode to the charging mode, that is, when switching the operation target of the bulk voltage control from the half PFC circuit to the full PFC circuit, the bulk voltage target value setting unit 86 lowers the bulk voltage target value by value D.

[0138] The variation pattern determination table shown in Fig. 7 is merely an example, and the present invention is not limited thereto. In other words, whether to increase or decrease the bulk voltage target value for each control mode transition pattern is preferably determined in advance by designing and testing that assumes variations. Similarly, the detailed value of the offset value is preferably determined in advance by designing and testing that assumes variations.

[0139] Next, specific control examples in which the occurrence of UV and the occurrence of OV are suppressed by varying the bulk voltage target value will be described with reference to FIGS. 8 and 9. FIG.

[0140] Fig. 8 is a time chart showing a control example in the case where UV generation is a concern when shifting from the power supply mode to the charging-in-progress power supply mode. Fig. 8 shows a case where a charging start request is acquired at time t41 while power is being supplied to the external AC load EL in the power supply mode. Fig. 8 also shows a case where, in response to the charging start request being acquired at time t41, the charging control unit 85 ends the bulk voltage control with the DC-DC converter 3 as the operation target at time t43, then starts the bulk voltage control with the half PFC circuit as the operation target at time t45, and then completes the shift to the charging-in-progress power supply mode at time t46 in response to the charging current being stabilized.

[0141] First, a case will be described in which the bulk voltage target value is kept fixed without being changed from when a charging start request is acquired at time t41 until when bulk voltage control using the DC-DC converter 3 as the pre-switching operation target is ended at time t43. In this case, if the bulk voltage control is stopped at time t43 while continuing to supply a power supply current to the external AC load EL, the bulk voltage starts to decrease as shown in the second row from the bottom in Fig. 8. For this reason, if the period during which the bulk voltage control is stopped is prolonged, the bulk voltage will fall below the lower limit threshold at time t44, and UV will occur before the bulk voltage control is resumed, which may cause the system to stop.

[0142] In response to this, the bulk voltage target value setting unit 86 raises the bulk voltage target value by a predetermined offset value with the value at time t41 when the charging start request is acquired as a reference value during the period from when the charging start request is acquired until the operation target is switched from the DC-DC converter 3 to the half PFC circuit and while the charging control unit 85 is performing bulk voltage control using the DC-DC converter 3 (between time t41 and t43 in the example of FIG. 8), in order to suppress the generation of UV as described above. In response to this, the charging control unit 85 performs bulk voltage control using the DC-DC converter 3, and raises the bulk voltage by an amount corresponding to the offset value from the reference voltage with the bulk voltage at time t41 as a reference voltage during the period from time t42 to time t43. Therefore, while continuing to supply a power supply current to the external AC load EL, the bulk voltage does not fall below the lower limit threshold during the period from when the bulk voltage control is stopped at time t43 until when the bulk voltage control is started at time t45. That is, the generation of UV can be suppressed.

[0143] Incidentally, the drop in the bulk voltage while the bulk voltage control is stopped increases as the power supply current to the external AC load EL increases. For this reason, when switching the control mode between the power supply mode and the charging power supply mode, i.e., when switching the control mode while continuing power supply to the external AC load EL, it is preferable that the bulk voltage target value setting unit 86 changes the offset value according to the magnitude of the power supply current acquired by the power supply current acquisition unit 87. More specifically, since the drop in the bulk voltage increases as the power supply current increases, it is preferable that the bulk voltage target value setting unit 86 changes the offset value to a larger value as the power supply current increases.

[0144] Fig. 9 is a time chart showing a control example in the case where there is a concern of an OV occurring when shifting from the power supply mode to the charging-in-progress power supply mode. Fig. 9 shows a case where a charging start request is acquired at time t51 while power is being supplied to the external AC load EL in the power supply mode. Fig. 9 also shows a case where, in response to the charging start request being acquired at time t51, the charging control unit 85 ends the bulk voltage control with the DC-DC converter 3 as the operation target at time t53, then starts the bulk voltage control with the half PFC circuit as the operation target at time t54, and then completes the shift to the charging-in-progress power supply mode at time t56 in response to the charging current being stabilized.

[0145] First, a case will be described in which the bulk voltage target value is kept fixed without being changed from when a charging start request is acquired at time t51 until when the bulk voltage control using the DC-DC converter 3 as the pre-switching operation target is terminated at time t53. In this case, if the bulk voltage control using the DC-DC converter 3 is terminated at time t53 and then the bulk voltage control using the half PFC circuit as the operation target is resumed at time t54, the bulk voltage may overshoot the bulk voltage target value immediately thereafter, as shown in the second row from the bottom in Fig. 9. Therefore, at time t55, the bulk voltage exceeds the upper limit threshold, and OV occurs before the bulk voltage control is resumed, which may cause the system to stop.

[0146] In response to this, the bulk voltage target value setting unit 86 reduces the bulk voltage target value by a predetermined offset value with the value at time t51 when the charging start request is acquired as a reference value during the period from when the charging start request is acquired until the operation target is switched from the DC-DC converter 3 to the half PFC circuit and while the charging control unit 85 is performing bulk voltage control using the DC-DC converter 3 (between time t51 and t53 in the example of FIG. 9 ). In response to this, the charging control unit 85 performs bulk voltage control using the DC-DC converter 3, and reduces the bulk voltage by a width according to the offset value from the reference voltage with the bulk voltage at time t51 as the reference voltage during the period from time t52 to time t53. Therefore, the bulk voltage at the time when the bulk voltage control using the half PFC circuit as the operation target is started at time t54 can be made farther from the upper limit threshold than when the bulk voltage target value is fixed. Therefore, even if the bulk voltage overshoots the bulk voltage target value immediately after the bulk voltage control is resumed at time t54, the bulk voltage will not exceed the upper limit threshold. In other words, the occurrence of OV can be suppressed.

[0147] In addition, the specific procedures for suppressing the occurrence of UV and OV when transitioning from the power supply mode during charging to the power supply mode, when transitioning from the charging mode to the power supply mode during charging, and when transitioning from the power supply mode during charging to the charging mode are almost the same as the procedures described with reference to Figures 8 and 9, so detailed description will be omitted.

[0148] The power supply system 1 according to this embodiment provides the following advantages. (1) The charging / power supply request acquisition unit 81 acquires a charging / power supply request for charging the high-voltage battery B or supplying power to the external AC load EL, and the charging / power supply control unit 85 performs bulk voltage control by operating the DC-DC converter 3 in the power supply mode, and performs bulk voltage control by operating the power converter 6 in the charging mode and the power supply mode during charging. When the charging / power supply control unit 85 switches the control mode between the power supply mode and the power supply mode during charging in response to the acquisition of the charging request, the charging / power supply control unit 85 increases or decreases the bulk voltage by a predetermined amount from the time when the charging request is acquired until the operation target of the bulk voltage control is switched between the DC-DC converter 3 and the power converter 6. According to the power supply system 1, the charging / power supply control unit 85 increases the bulk voltage by a predetermined amount from the time when the charging request is acquired, thereby suppressing the generation of UV. The charging / power supply control unit 85 decreases the bulk voltage by a predetermined amount from the time when the charging request is acquired, thereby suppressing the generation of OV. Therefore, according to the power supply system 1, by suppressing the occurrence of UV and OV when switching the control mode, it is possible to suppress the forced stopping of ongoing charging and supplying, which can ultimately contribute to energy efficiency.

[0149] (2) In the charging mode, the switch control unit 84 sets the switch circuit 65 to a first connection state and connects the converter circuits 71, 72 of the power converter 6 to the inlet 4, and in the power supply mode and the power supply mode during charging, sets the switch circuit 65 to a second connection state and connects the first converter circuit 71 to the inlet 4 and connects the second converter circuit 72 to the outlet 5. In the charging mode, the charge and supply control unit 85 performs bulk voltage control by operating a full PFC circuit constituted by the converter circuits 71, 72 as a PFC converter, in the power supply mode, performs bulk voltage control by operating the DC-DC converter 3, and in the power supply mode, performs bulk voltage control by operating a half PFC circuit constituted by the first converter circuit 71 as a PFC converter. Furthermore, when switching the control mode between the charging mode and the power supply during charging mode, the charging control unit 85 can suppress the occurrence of UV or OV when the control mode is switched by increasing or decreasing the bulk voltage by a predetermined amount from the time when the charging request is acquired until the operation target of the bulk voltage control is switched between the full PFC circuit and the half PFC circuit after the charging request is acquired.

[0150] (3) In the charging mode, the charging / supplying control unit 85 performs bulk voltage control by operating the full PFC circuit as a PFC converter, and simultaneously performs charging current control by operating the DC-DC converter 3, and in the power supply mode, performs bulk voltage control by operating the DC-DC converter 3, and simultaneously performs power supply current control by operating the second converter circuit 72 as an inverter. In the power supply mode during charging, the charging / supplying control unit 85 performs bulk voltage control by operating the half PFC circuit as a PFC converter, performs power supply current control by operating the second converter circuit 72 as an inverter, and simultaneously performs charging current control by operating the DC-DC converter 3. According to the power supply system 1, charging, power supply, and power supply during charging can be performed using a common power converter 6, which can reduce costs and contribute to energy efficiency, compared to the case where charging and power supply are performed using separate units.

[0151] (4) When the control mode is shifted from the charging mode to the power supply during charging mode, the charging power supply control unit 85 causes only the first converter circuit 71 of the full PFC circuit to continue to operate as a PFC converter while causing the second converter circuit 72, which had been operating as a PFC converter until then, to start operating as an inverter. As a result, when the control mode is shifted from the charging mode to the power supply during charging mode, it is possible to continue charging the high-voltage battery B and start power supply to the external AC load EL while suppressing the occurrence of UV, OV, and the like as described above.

[0152] (5) When the control mode is shifted from the power supply during charging mode to the charging mode, the charging power supply control unit 85 causes the second converter circuit 72, which had been operating as an inverter until then, to start operating as a PFC converter while continuing to operate the first converter circuit 71 as a PFC converter. As a result, when the control mode is shifted from the power supply during charging mode to the charging mode, it is possible to continue charging the high-voltage battery B and stop power supply to the external AC load EL while suppressing the occurrence of UV and OV as described above.

[0153] (6) When the control mode is shifted from the power supply mode to the power supply mode during charging, the charging power supply control unit 85 starts operating the first converter circuit 71 as a PFC converter while continuing to operate the second converter circuit 72 as an inverter. As a result, when the control mode is shifted from the power supply mode to the power supply mode during charging, it is possible to continue supplying power to the external AC load EL and start charging the high-voltage battery B while suppressing the occurrence of UV and OV as described above.

[0154] (7) When the control mode is shifted from the charging power supply mode to the power supply mode, the charging power supply control unit 85 stops the operation of the first converter circuit 71 that had been operating as a PFC converter while continuing to operate the second converter circuit 72 as an inverter. As a result, when the control mode is shifted from the charging power supply mode to the power supply mode, it is possible to continue the power supply to the external AC load EL and stop charging of the high-voltage battery B while suppressing the occurrence of UV and OV as described above.

[0155] (8) The charging control unit 85 operates the pre-switching operation target to increase the bulk voltage by a predetermined width from the time when the charging request was acquired until the operation target of the bulk voltage control is switched from the pre-switching operation target to the post-switching operation target after the charging request is acquired. This allows the bulk voltage at the time when the bulk voltage control using the pre-switching operation target is stopped to be away from the lower limit threshold when the control mode is switched, so that the occurrence of UV can be suppressed from the time when the voltage control using the pre-switching operation target is stopped to the time when the bulk voltage control using the post-switching operation target is started. In addition, the charging control unit 85 operates the pre-switching operation target to decrease the bulk voltage by a predetermined width from the time when the charging request was acquired until the operation target of the bulk voltage control is switched from the pre-switching operation target to the post-switching operation target after the charging request is acquired. This allows the bulk voltage at the time when the bulk voltage control using the post-switching operation target is started to be away from the upper limit threshold when the control mode is switched, so that the occurrence of OV can be suppressed immediately after the bulk voltage control using the post-switching operation target is started.

[0156] (9) In the bulk voltage control, the charging control unit 85 operates the operation target so that the bulk voltage becomes the bulk voltage target value set by the bulk voltage target value setting unit 86, and the bulk voltage target value setting unit 86 increases or decreases the bulk voltage target value by a predetermined offset value from the time when the charging request is acquired until the operation target is switched from the pre-switching operation target to the post-switching operation target after the switching from the time when the charging request is acquired. This makes it possible to suppress the occurrence of UV or OV when the control mode is switched.

[0157] (10) When the control mode is switched between the power supply mode and the power charging mode, that is, when power supply to the external AC load EL is continued before and after the control mode is switched, the amount of change in the bulk voltage during the temporary suspension of the bulk voltage control varies depending on the magnitude of the power supply current. Therefore, when the control mode is switched between the power supply mode and the power supply during charging mode, the bulk voltage target value setting unit 86 changes the offset value according to the power supply current to the external AC load EL. This allows the offset value to be set to an appropriate value in anticipation of the change in the bulk voltage during the temporary suspension of the bulk voltage control, so that the occurrence of UV and OV when the control mode is switched between the power supply mode and the power charging mode can be more reliably suppressed.

[0158] Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment. The detailed configuration may be appropriately changed within the scope of the spirit of the present invention.

[0159] For example, in the above embodiment, the power converter 6 is provided with a total of four switching legs 61 to 64, the first converter circuit 71 is configured by two switching legs 61 and 64, and the second converter circuit 72 is configured by two switching legs 62 and 63, but the present invention is not limited to this. The first converter circuit 71 may be configured by two or more switching legs, and the second converter circuit 72 may be configured by one or more switching legs. Note that when the number of switching legs constituting the second converter circuit 72 is one, it is preferable that the other leg is a rectifier circuit.

[0160] In the above embodiment, the case where a single-phase two-wire external AC power supply EP is mainly connected to the inlet 4 has been described, but the present invention is not limited thereto. As described with reference to FIG. 2, a three-phase four-wire external AC power supply EP' may be connected to the inlet 4. In this case, when the three voltage lines EL1, EL2, EL3 and the neutral line EN of the external AC power supply EP' are connected to the power lines L1, L2, L3, N1, respectively, in the charging mode, three-phase AC power can be supplied to the power converter 6 to charge the high-voltage battery B, but in the power supply mode during charging, it is not possible to supply the three-phase AC power to the power converter 6 and supply power to the external AC load EL at the same time. However, in the power supply mode during charging, it is possible to supply single-phase AC power from the external AC power supply EP' to the power converter 6 and supply power to the external AC load EL at the same time by using only the two power lines L1 and N1. [Explanation of symbols]

[0161] V…Vehicle 1. Power supply system B…High voltage battery (energy storage device) 21, 22…Power lines 23...Bulk capacitor (capacitor) 3...DC-DC converter (voltage converter) 4. Inlet L1,L2,L3,N1…power line EP,EP´…External AC power supply (external power supply) EL1,EL2,EL3...Voltage line EN: Neutral conductor 5. Outlet L4, N2…Power lines EL…External AC load (external load) 6...Power converter 61…First switching leg 62…Second switching leg 63…Third switching leg 64…4th switching leg 65...Switch circuit 71...First converter circuit 72…Second converter circuit 8...Control device 81...Charging / power supply request acquisition unit (request acquisition unit) 82...Operation status information acquisition unit 83...Control mode determination unit 84...Switch control section 85...Charging and power supply control unit 86…Bulk voltage target value setting unit 87…Power supply current acquisition section 88...Abnormality determination section

Claims

1. A power storage device; A voltage converter connected to the power storage device; An inlet to which an external power supply can be connected; An outlet to which an external load can be connected; a power converter connected to the inlet and the outlet; a bulk capacitor provided on a power line connecting the voltage converter and the power converter; a control device that operates the voltage converter and the power converter under any one of a charging mode in which the power storage device is charged by the external power source, a power supply mode in which power is supplied to the external load, and a power-during-charging supply mode in which power is supplied to the external load while charging the power storage device, The control device includes: a charge / power supply request acquisition unit that acquires a charge / power supply request for charging the power storage device or supplying power to the external load; a charge / supply control unit that performs voltage control of a bulk voltage, which is a voltage of the bulk capacitor, by operating the voltage converter in the power supply mode, and performs the voltage control by operating the power converter in the charging mode and the power supply mode during charging, the charging control unit, when switching the control mode between the power supply mode and the power supply during charging mode in response to the acquisition of the charging request, increases or decreases the bulk voltage by a predetermined amount from the time when the charging request is acquired until the operation target of the voltage control is switched between the voltage converter and the power converter.

2. The power converter includes: a first converter circuit including two or more switching legs connected to the power line; a second converter circuit including one or more switching legs connected to the power line in parallel with the first converter circuit; a switch circuit switchable between a first connection state in which both the first and second converter circuits are connected to the inlet and a second connection state in which the first and second converter circuits are connected to the inlet and the outlet, respectively; the control device further includes a switch control unit that sets the switch circuit to the first connection state in the charging mode and sets the switch circuit to the second connection state in the power supply mode and the power supply during charging mode, The charging and power supply control unit is In the charging mode, a full PFC circuit constituted by the first and second converter circuits is operated as a PFC converter having the inlet as an input side to perform the voltage control; In the power supply mode, the voltage control is performed by operating the voltage converter; In the charging power supply mode, the voltage control is performed by operating a half PFC circuit constituted by the first converter circuit as the PFC converter; 2. The power supply system according to claim 1, wherein, when the control mode is switched between the charging mode and the power supply during charging mode in response to the acquisition of the charging request, the charging control unit increases or decreases the bulk voltage by a predetermined amount from the time when the charging request is acquired until the operation target is switched between the full PFC circuit and the half PFC circuit.

3. The charging and power supply control unit is In the charging mode, the voltage control is performed by operating the full PFC circuit as the PFC converter, and at the same time, a charging current control for the power storage device is performed by operating the voltage converter; In the power supply mode, the voltage control is performed by operating the voltage converter, and at the same time, the power supply current control for the external load is performed by operating the second converter circuit as an inverter having the bulk capacitor as an input side; 3. The power supply system according to claim 2, wherein, in the charging power supply mode, the voltage control is performed by operating the half PFC circuit as the PFC converter, the power supply current control is performed by operating the second converter circuit as the inverter, and the charging current control is performed by operating the voltage converter at the same time.

4. 4. The power supply system according to claim 3, wherein, when the control mode is shifted from the charging mode to the power supply mode during charging, the charge and supply control unit starts to operate the second converter circuit as the inverter while continuing to operate the first converter circuit as the PFC converter.

5. 4. The power supply system according to claim 3, wherein, when the control mode is shifted from the power supply mode during charging to the charging mode, the charge and supply control unit starts to operate the second converter circuit as the PFC converter while continuing to operate the first converter circuit as the PFC converter.

6. 4. The power supply system according to claim 3, wherein, when the control mode is shifted from the power supply mode to the during-charging power supply mode, the charging and power supply control unit starts to operate the first converter circuit as the PFC converter while continuing to operate the second converter circuit as the inverter.

7. 4. The power supply system according to claim 3, wherein when the control mode is transitioned from the charging-time power supply mode to the power supply mode, the charging and power supply control unit stops operation of the first converter circuit while continuing to operate the second converter circuit as the inverter.

8. 8. The power supply system according to claim 1, wherein, when the operation target before and after switching the control mode are defined as a pre-switching operation target and a post-switching operation target, respectively, the charging control unit operates the pre-switching operation target during a period from when the charging request is acquired to when the operation target is switched from the pre-switching operation target to the post-switching operation target, thereby increasing or decreasing the bulk voltage by a predetermined amount from the time when the charging request is acquired.

9. The control device further includes a target value setting unit that sets a bulk voltage target value in the voltage control, the charging / supply control unit operates the operation target in the voltage control so that the bulk voltage becomes the bulk voltage target value; The power supply system according to claim 8, characterized in that the target value setting unit increases or decreases the bulk voltage target value by a predetermined offset value from the point at which the charging request is acquired until the operation target is switched from the pre-switching operation target to the post-switching operation target after the switching after the charging request is acquired.

10. The control device further includes a power supply current acquisition unit that acquires a power supply current to the external load, 10. The power supply system according to claim 9, wherein the target value setting unit changes the offset value in accordance with the power supply current when the control mode is switched between the power supply mode and the power supply during charging mode.

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