Distributed battery, battery control method, and electric vehicle

Patent metadata

Field	Value
Publication number	US-11322936-B2
Application number	US-201916672064-A
Country	US
Kind code	B2
Filing date	Nov 1, 2019
Priority date	May 3, 2017
Publication date	May 3, 2022
Grant date	May 3, 2022

Abstract

Disclosed herein is a distributed battery pack power supply system, a charging control method, and a discharging control method, where a plurality of battery packs or battery groups is directly coupled in parallel or indirectly coupled in parallel as required using a charging/discharging circuit of the distributed battery pack power supply system and a corresponding control policy. A distributed battery includes a plurality of battery packs, and further includes a controller, a bidirectional voltage transformation circuit, a bypass circuit, a charging circuit, and a charging input end. Each battery pack corresponds to one bypass circuit and one bidirectional voltage transformation circuit.

First claim

What is claimed is:

1. A distributed battery pack power supply system, configured to get charged from a charging input end, and the distributed battery pack power supply system comprising:
a first battery pack, comprising:
a positive electrode; and
a negative electrode;

a charging circuit, comprising:
an input end coupled to the charging input end;
a first output end; and
a second output end;

a first bypass circuit, coupled between the first battery pack and the charging circuit, the first bypass circuit comprising:
a first connection point coupled to the positive electrode of the first battery pack;
a second connection point coupled the negative electrode of the first battery pack;
a third connection point coupled to the first output end of the charging circuit;
a fourth connection point coupled to the second output end of the charging circuit;
a first switching device configured to couple the first connection point and the third connection point to form a first circuit that is enabled or disabled; and
a second switching device configured to couple the second connection point and the fourth connection point to form a second circuit that is enabled or disabled;

a first bidirectional voltage transformation circuit, coupled between the first battery pack and the charging circuit, and the first bidirectional voltage transformation circuit comprising:
a fifth connection point coupled to the first connection point and the positive electrode of the first battery pack;
a sixth connection point coupled to the second connection point and the negative electrode of the first battery pack;
a seventh connection point coupled to the third connection point and the first output end; and
an eighth connection point coupled to the fourth connection point and the second output end; and

a controller coupled to the first battery pack, the first bidirectional voltage transformation circuit, the first bypass circuit, and the charging circuit,
wherein the controller is configured to control an on-off status of the first switching device, an on-off status of the second switching device, and a working status of the first bidirectional voltage transformation circuit based on a voltage of the first battery pack and a parameter of the first battery pack, and
wherein the first bidirectional voltage transformation circuit is configured to perform a bidirectional voltage transformation between the first battery pack and the charging circuit.

2. The distributed battery pack power supply system of claim 1 , wherein the first bidirectional voltage transformation circuit comprises a first switch, a second switch, a third switch, a fourth switch, a fifth switch, a sixth switch, and an inductor, wherein a first end of the first switch is coupled to the fifth connection point, wherein a first end of the second switch is coupled to the sixth connection point, wherein a first end of the fifth switch is coupled to the seventh connection point, wherein a first end of the sixth switch is coupled to the eighth connection point, wherein a second end of the first switch is coupled to a first end of the third switch and a first end of the inductor, wherein a second end of the fifth switch is coupled to a first end of the fourth switch and a second end of the inductor, and wherein a second end of the second switch, a second end of the third switch, a second end of the fourth switch, and a second end of the sixth switch are coupled to each other.

3. The distributed battery pack power supply system of claim 2 , further comprising:
a second battery pack, comprising:
a positive electrode; and
a negative electrode;

a second bypass circuit, coupled between the second battery pack and the charging circuit, the second bypass circuit comprising:
a ninth connection point coupled to the positive electrode of the second battery pack;
a tenth connection point coupled to the negative electrode of the second battery pack;
an eleventh connection point coupled to the first output end of the charging circuit;
a twelfth connection point coupled to the second output end of the charging circuit;
a third switching device configured to couple the ninth connection point and the eleventh connection point to form a third circuit that is enabled or disabled; and
a fourth switching device configured to couple the tenth connection point and the twelfth connection point to form a fourth circuit that is enabled or disabled; and

a second bidirectional voltage transformation circuit, coupled between the second battery pack and the charging circuit, and the second bidirectional voltage transformation circuit comprising:
a thirteenth connection point coupled to the ninth connection point and the positive electrode of the second battery pack;
a fourteenth connection point coupled to the tenth connection point and the negative electrode of the second battery pack;
a fifteenth connection point coupled to the eleventh connection point and the first output end; and
a sixteenth connection point coupled to the twelfth connection point and the second output end;

wherein the controller is coupled to the second battery pack, the second bidirectional voltage transformation circuit, and the second bypass circuit,
wherein the controller is configured to control an on-off status of the third switching device, an on-off status of the fourth switching device, and a working status of the second bidirectional voltage transformation circuit based on a voltage of the second battery pack and a parameter of the second battery pack, and
wherein the second bidirectional voltage transformation circuit is configured to perform a bidirectional voltage transformation between the second battery pack and the charging circuit.

4. The distributed battery pack power supply system of claim 3 , wherein the first battery pack and the second battery pack are of a same type, and the controller is further configured to:
determine a voltage difference between the first battery pack and the second battery pack;
control the first switching device and the second switching device in the first bypass circuit to be closed to enable the first circuit and the second circuit;
control the third switching device and the fourth switching device in the second bypass circuit to be closed to enable the third circuit and the fourth circuit when the voltage difference is less than or equal to a first threshold and the charging circuit is in a working state; and
control an output current of the charging circuit to be less than or equal to a sum of charging currents of the first battery pack and the second battery pack.

5. The distributed battery pack power supply system of claim 3 , wherein the first battery pack and the second battery pack are of a same type, and wherein the controller is further configured to:
determine a voltage difference between the first battery pack and the second battery pack during charging;
control the first switching device and the second switching device in the first bypass circuit to be closed to enable the first circuit and the second circuit, and control an output current of the charging circuit to be less than or equal to a charging current of the first battery pack to charge the first battery pack when the voltage difference is greater than a first threshold and the charging circuit is in a working state, wherein a voltage of the first battery pack is less than a voltage of the second battery pack; or
control the third switching device and the fourth switching device in the second bypass circuit to be closed to enable the third and the fourth circuit, and control the output current of the charging circuit to be less than or equal to a sum of charging currents of the first battery pack and the second battery pack when the voltage difference is less than a sec

Assignees

• Huawei Tech Co Ltd

Inventors

• Zhou Kui
• Huang Boning
• Tong Wenping

Classifications

• H02J7/50

  acting upon multiple batteries simultaneously or sequentially · CPC title

• H02J7/54 Primary

  Passive balancing, e.g. using resistors or parallel MOSFETs · CPC title

• H02J7/02

  for charging batteries from AC mains by converters · CPC title

• H02J7/865

  Battery or charger load switching, e.g. concurrent charging and load supply (H02J7/50 takes precedence) · CPC title

• H02M3/1582

  Buck-boost converters (H02M3/1584 takes precedence) · CPC title