阅读说明：本技术 一种电源变换器、充电机、充电系统及方法 (Power converter, charger, charging system and method ) 是由 张维 程洋 崔兆雪 于 2020-04-07 设计创作，主要内容包括：本申请公开了一种电源变换器、充电机、充电系统及方法,该电源变换器包括：功率因数校正PFC电路、直流母线电容、功率变换电路和控制器；PFC电路的第一端用于连接交流电,PFC电路的第二端用于连接功率变换电路的第一端,直流母线电容并联在PFC电路的第二端；功率变换电路,用于在控制器的控制下将设备提供的电能转换后给直流母线电容充电；控制器,用于在PFC电路的第一端接通交流电之前控制功率变换电路将设备提供的电能转换后给直流母线电容充电。该电源变换器无需额外增加预充电路等硬件设备,减小了电源变换器的体积以及降低了电源变换器的生产成本。(The application discloses power converter, charger, charging system and method, this power converter includes: the power factor correction PFC circuit comprises a PFC circuit, a DC bus capacitor, a power conversion circuit and a controller; the first end of the PFC circuit is used for connecting alternating current, the second end of the PFC circuit is used for connecting the first end of the power conversion circuit, and the direct-current bus capacitor is connected to the second end of the PFC circuit in parallel; the power conversion circuit is used for converting electric energy provided by the equipment under the control of the controller and then charging the direct current bus capacitor; and the controller is used for controlling the power conversion circuit to convert the electric energy provided by the equipment before the first end of the PFC circuit is connected with the alternating current and then charge the direct current bus capacitor. The power converter does not need to additionally add hardware equipment such as a pre-charging circuit and the like, reduces the size of the power converter and reduces the production cost of the power converter.)

1. A power converter, comprising: the power factor correction PFC circuit comprises a PFC circuit, a DC bus capacitor, a power conversion circuit and a controller;

the first end of the PFC circuit is used for connecting alternating current, the second end of the PFC circuit is used for connecting the first end of the power conversion circuit, and the direct-current bus capacitor is connected to the second end of the PFC circuit in parallel;

the power conversion circuit is used for converting the direct current output by the PFC circuit under the control of the controller and outputting the converted direct current to equipment, and is also used for converting electric energy provided by the equipment and charging the direct current bus capacitor under the control of the controller;

the controller is used for controlling the power conversion circuit to convert the electric energy provided by the equipment before the first end of the PFC circuit is connected with the alternating current and then charge the direct current bus capacitor; and the power conversion circuit is further used for controlling the first end of the PFC circuit to be connected with the alternating current when the voltage of the direct current bus capacitor reaches a preset voltage, so that the power conversion circuit converts the direct current output by the PFC circuit and outputs the direct current to the equipment.

2. The power converter of claim 1, wherein the power conversion circuit comprises: a DC-DC circuit;

the first end of the DC-DC circuit is used for connecting the second end of the PFC circuit, and the second end of the DC-DC circuit is used for connecting the equipment.

3. The power converter of claim 2, wherein the DC-DC circuit comprises a primary side switching circuit, a transformer, and a secondary side switching circuit;

the apparatus includes a battery;

the first end of the primary side switch circuit is used for being connected with the second end of the PFC circuit;

the second end of the primary side switching circuit is used for connecting a primary side winding of the transformer;

the secondary winding of the transformer is connected with the first end of the secondary switching circuit, and the second end of the secondary switching circuit is used for connecting the storage battery;

the controller is specifically configured to control the power conversion circuit to convert the electric energy provided by the storage battery and then charge the dc bus capacitor.

4. The power converter of claim 3, wherein the battery comprises a high voltage battery and a low voltage battery;

the controller is specifically configured to control the power conversion circuit to convert the electric energy provided by the low-voltage battery or the high-voltage battery and then charge the dc bus capacitor.

5. The power converter of claim 4, wherein the secondary side switching circuit comprises: a secondary high-voltage switch circuit and a secondary low-voltage switch circuit; the secondary winding of the transformer comprises a first secondary winding and a second secondary winding;

the first secondary winding is connected with a first end of the secondary high-voltage switch circuit, and a second end of the secondary high-voltage switch circuit is used for connecting the high-voltage battery;

the second secondary winding is connected with the first end of the secondary low-voltage switch circuit, and the second end of the secondary low-voltage switch circuit is used for connecting the low-voltage battery;

the controller is specifically configured to control the secondary low-voltage switch circuit to supply the energy of the low-voltage battery to a second secondary winding of the transformer, so that the power conversion circuit converts the electric energy supplied by the low-voltage battery and charges the dc bus capacitor.

6. A power converter as claimed in any one of claims 1 to 5, wherein the predetermined voltage is the peak voltage of the alternating current.

7. The utility model provides a machine charges which characterized in that is applied to electric automobile, includes: the device comprises a Power Factor Correction (PFC) circuit, a direct-current bus capacitor, a DC-DC circuit and a charger controller;

the first end of the PFC circuit is used for being connected with an alternating current charging interface, the second end of the PFC circuit is used for being connected with the first end of the DC-DC circuit, and the direct current bus capacitor is connected to the second end of the PFC circuit in parallel;

the DC-DC circuit is used for converting the direct current output by the PFC circuit under the control of the charger controller and then charging a storage battery on the electric automobile, and is also used for converting the electric energy provided by the storage battery under the control of the charger controller and then charging the direct current bus capacitor;

the charger controller is used for controlling the DC-DC circuit to convert the electric energy provided by the storage battery and then charge the direct-current bus capacitor before the first end of the PFC circuit is connected with the alternating current; and the DC-DC circuit is also used for controlling the first end of the PFC circuit to be connected with the alternating current when the voltage of the direct current bus capacitor reaches a preset voltage, so that the DC-DC circuit converts the direct current output by the PFC circuit and then charges the storage battery.

8. The charger according to claim 7, characterized in that said accumulator comprises a low-voltage battery;

the charger controller is specifically configured to control the DC-DC circuit to convert the electric energy provided by the low-voltage battery and then charge the DC bus capacitor.

9. The charger according to claim 8, characterized in that said battery further comprises: a high voltage battery; the DC-DC circuit comprises a primary side switch circuit, a transformer, a secondary side high-voltage switch circuit and a secondary side low-voltage switch circuit;

the first end of the primary side switch circuit is connected with the second end of the PFC circuit;

the second end of the primary side switching circuit is connected with the primary side winding of the transformer;

the first secondary winding of the transformer is connected with the first end of the secondary high-voltage switch circuit, and the second end of the secondary high-voltage switch circuit is used for connecting the high-voltage battery;

the second secondary winding of the transformer is connected with the first end of the secondary low-voltage switch circuit, and the second end of the secondary low-voltage switch circuit is used for connecting the low-voltage battery;

the controller is specifically configured to control the secondary low-voltage switch circuit to supply the energy of the low-voltage battery to a second secondary winding of the transformer, so that the DC-DC circuit converts the electric energy supplied by the low-voltage battery and charges the DC bus capacitor.

10. An electrical charging system, comprising: a charger and a power supply device;

the power supply equipment is used for sending charging starting request information to the charger before supplying electric energy to the charger;

the charger is used for sending feedback information of the charging starting request information to the power supply equipment when the voltage of the direct current bus capacitor reaches a preset voltage;

and the power supply equipment is also used for supplying electric energy to the charger after receiving the feedback information.

11. The charging system according to claim 10, characterized in that the charger is according to any one of claims 7-9.

12. A method of pre-charging applied to a first device comprising a power converter and a battery, the power converter comprising a dc bus capacitor for energy storage and filtering, the method comprising:

receiving charging starting request information sent by power supply equipment;

responding to the charging starting request information, and charging the direct current bus capacitor by using the electric energy provided by the storage battery;

and when the voltage of the direct current bus capacitor reaches a preset voltage, sending feedback information of the charging starting request information to the power supply equipment so that the power supply equipment provides electric energy for the charger through the power supply interface.

Technical Field

The application relates to the technical field of power electronics, in particular to a power converter, a charger, a charging system and a charging method.

Background

As shown in fig. 1, the power converter generally includes an electromagnetic interference (EMC) circuit 100, a Power Factor Correction (PFC) circuit 200, a DC bus capacitor C, and a DC-DC (DC-DC) circuit 300 in a preceding stage if an input is an ac power and an output is a DC power. As shown in fig. 2, if the input is AC and the output is AC, the difference from fig. 1 is that the final stage circuit is a direct current-alternating current (DC-AC) circuit 400 instead of the DC-DC circuit 300.

With regard to fig. 1 and 2, when the input end of the power converter is connected with the ac power, the ac power is directly connected to the dc bus capacitor C, and at this time, a large inrush current is generated to cause damage to devices in each circuit, so that it is necessary to control the voltage of the dc bus capacitor to slowly increase in order to prevent the inrush current from being too large. When the voltage of the bus capacitor rises, the normal power conversion is carried out, and the safety of devices in each circuit is further ensured.

In order to solve the above problems, in the prior art, a pre-charge circuit 500 is added before the PFC circuit 200, referring to fig. 3, when the input terminal of the power converter is connected with the ac power, the relay K is controlled to be turned off, at this time, the dc bus capacitor C is charged through the soft-start resistor R, and when the voltage on C reaches a certain value, the relay K is turned on, and then the power conversion is started.

However, this solution has the disadvantage of requiring the pre-charge circuit 500 to be added before the PFC circuit 200, which adds to the size and cost of the power converter.

Disclosure of Invention

In order to solve the technical problems, the application provides a power converter, a charger, a charging system and a charging method, which can charge a direct current bus capacitor before alternating current is switched on without increasing the size and cost of the power converter.

In a first aspect, the present application provides a power converter comprising: the power factor correction PFC circuit comprises a PFC circuit, a DC bus capacitor, a power conversion circuit and a controller; the first end of the PFC circuit is used for connecting alternating current, the second end of the PFC circuit is used for connecting the first end of the power conversion circuit, and the direct-current bus capacitor is connected to the second end of the PFC circuit in parallel; the power conversion circuit is used for converting the direct current output by the PFC circuit and outputting the converted direct current to equipment under the control of the controller, and is also used for converting electric energy provided by the equipment and charging a direct current bus capacitor under the control of the controller; the controller is used for controlling the power conversion circuit to convert the electric energy provided by the equipment before the first end of the PFC circuit is connected with the alternating current and then charge the direct current bus capacitor; and the power conversion circuit is also used for controlling the first end of the PFC circuit to be communicated with the alternating current when the voltage of the direct current bus capacitor reaches a preset voltage, so that the power conversion circuit converts the direct current output by the PFC circuit and outputs the direct current to equipment.

The power converter is not added with new hardware and comprises a PFC circuit, a direct-current bus capacitor, a power conversion circuit and a controller. Before the alternating current is connected with the PFC circuit, the controller controls the power conversion circuit to convert electric energy provided by the equipment and then charge the direct current bus capacitor, and when the voltage of the direct current bus capacitor reaches a preset voltage, the first end of the PFC circuit is controlled to be connected with the alternating current. Therefore, the situation that the alternating current is directly connected to the direct current bus capacitor C to generate large impact current and damage devices in the PFC circuit is caused is avoided. The power converter utilizes the existing hardware, realizes the pre-charging of the direct current bus capacitor through the control of the controller, does not need to additionally add hardware equipment such as a pre-charging circuit and the like, reduces the volume of the power converter and reduces the production cost of the power converter.

Preferably, the power conversion circuit includes: a DC-DC circuit; the first end of the DC-DC circuit is used for connecting the second end of the PFC circuit, and the second end of the DC-DC circuit is used for connecting equipment.

Preferably, the DC-DC circuit comprises a primary side switching circuit, a transformer and a secondary side switching circuit; the device comprises a storage battery; the first end of the primary side switching circuit is used for connecting the second end of the PFC circuit; the second end of the primary side switching circuit is used for connecting a primary side winding of the transformer; the secondary winding of the transformer is connected with the first end of the secondary switching circuit, and the second end of the secondary switching circuit is used for connecting a storage battery; and the controller is specifically used for controlling the power conversion circuit to convert the electric energy provided by the storage battery and then charge the direct-current bus capacitor.

In this embodiment, the power conversion circuit of the power converter includes a primary side switch circuit, a transformer, and a secondary side switch circuit. The device that provides dc power to the dc bus capacitor may be a battery when the dc bus capacitor is pre-charged. The controller controls the secondary side switch circuit and the primary side switch circuit, and the direct current provided by the storage battery is converted by the transformer to charge the direct current bus capacitor. After the voltage of the direct current bus capacitor reaches the preset voltage, the power converter is connected with the alternating current, so that the situation that the alternating current is directly input into the direct current bus capacitor to generate large impact current and damage devices in the power converter is avoided. Further, after the power converter is switched on with alternating current, the controller controls the primary side switch circuit and the secondary side switch circuit to convert direct current output by the PFC circuit and charge the storage battery.

Preferably, the secondary battery includes a high-voltage battery and a low-voltage battery; and the controller is specifically used for controlling the power conversion circuit to convert the electric energy provided by the low-voltage battery or the high-voltage battery and then charge the direct-current bus capacitor.

Preferably, the secondary side switching circuit includes: a secondary high-voltage switch circuit and a secondary low-voltage switch circuit; the secondary winding of the transformer comprises a first secondary winding and a second secondary winding; the first secondary winding is connected with the first end of the secondary high-voltage switch circuit, and the second end of the secondary high-voltage switch circuit is used for connecting a high-voltage battery; the second secondary winding is connected with the first end of the secondary low-voltage switch circuit, and the second end of the secondary low-voltage switch circuit is used for connecting a low-voltage battery; and the controller is specifically used for controlling the secondary low-voltage switch circuit to supply the energy of the low-voltage battery to the second secondary winding of the transformer, so that the power conversion circuit converts the electric energy supplied by the low-voltage battery and then charges the direct-current bus capacitor.

The power converter can be applied to a charger of an electric automobile, and a DC-DC circuit of the power converter comprises a primary side switch circuit, a transformer, a secondary side high-voltage switch circuit and a secondary side low-voltage switch circuit. When the direct current bus capacitor is pre-charged, the direct current provided by the low-voltage battery of the electric automobile charges the direct current bus capacitor, so that the situation that the direct current is directly input to the direct current bus capacitor to generate large impact current and damage devices in the power converter is avoided. Because the voltage of the low-voltage battery is lower, the high-voltage electric shock hazard can not exist, and therefore, the low-voltage battery can be connected with the charger when not being charged. When the direct current bus capacitor needs to be precharged, the low-voltage battery is directly used for precharging the direct current bus capacitor, and the method is convenient and fast.

Preferably, the preset voltage is a peak voltage of the alternating current.

When the dc bus capacitor is precharged, the voltage of the dc bus capacitor reaches a predetermined voltage, and then the power converter is connected to the ac power, for example, the predetermined voltage is a peak voltage of the ac power. Because the voltage of the direct current bus capacitor reaches the peak voltage of the alternating current, larger impact current cannot be generated at the moment that the power converter is switched on the alternating current, and therefore damage to devices inside the power converter is avoided.

In a second aspect, the present application provides a charger applied to an electric vehicle, including: the device comprises a Power Factor Correction (PFC) circuit, a direct-current bus capacitor, a DC-DC circuit and a charger controller; the first end of the PFC circuit is used for connecting an alternating current charging interface, the second end of the PFC circuit is used for connecting the first end of the DC-DC circuit, and the direct-current bus capacitor is connected to the second end of the PFC circuit in parallel; the DC-DC circuit is used for converting the direct current output by the PFC circuit under the control of the charger controller and then charging a storage battery on the electric automobile, and is also used for converting the electric energy provided by the storage battery and then charging a direct current bus capacitor under the control of the charger controller; the charger controller is used for controlling the DC-DC circuit to convert the electric energy provided by the storage battery and then charge the direct-current bus capacitor before the first end of the PFC circuit is connected with the alternating current; and the control circuit is also used for controlling the first end of the PFC circuit to be communicated with the alternating current when the voltage of the direct current bus capacitor reaches a preset voltage, so that the DC-DC circuit converts the direct current output by the PFC circuit and then charges the storage battery.

The charger is not added with new hardware. The charger comprises a Power Factor Correction (PFC) circuit, a direct-current bus capacitor, a DC-DC circuit and a charger controller. Before the charger is connected with the power supply interface, the charger controller controls the DC-DC circuit to charge the direct current provided by the storage battery to the direct current bus capacitor by using the existing hardware, and hardware equipment such as a pre-charging circuit and the like is not required to be additionally added, so that the volume of the charger is reduced, and the production cost of the charger is reduced.

Preferably, the battery comprises a low voltage battery; and the charger controller is specifically used for controlling the DC-DC circuit to convert the electric energy provided by the low-voltage battery and then charge the direct-current bus capacitor.

Preferably, the secondary battery further comprises: a high voltage battery; the DC-DC circuit comprises a primary side switch circuit, a transformer, a secondary side high-voltage switch circuit and a secondary side low-voltage switch circuit; the first end of the primary side switching circuit is connected with the second end of the PFC circuit; the second end of the primary side switching circuit is connected with a primary side winding of the transformer; the first secondary winding of the transformer is connected with the first end of the secondary high-voltage switch circuit, and the second end of the secondary high-voltage switch circuit is used for connecting a high-voltage battery; a second secondary winding of the transformer is connected with a first end of the secondary low-voltage switch circuit, and a second end of the secondary low-voltage switch circuit is used for connecting a low-voltage battery; and the controller is specifically used for controlling the secondary low-voltage switch circuit to supply the energy of the low-voltage battery to the second secondary winding of the transformer, so that the DC-DC circuit converts the electric energy supplied by the low-voltage battery and then charges the direct-current bus capacitor.

When the voltage of the direct current bus capacitor reaches a preset voltage, the charger controller controls the primary side switching circuit to input the direct current provided by the PFC circuit to the primary side winding of the transformer, the direct current is input to the first end of the secondary side low-voltage switching circuit through the second secondary side winding of the transformer T, and the secondary side low-voltage switching circuit is controlled to charge the direct current output by the PFC circuit to the low-voltage battery. The charger controller can also control the primary side switch circuit and the secondary side high-voltage switch circuit to charge the high-voltage battery.

In a third aspect, the present application provides a charging system, including a charger and a power supply device; the power supply equipment is used for sending charging starting request information to the charger before supplying electric energy to the charger; the charger is used for sending feedback information of the charging starting request information to the power supply equipment when the voltage of the direct current bus capacitor reaches a preset voltage; and the power supply equipment is also used for supplying electric energy to the charger after receiving the feedback information.

Preferably, the charger is any one of the chargers of the second aspect of the present application.

When the charger charges, the power supply equipment sends charging starting request information to the charger controller; after the charger controller receives the charging starting request information, the charger controller controls the DC-DC circuit to convert the electric energy provided by the low-voltage battery and then charge the direct-current bus capacitor; when the charger controller confirms that the voltage of the direct-current bus capacitor reaches a preset voltage, feedback information is sent to the power supply equipment; after receiving the feedback information, the power supply equipment controls the internal switch K1 and the switch K2 to be closed, and provides electric energy for the charger through the power supply interface. By using the charging system, when the electric automobile charges the electric automobile by using the charger, new hardware does not need to be added in the charger of the electric automobile. The existing hardware of the charger is utilized, the direct current bus capacitor is precharged under the control of the charger controller, hardware equipment such as a precharge circuit and the like is not required to be additionally added, the size of the charger is reduced, and the production cost of the charger is reduced.

In a fourth aspect, the present application provides a pre-charging method, which is applied to a first device, the first device includes a power converter and a storage battery, the power converter includes a dc bus capacitor for energy storage and filtering, and the method includes: receiving charging starting request information sent by power supply equipment; responding to the charging starting request information, and charging the direct current bus capacitor by using the electric energy provided by the storage battery; and when the voltage of the direct current bus capacitor reaches the preset voltage, sending feedback information of the charging starting request information to the power supply equipment so that the power supply equipment provides electric energy for the charger through the power supply interface.

The method controls the first equipment comprising the power converter and the storage battery, does not need to additionally add new hardware in the power converter, and can complete the pre-charging of the capacitance of the direct current bus by utilizing the existing hardware equipment in the power converter before the power converter is switched on. Therefore, hardware devices such as a pre-charging circuit and the like do not need to be additionally arranged, the size of the power converter is reduced, and the generation cost of the power converter is reduced. When the voltage of the direct current bus capacitor reaches the preset voltage, feedback information of the charging starting request information is sent to the power supply equipment, and the power supply equipment provides electric energy for the power converter through the power supply interface, so that the situation that the device in the PFC circuit is damaged due to the fact that the alternating current is directly connected to the direct current bus capacitor to generate large impact current is avoided.

The application has at least the following advantages:

the power converter is not added with new hardware and comprises a PFC circuit, a direct-current bus capacitor, a power conversion circuit and a controller. Before the alternating current is connected with the PFC circuit, the controller controls the power conversion circuit to convert electric energy provided by the equipment and then charge the direct current bus capacitor, and when the voltage of the direct current bus capacitor reaches a preset voltage, the first end of the PFC circuit is controlled to be connected with the alternating current. Therefore, the situation that the alternating current is directly connected to the direct current bus capacitor C to generate large impact current and damage devices in the PFC circuit is caused is avoided. In the technical scheme of the application, the pre-charging of the direct-current bus capacitor is realized through the control of the controller by utilizing the existing hardware, hardware equipment such as a pre-charging circuit and the like is not required to be additionally added, the size of the power converter is reduced, and the production cost of the power converter is reduced.

Drawings

FIG. 1 is a schematic diagram of a power converter;

FIG. 2 is a schematic diagram of another power converter;

FIG. 3 is a schematic diagram of yet another power converter;

fig. 4 is a schematic diagram of a power converter according to an embodiment of the present application;

FIG. 5 is a schematic diagram of another power converter provided in an embodiment of the present application;

fig. 6 is a schematic diagram of another power converter provided in an embodiment of the present application;

FIG. 7 is a schematic diagram of another power converter provided in an embodiment of the present application;

fig. 8 is a schematic diagram of a charger according to an embodiment of the present application;

fig. 9 is a schematic diagram of another charger according to an embodiment of the present application;

FIG. 10 is a schematic diagram of a DC-DC circuit according to an embodiment of the present application;

FIG. 11 is a schematic diagram of another DC-DC circuit provided by an embodiment of the present application;

fig. 12 is a schematic diagram of a charging system according to an embodiment of the present disclosure;

fig. 13 is a schematic diagram of another charging system provided in the embodiment of the present application;

fig. 14 is a flowchart of a precharging method according to an embodiment of the present disclosure.

Detailed Description

The power converter is used for converting the power supply of the input end and supplying the converted electric energy to the rear-end equipment, but the input end of the power converter generates larger impact current at the moment of switching on the power supply, so that internal devices are damaged. According to the technical scheme provided by the embodiment of the application, before the power converter is powered on, the direct current bus capacitor in the power converter is charged by utilizing subsequent equipment, the voltage of the direct current bus capacitor is increased, and then the power converter is powered on, so that the situation that the internal devices are damaged by impact current generated by directly powering on the power converter is avoided.

The embodiment of the present application is not limited to the application scenario of the Power converter, and for example, the Power converter may Supply Power to a server in each scenario, or a base station in a network device, or a backup Power Supply in the above various scenarios, such as an Uninterruptible Power Supply (UPS).

In addition, the power converter can also be applied to a vehicle-mounted charger of the electric automobile to charge a battery on the electric automobile.

In order to make those skilled in the art better understand the technical solutions provided in the embodiments of the present application, the technical solutions in the embodiments of the present application will be described below clearly with reference to the drawings in the embodiments of the present application.

First embodiment of the power converter:

referring to fig. 4, the diagram is a schematic diagram of a power converter according to an embodiment of the present application.

The power converter includes: the power factor correction PFC circuit 200, the direct current bus capacitor C, the power conversion circuit 600 and the controller 700.

The first end of the PFC circuit 200 is used for connecting an alternating current, the second end of the PFC circuit 200 is used for connecting the first end of the power conversion circuit 600, and the dc bus capacitor C is connected in parallel to the second end of the PFC circuit 200.

The PFC circuit 200 functions to rectify ac power into dc power and also to convert the dc power, for example, to boost the dc power.

The power conversion circuit 600 is configured to convert the dc power output by the PFC circuit 200 and output the converted dc power to the device 800 under the control of the controller, and is further configured to convert the electric energy provided by the device and charge the dc bus capacitor.

The controller 700 is configured to control the power conversion circuit 600 to convert the electric energy provided by the device 800 and charge the dc bus capacitor C before the ac power is switched on at the first end of the PFC circuit; and is further configured to control the first end of the PFC circuit 200 to be electrically connected to the alternating current when the voltage of the dc bus capacitor C reaches a preset voltage, so that the power conversion circuit converts the direct current output by the PFC circuit and outputs the converted direct current to the device.

In order to reduce the large current surge generated when the ac power is connected, the preset voltage may be set according to the voltage of the ac power connected to the first end of the PFC circuit 200, and generally may be set to be higher than the peak voltage value of the ac power.

When the input end of the power converter is connected with the alternating current, during normal operation, the electric energy is transmitted to the device 800 through the PFC circuit 200 and the power conversion circuit 600. However, in this embodiment, when the input terminal of the power converter is not connected to the ac power, the controller 700 controls the power from the device 800 to charge the dc bus capacitor C through the power conversion circuit 600.

The power converter provided by the embodiment does not add new hardware. When the device 800 needs to be supplied with electric energy, the PFC circuit 200 is not directly switched on with ac power, but the controller 700 controls the power conversion circuit 600 in advance to convert the electric energy supplied by the device 800 and then charge the dc bus capacitor C. The voltage of the dc bus capacitor C will increase, and when the voltage of the dc bus capacitor C increases to a preset voltage, the controller 700 controls the first terminal of the PFC circuit 200 to be in ac power connection. Because the controller 700 controls the power conversion circuit 600 in advance to raise the voltage of the dc bus capacitor C to the preset voltage, the situation that the devices in the PFC circuit 200 are damaged due to a large impact current generated when the ac power is directly connected to the dc bus capacitor C is avoided. In the technical solution of this embodiment, with the existing hardware, the controller 700 precharges the dc bus capacitor C by controlling the power transmission direction of the power conversion circuit 600, and does not need to add hardware devices such as a precharge circuit, thereby reducing the size of the power converter and reducing the production cost of the power converter.

In one possible embodiment, after the voltage of the dc bus capacitor C rises to the preset voltage, the controller 700 controls the first end of the PFC circuit 200 to be connected to the ac power, the PFC circuit 200 outputs the dc power, and the controller 700 controls the power conversion circuit 600 to convert the dc power output by the PFC circuit 200 and output the converted dc power to the device 800, so as to power the device 800.

The power conversion circuit 600 has a characteristic of bidirectional electric energy transfer, and under the control of the controller 700, the power conversion circuit 600 can transfer electric energy from the device 800 side to the dc bus capacitor C side and also can transfer electric energy from the dc bus capacitor C side to the device 800 side.

The process of the power conversion circuit 600 transferring the electric energy from the device 800 side to the dc bus capacitor C side may be: the controller 700 controls the power conversion circuit 600 to convert the electric energy provided by the device 800 and then charge the dc bus capacitor C.

In the process of transmitting the electric energy from the device 800 side to the dc bus capacitor C side by the power conversion circuit 600 under the control of the controller 700, the electric energy provided by the device 800 may be dc or ac.

The process of the power conversion circuit 600 transmitting the electric energy from the side C of the dc bus capacitor to the side 800 may be: the controller 700 controls the power conversion circuit 600 to convert the electric energy output by the PFC circuit 200, and then outputs the dc power to charge the device 800.

In the process that the power conversion circuit 600 transmits the electric energy from the side of the dc bus capacitor C to the side of the device 800 under the control of the controller 700, the electric energy output by the power conversion circuit 600 may be dc or ac. When the power conversion circuit 600 outputs an alternating current, the power conversion circuit 600 includes an inverter circuit in addition to a DC-DC circuit.

Before the input end of the power converter is connected to the ac power, the controller 700 controls the power conversion circuit 600, so that the dc power provided by the device 800 can be converted to charge the dc bus capacitor C, and the ac power provided by the device 800 can be converted to charge the dc bus capacitor C. After the voltage of the dc bus capacitor C reaches the preset voltage, the controller 700 controls the power conversion circuit 600 to convert the dc power input by the PFC circuit 200 and output the dc power to charge the device 800, or convert the dc power input by the PFC circuit 200 and output the ac power to charge the device 800. The adaptation range of the power converter is further improved.

Second embodiment of power converter:

for the convenience of understanding, the following briefly describes an application scenario of the power converter in the present embodiment, which is capable of outputting a direct current to supply power to a device requiring the direct current.

Referring to fig. 5, a schematic diagram of another power converter provided in the embodiments of the present application is shown.

The power conversion circuit 600 of the power converter includes a DC-DC circuit 610.

The controller 700 can control the DC-DC circuit 610 to convert the DC power provided by the device 800 to charge the DC bus capacitor C.

When the voltage of the dc bus capacitor C reaches a preset voltage, the controller 700 controls the first terminal of the PFC circuit 200 to be connected to the ac power. Therefore, the situation that the alternating current is directly connected to the direct current bus capacitor C to generate larger impact current and damage devices in the PFC circuit 200 is avoided.

Referring to fig. 6, a schematic diagram of another power converter provided in the embodiment of the present application is shown.

The DC-DC circuit 610 of the power converter includes: a primary side switching circuit 611, a transformer T, and a secondary side switching circuit 612.

Wherein the apparatus 800 comprises: and a battery 810.

A first terminal of the primary side switching circuit 611 is connected to a second terminal of the PFC circuit 200.

The second terminal of the primary side switching circuit 611 is connected to the primary side winding of the transformer T.

The secondary winding of the transformer T is connected to a first terminal of the secondary switching circuit 612, and a second terminal of the secondary switching circuit 612 is used for charging the battery 810.

And the controller 700 is configured to control the power conversion circuit 600 to convert the electric energy provided by the storage battery 810 and then charge the dc bus capacitor C.

The controller 700 of the power converter can control the primary side switch circuit 611 and the secondary side switch circuit 612 to convert the direct current provided by the storage battery 810 through the transformer T and then charge the direct current bus capacitor C.

In one possible embodiment, when the dc bus capacitor C is precharged, the controller 700 controls the secondary switching circuit 612 to input the dc power provided by the battery 810 to the secondary winding of the transformer T, the secondary winding and the primary winding are coupled via a magnetic field to provide power as the primary winding of T, the primary winding of T is provided to the first end of the primary switching circuit 611, and the dc bus capacitor C is charged through the primary switching circuit 611.

After the voltage of the dc bus capacitor C reaches the preset voltage, the controller 700 controls the first terminal of the PFC circuit 200 to be electrically connected to the ac. The controller 700 controls the primary side switching circuit 611 and the secondary side switching circuit 612 to charge the battery 810.

In this embodiment, the power conversion circuit 600 of the power converter includes a primary side switch circuit 611, a transformer T, and a secondary side switch circuit 612. The device 800 that provides dc power to the dc bus capacitor C may be a battery 810 when the dc bus capacitor C is pre-charged. The controller 700 controls the secondary side switching power 611 and the primary side switching circuit 612, and converts the dc power provided by the battery 810 through the transformer T to charge the dc bus capacitor C. After the voltage of the direct current bus capacitor C reaches the preset voltage, the power converter is connected with the alternating current, so that the situation that the alternating current is directly input to the direct current bus capacitor C to generate large impact current and damage devices in the power converter is avoided. Further, after the power converter switches on the ac power, the controller 700 controls the primary side switching circuit 611 and the secondary side switching circuit 612 to convert the dc power output by the PFC circuit 200, and then charges the battery.

Third embodiment of the power converter:

for convenience of understanding, the following description briefly describes a scenario in which the power converter in the present embodiment is applied to a charger of an electric vehicle. The power converter may be located inside the charger.

Referring to fig. 7, a schematic diagram of another power converter provided in the embodiment of the present application is shown.

In the present embodiment, when applied to an electric vehicle, the storage battery 810 of the electric vehicle may include a high-voltage battery 810a and a low-voltage battery 810 b.

The high-voltage battery 810a is used for supplying electric energy to a motor of the electric automobile; the low-voltage battery 810b is used to supply electric power to the control system and auxiliary devices of the electric vehicle.

The controller 700 of the power converter controls the power conversion circuit 600 to convert the electric energy provided by the high-voltage battery 810a or the low-voltage battery 810b and then charge the dc bus capacitor C.

The DC-DC circuit 610 of the power converter includes a primary side switching circuit 611, a transformer T, a secondary side high voltage switching circuit 612a, and a secondary side low voltage switching circuit 612 b.

A first terminal of the primary side switching circuit 611 is connected to a second terminal of the PFC circuit 200.

The second terminal of the primary side switching circuit 611 is connected to the primary side winding of the transformer T.

The secondary winding of the transformer T includes a first secondary winding and a second secondary winding.

The first secondary winding is connected to a first terminal of the secondary high-voltage switch circuit 612a, and a second terminal of the secondary high-voltage switch circuit 612a is used for charging the high-voltage battery 810 a.

The second secondary winding is connected to a first terminal of a secondary low voltage switch circuit 612b, and a second terminal of the secondary low voltage switch circuit 612b is used to charge the low voltage battery 810 b.

The controller 700 of the power converter controls the primary side switch circuit 611 and the secondary side high voltage switch circuit 612a, and converts the electric energy provided by the high voltage battery 810a and then provides the converted electric energy to the direct current bus capacitor C; or, the controller 700 of the power converter controls the primary side switching circuit 611 and the secondary side low voltage switching circuit 612b to convert the electric energy provided by the low voltage battery 810b and then supply the converted electric energy to the dc bus capacitor C.

The battery 810 of the electric vehicle includes a high-voltage battery 810a and a low-voltage battery 810 b; the high-voltage battery 810a provides higher voltage and can provide running power for the whole vehicle; the low voltage battery 810b provides a lower voltage, which can provide electrical energy to the control system and auxiliary devices of the vehicle. The low-voltage battery 810b provides a lower voltage and higher safety than the high-voltage battery 810 a. The low voltage battery 810b may be always connected to the secondary low voltage switch circuit 612 b. If the high-voltage battery 810a is always connected to the secondary high-voltage switch circuit 612a, there is a risk of causing a safety accident. Therefore, when the high-voltage battery 810a is not charged, the connection between the high-voltage battery 810a and the secondary high-voltage switch circuit 612a can be disconnected.

The technical solution of the embodiment of the present application is described below by taking the low-voltage battery 810b of the electric vehicle as an example for pre-charging the dc bus capacitor C.

In one possible embodiment, the power converter may be applied to a charger of an electric vehicle, and the dc bus capacitor C of the power converter inside the charger is pre-charged before the charger is connected to ac power. The controller 700 controls the secondary low-voltage switch circuit 612b to input the dc power provided by the low-voltage battery 810b to the second secondary winding of the transformer T, and the dc power is provided to the first end of the primary switch circuit 611 via the primary winding of the transformer T, and the controller 700 controls the primary switch circuit 611 to charge the dc bus capacitor C.

After the voltage of the dc bus capacitor C reaches the preset voltage, the controller 700 controls the first terminal of the PFC circuit 200 to be electrically connected to the ac.

After the PFC circuit 200 is switched on with the ac power, the controller 700 controls the primary side switching circuit 611 to input the dc power provided by the PFC circuit 200 to the primary side winding of the transformer T, and provides the dc power to the first end of the secondary side high voltage switching circuit 612a through the first secondary side winding of the transformer T, so as to control the secondary side high voltage switching circuit 612a to charge the high voltage battery 810a with the dc power output by the PFC circuit 200.

After the PFC circuit 200 is switched on with the ac power, the controller 700 controls the primary side switching circuit 611 to input the dc power provided by the PFC circuit 200 to the primary side winding of the transformer T, and input the dc power to the first end of the secondary side low voltage switching circuit 612b through the second secondary side winding of the transformer T, and controls the secondary side low voltage switching circuit 612b to charge the low voltage battery 810b with the dc power output by the PFC circuit 200.

In this embodiment, the charging of the high-voltage battery 810a and/or the low-voltage battery 810b of the electric vehicle is not limited, and may be determined according to actual conditions of the high-voltage battery 810a and the low-voltage battery 810 b.

In addition, when the dc bus capacitor C is precharged, the voltage of the dc bus capacitor C reaches a predetermined voltage, and then the power converter is connected to the ac power, for example, the predetermined voltage is a peak voltage of the ac power. Because the voltage of the direct current bus capacitor C reaches the peak voltage of the alternating current, larger impact current cannot be generated at the moment that the power converter is switched on the alternating current, and therefore damage to devices inside the power converter is avoided.

In this embodiment, the power converter may be applied to a charger of an electric vehicle, and the DC-DC circuit 200 of the power converter includes a primary side switching circuit 611, a transformer T, a secondary side high voltage switching circuit 612a, and a secondary side low voltage switching circuit 612 b. When the dc bus capacitor C is precharged, the dc power supplied from the low-voltage battery 810b of the electric vehicle charges the dc bus capacitor C, thereby preventing the dc power from being directly input to the dc bus capacitor C to generate a large impact current and damage the devices inside the power converter. Because the voltage of the low-voltage battery 810b is low, there is no danger of high-voltage electric shock, and therefore, the low-voltage battery 810b can be connected with the charger even when not being charged. When the direct current bus capacitor C needs to be precharged, the low-voltage battery 810b is directly used for precharging the direct current bus capacitor C, and the method is convenient and fast.

The first embodiment of the charger:

for convenience of understanding, a scene that the charger in the embodiment is applied to an electric vehicle is described below as an example, and the charger may be a vehicle-mounted charger.

Referring to fig. 8, the drawing is a schematic diagram of a charger according to an embodiment of the present application.

The charger 1000 can be applied to an electric vehicle, and the electric vehicle comprises a storage battery.

This charger 1000 includes: the device comprises a power factor correction PFC circuit 200, a direct current bus capacitor C, DC-DC circuit 610 and a charger controller 900.

The first end of the PFC circuit 200 is used for connecting an alternating current charging interface, the second end of the PFC circuit 200 is used for connecting the first end of the DC-DC circuit 610, and the DC bus capacitor C is connected in parallel to the second end of the PFC circuit 200.

The DC-DC circuit 610 is configured to convert the direct current output by the PFC circuit 200 under the control of the charger controller 900 and then charge the storage battery 810, and is further configured to convert the electric energy provided by the storage battery 810 and then charge the DC bus capacitor C under the control of the charger controller 900.

The charger controller 900 is configured to control the DC-DC circuit 610 to convert the electric energy provided by the battery 810 before the first end of the PFC circuit 200 is connected to the ac power, and then charge the DC bus capacitor C, and when the voltage of the DC bus capacitor C reaches a preset voltage, control the first end of the PFC circuit 200 to be connected to the ac power, so that the DC-DC circuit converts the DC power output by the PFC circuit 200 and then charges the battery 810. The power supply equipment is located on the ground, the charger is located on the electric automobile, and the storage battery is charged through the charger by utilizing the power supply equipment on the ground.

After the charger is connected to the power supply interface, the power supply device sends a charging start request message to the charger controller 900. After receiving the charging start request information, the charger controller 900 needs to precharge the dc bus capacitor C inside the charger. In this embodiment, a process of precharging the dc bus capacitor C inside the charger is described. The charger controller 900 controls the DC-DC circuit to convert the electric energy provided by the storage battery 810 of the electric vehicle and then charge the DC bus capacitor C.

When the voltage of the dc bus capacitor C reaches the preset voltage, the charger controller 900 sends feedback information of the charging start request information to the power supply apparatus.

After the power supply device receives the feedback information of the charging start request information sent by the charger controller 900, the switch between the power supply device and the power supply interface is closed, so that the power supply device supplies the alternating current to the charger through the power supply interface. Therefore, the situation that the device in the charger is damaged due to the fact that the alternating current is directly connected to the direct current bus capacitor C to generate large impact current is avoided.

In this embodiment, no new hardware is added to the charger. The charger comprises a power factor correction PFC circuit 200, a direct current bus capacitor C, DC-DC circuit 610 and a charger controller 900. Before the charger is connected with a power supply interface, the charger controller 900 controls the DC-DC circuit 610 to charge the direct current provided by the storage battery 810 to the direct current bus capacitor C by using the existing hardware, so that hardware equipment such as a pre-charging circuit and the like is not required to be additionally arranged, the size of the charger is reduced, and the production cost of the charger is reduced.

After the power supply device connects the alternating current to the charger through the power supply interface, the charger charges the storage battery 810 of the electric vehicle with the electric energy provided by the power supply device.

Charger embodiment two:

referring to fig. 9, the drawing is a schematic diagram of another charger provided in the embodiment of the present application.

The charger provided by the embodiment corresponds to the case that the storage battery 810 comprises a high-voltage battery 810a and a low-voltage battery 810 b.

The charger controller 700 is specifically configured to control the DC-DC circuit 610 to convert the electric energy provided by the high-voltage battery 810a or the low-voltage battery 810b and then charge the DC bus capacitor C.

The DC-DC circuit of the charger includes a primary side switching circuit 611, a transformer T, a secondary side high voltage switching circuit 612a, and a secondary side low voltage switching circuit 612 b.

Referring to fig. 10, a schematic diagram of a DC-DC circuit according to an embodiment of the present application is shown.

The figure provides an implementation of a secondary low voltage switch circuit in a DC-DC circuit, and the secondary low voltage switch circuit 612b may include capacitors Cr2 and C2 and switching tubes S5, S6, S7 and S8.

Referring to fig. 11, a schematic diagram of another DC-DC circuit provided in an embodiment of the application is shown.

The figure provides another implementation of the secondary side low voltage switch circuit in the DC-DC circuit, and the secondary side low voltage switch circuit 612b may include an inductor L1, capacitors C4 and C5, and switching tubes S9, S10, S11, S12, S13 and S14.

A first terminal of the primary side switching circuit 611 is connected to a second terminal of the PFC circuit 200.

The second terminal of the primary side switching circuit 611 is connected to the primary side winding of the transformer T.

The first secondary winding of the transformer T is connected to a first terminal of the secondary high-voltage switching circuit 612a, and a second terminal of the secondary high-voltage switching circuit 612a is used for charging the high-voltage battery 810 a.

The second secondary winding of the transformer T is connected to a first terminal of the secondary low voltage switch circuit 612b, and a second terminal of the secondary low voltage switch circuit 612b is used to charge the low voltage battery 810 b.

The controller T is specifically configured to control the secondary low-voltage switch circuit 612 to supply the energy of the low-voltage battery 810a to the second secondary winding of the transformer T, so that the DC-DC circuit 610 converts the electric energy supplied by the low-voltage battery 810a and charges the DC bus capacitor C.

Since the voltage of the high-voltage battery 810a of the electric vehicle is high, if the high-voltage battery 810a is always connected to the secondary high-voltage switch circuit 612a, a high-voltage electric shock safety accident may occur. Therefore, when the high-voltage battery 810a is not charged, the connection between the high-voltage battery 810a and the secondary high-voltage switch circuit 612a is disconnected as much as possible.

In the embodiment of the present application, the low-voltage battery 810b of the electric vehicle is used as an example to perform the pre-charging for the dc bus capacitor C.

In one possible embodiment, after the charger receives the charging start request message sent by the power supply device, the charger controller 900 controls the secondary low-voltage switch circuit 612b to input the dc power provided by the low-voltage battery 810b to the second secondary winding of the transformer T, and the dc power is provided to the first end of the primary switch circuit 611 through the primary winding of the transformer T, and the charger controller 900 controls the primary switch circuit 611 to charge the dc bus capacitor C.

When the voltage of the dc bus capacitor C reaches the preset voltage, the charger controller 900 controls the primary side switching circuit 611 to input the dc power provided by the PFC circuit 200 to the primary side winding of the transformer T, and inputs the dc power to the first end of the secondary low voltage switching circuit 612b through the second secondary side winding of the transformer T, and controls the secondary low voltage switching circuit 612b to charge the dc power output by the PFC circuit 200 to the low voltage battery 810 b.

The charger controller 900 may also control the primary side switching circuit 611 and the secondary side high voltage switching circuit 612a to charge the high voltage battery 810 a.

When the high-voltage battery 810a and the low-voltage battery 810b of the electric vehicle are charged, the high-voltage battery 810a and the low-voltage battery 810b can be charged simultaneously; or the high-voltage battery 810a may be charged first, and then the low-voltage battery 810b may be charged; alternatively, the low voltage battery 810b may be charged first, and then the high voltage battery 810a may be charged.

In addition, when the charger is used for charging the high-voltage battery 810a and/or the low-voltage battery 810b of the electric vehicle, certain electromagnetic interference is generated, and the charging quality is reduced. Therefore, in all the above embodiments, the EMC circuit 100 may be further included, that is, the first end of the PFC circuit 200 is connected to the EMC circuit 100, so as to reduce electromagnetic interference and improve charging quality.

Charging system embodiment:

based on the charger provided by the above embodiment, the embodiment of the application further provides a charging system, which is described in detail below with reference to the accompanying drawings.

Referring to fig. 12, the figure is a schematic view of a charging system provided in an embodiment of the present application.

This charging system includes: charger 1000, and power supply unit 2000.

The power supply device 2000 is configured to send charging start request information to the charger controller 900 before supplying electric power to the charger 1000.

The charger controller 900 includes a dc bus capacitor C for energy storage and filtering, and the charger 1000 is configured to send feedback information of the charging start request information to the power supply device 2000 when the voltage of the dc bus capacitor C reaches a preset voltage.

The power supply device 2000 is further configured to provide electric energy to the charger 1000 after receiving the feedback information.

The charger of the charging system may be any one of the charger embodiments i or 1000.

Referring to fig. 13, the figure is a schematic view of another charging system provided in the embodiment of the present application.

The operation is described below with reference to the hardware diagram of fig. 12 and the flowchart of fig. 13.

The electric vehicle 4000 charges a high-voltage battery and/or a low-voltage battery by using a charger, and comprises the following steps:

step 1: and the power supply equipment sends charging starting request information to the charger.

When the charger 1000 is inserted into the charging receptacle of the power supply interface 3000 through the charging plug, the power supply apparatus 2000 detects that the charger 1000 is connected to the power supply interface 3000, the power supply apparatus 2000 generates a connection confirmation signal (CC), and uses the CC signal as the charging start request information, and the power supply apparatus 2000 transmits the charging start request information to the charger 1000 through communication between the power supply control apparatus and the vehicle control apparatus.

Step 2: the charger controller controls the DC-DC circuit to convert the electric energy provided by the low-voltage battery of the electric automobile and then charge the direct-current bus capacitor.

Through communication between the power supply control device and the vehicle control device, after the charger 1000 receives the charging start request information sent by the power supply equipment 2000, the charger controller controls the DC-DC circuit to convert the electric energy provided by the low-voltage battery of the electric vehicle 4000 and charge the DC bus capacitor C. A new hardware circuit does not need to be added in the charger 1000, and the direct-current bus capacitor C is precharged through the charger controller, so that the size of the charger 1000 is reduced, and the production cost of the charger 1000 is reduced.

And step 3: the charger controller judges whether the voltage of the direct current bus capacitor reaches a preset voltage or not; if yes, executing step 4; if not, executing the step 2.

The charger controller determines the voltage of the dc bus capacitor C, and if the voltage of the dc bus capacitor C reaches a preset voltage, the charger 1000 generates a Control Pilot signal (CP) and sends the CP signal to the power supply device 2000 as feedback information of the charging start request information.

And if the voltage of the direct-current bus capacitor C does not reach the preset voltage, the charger controller continuously controls the DC-DC circuit to charge the direct-current bus capacitor C with the energy provided by the low-voltage battery.

And 4, step 4: the charger controller transmits feedback information of the charging start request information to the power supply device.

The charger controller transmits feedback information of the charge start request information to the power supply apparatus 2000 through communication between the vehicle control device and the power supply control device.

And 5: the power supply apparatus receives feedback information on the charge start request information, and controls the switch K1 and the switch K2 to be closed.

After the power supply device 2000 receives the feedback information, it indicates that the voltage of the dc bus capacitor C of the charger 1000 has reached the preset voltage, and then the switch K1 and the switch K2 are closed to start charging the charger. Therefore, the situation that the device in the charger is damaged due to the fact that the alternating current is directly connected to the direct current bus capacitor C to generate large impact current is avoided.

In this embodiment, when the charger 1000 needs to be charged, the power supply device 2000 sends charging start request information to the charger controller; after the charger controller receives the charging starting request information, the charger controller controls the DC-DC circuit to convert the electric energy provided by the low-voltage battery and then charge the direct-current bus capacitor C; when the charger controller determines that the voltage of the dc bus capacitor C reaches the preset voltage, it sends feedback information to the power supply device 2000; after receiving the feedback information, the power supply device 2000 controls the internal switches K1 and K2 to be closed, and provides electric energy to the charger 1000 through the power supply interface 3000. By using the charging system, when the electric vehicle 4000 charges the electric vehicle 4000 by using the charger 1000, new hardware does not need to be added in the charger 1000 of the electric vehicle 4000. The direct-current bus capacitor C is precharged by existing hardware of the charger 1000 under the control of the charger controller, hardware devices such as a precharge circuit and the like are not required to be additionally added, the size of the charger 1000 is reduced, and the production cost of the charger 1000 is reduced.

The method comprises the following steps:

referring to fig. 14, a flowchart of a precharge method according to an embodiment of the present application is shown.

The pre-charging method is applied to a first device, the first device comprises a power converter and a storage battery, the power converter comprises a direct current bus capacitor for energy storage and filtering, and the method comprises the following steps:

step 1401: and receiving charging starting request information sent by the power supply equipment.

Step 1402: and responding to the charging starting request information, and charging the direct current bus capacitor by using the electric energy provided by the storage battery.

Step 1403: and when the voltage of the direct current bus capacitor reaches the preset voltage, sending feedback information of the charging starting request information to the power supply equipment so that the power supply equipment provides electric energy for the charger through the power supply interface.

In this embodiment, the first device including the power converter and the battery is controlled by the method, and the pre-charging of the dc bus capacitance can be completed by using the existing hardware device in the power converter before the power converter switches on the ac without adding additional new hardware in the power converter. Therefore, hardware devices such as a pre-charging circuit and the like do not need to be additionally arranged, the size of the power converter is reduced, and the generation cost of the power converter is reduced. When the voltage of the direct current bus capacitor reaches the preset voltage, feedback information of the charging starting request information is sent to the power supply equipment, and the power supply equipment provides electric energy for the power converter through the power supply interface, so that the situation that the device in the PFC circuit is damaged due to the fact that the alternating current is directly connected to the direct current bus capacitor to generate large impact current is avoided.

It should be understood that in the present application, "at least one" means one or more, "a plurality" means two or more. "and/or" for describing an association relationship of associated objects, indicating that there may be three relationships, e.g., "a and/or B" may indicate: only A, only B and both A and B are present, wherein A and B may be singular or plural. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship. "at least one of the following" or similar expressions refer to any combination of these items, including any combination of single item(s) or plural items. For example, at least one (one) of a, b, or c, may represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", wherein a, b, c may be single or plural.

The foregoing is merely a preferred embodiment of the present application and is not intended to limit the present application in any way. Although the present application has been described with reference to the preferred embodiments, it is not intended to limit the present application. Those skilled in the art can now make numerous possible variations and modifications to the disclosed embodiments, or modify equivalent embodiments, using the methods and techniques disclosed above, without departing from the scope of the claimed embodiments. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present application still fall within the protection scope of the technical solution of the present application without departing from the content of the technical solution of the present application.