Power converter, power conversion system, and power conversion method

1. A power converter, wherein one side of the power converter is connected to a power grid equipment, the other side of the power converter is connected to an energy storage device located inside a vehicle, and the power grid equipment supplies power to the energy storage device through the power converter, the power converter comprising:

a control circuit;

a power conversion circuit;

a first converter; and

a second converter,

wherein:

the control circuit is configured to:

receive a second electric energy supplied to the control circuit from the power grid equipment through the second converter, and

output a fourth control signal to control the power conversion circuit to work after being powered on;

the power conversion circuit is configured to receive the fourth control signal and perform power conversion between the energy storage device and the power grid equipment according to the fourth control signal;

the first converter is configured to be in a working state after taking electricity from the power conversion circuit, down-convert an electric energy output from the power conversion circuit into a ninth electric energy in response to a fifth control signal, and supply power to the control circuit with the ninth electric energy; and

the control circuit is further configured to select the second electrical energy or the ninth electrical energy as the power supply of the control circuit based on a competitive power supply mode.

2. The power converter according to claim 1 , wherein the second converter is configured to down-convert a fifth electric energy input by the power grid equipment into the second electric energy.

3. The power converter according to claim 2 , wherein the power conversion circuit is further configured to convert the fifth electrical energy into an eighth electrical energy in response to the fourth control signal, wherein the fifth electrical energy is alternating current, and the eighth electrical energy is direct current and configured to supply power to the energy storage device.

4. The power converter according to claim 3 , wherein the control circuit is further configured to send the fifth control signal to the first converter after being powered on with the second electric energy.

5. The power converter according to claim 4 , wherein:

the control circuit is further configured to send a sixth control signal to the first converter after being powered on with the second electric energy or the ninth electric energy; and

the first converter is further configured to stop working in response to the sixth control signal.

6. The power converter according to claim 1 , further comprising:

a first diode, of which a positive pole is electrically connected with the first converter, and a negative pole is electrically connected with the control circuit, wherein the first converter is further configured to power the control circuit through the first diode; and

a second diode, of which a positive pole is electrically connected with the second converter, and a negative pole is electrically connected with the negative pole of the first diode, wherein the second converter is further configured to power the control circuit through the second diode.

7. A power conversion system comprising:

the power converter according to claim 1 ;

the power grid equipment electrically connected with the power converter and configured to output electric energy; and

the energy storage device electrically connected with the power converter and configured to output electric energy.

8. The power converter according to claim 1 , wherein:

the control circuit is further configured to select one of the second electrical energy and the ninth electrical energy with a higher voltage as the power supply of the control circuit.

9. A power conversion method, comprising:

receiving, by a control circuit, a second electric energy supplied to the control circuit from a power grid equipment through a second converter;

outputting, by the control circuit, a fourth control signal to control a power conversion circuit connected between an energy storage device and the power grid equipment to work after being powered on;

receiving, by the power conversion circuit, the fourth control signal and performing power conversion between the energy storage device and the power grid equipment according to the fourth control signal;

being, by a first converter, in a working state after taking electricity from the power conversion circuit, down-converting an electric energy output from the power conversion circuit into a ninth electric energy in response to a fifth control signal output from the control circuit, and supplying power to the control circuit with the ninth electric energy; and

selecting, by the control circuit, the second electrical energy or the ninth electrical energy as the power supply of the control circuit based on a competitive power supply mode.

10. The power conversion method according to claim 9 , further comprising:

down-converting, by the second converter, a fifth electric energy input by the power grid equipment into the second electric energy.

11. The power conversion method according to claim 10 , wherein the performing power conversion between the energy storage device and the power grid equipment according to the fourth control signal comprises: converting the fifth electrical energy into an eighth electrical energy in response to the fourth control signal, wherein the fifth electrical energy is alternating current, and the eighth electrical energy is direct current and configured to supply power to the energy storage device.

12. The power conversion method according to claim 11 , further comprising:

sending, by the control circuit, the fifth control signal to the first converter after being powered on with the second electric energy.

13. The power conversion method according to claim 12 , further comprising:

sending, by the control circuit, a sixth control signal to the first converter after being powered on with the second electric energy or the ninth electric energy; and

stopping the work of the first converter in response to the sixth control signal.

14. The power conversion method according to claim 9 , further comprising:

powering the control circuit by the first converter through a first diode; and

powering the control circuit by the second converter through a second diode.

15. The power conversion method according to claim 9 , wherein the selecting, by the control circuit, the second electrical energy or the ninth electrical energy as the power supply of the control circuit based on a competitive power supply mode comprises:

selecting, by the control circuit, one of the second electrical energy and the ninth electrical energy with a higher voltage as the power supply of the control circuit.