JP2022162723A - Power supply device - Google Patents

Abstract

To suppress an unintended power transmission caused by low intermediate voltage.SOLUTION: A power supply device 10 has an AC/DC converter 20, a DC/DC converter 30 for load, an intermediate capacitor 40, a power storage unit 50, and a control circuit 60. The power storage unit 50 has a power storage device 51, a DC/DC converter 53 for power storage, a switch 54, and a resistor 55 connected in parallel with the switch 54. When power supply to an object power storage device 120 is performed by using the power storage device 51 in a state where input voltage to the AC/DC converter 20 from an AC power supply 110 is equal to or less than determination voltage, the control circuit 60 performs charging to the intermediate capacitor 40 by operating the DC/DC converter 53 for power storage in a state where the switch 54 is turned OFF.SELECTED DRAWING: Figure 1

Description

The present invention relates to a power supply device.

A power supply device that converts AC power output from an AC power supply into DC power and supplies the DC power to a load is known (for example, Patent Document 1). The power supply device described in Patent Document 1 includes an AC/DC converter that converts AC power from an AC power supply into DC power, and a load DC/DC that converts the DC power output by the AC/DC converter and supplies it to a load. It comprises a converter, an intermediate capacitor provided between the AC/DC converter and the load DC/DC converter, and a control circuit for controlling the load DC/DC converter.

JP 2018-102117 A

In such a power supply device, when power transmission to a load is started in a state where the intermediate voltage applied to the intermediate capacitor is low, power may be transmitted through an unintended path. In this case, there is a concern that the power conversion efficiency will decrease and excessive current will flow.

A power supply device that solves the above problems includes an AC/DC converter that converts AC power input from an AC power supply into DC power, and a load DC that converts the DC power output from the AC/DC converter and supplies it to a load. /DC converter, an intermediate capacitor provided between the AC/DC converter and the load DC/DC converter, and a capacitor connected to the intermediate capacitor and connected in parallel to the load DC/DC converter. and a control circuit that controls the load DC/DC converter and the one or more power storage units, wherein the one or more power storage units include a power storage device and the power storage unit. a power storage DC/DC converter that converts the power of a device and outputs the power to the intermediate capacitor; a switch provided between the power storage device and the power storage DC/DC converter; and a parallel connection with the switch. and a resistor, wherein the control circuit supplies power to the load using the power storage device in a situation where the input voltage from the AC power supply to the AC/DC converter is equal to or lower than the judgment voltage. and charging the intermediate capacitor by operating the power storage DC/DC converter with the switch in the OFF state so that the intermediate voltage, which is the voltage of the intermediate capacitor, is equal to or higher than the voltage of the power storage device. It is equipped with a pre-charging unit that performs

According to such a configuration, since the power storage unit is connected in parallel to the load DC/DC converter, for example, even when there is no power supply from the AC power supply and the input voltage from the AC power supply is equal to or lower than the judgment voltage. By operating the power storage DC/DC converter and the load DC/DC converter, power can be supplied to the load using the power storage device of the power storage unit.

Here, when the input voltage is equal to or lower than the determination voltage, the intermediate voltage may become lower than the voltage of the power storage device. In this case, unintended power transmission may occur. On the other hand, if the power storage device and the intermediate capacitor are connected in a state where the intermediate capacitor is not charged, an excessive current may flow.

In this respect, according to this configuration, by operating the power storage DC/DC converter with the switch in the OFF state, power is transmitted from the power storage device to the intermediate capacitor via the resistor, and the intermediate voltage is transferred to the power storage device. above the voltage of As a result, the intermediate voltage can be equal to or higher than the voltage of the power storage device while suppressing excessive current flow. Therefore, subsequent power supply to the load using the power storage device can be performed favorably.

The power supply device includes a plurality of power storage units, each of the plurality of power storage units includes the power storage device, and the pre-charging unit has the intermediate voltage higher than the maximum voltage of the plurality of power storage devices. The power storage DC/DC converter may be operated while the switch is in an OFF state so as to increase the voltage.

According to such a configuration, the intermediate voltage is boosted to a voltage higher than the maximum value of the voltages of the plurality of power storage devices, so power transmission from one power storage device to another power storage device is suppressed, for example. Therefore, it is possible to suppress a decrease in the efficiency of power supply to the load due to unintended power transmission.

With respect to the power supply device, the control circuit determines in advance the SOC of the power storage device among the one or more power storage units in a situation where the input voltage from the AC power supply to the AC/DC converter is equal to or lower than a judgment voltage. a permissible power storage unit that determines whether or not there is an allowable power storage unit having an allowable power storage device having a discharge permissible value or more; The pre-charging unit turns off the switch of the allowable power storage unit so that the intermediate voltage becomes equal to or higher than the voltage of the allowable power storage unit. The power storage DC/DC converter of the allowable power storage unit may be operated in a state where the power storage unit is in a state where

According to such a configuration, power is supplied to the load using the power storage device having an SOC equal to or higher than the discharge allowable value. This makes it possible to suppress deterioration of the power storage device caused by supplying power to the load using the power storage device with a low SOC. Therefore, it is possible to extend the life of the power supply device.

In the above power supply device, when there are a plurality of allowable power storage devices, the control circuit may supply power to the load using one of the plurality of allowable power storage devices having the highest SOH. .

According to this configuration, power is supplied to the load using the allowable power storage device that is relatively undegraded. As a result, the frequency of power supply to the load using the relatively deteriorated power storage device is reduced, so that progress of deterioration of the power storage device can be suppressed. Therefore, excessive deterioration of a specific power storage device can be suppressed.

With respect to the power supply device, the control circuit is adapted to supply power from at least one of the power storage devices to the load via the switch after the intermediate capacitor is charged by the precharging unit. , the load DC/DC converter and the power storage DC/DC converter may be operated while the switch is in an ON state.

According to such a configuration, when power is supplied to the load, the power of the power storage device is supplied to the load via the switch having a smaller loss than the resistance. As a result, power consumption by the resistance can be suppressed when power is supplied to the load. Therefore, it is possible to suppress a decrease in the power conversion efficiency of the power supply device.

In the power supply device, the load is a chargeable target power storage device, and the pre-charging unit performs the power storage when the input voltage from the AC power supply to the AC/DC converter is equal to or lower than the determination voltage. When the device is used to charge the target power storage device, the power storage DC/DC converter is operated with the switch turned off so that the intermediate voltage becomes higher than the voltage of the target power storage device. , may be

According to such a configuration, the target power storage device can be charged by the step-down conversion performed by the load DC/DC converter. In addition, reverse electric power flow from the target power storage device to the power storage device can be suppressed.

According to the present invention, unintended power transmission due to low intermediate voltage can be suppressed.

1 is an overall schematic diagram of a power system to which a power supply device is applied; FIG. FIG. 5 is a diagram showing an example of power supply processing;

<About the power supply system>
An embodiment of a power supply device and a power supply system including the power supply device will be described below.

As shown in FIG. 1 , the power supply system 100 includes an AC power supply 110 that outputs AC power, a target power storage device 120 as a load to which DC power is supplied, and a power supply device 10 .
AC power supply 110 is a power source that outputs AC power. Any AC power source can be used as the AC power source 110, and for example, it is a three-phase AC power source such as a system power source. The maximum value of AC power that can be supplied by the AC power supply 110 varies, for example, depending on the content of the contract with the power company or the power usage status of other power systems.

The target power storage device 120 of the present embodiment is rechargeable, and an example is a secondary battery. A secondary battery is, for example, a lithium ion storage battery or a lead storage battery. The target power storage device 120 may be, for example, one mounted on a vehicle.

The target power storage device 120 may be provided with the target BMS 121 . The target BMS 121 is a battery management system (BMS) that monitors the required power Pr, voltage Vr, SOC (state of charge), and SOH (state of health) of the target power storage device 120. be. The required power Pr of the target power storage device 120 is the power required to charge the target power storage device 120 . For convenience of explanation, voltage Vr of target power storage device 120 is referred to as target voltage Vr in the following description.

Power supply device 10 is provided between AC power supply 110 and target power storage device 120 . The AC power of the AC power supply 110 can be converted into DC power and supplied to the target power storage device 120 .
The power supply device 10 includes an AC/DC converter 20, a load DC/DC converter 30, a load switch 31, a load resistor 32, an intermediate capacitor 40, an intermediate voltage sensor 41, a plurality of power storage units 50, a control and a circuit 60 .

AC/DC converter 20 is connectable to AC power supply 110 . AC/DC converter 20 converts AC power from AC power supply 110 into DC power. Although the AC/DC converter 20 may take any specific form, for example, it is a DAB (Dual Active Bridge) type AC/DC converter. A DAB AC/DC converter can control an output voltage by controlling a phase difference and a duty ratio of a secondary side circuit that outputs DC power.

The load DC/DC converter 30 is connected to the AC/DC converter 20 . Load DC/DC converter 30 converts the DC power output from AC/DC converter 20 and supplies it to target power storage device 120 . The load DC/DC converter 30 of this embodiment is a chopper circuit. Note that the load DC/DC converter 30 may have any specific form, and may be, for example, a SEPIC converter or an LLC converter.

Intermediate capacitor 40 is provided between AC/DC converter 20 and load DC/DC converter 30 .
Intermediate voltage sensor 41 is a voltage sensor that measures intermediate voltage Vm, which is the voltage of intermediate capacitor 40 .

A plurality of power storage units 50 are each connected to intermediate capacitor 40 and connected in parallel to load DC/DC converter 30 . The power storage unit 50 is a power unit capable of outputting DC power to the load DC/DC converter 30 and the intermediate capacitor 40 . Each of the plurality of power storage units 50 includes a power storage device 51 , a power storage DC/DC converter 53 , a switch 54 and a resistor 55 .

The power storage device 51 is a power source capable of outputting DC power, and is, for example, a secondary battery. Each power storage device 51 includes a power storage BMS 52 . Each power storage BMS 52 monitors the voltage Vdc, SOC, and SOH of each power storage device 51 .

The power storage DC/DC converter 53 can step-down convert the DC voltage output from the AC/DC converter 20 and output it to the power storage device 51 . Thereby, the power storage DC/DC converter 53 can charge the power storage device 51 using the AC power of the AC power supply 110 . Further, the power storage DC/DC converter 53 can boost and convert the power of the power storage device 51 and output it toward the load DC/DC converter 30 and the intermediate capacitor 40 . The power storage DC/DC converter 53 operates by operating a switching element provided in the power storage DC/DC converter 53 . Although the DC/DC converter 53 for power storage may take any specific form, it is, for example, a chopper circuit like the DC/DC converter 30 for load.

Switch 54 is provided between power storage device 51 and power storage DC/DC converter 53 . Although the switch 54 of this embodiment is a relay switch, any form such as MOSFET or IGBT can be adopted.

A resistor 55 is connected in parallel with the switch 54 . When the switch 54 is in the ON state, the electric power of the power storage device 51 is supplied to the power storage DC/DC converter 53 via the switch 54 . When the switch 54 is in the OFF state, the power of the power storage device 51 is supplied to the power storage DC/DC converter 53 via the resistor 55 .

The control circuit 60 controls the AC/DC converter 20, the load DC/DC converter 30, the load switch 31, and each power storage unit 50 (more specifically, the power storage DC/DC converter 53 and the switch 54). A specific hardware configuration of the control circuit 60 is arbitrary. For example, the control circuit 60 may be configured to have a dedicated hardware circuit for performing switching control, or may include a memory storing a control program for performing switching control and necessary information, and switching control based on the control program. A configuration having a CPU that performs

The control circuit 60 is configured to be able to acquire information for controlling each member. Specifically, the control circuit 60 receives the input voltage Vac from the AC/DC converter 20, the required power Pr, the target voltage Vr, SOC, and SOH of the target power storage device 120 from the target BMS 121, and the target voltage Vr, SOC, and SOH from each power storage BMS 52 to each power storage device. 51 voltages Vdc, SOC, and SOH can be obtained. Any method can be used to acquire this information, but for example, communication according to vehicle communication protocols such as CAN: Controller Area Network and LIN: Local Interconnect Network can be mentioned.

The control circuit 60 executes a power supply process of supplying power to the target power storage device 120 using at least one of the AC power supply 110 and the power storage device 51 of the power storage unit 50 by controlling each member described above.

<About power supply processing>
An example of power supply processing performed by the control circuit 60 will be described below. The power supply process in this embodiment is a process of supplying power to the target power storage device 120 . Power supply to the target power storage device 120 is charging the target power storage device 120, for example. In the following description, it is assumed that the load switch 31 and each switch 54 are in the OFF state when the power supply process is started.

As shown in FIG. 2, control circuit 60 acquires input voltage Vac from AC/DC converter 20 in step S1.
Next, in step S2, the control circuit 60 determines whether or not the input voltage Vac is equal to or lower than the determination voltage V1. Although the determination voltage V1 can be set arbitrarily, it is, for example, equal to or higher than the lower limit of the voltage at which the AC power supply 110 operates normally.

First, the processing of the control circuit 60 when the determination result in step S2 is negative will be described. If the determination result in step S2 is negative, that is, if the input voltage Vac is higher than the determination voltage V1, this corresponds to, for example, a situation where the AC power supply 110 is operating normally.

In this case, the control circuit 60 proceeds to step S10 to acquire the target voltage Vr from the target BMS 121 and the voltage Vdc of each power storage device 51 from the power storage BMS 52 of each power storage device 51, respectively.

Next, the control circuit 60 proceeds to step S<b>11 to specify the maximum value Vmax from the target voltage Vr and the voltage Vdc of each power storage device 51 acquired in step S<b>10 . The maximum value Vmax is the maximum voltage among the target voltage Vr and the voltages Vdc of the plurality of power storage devices 51 .

Next, the control circuit 60 proceeds to step S12 to set the target intermediate voltage Vt. The target intermediate voltage Vt is a value higher than the maximum value Vmax specified in step S11. The target intermediate voltage Vt in this embodiment is a value higher than the maximum value Vmax specified in step S11 by a predetermined value. The predetermined value may be appropriately set based on power conversion efficiency or the like.

Next, the control circuit 60 proceeds to step S13 and uses the AC/DC converter 20 to charge the intermediate capacitor 40 so that the intermediate voltage Vm becomes the target intermediate voltage Vt. At this time, the control circuit 60 acquires the intermediate voltage Vm from the intermediate voltage sensor 41 . When the AC/DC converter 20 is a DAB type AC/DC converter, the output voltage of the AC/DC converter 20 is controlled by controlling the phase difference and duty ratio of the secondary side circuit of the AC/DC converter 20. Therefore, the intermediate capacitor 40 should be charged. A specific control mode of the AC/DC converter 20 is arbitrary.

Next, the control circuit 60 proceeds to step S14 and determines whether or not the intermediate voltage Vm acquired in step S13 matches the target intermediate voltage Vt. The state in which two values match includes not only the state of complete match but also the state in which the difference between the two values is equal to or less than a predetermined value. The predetermined value may be appropriately set based on the measurement error or the like.

If the determination result in step S14 is negative, the control circuit 60 returns to step S13 to continue charging the intermediate capacitor 40. FIG.
On the other hand, if the determination result in step S14 is affirmative, the control circuit 60 proceeds to step S15 and switches the load switch 31 from the OFF state to the ON state. After that, the control circuit 60 proceeds to step S16.

In step S<b>16 , control circuit 60 starts power supply to target power storage device 120 using AC power supply 110 by operating AC/DC converter 20 and load DC/DC converter 30 . Specifically, the control circuit 60 controls the AC/DC converter 20 so that the intermediate voltage Vm becomes the target intermediate voltage Vt, and controls the load DC/DC converter 30 so that a current corresponding to the required power Pr flows. to control.

Here, since the target intermediate voltage Vt is set higher than the target voltage Vr, the intermediate voltage Vm is higher than the target voltage Vr. Therefore, step-down conversion is performed in the load DC/DC converter 30 . In other words, it can be said that the load DC/DC converter 30 performs step-down conversion so that a current corresponding to the required power Pr flows.

Incidentally, when the required power Pr is less than the predetermined threshold, the control circuit 60 supplies power using only the AC power supply 110 as described above. may supply power using either the AC power supply 110 or each power storage device 51 . In this case, the control circuit 60 selects one or more effective power storage devices 51 b among the power storage devices 51 . The effective power storage device 51 b is the power storage device 51 used to supply power to the target power storage device 120 . A mode of selecting the effective power storage device 51b will be described later.

In the following description, the effective power storage unit 50b includes the effective power storage device 51b, and the power storage DC/DC converter 53, the switch 54, and the resistor 55 provided in the effective power storage unit 50b are respectively referred to as the effective power storage DC/DC They may be referred to as converter 53b, run switch 54b, and run resistor 55b.

Then, the control circuit 60 switches the execution switch 54b from the OFF state to the ON state so that power is supplied to the target power storage device 120 from both the effective power storage device 51b and the target power storage device 120, and switches the execution switch 54b from the OFF state to the ON state. The DC/DC converter 53b is operated.

Here, since the target intermediate voltage Vt is set higher than the voltage Vdc of each power storage device 51, the intermediate voltage Vm is higher than the voltage Vdc of the effective power storage device 51b. Therefore, the control circuit 60 controls the load DC/DC converter 30 and the load DC/DC converter 30 so that the effective power storage DC/DC converter 53b performs step-up conversion and the load DC/DC converter 30 performs step-down conversion. The effective power storage DC/DC converter 53b is operated.

Next, the processing of the control circuit 60 when the determination result in step S2 is affirmative will be described. If the determination result in step S2 is affirmative, it means that the input voltage Vac from the AC power supply 110 to the AC/DC converter 20 is equal to or lower than the determination voltage V1, and corresponds to power failure, for example.

In this case, the control circuit 60 proceeds to step S20 to acquire the target voltage Vr from the target BMS 121 and the voltages Vdc, SOC, and SOH of each power storage device 51 from each power storage BMS 52, respectively.

Next, the control circuit 60 proceeds to step S21 and determines whether or not there is an allowable power storage unit 50a by comparing the SOC of each power storage device 51 acquired in step S20 with the discharge allowable value SOC1. The allowable power storage unit 50a is the power storage unit 50 having the allowable power storage device 51a. The allowable power storage device 51a is the power storage device 51 whose SOC is equal to or higher than a predetermined discharge allowable value SOC1. Note that the allowable discharge value SOC1 can be set to any value, but is, for example, the lower limit value of SOC at which charging from each power storage device 51 to the intermediate capacitor 40 is allowed. In this embodiment, the control circuit 60 that executes the process of step S21 corresponds to the allowable determination unit.

If the determination result in step S21 is negative, that is, if it is determined that there is no allowable power storage unit 50a, the control circuit 60 ends the power supply process without supplying power to the target power storage device 120. FIG. At this time, the control circuit 60 may notify the outside that it has been determined that there is no allowable power storage unit 50a.

On the other hand, if the determination result in step S21 is affirmative, that is, if it is determined that there are allowable power storage units 50a, the control circuit 60 proceeds to step S22 and determines whether or not there are a plurality of allowable power storage units 50a. If the determination result of step S22 is negative, the control circuit 60 proceeds to step S24. On the other hand, if the determination result of step S22 is affirmative, the control circuit 60 proceeds to step S23.

In step S23, the control circuit 60 selects the execution power storage device 51b by comparing the SOH of each allowable power storage device 51a acquired in step S20, and proceeds to step S24. Specifically, the control circuit 60 selects the one with the highest SOH among the plurality of allowable power storage devices 51a as the effective power storage device 51b. If the determination result in step S22 is negative, that is, if there is only one allowable power storage unit 50a, the control circuit 60 may treat the allowable power storage device 51a included in the allowable power storage unit 50a as the effective power storage device 51b.

In step S24, the control circuit 60 specifies the maximum value Vmax from among the voltage Vdc of each power storage device 51 and the target voltage Vr acquired in step S20.
Next, the control circuit 60 proceeds to step S25 to set the target intermediate voltage Vt. The target intermediate voltage Vt is a value higher than the maximum value Vmax identified in step S23. The target intermediate voltage Vt in this embodiment is a value higher than the maximum value Vmax specified in step S23 by a predetermined value. The predetermined value may be appropriately set based on power conversion efficiency or the like.

Next, the control circuit 60 advances to step S26 to charge the intermediate capacitor 40 from the effective power storage device 51b. In this embodiment, the control circuit 60 operates the effective power storage DC/DC converter 53b so that the intermediate voltage Vm becomes the target intermediate voltage Vt.

Although the specific aspect of the operation of the effective power storage DC/DC converter 53b is arbitrary, for example, by controlling the step-up rate of the effective power storage DC/DC converter 53b, the voltage from the effective power storage DC/DC converter 53b to the intermediate capacitor 40 controls the voltage output to The boost rate is controlled, for example, by controlling the duty ratio of the effective power storage DC/DC converter 53b.

As described above, since the execution switch 54b is in the OFF state, the DC power of the execution power storage device 51b is supplied to the execution power storage DC/DC converter 53b via the execution resistance 55b. Effective power storage DC/DC converter 53 b converts the DC power supplied from effective power storage device 51 b and outputs the converted power to intermediate capacitor 40 . Therefore, the control circuit 60 operates the storage DC/DC converter 53 with the switch 54 in the OFF state by executing the process of step S26. Therefore, in this embodiment, the control circuit 60 that executes the process of step S26 corresponds to the pre-charging section.

Since the target intermediate voltage Vt is higher than the voltage Vdc of the power storage device 51 (specifically, the allowable power storage device 51a), the control circuit 60 operates as a pre-charging unit so that the intermediate voltage Vm reaches the power storage device 51 (specifically, the allowable power storage device 51a). It can be said that the allowable power storage DC/DC converter 53a is operated so that the voltage becomes equal to or higher than the voltage Vdc of 51a).

Similarly, since the target intermediate voltage Vt is higher than the target voltage Vr, the control circuit 60 turns off the allowable switch 54a of the allowable power storage unit 50a so that the intermediate voltage Vm becomes higher than the target voltage Vr. It can be said that the power storage DC/DC converter 53 (more specifically, the allowable power storage DC/DC converter 53a) is operated in this state.

Next, the control circuit 60 proceeds to step S27 and determines whether or not the intermediate voltage Vm acquired in step S26 matches the target intermediate voltage Vt. If the determination result in step S27 is negative, the control circuit 60 returns to step S26 and continues charging the intermediate capacitor 40 with the execution switch 54b turned off. That is, the termination condition of the pre-charging of the intermediate capacitor 40 using the effective power storage DC/DC converter 53b is that the intermediate voltage Vm reaches the target intermediate voltage Vt.

On the other hand, if the determination result in step S27 is affirmative, the control circuit 60 proceeds to step S28 and switches the load switch 31 and the execution switch 54b from OFF to ON.

Next, the control circuit 60 proceeds to step S29, and starts power supply to the target power storage device 120 using the power storage device 51 (more specifically, the effective power storage device 51b). The control circuit 60 operates the load DC/DC converter 30 and the storage DC/DC converter 53 with the execution switch 54b turned on. As a result, power is supplied from the execution power storage device 51b to the target power storage device 120 via the execution switch 54b after the intermediate capacitor 40 is charged by the control circuit 60 as the pre-charging unit. In particular, when there are a plurality of allowable power storage devices 51a, the control circuit 60 supplies power to the target power storage device 120 from the effective power storage device 51b having the highest SOH among the plurality of allowable power storage devices 51a.

Incidentally, when power is supplied to the target power storage device 120 using the effective power storage device 51b, the control circuit 60 performs step-up conversion in the effective power storage DC/DC converter 53b, and the load DC/DC converter The load DC/DC converter 30 and the effective power storage DC/DC converter 53b are operated so that step-down conversion is performed at 30 . In this case, for example, the control circuit 60 may control the duty ratio of the switching element of the effective power storage DC/DC converter 53b so that the intermediate voltage Vm becomes the target intermediate voltage Vt. Then, control circuit 60 may control the duty ratio of the switching element of load DC/DC converter 30 so that a current corresponding to required power Pr is output to target power storage device 120 .

<Action>
Next, the operation of this embodiment will be described.
For example, when there is no power supply from the AC power supply 110, it is determined in step S1 that the input voltage Vac is equal to or lower than the determination voltage V1. At this time, the control circuit 60 operates the power storage DC/DC converter 53 before power is supplied from the power storage device 51 to the target power storage device 120 so that the intermediate voltage Vm becomes the target intermediate voltage Vt. , the intermediate capacitor 40 is charged from the power storage device 51 . At this time, since the switch 54 is in the OFF state, the intermediate capacitor 40 is charged from the power storage device 51 through the resistor 55 connected in parallel to the switch 54 .

<effect>
Next, the operation and effects of this embodiment will be described.
(1) The power supply device 10 includes an AC/DC converter 20 that converts AC power input from an AC power supply 110 into DC power, and a load converter 20 that converts the DC power output from the AC/DC converter 20 and supplies it to a load. DC/DC converter 30; intermediate capacitor 40 provided between AC/DC converter 20 and load DC/DC converter 30; It includes a plurality of power storage units 50 connected in parallel, and a control circuit 60 that controls the load DC/DC converter 30 and the plurality of power storage devices 51 .

In such a configuration, the plurality of power storage units 50 include a power storage device 51, a power storage DC/DC converter 53 that converts the power of the power storage device 51 and outputs the power to the intermediate capacitor 40, a power storage device 51 and a power storage DC/ A switch 54 provided between the DC converter 53 and a resistor 55 connected in parallel with the switch 54 are provided.

In such a configuration, when the control circuit 60 supplies power to the target power storage device 120 using the power storage device 51 in a situation where the input voltage Vac from the AC power supply 110 to the AC/DC converter 20 is equal to or lower than the determination voltage V1, Processing in step S26 of charging the intermediate capacitor 40 by operating the power storage DC/DC converter 53 with the switch 54 in the OFF state so that the intermediate voltage Vm becomes equal to or higher than the voltage Vdc of the power storage device 51. to run.

According to this configuration, since the power storage unit 50 is connected in parallel with the load DC/DC converter 30, there is no power supply from the AC power supply 110, and the input voltage Vac from the AC power supply 110 is equal to or lower than the determination voltage V1. Even when the load DC/DC converter 30 and the power storage DC/DC converter 53 are operated, power can be supplied to the target power storage device 120 using the power storage device 51 of the power storage unit 50. .

Here, when input voltage Vac is equal to or lower than determination voltage V1, intermediate voltage Vm may be lower than voltage Vdc of power storage device 51 . In this case, unintended power transmission may occur. On the other hand, if power storage device 51 and intermediate capacitor 40 are connected in a state where intermediate capacitor 40 is not charged, an excessive current may flow.

In this regard, according to this configuration, by operating the power storage DC/DC converter 53 with the switch 54 in the OFF state, power is transmitted from the power storage device 51 to the intermediate capacitor 40 via the resistor 55. Intermediate voltage Vm becomes equal to or higher than voltage Vdc of power storage device 51 .

Thereby, the intermediate voltage Vm can be set to the voltage Vdc of the power storage device 51 while suppressing excessive current flow. Therefore, power can be suitably supplied to the target power storage device 120 using the power storage device 51 thereafter.

(2) The power supply device 10 includes a plurality of power storage units 50 , and each of the plurality of power storage units 50 includes a power storage device 51 .
In such a configuration, the control circuit 60 controls the power storage DC while the switch 54 is in the OFF state so that the intermediate voltage Vm, which is the voltage of the intermediate capacitor 40, is higher than the maximum value of the voltages Vdc of the plurality of power storage devices 51. The processing of steps S24 to S26 for operating the /DC converter 53 is executed.

According to such a configuration, since the intermediate voltage Vm is boosted to a voltage higher than the maximum value of the voltages Vdc of the plurality of power storage devices 51, for example, unintended power transmission from one power storage device 51 to another power storage device 51 is suppressed. can. Therefore, it is possible to suppress a decrease in efficiency of power supply to target power storage device 120 due to unintended power transmission.

(3) Control circuit 60 discharges power storage device 51 among power storage units 50 at a predetermined SOC in a situation where input voltage Vac from AC power supply 110 to AC/DC converter 20 is equal to or lower than determination voltage V1. The process of step S21 is performed to determine whether or not there is an allowable power storage unit 50a having an allowable power storage device 51a with an allowable value SOC1 or more.

In such a configuration, the control circuit 60 performs the process of step S28 of supplying power to the target power storage device 120 using the allowable power storage device 51a when it is determined in step S21 that there is the allowable power storage device 51a.

In such a configuration, the control circuit 60 controls the allowable power storage unit 50a to turn off the allowable switch 54a of the allowable power storage unit 50a so that the intermediate voltage Vm becomes equal to or higher than the voltage Vdc of the allowable power storage device 51a. The processing of step S26 for operating the /DC converter 53a is executed.

According to such a configuration, electric power is supplied to target power storage device 120 using power storage device 51 having an SOC equal to or higher than discharge allowable value SOC1. A power storage device 51 with a low SOC is more likely to deteriorate due to discharge than a power storage device 51 with a high SOC. Therefore, according to this configuration, it is possible to suppress the deterioration of the power storage device 51 caused by supplying electric power to the target power storage device 120 using the power storage device 51 with a low SOC. As a result, the life of the power supply device 10 can be extended.

(4) When there are a plurality of allowable power storage devices 51a, the control circuit 60 performs the process of step S23 of supplying power to the target power storage device 120 using the one with the highest SOH among the plurality of allowable power storage devices 51a. .

According to such a configuration, power is supplied to the target power storage device 120 using the allowable power storage device 51a that is relatively undegraded. As a result, the frequency of power supply to the target power storage device 120 using the relatively deteriorated power storage device 51 is reduced, so that progress of deterioration of the power storage device 51 can be suppressed. Therefore, it is possible to suppress excessive deterioration of a specific power storage device 51 .

(5) The control circuit 60 performs power supply from at least one of the power storage devices 51 to the target power storage device 120 via the switch 54 after the intermediate capacitor 40 is charged by the process of step S26. The processes of steps S28 and S29 are executed to operate the load DC/DC converter 30 and the power storage DC/DC converter 53 while the switch 54 is in the ON state.

According to such a configuration, when power is supplied to the target power storage device 120 , the power of the power storage device 51 is supplied to the target power storage device 120 via the switch 54 having a smaller loss than the resistor 55 . Accordingly, power consumption by the resistor 55 can be suppressed when power is supplied to the target power storage device 120 . Therefore, a decrease in the power conversion efficiency of the power supply device 10 can be suppressed.

(6) When the target power storage device 120 is charged using the power storage device 51 in a situation where the input voltage Vac from the AC power supply 110 to the AC/DC converter 20 is equal to or lower than the determination voltage V1, the control circuit 60 controls the intermediate voltage The processes of steps S24 to S26 are executed to operate the power storage DC/DC converter 53 with the switch 54 turned off so that Vm is higher than the target voltage Vr, which is the voltage of the target power storage device 120 .

According to such a configuration, the target power storage device 120 can be charged by the step-down conversion performed by the load DC/DC converter 30 . In addition, reverse flow of electric power from the target power storage device 120 to the power storage device 51 can be suppressed.

<Modification>
Embodiments can be implemented with the following modifications. The embodiments and the following modified examples can be implemented in combination with each other within a technically consistent range.

(circle) the control sequence in embodiment is an illustration to the last, and is not restricted to embodiment. For example, the control circuit 60 may perform the process of step S10 or step S20 together with step S1.

○ The target intermediate voltage Vt may be the maximum value Vmax.
O The power storage device 51 used to supply power to the target power storage device 120 is not limited to the effective power storage device 51b. For example, the power storage device 51 may be the allowable power storage device 51a, or may be a power storage device 51 other than the allowable power storage device 51a.

○ The power storage device 51 used to charge the intermediate capacitor 40 is not limited to the allowable power storage device 51a having the highest SOH, and may be another allowable power storage device 51a or a power storage device 51 other than the allowable power storage device 51a. . When power is supplied from the power storage device 51 other than the allowable power storage device 51a to the target power storage device 120, the control circuit 60 does not need to execute step S21 corresponding to the allowable determination unit.

O The number of power storage units 50 may not be plural, and may be one. In other words, the power supply device 10 may include one or a plurality of power storage units 50 .
O The number of power storage devices 51 included in each power storage unit 50 is not limited to one, and may be plural.

O The target power storage device 120 may not be provided with the target BMS 121 . For example, instead of the target BMS 121, a voltage sensor for measuring the target voltage Vr of the target power storage device 120 may be provided separately. At this time, the control circuit 60 may specify the maximum value Vmax and set the target intermediate voltage Vt based on the target voltage Vr that can be obtained from the voltage sensor.

○ When the load is the target power storage device 120 as in the present embodiment, the load DC/DC converter 30 may be treated as one of the power storage DC/DC converters 53 . For example, the control circuit 60 supplies the load DC from the target power storage device 120 while the load switch 31 is in the OFF state so that the intermediate capacitor 40 is charged from the target power storage device 120 via the load resistor 32 . /DC converter 30 may be operated.

O The load is not limited to the target power storage device 120, and any drive device capable of supplying DC power, such as a resistor or a DC motor, can be used. In this case, the target voltage Vr is the voltage required to drive the driving device.

DESCRIPTION OF SYMBOLS 10... Power supply device, 20... AC/DC converter, 30... Load DC/DC converter, 40... Intermediate capacitor, 50... Electric storage unit, 51... Electric storage apparatus, 51a... Allowable electric storage apparatus, 53... DC/DC converter for electric storage , 54... Switch, 55... Resistance, 60... Control circuit, 110... AC power supply, 120... Target power storage device, SOC1... Discharge allowable value, V1... Judgment voltage, Vac... Input voltage, Vdc... Voltage of power storage device, Vm... Intermediate voltage, Vmax: maximum value, Vr: target voltage.

Claims (6)

an AC/DC converter that converts AC power input from an AC power supply into DC power;
a load DC/DC converter that converts the DC power output from the AC/DC converter and supplies it to a load;
an intermediate capacitor provided between the AC/DC converter and the load DC/DC converter;
one or more power storage units connected to the intermediate capacitor and connected in parallel to the load DC/DC converter;
a control circuit that controls the load DC/DC converter and the one or more power storage units,
The one or more power storage units are
a power storage device;
a power storage DC/DC converter that converts the power of the power storage device and outputs the power toward the intermediate capacitor;
a switch provided between the power storage device and the power storage DC/DC converter;
a resistor connected in parallel with the switch;
The control circuit is
When the power storage device is used to supply power to the load in a situation where the input voltage from the AC power supply to the AC/DC converter is equal to or lower than the judgment voltage, the intermediate voltage, which is the voltage of the intermediate capacitor, is applied to the power storage device. a power supply device, comprising a pre-charging unit that charges the intermediate capacitor by operating the power storage DC/DC converter with the switch in the OFF state so that the voltage of the intermediate capacitor is equal to or higher than the voltage of . comprising a plurality of said power storage units,
each of the plurality of power storage units includes the power storage device,
The pre-charging unit operates the power storage DC/DC converter with the switch turned off so that the intermediate voltage is higher than the maximum value of the voltages of the plurality of power storage devices. 2. The power supply device according to 1. The control circuit controls the SOC of the power storage device among the one or more power storage units to be equal to or higher than a predetermined discharge allowable value in a situation where the input voltage from the AC power supply to the AC/DC converter is equal to or lower than a judgment voltage. a permissible power storage unit that determines whether or not there is an allowable power storage unit having the permissible power storage device, and if the allowable power storage unit is determined to exist, the allowable power storage device is used to determine It supplies power to the load,
The pre-charging unit operates the power storage DC/DC converter of the allowable power storage unit while the switch of the allowable power storage unit is in an OFF state so that the intermediate voltage becomes equal to or higher than the voltage of the allowable power storage device. 3. The power supply device according to claim 1 or 2, which operates. 4. The power supply device according to claim 3, wherein, when there are a plurality of allowable power storage devices, said control circuit supplies power to said load using one of said plurality of allowable power storage devices with the highest SOH. The control circuit turns on the switch so that power is supplied from at least one of the power storage devices to the load via the switch after the intermediate capacitor is charged by the precharging unit. The power supply device according to any one of claims 1 to 4, wherein the load DC/DC converter and the power storage DC/DC converter are operated in a state of being set. the load is a target power storage device that can be charged,
The pre-charging unit charges the target power storage device using the power storage device in a situation where the input voltage from the AC power supply to the AC/DC converter is equal to or lower than the determination voltage, and the intermediate voltage is The power supply device according to any one of claims 1 to 5, wherein the power storage DC/DC converter is operated with the switch turned off so that the voltage becomes higher than the voltage of the target power storage device.

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