JP2021191203A - Power system and charger - Google Patents

Abstract

To provide a power system and a charger, capable of suitably charging a target power storage device using at least one of a system power supply and a power supply power storage device.SOLUTION: A power system 10 charges a vehicle power storage device 21 as a target power storage device using at least one of a system power supply 11 and a power supply power storage device 12. The power system 10 comprises: a charger 30 having, as a charging mode for charging the vehicle power storage device 21, a first system mode using the system power supply 11, a second system mode using both of the system power supply 11 and the power supply power storage device 12, and a power supply mode using the power supply power storage device 12; and a control ECU 120 for controlling the charging mode. The control ECU 120 controls the charging mode on the basis of a target SOC Xa and a power supply SOC Xb and switches the charging mode in response to variation in the target SOC Xa during charging of the vehicle power storage device 21.SELECTED DRAWING: Figure 1

Description

The present invention relates to a power system and a charging device.

For example, Patent Document 1 describes a power system in which a storage battery as a power storage device is connected to a power system as a system power source. In the power system, the power output from the power storage device is converted into system power, output to the power system, and supplied to the load as system power.

JP-A-2019-68618

Here, in a power system having a power storage device, it is conceivable to use at least one of the system power supply and the power storage device as a power source to charge the target power storage device. In this case, it may be desired to switch the power source used for charging the target power storage device depending on the situation.

In particular, when the target power storage device is charged, the SOC of the target power storage device changes as the target power storage device is charged. Then, the electric power suitable for charging the target power storage device changes, and as a result, it may not be possible to supply the electric power suitable for charging, or unintended electric power may be supplied.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a power system and a charging device capable of suitably charging a target power storage device using at least one of a system power supply and a power storage device. It is to be.

A power system that achieves the above object charges a target power storage device using at least one of a system power supply and a power storage device, and uses the system power supply as a charging mode for charging the target power storage device. A charging device having one system mode, a second system mode using both the system power supply and the power storage device, and a power supply mode using the power power storage device, and a target that is the SOC of the target power storage device. A control unit that controls the charging mode based on the SOC and the power supply SOC that is the SOC of the power storage device is provided, and the control unit changes the target SOC during charging of the target power storage device. The charging mode is switched according to the above.

According to this configuration, there are a first system mode, a second system mode, and a power supply mode as charging modes for charging the target power storage device. Therefore, the target power storage device is used by using either the system power supply or the power storage device. It can be charged or the target power storage device can be charged using both the system power supply and the power storage device. Further, by controlling the charging mode based on the target SOC and the power supply SOC, it is possible to select an appropriate charging mode according to the situation.

In particular, the target SOC changes during charging of the target power storage device. When the target SOC changes, the power suitable for charging the target power storage device also changes. In this regard, according to this configuration, since the charging mode is switched according to the change of the target SOC during charging of the target power storage device, the charging mode is set to the change of the power suitable for charging the target power storage device due to the change of the target SOC. It can be made to follow. Therefore, the target power storage device can be suitably charged.

With respect to the power system, the control unit sets the charging mode to the second system mode when the target SOC is lower than the predetermined system target threshold value and the power supply SOC is equal to or higher than the predetermined power supply threshold value. When the target SOC is equal to or higher than the system target threshold value, the charging mode may be set to the first system mode.

According to this configuration, the charging mode is set when the target SOC is lower than the system target threshold value and the power supply SOC is equal to or higher than the power supply threshold value, in response to the fact that the power suitable for charging tends to increase as the target SOC becomes lower. It is set to the second system mode. As a result, the target power storage device can be charged using both the system power supply and the power storage device, so that a large amount of electric power can be supported.

Further, as a condition for setting the charging mode to the second system mode, it is included that the power supply SOC is equal to or higher than the power supply threshold value. As a result, inconveniences caused by the discharge of the power storage device even though the power storage amount is small, for example, sufficient power cannot be supplied or the power power storage device deteriorates. It is possible to suppress the operation.

On the other hand, when the target SOC is higher than the target SOC, the power suitable for charging tends to be smaller, and when the target SOC is equal to or higher than the system target threshold value, the charging mode is set to the first system mode. As a result, it is possible to supply electric power suitable for charging without using a power storage device.

For the power system, the control unit may set the charging mode to the first system mode when the target SOC is lower than the system target threshold value and the power supply SOC is lower than the power supply threshold value.

According to this configuration, even if the target SOC is lower than the system target threshold value, if the power supply SOC is lower than the power supply threshold value, the target power storage is performed using only the system power supply without using the power storage device. The device is charged. As a result, it is possible to charge the target power storage device while suppressing the inconvenience caused by the discharge of the power power storage device even though the power storage amount of the power power storage device is small.

With respect to the power system, the power suitable for charging the target power storage device is the first power when the target SOC is equal to or less than a predetermined first target value, and the target SOC is the first target value. When it is higher than the second target value, it is the second power, which decreases from the first target value toward the second target value, and is the maximum power that can be output by the system power supply. The system maximum power is higher than the first power and lower than the second power, and the system target threshold is the target SOC in which the power suitable for charging the target power storage device is the system maximum power. good.

According to this configuration, the charging mode becomes the second system mode until the power suitable for charging the target power storage device becomes the system maximum power, and when the power suitable for charging the target power storage device becomes smaller than the system maximum power, The charging mode switches from the second system mode to the first system mode. Thereby, the target power storage device can be suitably charged under the condition that the maximum system power is set between the first power and the second power.

Regarding the power system, when the charging mode is the second system mode, the control unit maintains the system power output from the system power supply at the system maximum power in response to a change in the target SOC. While doing so, it is preferable to variably control the power supply power output from the power storage device.

According to such a configuration, since the system power is maintained at the system maximum power, the power supply power can be reduced as much as possible. As a result, charging / discharging of the power storage device can be suppressed, and deterioration of the power storage device can be suppressed through this.

With respect to the power system, the control unit sets the charging mode to the second charging mode when the target SOC is lower than the predetermined power target threshold in a situation where the power SOC is equal to or higher than the predetermined power threshold. On the other hand, when the target SOC is equal to or higher than the power target threshold in a situation where the power supply SOC is equal to or higher than the power supply threshold value, the charging mode may be set to the power supply mode.

According to this configuration, the charging mode is set when the power supply SOC is equal to or higher than the power supply threshold value and the target SOC is lower than the power supply target threshold value, in response to the fact that the power suitable for charging tends to increase when the target SOC becomes low. It is set to the second system mode. As a result, the target power storage device can be charged using both the system power supply and the power storage device, so that a large amount of electric power can be supported.

On the other hand, in response to the fact that the power suitable for charging tends to decrease as the target SOC increases, the charging mode is set to the power mode when the power supply SOC is equal to or higher than the power supply threshold value and the target SOC is equal to or higher than the power supply target threshold value. Will be done. As a result, it is possible to supply power suitable for charging using only the power storage device.

Further, as a condition for setting the charging mode to the second system mode or the power supply mode, it is included that the power supply SOC is equal to or higher than the power supply threshold value. As a result, inconveniences caused by the discharge of the power storage device even though the power storage amount is small, for example, sufficient power cannot be supplied or the power power storage device deteriorates. It is possible to suppress the operation.

With respect to the power system, the power suitable for charging the target power storage device is the first power when the target SOC is equal to or less than a predetermined first target value, and the target SOC is the first target value. When it is higher than the second target value, it is the second power, which decreases from the first target value toward the second target value, and is the maximum power that can be output by the power storage device. The maximum power source power is higher than the first power source and lower than the second power source, and the power source target threshold is the target SOC in which the power suitable for charging the target power storage device is the power source maximum power. It would be nice to have it.

According to this configuration, the charging mode is the second system mode until the power suitable for charging the target power storage device becomes the maximum power supply, and when the power suitable for charging the target power storage device becomes smaller than the maximum power supply power. The charging mode switches from the second system mode to the power mode. As a result, in a situation where the maximum power source power is set between the first power source and the second power source, it is possible to suitably charge the target power storage device while preferentially using the power storage device. ..

For the power system, the charging device is a first transformer comprising a first primary winding and a first secondary winding having a first intermediate tap to which the power storage device is connected. And a second primary winding connected in series with the first primary winding, and a second secondary winding having a second intermediate tap to which the target power storage device is connected. A power conversion circuit connected to the system power supply and connected to a series connection of the first primary winding and the first secondary winding. A primary side circuit having a primary side switching element and a power conversion circuit connected to the power storage device, the first two provided between the first intermediate tap and the power storage device. A first secondary circuit having a secondary coil and a first secondary switching element connected to the first secondary winding, the first secondary circuit, and the target power storage. A power conversion circuit provided between the device and a second secondary coil provided between the second intermediate tap and the target power storage device, and connected to the second secondary winding. A second secondary circuit having a second secondary switching element, and an intermediate capacitor provided between the first secondary circuit and the second secondary circuit. The control unit may control the charging mode by controlling the primary side switching element, the first secondary side switching element, and the second secondary side switching element.

According to such a configuration, by controlling the primary side switching element, the first secondary side switching element, and the second secondary side switching element, it is possible to charge the target power storage device while controlling the charging mode. can.

Regarding the power system, the charging device is an AC / DC conversion circuit that converts system power output from the system power supply into DC power, and a power conversion circuit connected to the power storage device. A first conversion circuit having a conversion switching element, a power conversion circuit connected to both the AC / DC conversion circuit and the first conversion circuit, the second conversion circuit having a second conversion switching element, and the above. An intermediate capacitor provided between the AC / DC conversion circuit and the second conversion circuit and connected to the first conversion circuit is provided, and the DC power converted by the second conversion circuit is used as the target power storage device. The control unit may control the charging mode by controlling the AC / DC conversion circuit, the first conversion switching element, and the second conversion switching element.

According to this configuration, the target power storage device is charged while controlling the charging mode by controlling the AC / DC conversion circuit, the first conversion switching element of the first conversion circuit, and the second conversion switching element of the second conversion circuit. can.

The charging device that achieves the above object is used to charge the target power storage device using at least one of the system power supply and the power storage device, and the system power supply is used as the charging mode for charging the target power storage device. It has one system mode, a second system mode using both the system power supply and the power storage device, and a power supply mode using the power power storage device, and is the SOC of the target power storage device. A control unit that controls the charging mode based on the target SOC and the power supply SOC that is the SOC of the power storage device is provided, and the control unit changes the target SOC during charging of the target power storage device. The charging mode is switched accordingly.

According to this configuration, there are a first system mode, a second system mode, and a power supply mode as charging modes for charging the target power storage device. Therefore, the target power storage device is used by using either the system power supply or the power storage device. It can be charged or the target power storage device can be charged using both the system power supply and the power storage device. Further, by controlling the charging mode based on the target SOC and the power supply SOC, it is possible to select an appropriate charging mode according to the situation.

In particular, the target SOC changes during charging of the target power storage device. When the target SOC changes, the power suitable for charging the target power storage device also changes. In this regard, according to this configuration, the charging mode is switched according to the change of the target SOC while the target power storage device is being charged. Therefore, when the power suitable for charging the target power storage device changes with the change of the target SOC. Even if there is, the charging mode can be made to follow the electric power suitable for the charging. Therefore, the target power storage device can be suitably charged.

According to the present invention, the target power storage device can be suitably charged by using at least one of the system power supply and the power storage device.

The circuit diagram which shows the outline of the charging device and the electric power system of 1st Embodiment. The flowchart which shows the charge control process of 1st Embodiment. The graph which shows the relationship between the target SOC and the electric power suitable for charging. The graph which shows the time change of the target power, the system target power, and the power source target power during charging of the power storage device for a vehicle. The flowchart which shows the charge control process of 2nd Embodiment. The circuit diagram which shows the outline of the charging device of 3rd Embodiment.

(First Embodiment)
Hereinafter, the first embodiment of the electric power system and the charging device will be described. In this embodiment, the charging device is installed in a factory, a commercial facility, or the like. That is, the power system of this embodiment is not for home use but for commercial or industrial use.

As shown in FIGS. 1 and 2, the power system 10 of the present embodiment charges a vehicle power storage device 21 as a target power storage device provided in the vehicle 20, and is for a power source different from the system power supply 11. It includes a power storage device 12 and a charging device 30.

The grid power supply 11 outputs, for example, a three-phase grid power Pa. The maximum grid power Pamax, which is the maximum value of the grid power Pa that can be supplied by the grid power supply 11, varies depending on the contents of the contract with the power company, the power usage status of other power systems, and the like.

The power storage device 12 is, for example, a secondary battery or an electric double layer capacitor. The power supply voltage Vp, which is the voltage of the power storage device 12, varies depending on the SOC (charging state) of the power storage device 12. As an example, the power supply voltage Vp increases as the SOC of the power storage device 12 increases. Specifically, the power supply voltage Vp varies over the range from the minimum power supply voltage Vpmin to the maximum power supply voltage Vpmax.

The vehicle 20 includes, in addition to the vehicle power storage device 21 as the target power storage device, a vehicle ECU 22 that controls the vehicle power storage device 21.
The vehicle power storage device 21 is, for example, a secondary battery or an electric double layer capacitor. In the present embodiment, the DC power of the charging voltage Vr is input to the vehicle power storage device 21 to charge the vehicle power storage device 21. Therefore, the charging voltage Vr is the voltage of the vehicle power storage device 21, and can be said to be the required voltage required for the vehicle power storage device 21 to charge. Further, the charging voltage Vr can be said to be the required voltage of the load.

The charging voltage Vr, which is the voltage of the vehicle power storage device 21, varies depending on the type of the vehicle power storage device 21 and the SOC (charging state). For example, the charging voltage Vr differs depending on whether the vehicle power storage device 21 is a lithium ion battery or a lead storage battery. Further, in general, the charging voltage Vr increases as the SOC of the vehicle power storage device 21 increases.

Here, the minimum value of the charging voltage Vr assumed in the power system 10 is referred to as the minimum charging voltage Vrmin, and the maximum value of the charging voltage Vr is referred to as the maximum charging voltage Vrmax. The charging voltage Vr varies over the range from the minimum charging voltage Vrmin to the maximum charging voltage Vrmax.

In the present embodiment, the minimum power supply voltage Vpmin is lower than the minimum charge voltage Vrmin, and the maximum power supply voltage Vpmax is higher than the minimum charge voltage Vrmin. Specifically, Vpmin <Vrmin <Vpmax <Vrmax. Therefore, depending on the SOCs of both power storage devices 12 and 21, the power supply voltage Vp may be lower than the charging voltage Vr, or the power supply voltage Vp may be higher than the charging voltage Vr. The specific configuration of the power storage device 12 and the vehicle power storage device 21 is arbitrary.

The maximum charging voltage Vrmax is set higher than the maximum power supply voltage Vpmax. This makes it possible to expand the range of the vehicle power storage device 21 applicable to the power system 10. Therefore, it is possible to improve versatility.

The vehicle ECU 22 controls the charging of the vehicle power storage device 21. The vehicle ECU 22 is configured to be electrically connectable to the charging device 30. When the vehicle ECU 22 is electrically connected to the charging device 30, the vehicle ECU 22 communicates with the charging device 30 to transmit necessary information such as the SOC of the vehicle power storage device 21.

The charging device 30 has a connector 40 as a load connecting portion used for electrically connecting to the vehicle 20. By connecting the connector 40 to the vehicle 20, the charging device 30, the vehicle power storage device 21, and the vehicle ECU 22 are electrically connected. The connector 40 can be said to be a connection portion for connecting the load and the charging device 30.

As shown in FIG. 2, the connector 40 includes a positive electrode load input terminal 41 connected to the positive electrode terminal of the vehicle power storage device 21, a negative electrode load input terminal 42 connected to the negative electrode terminal of the vehicle power storage device 21, and a vehicle. It has a control terminal 43 connected to the ECU 22.

The charging device 30 has a negative electrode wiring 44 that connects the negative electrode storage input terminal 35 and the negative electrode load input terminal 42. As a result, the negative electrodes of the power storage device 12 and the vehicle power storage device 21 are electrically connected to each other.

In this embodiment, the number of connectors 40 is one for convenience of explanation. However, the present invention is not limited to this, and the charging device 30 may have a plurality of connectors 40 connected in parallel to each other and may be configured to be connectable at the same time as the plurality of vehicles 20. In this case, the charging device 30 can supply electric power to a plurality of vehicles 20 at the same time.

As described above, the charging device 30 is configured to be connectable to the system power supply 11, the power storage device 12, and the vehicle 20 (specifically, the vehicle power storage device 21). Then, the charging device 30 charges the vehicle power storage device 21 by using at least one of the system power supply 11 and the power storage device 12. The detailed configuration of the charging device 30 will be described later.

The charging device 30 will be described in detail below.
As shown in FIG. 1, the charging device 30 includes a filter circuit 50, a first transformer 60, a second transformer 70, a primary side circuit 80, and a booster circuit 90 as a first secondary side circuit. A step-down circuit 100 as a second secondary circuit and a control ECU 120 are provided.

The filter circuit 50 reduces noise included in the system power Pa input from the system input terminals 31 to 33. The filter circuit 50 is an LC circuit having, for example, a filter inductor 51 and a filter capacitor 52. However, the present invention is not limited to this, and the specific configuration of the filter circuit 50 is arbitrary.

The first transformer 60 has a first primary winding 61 and a first secondary winding 62. That is, the first transformer 60 is a so-called insulated type.
The first secondary winding 62 has a first intermediate tap 62a. The first intermediate tap 62a is connected to the power storage device 12. Specifically, the first intermediate tap 62a is connected to the positive electrode storage input terminal 34. As a result, the first intermediate tap 62a is connected to the positive electrode terminal of the power storage device 12.

The second transformer 70 has a second primary winding 71 and a second secondary winding 72. That is, the second transformer 70 is a so-called insulated type. The first primary winding 61 and the second primary winding 71 are connected in series.

The second secondary winding 72 has a second intermediate tap 72a. The second intermediate tap 72a is connected to the vehicle 20. Specifically, the second intermediate tap 72a is connected to the connector 40, and more specifically, to the positive electrode load input terminal 41.

The primary side circuit 80 is provided between the system input terminals 31 to 33 and both transformers 60 and 70. The primary side circuit 80 is connected to the system input terminals 31 to 33 via the filter circuit 50, and the system power Pa whose noise is reduced by the filter circuit 50 is input to the primary side circuit 80. The primary side circuit 80 is connected to a series connection body of both primary side windings 61 and 71.

The primary circuit 80 is, for example, a matrix converter. The primary side circuit 80 includes primary side coils 81u to 81w and primary side switching elements 82ua to 82wb. The primary side circuit 80 performs AC power conversion by periodically turning ON / OFF the primary side switching elements 82ua to 82wb.

The primary coil 81u to 81w are connected to the system input terminals 31 to 33 via the filter circuit 50 (specifically, the filter inductor 51).
The primary side switching elements 82ua to 82wb are bidirectional switching elements capable of turning both forward and reverse voltages on and off. The specific configuration of the primary side switching elements 82ua to 82wb is arbitrary, but it is preferable to have, for example, a plurality of IGBTs or MOSFETs and diodes connected in parallel with each other.

The primary side switching elements 82ua to 82wb are connected in series with the primary side upper arm switching elements 82ua, 82va, 82wa by the primary side upper arm switching elements 82ua, 82va, 82wa and the primary side connecting lines 83u, 83v, 83w. It is composed of connected primary side lower arm switching elements 82ub, 82vb, 82wb.

The series connection body of the primary side upper arm switching elements 82ua, 82va, 82wa and the primary side lower arm switching elements 82ub, 82vb, 82wb are connected in parallel with each other and of both primary side windings 61, 71. It is connected in parallel to the series connector. The primary side coils 81u, 81v, 81w are connected to the primary side connection lines 83u, 83v, 83w.

The booster circuit 90 boosts the power output from, for example, the power storage device 12. The booster circuit 90 includes a booster coil 91 as a first secondary coil provided between the first intermediate tap 62a, which is an intermediate tap of the first secondary winding 62, and the power storage device 12. , A step-up switching element 92 to 95 as a first secondary side switching element connected to the first secondary side winding 62.

The boost coil 91 is provided on the wiring connecting the first intermediate tap 62a and the positive electrode storage input terminal 34.
The step-up switching elements 92 to 95 are, for example, n-type MOSFETs and IGBTs. However, the present invention is not limited to this, and the specific configuration of the step-up switching elements 92 to 95 is arbitrary.

The step-up switching elements 92 to 95 are, for example, the step-up upper arm switching elements 92, 94 and the step-up lower arm switching elements 93, 95 connected in series with the step-up upper arm switching elements 92, 94 via the step-up connection lines 96, 97. It is composed of and.

One end of the first secondary winding 62 is connected to the first boost connection line 96, and the other end of the first secondary winding 62 is connected to the second boost connection line 97. As a result, the step-up switching elements 92 to 95 are connected to the first secondary winding 62.

The booster circuit 90 is a first booster wiring 98 and a second booster wiring 99 that connect a series connection body of both first booster switching elements 92 and 93 and a series connection body of both second booster switching elements 94 and 95 in parallel. have. The first booster wiring 98 connects both booster upper arm switching elements 92 and 94, and the second booster wiring 99 connects both booster lower arm switching elements 93 and 95. The second booster wiring 99 is connected to the negative electrode wiring 44.

The step-down circuit 100 steps down the DC power output from, for example, the step-up circuit 90. The step-down circuit 100 includes a step-down coil 101 as a second secondary coil provided between the second intermediate tap 72a, which is an intermediate tap of the second secondary winding 72, and the vehicle power storage device 21. , The step-down switching elements 102 to 105 as the second secondary side switching element connected to the second secondary side winding 72 are provided.

The step-down coil 101 is provided on the wiring connecting the second intermediate tap 72a and the positive electrode load input terminal 41.
The step-down switching elements 102 to 105 are, for example, n-type MOSFETs and IGBTs. However, the present invention is not limited to this, and the specific configuration of the step-down switching elements 102 to 105 is arbitrary.

The step-down switching elements 102 to 105 are, for example, the step-down upper arm switching elements 102, 104 and the step-down lower arm switching elements 103, 105 connected in series with the step-down upper arm switching elements 102, 104 via the step-down connecting lines 106, 107. It is composed of and.

One end of the second secondary winding 72 is connected to the first step-down connection line 106, and the other end of the second secondary winding 72 is connected to the second step-down connection line 107. As a result, the step-down switching elements 102 to 105 are connected to the second secondary winding 72.

The step-down circuit 100 is a first step-down wiring 108 and a second step-down wiring 109 that connect a series connection body of both first step-down switching elements 102 and 103 and a series connection body of both second step-down switching elements 104 and 105 in parallel. have. The first step-down wiring 108 connects both step-down upper arm switching elements 102 and 104, and the second step-down wiring 109 connects both step-down lower arm switching elements 103 and 105.

The step-up circuit 90 and the step-down circuit 100 are connected. Specifically, the first step-down wiring 108 and the first step-up wiring 98 are connected, and the second step-down wiring 109 and the second step-up wiring 99 are connected. As a result, the electric power output from the step-up circuit 90 is input to the step-down circuit 100, and the step-down circuit 100 performs conversion to lower the voltage value.

The charging device 30 includes an intermediate capacitor 110 provided between the step-up circuit 90 and the step-down circuit 100. One end of the intermediate capacitor 110 is connected to the first step-up wiring 98 and the first step-down wiring 108, and the other end of the intermediate capacitor 110 is connected to the second step-up wiring 99 and the second step-down wiring 109.

In such a configuration, it can be said that the step-up switching elements 92 to 95 are connected to the step-down circuit 100 (specifically, the step-down switching elements 102 to 105) via the intermediate capacitor 110. Further, it can be said that the step-down switching elements 102 to 105 are connected to the step-up circuit 90 (specifically, the step-up switching elements 92 to 95) via the intermediate capacitor 110.

The control ECU 120 controls the primary side circuit 80, the step-up circuit 90, and the step-down circuit 100. The control ECU 120 controls the primary side switching elements 82ua to 82wb, the step-up switching elements 92 to 95, and the step-down switching elements 102 to 105, thereby using at least one of the system power supply 11 and the power storage device 12 for the vehicle. It is configured to charge the power storage device 21.

The specific hardware configuration of the control ECU 120 is arbitrary. For example, the control ECU 120 may be configured to have a dedicated hardware circuit for performing switching control, or may perform switching control based on a memory in which a control program for performing switching control and necessary information are stored, and a control program. It may be configured to have a CPU to perform.

The charging device 30 includes a power supply voltage sensor 121 that detects the power supply voltage Vp, and a charging voltage sensor 122 that detects the charging voltage Vr. The power supply voltage sensor 121 detects the power supply voltage Vp by detecting the voltage between the two storage input terminals 34 and 35, and outputs the detection result to the control ECU 120. The charging voltage sensor 122 detects the charging voltage Vr by detecting the voltage between the two load input terminals 41 and 42, and outputs the detection result to the control ECU 120. As a result, the control ECU 120 can grasp the power supply voltage Vp and the charging voltage Vr.

Further, the control ECU 120 is connected to the vehicle ECU 22 via the control terminal 43, and can communicate with the vehicle ECU 22. For example, the vehicle ECU 22 notifies the control ECU 120 of the required power. The control ECU 120 controls the primary side circuit 80, the step-up circuit 90, and the step-down circuit 100 so as to supply the same power as the required power or a power close to the required power.

The switching control by the control ECU 120 will be described in detail below.
The charging device 30 of the present embodiment uses, as a charging mode for charging the vehicle power storage device 21, a system mode for charging the vehicle power storage device 21 using at least the system power supply 11 and a power power storage device 12. It has a power supply mode for charging the vehicle power storage device 21. The grid mode includes a first grid mode in which the grid power supply 11 is used and a second grid mode in which both the grid power supply 11 and the power storage device 12 are used. The control ECU 120 controls the charging mode by controlling the primary side switching elements 82ua to 82wb, the step-up switching elements 92 to 95, and the step-down switching elements 102 to 105.

Specifically, in the system mode, the control ECU 120 periodically turns on / off the primary side switching elements 82ua to 82wb, the step-up switching elements 92 to 95, and the step-down switching elements 102 to 105, so that the system power supply 11 or , The system power supply 11 and the power storage device 12 are used to charge the vehicle power storage device 21.

Specifically, the control ECU 120 periodically turns ON / OFF the primary side switching elements 82ua to 82wb so that the power conversion of the system power Pa is performed.
Then, in the control ECU 120, the AC power output from the first transformer 60 is converted into DC power, and the intermediate voltage Vm input to the intermediate capacitor 110 becomes a value higher than the power supply voltage Vp and the charging voltage Vr. The step-up switching elements 92 to 95 are periodically turned ON / OFF.

The intermediate voltage Vm is set to a voltage higher than the maximum power supply voltage Vpmax. Further, the intermediate voltage Vm of the present embodiment is a voltage higher than the charging voltage Vr, and is specifically set higher than the maximum charging voltage Vrmax. The control ECU 120 controls the duty ratios of the step-up switching elements 92 to 95 in correspondence with the voltage ratio between the intermediate voltage Vm and the power supply voltage Vp.

The control ECU 120 periodically turns on / off the step-down switching elements 102 to 105 so that the DC power of the intermediate voltage Vm is converted into the DC power of the charging voltage Vr. That is, in the system mode, the control ECU 120 controls the booster circuit 90 so that the intermediate voltage Vm is higher than the power supply voltage Vp and the charging voltage Vr, and the DC power of the intermediate voltage Vm becomes the DC power of the charging voltage Vr. The step-down circuit 100 is controlled in this way.

The switching modes of the step-up switching elements 92 to 95 and the step-down switching elements 102 to 105 are arbitrary, but for example, the control ECU 120 uses the switching patterns of the step-up switching elements 92 to 95 as the first pattern and the second pattern. Switch alternately. In the first pattern, the first boosting upper arm switching element 92 and the second boosting lower arm switching element 95 are in the ON state, and the first boosting lower arm switching element 93 and the second boosting upper arm switching element 94 are in the OFF state. It is a switching pattern. In the second pattern, the first booster upper arm switching element 92 and the second booster lower arm switching element 95 are in the OFF state, and the first booster lower arm switching element 93 and the second booster arm switching element 94 are in the ON state. It is a switching pattern.

Here, the current flowing from the step-down circuit 100 toward the vehicle power storage device 21 changes according to the duty ratio of the step-down switching elements 102 to 105. Therefore, the control ECU 120 can control the electric power for charging the vehicle power storage device 21 by controlling the duty ratios of the step-down switching elements 102 to 105.

Further, when the power input from the system power supply 11 to the step-down circuit 100 is smaller than the power output from the step-down circuit 100, the power of the power storage device 12 is stepped down via the step-up circuit 90 so as to make up for the shortage. It is input to the circuit 100. On the other hand, when the power input from the system power supply 11 to the step-down circuit 100 is equal to or greater than the power output from the step-down circuit 100, the power of the power storage device 12 is not input to the step-down circuit 100. Then, the electric power input from the system power supply 11 to the step-down circuit 100 via the step-up circuit 90 changes according to the duty ratio of the primary side switching elements 82ua to 82wb. Therefore, the charging mode can be switched between the first system mode and the second system mode by controlling the duty ratios of the primary side switching elements 82ua to 82wb in correspondence with the electric power output from the step-down circuit 100. ..

According to such a configuration, the system power Pa input to the charging device 30 is boosted by the primary side circuit 80 and the first transformer 60 and input to the booster circuit 90. Then, the electric power input to the booster circuit 90 is rectified and stepped down by the booster circuit 90 and the intermediate capacitor 110. Further, if necessary, the power of the power storage device 12 is boosted to the DC power of the intermediate voltage Vm and input to the intermediate capacitor 110. As a result, DC power with an intermediate voltage of Vm is input to the intermediate capacitor 110. In this case, it can be said that the DC power output from the booster circuit 90 is stabilized by the intermediate capacitor 110.

Then, the DC power of the intermediate voltage Vm whose voltage is stabilized by the intermediate capacitor 110 is input to the step-down circuit 100, is stepped down to the charging voltage Vr by the step-down circuit 100, and is input to the vehicle power storage device 21. As a result, power is supplied to the vehicle power storage device 21 using at least the system power supply 11, that is, the vehicle power storage device 21 is charged.

The primary side circuit 80 adjusts the system power Pa (in other words, the power input from the system power supply 11 to the step-down circuit 100) by periodically turning ON / OFF the primary side switching elements 82ua to 82wb. It can be said that it is configured to do so.

Next, the power mode will be described.
In the power supply mode, the control ECU 120 periodically turns on / off both the step-up switching elements 92 to 95 and the step-down switching elements 102 to 105 to charge the power storage device 12.

Specifically, the control ECU 120 controls the booster circuit 90 (specifically, the boost switching elements 92 to 95) so that the intermediate voltage Vm becomes higher than the power supply voltage Vp and the charging voltage Vr. That is, the control ECU 120 uses the booster circuit 90 to boost-convert the DC power of the power supply voltage Vp into the DC power of the intermediate voltage Vm. The control of the intermediate voltage Vm is realized by controlling the duty ratios of the step-up switching elements 92 to 95.

Then, the control ECU 120 converts the DC power of the intermediate voltage Vm into the DC power of the charging voltage Vr, and the required power (power supply target power Pbt) is input to the vehicle power storage device 21 so that the step-down circuit 100 ( In detail, the duty ratio of the step-down switching elements 102 to 105) is controlled.

On the other hand, in the power supply mode, the control ECU 120 does not periodically turn ON / OFF the primary side switching elements 82ua to 82wb, but always keeps them OFF. That is, it can be said that the control ECU 120 turns off the primary side switching elements 82ua to 82wb so that the system power Pa is not transmitted to both transformers 60 and 70 when the charging mode is the power supply mode.

Here, in the present embodiment, when the vehicle 20 is connected to the connector 40, the control ECU 120 executes a charge control process for charging the vehicle power storage device 21. In the charge control process, the control ECU 120 controls the charge mode based on the target SOCXa which is the SOC of the vehicle power storage device 21 and the power supply SOCXb which is the SOC of the power power storage device 12.

Hereinafter, the charge control process will be described with reference to FIG.
As shown in FIG. 2, the control ECU 120 first grasps the required power Prq, which is the power suitable for charging the vehicle power storage device 21 at the present stage, in step S101.

Here, as shown in FIG. 3, the required power Prq fluctuates according to the target SOCXa. Specifically, the required power Prq is a constant value of the first power Prq1 when the target SOCXa is equal to or less than the first target value Xa1, and gradually decreases when the target SOCXa becomes larger than the first target value Xa1. Then, when the required power Prq is equal to or higher than the second target value Xa2, the required power Prq becomes the second power Prq2 having a constant value again. The second power Prq2 is smaller than the first power Prq1.

That is, the electric power suitable for charging the vehicle power storage device 21 is the first electric power Prq1 when the target SOCXa is the first target value Xa1 or less, and when the target SOCXa is the second target value Xa2 or more. It is the second electric power Prq2, and decreases from the first target value Xa1 toward the second target value Xa2.

In the present embodiment, as shown in FIG. 3, the system maximum power Pamax and the power supply maximum power Pbmax, which is the maximum power that can be output by the power storage device 12, are set between the first power Prq1 and the second power Prq2. Has been done. That is, the system maximum power Pamax and the power supply maximum power Pbmax are larger than the second power Prq2 and smaller than the first power Prq1. The maximum power source power Pbmax is determined by the specifications and standards of the power storage device 12.

Here, among the target SOCXa, the SOC in which the required power Prq is the system maximum power Pamax is referred to as the system target threshold value Xat1. In the present embodiment, since the system maximum power Pamax fluctuates depending on the situation, the system target threshold value Xat1 may fluctuate.

Further, among the target SOCXa, the SOC in which the required power Prq is the maximum power power Pbmax is referred to as the power supply target threshold value Xat2. The magnitude relationship between the system maximum power Pamax and the power supply maximum power Pbmax is arbitrary. Further, the system maximum power Pamax and the power supply maximum power Pbmax may be the same.

In step S101, the control ECU 120 grasps the current target SOCXa, and grasps the required power Prq corresponding to the current target SOCXa from the grasping result.
The specific configuration for grasping the target SOCXa is arbitrary, but for example, the control ECU 120 may be configured to estimate the target SOCXa based on the charging voltage Vr detected by the charging voltage sensor 122, or may be configured to estimate the target SOCXa by communication with the vehicle ECU 22. It may be configured to acquire the target SOCXa.

Further, the configuration for grasping the required power Prq from the target SOCXa is arbitrary, but for example, the control ECU 120 has map data in which the target SOCXa and the required power Prq are associated with each other, and by referring to the map data, the control ECU 120 has. The required power Prq corresponding to the target SOCXa may be grasped.

As shown in FIG. 2, the control ECU 120 proceeds to step S102 after the execution of step S101, and determines whether or not the required power Prq grasped this time is equal to or less than the supplyable power Pmax.

The power that can be supplied, Pmax, is the maximum power that can be supplied by using both the system power supply 11 and the power storage device 12. Specifically, the supplyable power Pmax is the combined power of the system maximum power Pamax and the power supply maximum power Pbmax.

When the required power Prq is equal to or less than the supplyable power Pmax, the control ECU 120 sets the target power Pt to the required power Prq in step S103 and proceeds to step S105.

On the other hand, when the required power Prq is larger than the supplyable power Pmax, the control ECU 120 sets the target power Pt to the supplyable power Pmax in step S104 and proceeds to step S105.

In step S105, the control ECU 120 determines whether or not the target power Pt is equal to or less than the system maximum power Pamax.
Here, pay attention to the point that the target SOCXa having the system maximum power Pamax is the system target threshold value Xat1 and the required power Prq (in other words, the target power Pt) becomes smaller when the target SOCXa becomes higher than the system target threshold value Xat1. Therefore, the process of step S105 can be said to be a process of determining whether or not the target SOCXa is equal to or higher than the system target threshold value Xat1.

The control ECU 120 sets the charging mode to the first system mode when the target power Pt is equal to or less than the system maximum power Pamax, in other words, when the target SOCXa is equal to or more than the system target threshold value Xat1. Specifically, in step S106, the control ECU 120 sets the system target power Pat, which is the target value of the system power Pa output from the system power supply 11, to the target power Pt. Then, in step S107, the control ECU 120 sets the power supply target power Pbt, which is the target value of the power supply power Pb output from the power storage device 12, to “0”, and proceeds to step S114.

On the other hand, when the target power Pt is larger than the system maximum power Pamax, in other words, when the target SOCXa is lower than the system target threshold value Xat1, the control ECU 120 changes the charging mode to the second system mode in steps S108 and S109. Execute the setting process.

Specifically, the control ECU 120 sets the system target power Pat to the system maximum power Pamax in step S108. Then, in step S109, the control ECU 120 sets the power supply target power Pbt to a value obtained by subtracting the system maximum power Pamax from the target power Pt.

After that, the control ECU 120 proceeds to step S110 to determine whether or not the power storage device 12 can be discharged. Specifically, the control ECU 120 grasps the power supply SOCXb which is the SOC of the current power storage device 12, and determines whether or not the power supply SOCXb is equal to or higher than a predetermined power supply threshold value Xbt.

The power threshold value Xbt is arbitrary and includes, for example, "0". Further, the power supply threshold value Xbt may be a variable value that changes according to the target SOCXa. For example, the power supply threshold value Xbt may be set to increase as the target SOCXa decreases, in response to the fact that the amount of discharge from the power storage device 12 tends to increase as the target SOCXa decreases.

In step S110, the control ECU 120 may determine whether or not the power supply voltage Vp is equal to or higher than a predetermined threshold voltage. In this case, the threshold voltage may be set to a voltage corresponding to the power supply threshold Xbt. Focusing on the fact that the power supply SOCXb and the power supply voltage Vp correspond to each other, it is determined whether or not the power supply voltage Vp is equal to or higher than the threshold voltage and whether or not the power supply SOCXb is equal to or higher than the power supply threshold value Xbt. Is equivalent to.

When the power supply SOCXb is equal to or higher than the power supply threshold value Xbt, the control ECU 120 determines that the power storage device 12 can be discharged, and proceeds to step S114 while maintaining the charging mode in the second system mode.

On the other hand, when the power supply SOCXb is lower than the power supply threshold value Xbt, the control ECU 120 changes the target power Pt and changes the charging mode from the second system mode to the first system mode. Specifically, the control ECU 120 changes the target power Pt to the system target power Pat in step S111, and sets the system target power Pat to the system maximum power Pamax in step S112. Then, the control ECU 120 sets the power supply target power Pbt to “0” in step S113, and proceeds to step S114. In this embodiment, setting the power supply target power Pbt to "0" means setting the charging mode to the first system mode.

In step S114, the control ECU 120 controls switching of the primary side switching elements 82ua to 82wb, the step-up switching elements 92 to 95, and the step-down switching elements 102 to 105 so that the target power Pt is input to the vehicle power storage device 21. conduct.

Specifically, when the charging mode is the first system mode, the control ECU 120 controls the duty ratios of the primary side switching elements 82ua to 82wb so that the target power Pt is supplied from the system power supply 11. As a result, the grid power Pa becomes the target power Pt.

Then, the control ECU 120 controls the duty ratios of the step-up switching elements 92 to 95 so that rectification and voltage conversion are performed, and the step-down switching elements 102 to 105 so that the target power Pt is input to the vehicle power storage device 21. Controls the duty ratio of.

Further, in the control ECU 120, when the charging mode is the second system mode, the system target power Pat is supplied from the system power supply 11 and the power supply target power Pbt is supplied from the power storage device 12, and the DC of the target power Pt. The switching elements 82ua to 82wb, 92 to 95, 102 to 105 are controlled so that the electric power is input to the vehicle power storage device 21.

Specifically, the control ECU 120 controls the duty ratio of the primary side switching elements 82ua to 82wb so that the system target power Pat is supplied from the system power supply 11. As a result, the grid power Pa becomes the grid target power Pat.

Then, the control ECU 120 controls the duty ratios of the step-up switching elements 92 to 95 so that rectification and voltage conversion are performed, and the step-down switching elements 102 to 105 so that the target power Pt is input to the vehicle power storage device 21. Controls the duty ratio of. As a result, the power supply power Pb output from the power storage device 12 becomes the power supply target power Pbt.

After that, the control ECU 120 determines in step S115 whether or not the charging end condition is satisfied. The charging end condition is, for example, that the target SOCXa is 100%. However, the charging end condition is arbitrary, and may be, for example, that a predetermined period has elapsed or that the charging end operation has been performed on the charging device 30.

When the charging end condition is satisfied, the control ECU 120 proceeds to step S116, executes a process of stopping charging, and ends the main charge control process. Specifically, the control ECU 120 stops periodic ON / OFF of each switching element 82ua to 82wb, 92 to 95, 102 to 105.

On the other hand, if the charging end condition is not satisfied, the control ECU 120 returns to step S101. As a result, the control ECU 120 again grasps the required power Prq corresponding to the current target SOCXa and sets the charging mode. That is, the control ECU 120 repeatedly grasps the required power Prq until the charging end condition is satisfied, sets the charging mode corresponding to the grasped result, and uses the required power Prq or the system maximum power Pamax to determine the vehicle power storage device 21. It is controlled so that charging is performed.

Next, the operation of this embodiment will be described with reference to the example shown in FIG. FIG. 4 is a graph showing an example of time changes of the target power Pt, the system target power Pat, and the power supply target power Pbt. In the example of FIG. 4, it is assumed that the power storage device 12 can be discharged, and the charging start timing is set to “0”.

When the target SOCXa at the charging start timing is equal to or less than the first target value Xa1, the target power Pt is set to the first power Prq1. In this case, since the target SOCXa is lower than the system target threshold value Xat1, the second system mode is set as the charging mode. Then, the system target power Pat is set to the system maximum power Pamax, the system maximum power Pamax is supplied from the system power supply 11, and the difference between the first power Prq1 and the system maximum power Pamax is used as the power supply power Pb. It is supplied from 12. As a result, the first electric power Prq1 is supplied to the vehicle power storage device 21.

After that, the target SOCXa becomes higher as the vehicle power storage device 21 is charged. Then, the required power Prq becomes smaller from the timing of t1 when the target SOCXa becomes higher than the first target value Xa1. In this case, the system power Pa is maintained at the system maximum power Pamax, and the power supply power Pb becomes smaller, so that the power input to the vehicle power storage device 21 becomes smaller. That is, in the second system mode, the control ECU 120 of the present embodiment follows the change of the required power Prq by variably controlling the power supply power Pb while maintaining the system power Pa at the system maximum power Pamax.

After that, at the timing of t2 when the target SOCXa becomes the system target threshold value Xat1, the charging mode is switched from the second system mode to the first system mode, and the vehicle power storage device 21 is charged using only the system power supply 11. .. Then, for example, at the timing of t3 when the target SOCXa becomes 100%, the charging of the vehicle power storage device 21 is completed.

According to the present embodiment described in detail above, the following effects are obtained.
(1-1) The power system 10 uses at least one of the system power supply 11 and the power storage device 12 to charge the vehicle power storage device 21 as the target power storage device. The power system 10 has a first system mode in which the system power supply 11 is used, a second system mode in which both the system power supply 11 and the power storage device 12 are used, and a power storage mode as charging modes for charging the vehicle power storage device 21. It includes a charging device 30 having a power supply mode using the device 12, and a control ECU 120 as a control unit for controlling the charging mode.

The control ECU 120 controls the charging mode based on the target SOCXa which is the SOC of the vehicle power storage device 21 and the power supply SOCXb which is the SOC of the power power storage device 12, and is during charging of the vehicle power storage device 21. The charging mode is switched according to the change of the target SOCXa.

According to this configuration, since the charging mode for charging the vehicle power storage device 21 includes the first system mode, the second system mode, and the power supply mode, either the system power supply 11 or the power storage device 12 is used. The vehicle power storage device 21 can be charged, or the vehicle power storage device 21 can be charged using both the system power supply 11 and the power supply power storage device 12. Further, by controlling the charging mode based on the target SOCXa and the power supply SOCXb, it is possible to select an appropriate charging mode according to the situation.

In particular, the SOC of the vehicle power storage device 21 changes during charging of the vehicle power storage device 21. When the SOC of the vehicle power storage device 21 changes, the electric power suitable for charging the vehicle power storage device 21 also changes. In this regard, according to this configuration, since the charging mode is switched according to the change in the SOC of the vehicle power storage device 21 while the vehicle power storage device 21 is being charged, the vehicle power storage is accompanied by the change in the SOC of the vehicle power storage device 21. The charging mode can be made to follow a change in power suitable for charging the device 21. Therefore, the vehicle power storage device 21 can be suitably charged.

(1-2) When the target SOCXa is lower than the predetermined system target threshold value Xat1 and the power supply SOCXb is equal to or higher than the predetermined power supply threshold value Xbt, the control ECU 120 sets the charging mode to the second system mode. .. On the other hand, when the target SOCXa is equal to or higher than the system target threshold value Xat1, the control ECU 120 sets the charging mode to the first system mode.

According to this configuration, when the target SOCXa is low, the power suitable for charging tends to be large, and when the target SOCXa is lower than the system target threshold value Xat1 and the power supply SOCXb is equal to or higher than the power supply threshold value Xbt, charging is performed. The mode is set to the second system mode. As a result, the vehicle power storage device 21 can be charged using both the system power supply 11 and the power power storage device 12, so that a large amount of electric power can be supported.

Further, as a condition for setting the charging mode to the second system mode, it is included that the power supply SOCXb is equal to or higher than the power supply threshold value Xbt. As a result, inconveniences caused by the discharge of the power storage device 12 even though the power storage amount of the power storage device 12 is small, for example, sufficient power supply cannot be performed, or the power storage device cannot be supplied with sufficient power. It is possible to prevent the 12 from deteriorating.

On the other hand, when the target SOCXa is higher than the target SOCXa, the power suitable for charging tends to be smaller, and when the target SOCXa is equal to or higher than the system target threshold value Xat1, the charging mode is set to the first system mode. As a result, it is possible to supply electric power suitable for charging without using the power storage device 12.

(1-3) When the target SOCXa is lower than the system target threshold value Xat1 and the power supply SOCXb is lower than the power supply threshold value Xbt, the control ECU 120 sets the charging mode to the first system mode.

According to this configuration, even if the target SOCXa is lower than the system target threshold value Xat1, if the power supply SOCXb is lower than the power supply threshold value Xbt, only the system power supply 11 is used without using the power storage device 12. It is used to charge the vehicle power storage device 21. As a result, the vehicle power storage device 21 can be charged while suppressing the inconvenience caused by the discharge of the power power storage device 12 even though the power storage amount of the power power storage device 12 is small.

(1-4) The electric power suitable for charging the vehicle power storage device 21 is the first electric power Prq1 when the target SOCXa is equal to or less than the predetermined first target value Xa1, and the target SOCXa is the first target value. When the second target value is Xa2 or higher, which is higher than Xa1, the second power is Prq2. Then, the electric power suitable for charging the vehicle power storage device 21 decreases from the first target value Xa1 to the second target value Xa2. The system maximum power Pamax, which is the maximum power that the system power supply 11 can output, is higher than the first power Prq1 and lower than the second power Prq2, and the system target threshold value Xat1 is suitable for charging the vehicle power storage device 21. This is the target SOCXa whose power is the maximum power of the system Pamax.

According to this configuration, the charging mode is the second system mode until the power suitable for charging the vehicle power storage device 21 reaches the system maximum power Pamax, and the power suitable for charging the vehicle power storage device 21 is the system maximum power. When it becomes smaller than Pamax, the charging mode is switched from the second system mode to the first system mode. Thereby, the vehicle power storage device 21 can be suitably charged under the condition that the system maximum power Pamax is set between the first power Prq1 and the second power Prq2.

(1-5) When the charging mode is the second system mode, the control ECU 120 is output from the power storage device 12 while maintaining the system power Pa at the system maximum power Pamax according to the change of the target SOCXa. The power supply power Pb is variably controlled.

According to such a configuration, since the system power Pa is maintained at the system maximum power Pamax, the power supply power Pb can be reduced as much as possible. As a result, charging / discharging of the power storage device 12 can be suppressed, and deterioration of the power storage device 12 can be suppressed through the charging / discharging.

(1-6) The power supply threshold value Xbt is set to increase as the target SOCXa decreases.
According to this configuration, the lower the target SOCXa, the larger the amount of electricity stored in the power storage device 12 required for charging the vehicle power storage device 21, and the power threshold value Xbt becomes lower as the target SOCXa becomes lower. It is set to be high. As a result, it is possible to suppress inconveniences such as exhaustion of the stored amount of the power storage device 12 in the middle of the second system mode.

(1-7) The charging device 30 includes a first transformer 60 having a first primary winding 61 and a first secondary winding 62, and a second primary winding 71 and a second. It includes a second transformer 70 having a secondary winding 72. Both primary windings 61 and 71 are connected in series. The first secondary winding 62 has a first intermediate tap 62a to which the power storage device 12 is connected. The second secondary winding 72 has a second intermediate tap 72a to which the vehicle power storage device 21 is connected.

The charging device 30 is a primary side circuit 80 which is a power conversion circuit connected to a system power supply 11 and connected to a series connection body of both primary side windings 61 and 71, and as a first secondary side circuit. It includes a step-up circuit 90, a step-down circuit 100 as a second secondary circuit, and an intermediate capacitor 110 provided between the step-up circuit 90 and the step-down circuit 100. The primary side circuit 80 has primary side switching elements 82ua to 82wb. The booster circuit 90 is connected to a booster coil 91 as a first secondary coil provided between the first intermediate tap 62a and the power storage device 12 and a first secondary winding 62. The step-up switching elements 92 to 95 as the secondary side switching element of No. 1 are provided. The step-down circuit 100 is connected to a step-down coil 101 as a second secondary side coil provided between the second intermediate tap 72a and the vehicle power storage device 21 and a second secondary winding 72. The step-down switching elements 102 to 105 as the secondary side switching element of No. 2 are provided. The control ECU 120 controls the charging mode by controlling each switching element 82ua to 82wb, 92 to 95, 102 to 105.

According to such a configuration, by controlling each of the switching elements 82ua to 82wb, 92 to 95, 102 to 105, it is possible to charge the vehicle power storage device 21 while controlling the charging mode.

(Second Embodiment)
In this embodiment, the charge control process is different from that in the first embodiment. The difference will be described with reference to FIG.

As shown in FIG. 5, after executing the process of step S103 or step S104, the control ECU 120 determines in step S201 whether or not the vehicle power storage device 21 can be discharged. The determination process of step S201 is the same as the process of step S110 of the first embodiment.

When the control ECU 120 determines that the vehicle power storage device 21 cannot be discharged, in detail, when the power supply SOCXb is lower than the power supply threshold value Xbt, the control ECU 120 sets the charging mode to the first system mode. Specifically, the control ECU 120 proceeds to step S202 and determines whether or not the target power Pt is equal to or less than the system maximum power Pamax.

When the target power Pt is equal to or less than the system maximum power Pamax, the control ECU 120 sets the system target power Pat to the target power Pt in step S203, and proceeds to step S206.

On the other hand, when the target power Pt is larger than the system maximum power Pamax, the control ECU 120 proceeds to step S204 and changes the target power Pt to the system maximum power Pamax. Then, the control ECU 120 sets the system target power Pat to the system maximum power Pamax in step S205, and proceeds to step S206.

In step S206, the control ECU 120 sets the power supply target power Pbt to “0”. As a result, the charging mode is set to the first system mode. After that, the control ECU 120 proceeds to step S114.

As shown in FIG. 5, when the power storage device 12 can be discharged, specifically, when the power supply SOCXb is equal to or higher than the power supply threshold value Xbt, the control ECU 120 positively determines step S201 and proceeds to step S207. , It is determined whether or not the target power Pt is equal to or less than the maximum power supply power Pbmax.

Here, as already described, the value of the target SOCXa in which the required power Prq is the power supply maximum power Pbmax is referred to as the power supply target threshold value Xat2. Focusing on the power supply target threshold value Xat2 and the point that the required power Prq (in other words, the target power Pt) becomes lower when the target SOCXa becomes higher than the power supply target threshold value Xat2, the control ECU 120 has the target SOCXa in step S207. It can be said that it is determined whether or not the power supply target threshold value is Xat2 or higher.

The control ECU 120 sets the charging mode to the power supply mode when the target power Pt is equal to or less than the maximum power supply power Pbmax, in other words, when the target SOCXa is equal to or greater than the power supply target threshold value Xat2. Specifically, in step S208, the control ECU 120 sets the power supply target power Pbt, which is the target value of the power supply power Pb output from the power storage device 12, to the target power Pt. Then, in step S209, the control ECU 120 sets the system target power Pat, which is the target value of the system power Pa output from the system power supply 11, to “0”, and proceeds to step S209. In the present embodiment, setting the system target power Pat to "0" means setting the charging mode to the power supply mode.

On the other hand, when the target power Pt is larger than the power supply maximum power Pbmax, in other words, when the target SOCXa is lower than the power supply target threshold value Xat2, the control ECU 120 sets the charging mode to the second system mode in steps S210 and S211. Execute the setting process.

Specifically, the control ECU 120 sets the power supply target power Pbt to the power supply maximum power Pbmax in step S210. Then, in step S211 the control ECU 120 sets the system target power Pat to a value obtained by subtracting the power supply maximum power Pbmax from the target power Pt, and proceeds to step S114. Since the processing after step S114 is the same as that of the first embodiment, detailed description thereof will be omitted.

Next, the operation of this embodiment will be described.
When the power supply SOCXb is lower than the power supply threshold value Xbt, the charging mode is set to the first system mode. As a result, the vehicle power storage device 21 is charged using only the system power supply 11.

On the other hand, when the power supply SOCXb is equal to or higher than the power supply threshold value Xbt, the charging mode is set to either the power supply mode or the second system mode. Specifically, when the target SOCXa is equal to or higher than the power supply target threshold value Xat2, the charging mode is set to the power supply mode, and when the target SOCXa is lower than the power supply target threshold value Xat2, the charging mode is set to the second system mode. Will be done.

According to the present embodiment described in detail above, the following effects are exhibited in place of the effects such as (1-2).
(2-1) The control ECU 120 sets the charging mode to the second system mode when the target SOCXa is lower than the power supply target threshold value Xat2 in a situation where the power supply SOCXb is equal to or higher than a predetermined power supply threshold value Xbt. On the other hand, the control ECU 120 sets the charging mode to the power supply mode when the target SOCXa is the power supply target threshold value Xat2 or more in the situation where the power supply SOCXb is the power supply threshold value Xbt or more.

According to this configuration, when the target SOCXa is low, the power suitable for charging tends to be large, and when the power supply SOCXb is equal to or higher than the power supply threshold value Xbt and the target SOCXa is lower than the power supply target threshold value Xat2, charging is performed. The mode is set to the second system mode. As a result, the vehicle power storage device 21 can be charged using both the system power supply 11 and the power power storage device 12, so that a large amount of electric power can be supported.

On the other hand, when the target SOCXa is higher than the target SOCXa, the power suitable for charging tends to be smaller, and when the target SOCXa is equal to or higher than the power supply target threshold value Xat2, the charging mode is set to the power supply mode. As a result, it is possible to supply electric power suitable for charging using only the power storage device 12.

Further, as a condition for setting the charging mode to the second system mode or the power supply mode, it is included that the power supply SOCXb is equal to or higher than the power supply threshold value Xbt. As a result, inconveniences caused by the discharge of the power storage device 12 even though the power storage amount of the power storage device 12 is small, for example, sufficient power cannot be supplied, or the power storage device cannot be supplied with sufficient power. It is possible to prevent the 12 from deteriorating.

(2-2) When the power supply SOCXb is lower than the power supply threshold value Xbt, the control ECU 120 sets the charging mode to the first system mode regardless of the target SOCXa.
According to this configuration, when the power supply SOCXb is lower than the power supply threshold value Xbt, the vehicle power storage device 21 is charged using only the system power supply 11 regardless of the target SOCXa. As a result, the vehicle power storage device 21 can be charged while suppressing the inconvenience caused by the discharge of the power power storage device 12 even though the power storage amount of the power power storage device 12 is small.

(2-3) The power supply maximum power Pbmax, which is the maximum power that can be output by the power storage device 12, is higher than the first power Prq1 and lower than the second power Prq2. The power supply target threshold value Xat2 is a target SOCXa in which the power suitable for charging the vehicle power storage device 21 is the power supply maximum power Pbmax.

According to this configuration, the charging mode is the second system mode until the electric power suitable for charging the vehicle power storage device 21 reaches the power supply maximum power Pbmax, and the power suitable for charging the vehicle power storage device 21 is the power supply maximum power. When it becomes smaller than Pbmax, the charging mode is switched from the second system mode to the power mode. As a result, under the condition that the maximum power source power Pbmax is set between the first power source Prq1 and the second power source Prq2, the vehicle power storage device 21 is charged while preferentially using the power power storage device 12. It can be preferably performed. Therefore, the burden on the system power supply 11 can be reduced.

More specifically, when the system power supply 11 is used not only for the main power system 10 but also for other devices, the burden on the system power supply 11 may vary depending on the usage status of the other devices and the contract details of the system power supply 11. That is, there is a case where it is desired to reduce the system power Pa drawn by the main power system 10. In this respect, according to this configuration, since the power storage device 12 is preferentially used over the system power supply 11, the system power Pa drawn by the power system 10 can be reduced. Therefore, the burden on the system power supply 11 can be reduced.

(Third Embodiment)
In the present embodiment, the configuration of the charging device 30 is different from that of the first embodiment. The difference will be described with reference to FIG.

As shown in FIG. 6, the charging device 30 of the present embodiment includes a filter circuit 50, an AC / DC conversion circuit 200, a first conversion circuit 230, a second conversion circuit 240, an intermediate capacitor 110, and a control ECU 120. And have.

Considering that the charging device 30 has one configuration of the power system 10, the power system 10 includes an AC / DC conversion circuit 200, a first conversion circuit 230, a second conversion circuit 240, and an intermediate capacitor 110. , It can be said that the control ECU 120 is provided.

The AC / DC conversion circuit 200 converts the system power Pa output from the system power supply 11 into DC power.
The AC / DC conversion circuit 200 of the present embodiment includes a transformer 201 having a primary winding 202 and a secondary winding 203, and a primary matrix converter 210 provided on the primary side of the transformer 201. , A secondary side full bridge circuit 220 provided on the secondary side with respect to the transformer 201. That is, the AC / DC conversion circuit 200 of this embodiment is a dual active bridge type matrix converter.

The primary side matrix converter 210 is connected to the primary side winding 202 and is also connected to the system input terminals 31 to 33. As a result, the primary side matrix converter 210 is connected to the system power supply 11 via the system input terminals 31 to 33. The primary side matrix converter 210 is configured to enable bidirectional conversion of AC power.

The primary side matrix converter 210 includes primary side switching elements 211 to 216. The primary side matrix converter 210 performs AC power conversion by periodically turning ON / OFF the primary side switching elements 211 to 216. For example, the primary side matrix converter 210 converts the grid power Pa into AC power of a predetermined voltage and outputs it to the primary side winding 202 of the transformer 201, or the AC power input from the transformer 201 is the system power. It is converted to Pa and output to the system power supply 11.

The primary side switching elements 211 and 216 are bidirectional switching elements capable of turning both forward and reverse voltages on and off. The specific configuration of the primary switching elements 211 to 216 is arbitrary, but it may have, for example, a plurality of IGBTs or MOSFETs and diodes connected in parallel with each other.

The primary side switching elements 211 and 216 are connected in series with the primary side upper arm switching elements 211,212, 213 by the primary side upper arm switching elements 211,212,213 and the primary side connecting lines 217,218,219. It is composed of connected primary side lower arm switching elements 214, 215 and 216. The series connection body of the primary side upper arm switching elements 211,212, 213 and the primary side lower arm switching elements 214,215,216 is connected to the primary side winding 202 in a state of being connected in parallel with each other. There is.

The system input terminals 31 to 33 are connected to the primary side connection lines 217 to 219 via the filter circuit 50. As a result, the system power Pa is input to the primary side matrix converter 210.

The transformer 201 is provided between the primary side matrix converter 210 and the secondary side full bridge circuit 220, and performs voltage conversion of AC power. The transformation ratio corresponds to the turns ratio between the primary winding 202 and the secondary winding 203.

The secondary side full bridge circuit 220 is connected to the secondary side winding 203 and the intermediate capacitor 110. The secondary side full bridge circuit 220 is configured to enable bidirectional conversion of AC / DC. The secondary side full bridge circuit 220 is a secondary side connected in series to the secondary side upper arm switching elements 221 and 222 and the secondary side upper arm switching elements 221 and 222 via the secondary side connection lines 225 and 226. It has lower arm switching elements 223 and 224. The secondary side switching elements 221 to 224 are, for example, n-type MOSFETs. However, the present invention is not limited to this, and the specific configuration of the secondary side switching elements 221 to 224 is arbitrary.

The secondary winding 203 is connected to the secondary connection lines 225 and 226. As a result, the AC power output from the transformer 201 (specifically, the secondary winding 203) is input to the secondary full bridge circuit 220.

The secondary side full bridge circuit 220 performs power conversion by periodically turning ON / OFF the secondary side switching elements 221 to 224. For example, the secondary side full bridge circuit 220 converts the AC power input from the transformer 201 into DC power, or converts the DC power input from the intermediate capacitor 110 side into AC power.

That is, the AC / DC conversion circuit 200 performs bidirectional conversion between AC power and DC power by periodically turning ON / OFF the primary side switching elements 211 to 216 and the secondary side switching elements 221 to 224. ..

The first conversion circuit 230 is a power conversion circuit connected to the power storage device 12. The first conversion circuit 230 of the present embodiment is, for example, a bidirectional converter capable of bidirectional conversion of DC power.

The first conversion circuit 230 includes, for example, first conversion switching elements 231 to 234. Specifically, the first conversion circuit 230 includes a first upper arm conversion switching element 231,232, a first lower arm conversion switching element 233, 234, and a first conversion connection line 235, 236 connecting both in series. , Is equipped. Both first conversion connection lines 235 and 236 are connected to the positive electrode storage input terminal 34, and both first lower arm conversion switching elements 233 and 234 are connected to the negative electrode storage input terminal 35. The first conversion circuit 230 has first conversion coils 237 and 238 provided on two lines connecting both first conversion connection lines 235 and 236 and the positive electrode storage input terminal 34.

The first conversion switching element 231 to 234 of the present embodiment has a diode that allows a current to flow in the opposite direction. The diode is, for example, a body diode of a MOSFET. However, the present invention is not limited to this, and the diode may be externally attached to the first conversion switching element 231 to 234.

The first conversion circuit 230 of the present embodiment is a booster circuit that boosts the DC power stored in the power storage device 12. The first conversion circuit 230 includes two circuits including a circuit having a first conversion switching element 231 and 233 and a first conversion coil 237, and a circuit having a first conversion switching element 232 and 234 and a first conversion coil 238. It is a bidirectional converter in which circuits are connected in parallel.

The first conversion circuit 230 performs bidirectional conversion of DC power by periodically turning ON / OFF the first conversion switching elements 231 to 234. For example, the first conversion circuit 230 boosts the DC power stored in the power storage device 12 and outputs it to the AC / DC conversion circuit 200 or the second conversion circuit 240, or the AC / DC conversion circuit 200 or the second conversion. The DC power input from the circuit 240 is stepped down and output to the power storage device 12.

For example, the switching pattern in which the first conversion switching elements 231 and 234 are in the ON state and the first conversion switching elements 232 and 233 are in the OFF state is set as the first pattern, and the first conversion switching elements 231 and 234 are in the OFF state. The switching pattern in which the first conversion switching elements 232 and 233 are in the ON state is defined as the second pattern. In this case, in the first conversion circuit 230, the first conversion switching elements 231 to 234 alternately switch between the first pattern and the second pattern to boost the DC power stored in the power storage device 12. do.

The second conversion circuit 240 has a second conversion switching element 241 to 244. Specifically, the second conversion circuit 240 includes a second upper arm conversion switching element 241,242, a second lower arm conversion switching element 243, 244, and a second conversion connection line 245, 246 that connects both in series. , Is equipped. Both second conversion connection lines 245 and 246 are connected to the positive electrode load input terminal 41, and both second lower arm conversion switching elements 243 and 244 are connected to the negative electrode load input terminal 42. As a result, the second conversion circuit 240 and the vehicle power storage device 21 are connected. The second conversion circuit 240 has second conversion coils 247 and 248 provided on a line connecting both second conversion connection lines 245 and 246 and the positive electrode load input terminal 41.

The second conversion circuit 240 is connected to both the AC / DC conversion circuit 200 and the first conversion circuit 230. Specifically, the charging device 30 includes a positive electrode wiring LN1 and a negative electrode wiring LN2 that connect the AC / DC conversion circuit 200 and the second conversion circuit 240. The positive electrode wiring LN1 and the negative electrode wiring LN2 include a secondary side full bridge circuit 220, a series connection of a second upper arm conversion switching element 241 and a second lower arm conversion switching element 243, a second upper arm conversion switching element 242, and a second upper arm conversion switching element 242. The second lower arm conversion switching element 244 is connected to the series connection body.

The first conversion circuit 230 is connected to the positive electrode wiring LN1 and the negative electrode wiring LN2. In this case, it can be said that the AC / DC conversion circuit 200 and the first conversion circuit 230 are connected to the second conversion circuit 240 in a state of being connected in parallel to each other.

The second conversion circuit 240 is a power conversion circuit, for example, a DC / DC converter circuit that performs voltage conversion of DC power. In the present embodiment, the second conversion circuit 240 is a bidirectional converter capable of bidirectional conversion of DC power. Specifically, the second conversion circuit 240 includes a circuit having a second conversion switching element 241,243 and a second conversion coil 247 connected in series with each other, and a second conversion switching element 242 connected in series with each other. It is a bidirectional converter in which a circuit having 244 and a second conversion coil 248 is connected in parallel.

The second conversion circuit 240 performs bidirectional conversion of DC power by periodically turning ON / OFF the second conversion switching elements 241 to 244. For example, the second conversion circuit 240 steps down at least one of the DC power input from the AC / DC conversion circuit 200 and the DC power input from the first conversion circuit 230 and outputs them to the vehicle power storage device 21. The DC power stored in the vehicle power storage device 21 is boosted and output to the AC / DC conversion circuit 200 or the first conversion circuit 230.

For example, the switching pattern in which the second conversion switching elements 241,244 are in the ON state and the second conversion switching elements 242 and 243 are in the OFF state is set as the first pattern, and the second conversion switching elements 241,244 are in the OFF state. The switching pattern in which the second conversion switching elements 242 and 243 are in the ON state is defined as the second pattern. In this case, the second conversion circuit 240 performs power conversion by alternately switching the first pattern and the second pattern in the conversion switching elements 241 to 244.

The intermediate capacitor 110 is provided between the AC / DC conversion circuit 200 and the second conversion circuit 240. Specifically, the intermediate capacitor 110 is connected to the positive electrode wiring LN1 and the negative electrode wiring LN2.

Here, as described above, the first conversion circuit 230 is connected to the positive electrode wiring LN1 and the negative electrode wiring LN2. Therefore, the intermediate capacitor 110 and the first conversion circuit 230 are connected via the positive electrode wiring LN1 and the negative electrode wiring LN2.

In the present embodiment, as shown in FIG. 6, the intermediate capacitor 110 is provided on the second conversion circuit 240 side of the connection point with the first conversion circuit 230 in the positive electrode wiring LN1 and the negative electrode wiring LN2. However, the present invention is not limited to this, and may be provided on the AC / DC conversion circuit 200 side of the connection point.

The control ECU 120 of the present embodiment controls the AC / DC conversion circuit 200, the first conversion circuit 230 and the second conversion circuit 240, specifically, each switching element 211 to 216, 221 to 224, 231 to 234, 241 to 244. By doing so, the charging mode is controlled.

The switching control by the control ECU 120 of the present embodiment will be described in detail below. For convenience of explanation, in the following description, the mode for charging the vehicle power storage device 21 using only the system power Pa among the system modes is set as the first system mode, and the system power Pa and the power storage for the power supply among the system modes. The mode in which charging is performed using both of the devices 12 is defined as the second system mode.

The control ECU 120 of the present embodiment controls the AC / DC conversion circuit 200 so that the intermediate voltage Vm applied to the intermediate capacitor 110 becomes the first supply-time intermediate voltage Vm1a in the first system mode. Specifically, the control ECU 120 PWMs the primary side switching elements 211 to 216 and the secondary side switching elements 221 to 224 so that the DC power of the first supply intermediate voltage Vm1a is output from the AC / DC conversion circuit 200. Control. As a result, the primary side switching elements 211 to 216 and the secondary side switching elements 221 to 224 are periodically turned ON / OFF to perform AC / DC conversion. That is, the control ECU 120 controls the AC / DC conversion circuit 200 so that the system power Pa is converted into the DC power of the first supply intermediate voltage Vm1a.

Here, the first supply-time intermediate voltage Vm1a is set higher than the power supply voltage Vp and the charging voltage Vr. As described above, in the present embodiment, the power supply voltage Vp and the charging voltage Vr fluctuate, so that the first supply-time intermediate voltage Vm1a of the present embodiment is set higher than the maximum power supply voltage Vpmax and the maximum charging voltage Vrmax. There is.

Specifically, the control ECU 120 calculates the duty ratio of the primary side switching elements 211 to 216 based on the first supply intermediate voltage Vm1a, the turns ratio of the transformer 201, and the like, and the primary side switching element is calculated based on the duty ratio. 211-216 are periodically turned ON / OFF. Further, the control ECU 120 periodically turns ON / OFF the secondary side switching elements 221 to 224 so that the AC power output from the transformer 201 is converted into DC power. The secondary side full bridge circuit 220 can also be said to be a PWM rectifier circuit that rectifies AC power into DC power by PWM control.

According to such a configuration, the DC power of the first supply intermediate voltage Vm1a is output from the AC / DC conversion circuit 200. As a result, electric charges are accumulated in the intermediate capacitor 110 by the DC power of the first supply intermediate voltage Vm1a, and the voltage between the positive electrode wiring LN1 and the negative electrode wiring LN2 is maintained at the first supply intermediate voltage Vm1a by the intermediate capacitor 110. Will be done. That is, the intermediate capacitor 110 functions to stabilize the voltage in the previous stage of the second conversion circuit 240.

When the control ECU 120 is in the first system mode, the second conversion circuit 240 is converted so that the DC power of the first supply intermediate voltage Vm1a output from the AC / DC conversion circuit 200 is converted into the DC power of the charging voltage Vr. To control. In detail, as already described, the first supply-time intermediate voltage Vm1a is set higher than the charging voltage Vr. Therefore, the control ECU 120 performs step-down conversion of DC power by PWM controlling the second conversion switching elements 241 to 244. As a result, the DC power of the charging voltage Vr converted by the second conversion circuit 240 is input to the vehicle power storage device 21, and the vehicle power storage device 21 is charged.

Incidentally, the control ECU 120 stops the first conversion circuit 230 in the first system mode. Specifically, the control ECU 120 keeps the first conversion switching elements 231 to 234 in the OFF state so that the DC power of the first supply intermediate voltage Vm1a is not supplied to the power storage device 12. That is, when the control ECU 120 is in the first system mode, the control ECU 120 does not perform PWM control for the first conversion circuit 230. Therefore, the first conversion switching elements 231 to 234 are not periodically turned ON / OFF.

The control ECU 120 controls the AC / DC conversion circuit 200 so that the intermediate voltage Vm becomes the second supply-time intermediate voltage Vm1b in the second system mode. Specifically, the control ECU 120 controls the AC / DC conversion circuit 200 so that the system power Pa is converted into the DC power of the second supply intermediate voltage Vm1b. This control mode is the same as in the first system mode.

In the second system mode, the control ECU 120 controls the first conversion circuit 230 so that the power of the power storage device 12 is converted into the DC power of the second supply intermediate voltage Vm1b.
Here, the second supply-time intermediate voltage Vm1b is set higher than the power supply voltage Vp and the charging voltage Vr. As described above, in the present embodiment, the power supply voltage Vp and the charging voltage Vr fluctuate, so that the second supply-time intermediate voltage Vm1b of the present embodiment is set higher than the maximum power supply voltage Vpmax and the maximum charging voltage Vrmax. There is. Therefore, the control ECU 120 performs boost conversion of DC power by PWM controlling the first conversion switching elements 231 to 234. The magnitude relationship between the second supply intermediate voltage Vm1b and the first supply intermediate voltage Vm1a is arbitrary, and may be the same or different, for example.

As described above, the second conversion circuit 240 is connected to both the AC / DC conversion circuit 200 and the first conversion circuit 230. Therefore, both the DC power output from the AC / DC conversion circuit 200 and the DC power output from the first conversion circuit 230 are input to the second conversion circuit 240.

When the control ECU 120 is in the second system mode, the DC power of the second supply intermediate voltage Vm1b output from both the AC / DC conversion circuit 200 and the first conversion circuit 230 becomes the DC power of the charging voltage Vr. The second conversion circuit 240 is controlled so as to be converted. As a result, the vehicle power storage device 21 is charged.

In the power supply mode, the control ECU 120 periodically turns on / off the first conversion switching elements 231 to 234 and the second conversion switching elements 241 to 244, thereby using the power storage device 12 to turn on and off the vehicle power storage device 21. Charge.

Specifically, the control ECU 120 controls the first conversion circuit 230 (first conversion switching elements 231 to 234) so that the intermediate voltage Vm is higher than both the power supply voltage Vp and the charging voltage Vr. Then, the control ECU 120 controls the second conversion circuit 240 (second conversion switching elements 241 to 244) so that the DC power of the intermediate voltage Vm is converted into the DC power of the charging voltage Vr.

On the other hand, the control ECU 120 stops the AC / DC conversion circuit 200 in the power supply mode. Specifically, the control ECU 120 has at least one of the primary side switching elements 211 to 216 and the secondary side switching elements 221 to 224 so that the power output from the first conversion circuit 230 does not return to the system power supply 11 (this implementation). In the form, both) are maintained in the OFF state. That is, the control ECU 120 does not perform PWM control on the AC / DC conversion circuit 200 in the power supply mode. Therefore, the primary side switching elements 211 to 216 and the secondary side switching elements 221 to 224 are not periodically turned ON / OFF.

According to the present embodiment described in detail above, the following effects are exhibited in place of (1-6).
(3-1) The charging device 30 includes an AC / DC conversion circuit 200, a first conversion circuit 230, a second conversion circuit 240, and an intermediate capacitor 110. The AC / DC conversion circuit 200 converts the system power Pa output from the system power supply 11 into DC power. The first conversion circuit 230 is a power conversion circuit connected to the power storage device 12, and includes first conversion switching elements 231 to 234. The second conversion circuit 240 is a power conversion circuit connected to both the AC / DC conversion circuit 200 and the first conversion circuit 230, and has the second conversion switching elements 241 to 244. The charging device 30 outputs the DC power converted by the second conversion circuit 240 toward the vehicle power storage device 21. The control ECU 120 controls the charging mode by controlling the AC / DC conversion circuit 200, the first conversion switching elements 231 to 234 of the first conversion circuit 230, and the second conversion switching elements 241 to 244 of the second conversion circuit 240. ..

According to such a configuration, by controlling the AC / DC conversion circuit 200 and both conversion switching elements 231 to 234 and 241 to 244, the vehicle power storage device 21 can be charged while controlling the charging mode.

As an example, the control ECU 120 controls the AC / DC conversion circuit 200 so that the system power Pa output from the system power supply 11 is converted into DC power. Then, the control ECU 120 periodically turns on / off the second conversion switching elements 241 to 244 so that the DC power output from the AC / DC conversion circuit 200 is step-down converted and output to the vehicle power storage device 21. Let me. As a result, the charging mode becomes the first system mode.

Further, the control ECU 120 controls the AC / DC conversion circuit 200 so that the system power Pa output from the system power supply 11 is converted into DC power, and the first conversion switching elements 231 to 234 are periodically turned ON / OFF. By doing so, the DC power of the power storage device 12 is boosted and converted. Then, the control ECU 120 performs a second conversion so that the DC power output from the AC / DC conversion circuit 200 and the DC power output from the first conversion circuit 230 are step-down converted and output to the vehicle power storage device 21. The switching elements 241 to 244 are periodically turned ON / OFF. As a result, the charging mode becomes the second system mode.

Then, the control ECU 120 periodically turns on / off the first conversion switching elements 231 to 234 so that the DC power of the power storage device 12 is boosted and converted, and the DC power output from the first conversion circuit 230 is generated. The second conversion switching elements 241 to 244 are periodically turned ON / OFF so as to be step-down converted and output to the vehicle power storage device 21. As a result, the charging mode becomes the power supply mode.

In addition, each of the above-mentioned embodiments may be changed as follows. Further, as long as there is no technical contradiction, each of the above embodiments and the following alternative examples may be appropriately combined.
○ The control ECU 120 may directly compare the target SOCXa and the system target threshold value Xat1 without going through the required power Prq, and set the charging mode based on the comparison result. For example, the control ECU 120 compares the target SOCXa with the system target threshold value Xat1, and if the target SOCXa is equal to or less than the system target threshold value Xat1, sets the charging mode to the second system mode, and the target SOCXa is from the system target threshold value Xat1. If the value is high, the charging mode may be set to the first system mode.

○ The system target threshold value Xat1 is not limited to the target SOCXa in which the required power Prq is the system maximum power Pamax, and is arbitrary. For example, the system target threshold value Xat1 may be a constant fixed value regardless of the system maximum power Pamax.

○ The power supply target threshold value Xat2 is not limited to the target SOCXa in which the required power Prq is the power supply maximum power Pbmax, and is arbitrary. For example, the power supply target threshold value Xat2 may be a variable value that changes according to the target SOCXa or the power supply SOCXb, or may be a constant fixed value regardless of the target SOCXa and the power supply SOCXb.

○ The system target threshold value Xat1 and the power supply target threshold value Xat2 may be different or the same.
○ The power threshold value Xbt may be a constant fixed value regardless of the target SOCXa. In this case, the power supply threshold value Xbt may be "0" or other than "0".

○ The vehicle ECU 22 may be configured to grasp the required power Prq corresponding to the current target SOCXa. In this case, the vehicle ECU 22 may transmit information regarding the required power Prq to the control ECU 120. Then, in step S101, the control ECU 120 may be configured to grasp the required power Prq by receiving information about the required power Prq from the vehicle ECU 22.

○ When the charging mode is the second system mode, the control ECU 120 may follow the change of the required power Prq by changing the system power Pa, or may change both the system power Pa and the power supply power Pb. It may follow the change of the required power Prq. That is, it is not essential to maintain the system maximum power Pamax in the second system mode.

○ The primary side circuit 80 may be AC / AC converted, and its specific configuration is not limited to that of the embodiment and is arbitrary.
○ The booster circuit 90 is configured to be capable of converting AC power output (in other words, transmitted) from the first transformer 60 into DC power and boosting the power output from the power storage device 12. The specific configuration is arbitrary.

○ The step-down circuit 100 only needs to be able to step down the DC power output from the step-up circuit 90 via the intermediate capacitor 110, and its specific configuration is arbitrary.
○ The specific circuit configuration of the AC / DC conversion circuit 200 is not limited to that of the third embodiment and is arbitrary. For example, the AC / DC conversion circuit 200 is not limited to a configuration capable of bidirectional conversion of AC power, and may be a one-way conversion circuit that converts system power Pa into DC power. As an example, the AC / DC conversion circuit 200 may be a rectifier circuit having a diode bridge instead of the primary side matrix converter 210 and the transformer 201. Further, the AC / DC conversion circuit 200 may have a configuration having a half bridge circuit or a diode bridge circuit instead of the secondary side full bridge circuit 220. In short, the AC / DC conversion circuit 200 may convert the system power Pa into DC power having a desired voltage.

○ The specific circuit configuration of the first conversion circuit 230 is arbitrary as long as the power of the power storage device 12 can be converted into voltage. For example, the first conversion circuit 230 may have a configuration having a half-bridge circuit. Further, the first conversion circuit 230 is not limited to the bidirectional converter, and may be configured to perform only one-way voltage conversion.

○ The specific circuit configuration of the second conversion circuit 240 is arbitrary as long as the DC power input from the AC / DC conversion circuit 200 or the first conversion circuit 230 can be voltage-converted. Further, the second conversion circuit 240 can voltage-convert the DC power input from the AC / DC conversion circuit 200 or the first conversion circuit 230, but cannot voltage-convert the power of the vehicle power storage device 21. It may be a circuit. That is, the second conversion circuit 240 may be configured to perform only one-way voltage conversion.

○ The number of power storage devices is arbitrary, and may be two or more. That is, the power storage device includes both one case and a plurality of cases. In this case, the power system 10 may be configured to supply power to the vehicle power storage device 21 by using a part of the power power storage devices and the system power supply 11 among the plurality of power supply power storage devices, or the power supply system 10 may be configured to supply power to the vehicle power storage device 21. The power storage device 21 may be supplied with electric power by using all the power storage devices and the system power supply 11. That is, when the power system 10 has a plurality of power storage devices, the system mode is a mode in which charging is performed using the system power source 11 or at least one of the system power source 11 and the plurality of power storage devices. It should be.

○ Either one of the first system mode and the second system mode may be omitted.
○ The power mode may be omitted.
○ The power storage device 12 may be a part of the charging device 30. That is, the charging device 30 may or may not include the power storage device 12.

Next, a suitable example that can be grasped from the above embodiment and another example will be described below.
(B) The power supply threshold value may be set so as to increase as the target SOC decreases.

10 ... Power system, 11 ... System power supply, 12 ... Power storage device, 20 ... Vehicle, 21 ... Vehicle power storage device, 30 ... Charging device, 31-33 ... System input terminal, 34, 35 ... Power storage input terminal, 40 ... Connector, 41, 42 ... Load input terminal, 43 ... Control terminal, 50 ... Filter circuit, 60 ... First transformer, 61 ... First primary winding, 62 ... First secondary winding, 62a ... 1st intermediate tap, 70 ... 2nd transformer, 71 ... 2nd primary winding, 72 ... 2nd secondary winding, 72a ... 2nd intermediate tap, 80 ... 1st circuit, 82ua ~ 82wb ... primary side switching element, 90 ... step-up circuit (first secondary side circuit), 92-95 ... step-up switching element, 100 ... step-down circuit (second secondary side circuit), 102-105 ... step-down switching Element, 110 ... Intermediate capacitor, 120 ... Control ECU, 121 ... Power supply voltage sensor, 122 ... Charging voltage sensor, 200 ... AC / DC conversion circuit, 230 ... First conversion circuit, 231 to 234 ... First conversion switching element, 240 ... second conversion circuit, 241 to 244 ... second conversion switching element, Pa ... system power, Pamax ... system maximum power, Pat ... system target power, Pb ... power supply power, Pbmax ... power supply maximum power, Pbt ... power supply target power, Xa ... target SOC, Xa1 ... first target value, Xa2 ... second target value, Xat1 ... system target threshold, Xat2 ... power target threshold, Xb ... power SOC, Xbt ... power threshold, Prq ... required power (suitable for charging) Power), Prq1 ... 1st power, Prq2 ... 2nd power, Vm ... Intermediate voltage.

Claims (10)

A power system that charges a target power storage device using at least one of a grid power supply and a power storage device.
As the charging mode for charging the target power storage device, a first system mode using the system power supply, a second system mode using both the system power supply and the power storage device, and a power supply mode using the power power storage device. And, with a charging device,
A control unit that controls the charging mode based on the target SOC, which is the SOC of the target power storage device, and the power supply SOC, which is the SOC of the power storage device.
Equipped with
The control unit is a power system characterized in that the charging mode is switched according to a change in the target SOC while the target power storage device is being charged. When the target SOC is lower than the predetermined system target threshold value and the power supply SOC is equal to or higher than the predetermined power supply threshold value, the control unit sets the charging mode to the second system mode, and the control unit sets the charging mode to the second system mode. The power system according to claim 1, wherein when the target SOC is equal to or higher than the system target threshold value, the charging mode is set to the first system mode. The power system according to claim 2, wherein the control unit sets the charging mode to the first system mode when the target SOC is lower than the system target threshold and the power supply SOC is lower than the power supply threshold. .. The electric power suitable for charging the target power storage device is
When the target SOC is equal to or less than a predetermined first target value, it is the first power, and when the target SOC is equal to or higher than the second target value higher than the first target value, the second power is used. Yes, it decreases from the first target value toward the second target value.
The system maximum power, which is the maximum power that the system power supply can output, is higher than the first power and lower than the second power.
The power system according to claim 2 or 3, wherein the system target threshold value is the target SOC in which the power suitable for charging the target power storage device is the system maximum power. When the charging mode is the second system mode, the control unit is used for the power source while maintaining the system power output from the system power supply at the system maximum power in response to a change in the target SOC. The power system according to claim 4, wherein the power supply power output from the power storage device is variably controlled. The control unit sets the charging mode to the second system mode when the target SOC is lower than the predetermined power target threshold in a situation where the power SOC is equal to or higher than the predetermined power threshold. On the other hand, the power system according to claim 1, wherein the charging mode is set to the power supply mode when the target SOC is equal to or higher than the power supply target threshold value in a situation where the power supply SOC is equal to or higher than the power supply threshold value. The electric power suitable for charging the target power storage device is
When the target SOC is equal to or less than a predetermined first target value, it is the first power, and when the target SOC is equal to or higher than the second target value higher than the first target value, the second power is used. Yes, it decreases from the first target value toward the second target value.
The maximum power source, which is the maximum power that can be output by the power storage device, is higher than the first power and lower than the second power.
The power system according to claim 6, wherein the power supply target threshold value is the target SOC in which the power suitable for charging the target power storage device is the power supply maximum power. The charging device is
A first transformer having a first primary winding and a first secondary winding having a first intermediate tap to which the power storage device is connected.
It comprises a second primary winding connected in series with the first primary winding and a second secondary winding having a second intermediate tap to which the target power storage device is connected. With the second transformer
A power conversion circuit connected to the system power supply and connected to a series connection of the first primary winding and the first secondary winding, and has a primary switching element 1. Next side circuit and
A power conversion circuit connected to the power storage device, the first secondary coil provided between the first intermediate tap and the power storage device, and the first secondary side winding. A first secondary circuit having a first secondary switching element connected to a wire, and
A power conversion circuit provided between the first secondary side circuit and the target power storage device, and a second secondary coil provided between the second intermediate tap and the target power storage device. A second secondary circuit having a second secondary switching element connected to the second secondary winding.
An intermediate capacitor provided between the first secondary circuit and the second secondary circuit,
Equipped with
Of claims 1 to 7, the control unit controls the charging mode by controlling the primary side switching element, the first secondary side switching element, and the second secondary side switching element. The power system according to any one. The charging device is
An AC / DC conversion circuit that converts the system power output from the system power supply into DC power,
A power conversion circuit connected to the power storage device, the first conversion circuit having the first conversion switching element, and the first conversion circuit.
A power conversion circuit connected to both the AC / DC conversion circuit and the first conversion circuit, the second conversion circuit having the second conversion switching element, and the second conversion circuit.
An intermediate capacitor provided between the AC / DC conversion circuit and the second conversion circuit and connected to the first conversion circuit, and
The DC power converted by the second conversion circuit is output to the target power storage device.
The control unit according to any one of claims 1 to 7, wherein the control unit controls the charging mode by controlling the AC / DC conversion circuit, the first conversion switching element, and the second conversion switching element. Power system. It is used to charge the target power storage device using at least one of the system power supply and the power storage device, and as a charging mode for charging the target power storage device, a first system mode using the system power supply and a first system mode using the system power supply. A charging device having a second system mode in which both the system power supply and the power storage device are used, and a power supply mode in which the power power storage device is used.
A control unit that controls the charging mode based on the target SOC, which is the SOC of the target power storage device, and the power supply SOC, which is the SOC of the power storage device, is provided.
The control unit is a charging device characterized in that the charging mode is switched according to a change in the target SOC while the target power storage device is being charged.

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