Voltage control method and apparatus, household device, computer storage medium, and computer program

Patent metadata

Field	Value
Publication number	US-12525875-B2
Application number	US-202218287390-A
Country	US
Kind code	B2
Filing date	Mar 25, 2022
Priority date	Apr 26, 2021
Publication date	Jan 13, 2026
Grant date	Jan 13, 2026

Abstract

A voltage control method includes obtaining two half-bus voltages at a direct current side of a three-level converter, overvoltage protection values of the two half-bus voltages, and a load voltage required by a load. One of the two half-bus voltages is configured to supply voltage to the load. The method further includes determining a voltage control strategy based on a relationship among the two half-bus voltages, the overvoltage protection values, and the load voltage. The voltage control strategy compensates for an output duty ratio of a switch of the three-level converter, such that the one of the two half-bus voltages is greater than or equal to the load voltage and each of the two half-bus voltages is smaller than or equal to a corresponding one of the overvoltage protection values. The method also includes performing voltage control on the two half-bus voltages based on the voltage control strategy.

First claim

What is claimed is:

1 . A voltage control method comprising:
obtaining two half-bus voltages at a direct current side of a three-level converter, overvoltage protection values of the two half-bus voltages, and a load voltage required by a load, one of the two half-bus voltages being configured to supply voltage to the load; determining a voltage control strategy based on a relationship among the two half-bus voltages, the overvoltage protection values, and the load voltage, the voltage control strategy being configured to compensate for an output duty ratio of a switch of the three-level converter, such that the one of the two half-bus voltages is greater than or equal to the load voltage and each of the two half-bus voltages is smaller than or equal to a corresponding one of the overvoltage protection values; and performing voltage control on the two half-bus voltages based on the voltage control strategy.

2 . The voltage control method according to claim 1 , wherein determining the voltage control strategy includes:
determining a compensation amount based on the relationship; and compensating for a current output duty ratio of the switch with the compensation amount.

3 . The voltage control method according to claim 2 , wherein determining the compensation amount includes:
determining a control amount for the two half-bus voltages based on the relationship; and obtaining the compensation amount by performing proportional integral (PI) control on the control amount.

4 . The voltage control method according to claim 3 , wherein determining the control amount includes:
obtaining a determination result by determining, in response to each of the two half-bus voltages being smaller than or equal to the corresponding one of the overvoltage protection values, a magnitude relationship between the one of the two half-bus voltages and the load voltage; and determining the control amount based on the determination result.

5 . The voltage control method according to claim 4 , wherein determining the control amount based on the determination result includes:
determining, in response to the one of the two half-bus voltages being smaller than the load voltage, the control amount be a difference value obtained by subtracting the one of the two half-bus voltages from the load voltage; and determining, in response to the one of the two half-bus voltages being greater than or equal to the load voltage required by the first load, the control amount to be zero.

6 . The voltage control method according to claim 4 , wherein determining the control amount further includes:
determining, in response to the one of the two half-bus voltages being smaller than or equal to the corresponding overvoltage protection value and another one of the two half-bus voltages being greater than the corresponding overvoltage protection value, the control amount to be a difference value obtained by subtracting the overvoltage protection value corresponding to the another one of the two half-bus voltages from the another one of the two half-bus voltages.

7 . The voltage control method according to claim 4 , wherein determining the control amount further includes:
determining, in response to the one of the two half-bus voltages being greater than the corresponding overvoltage protection value and another one of the two half-bus voltages being smaller than or equal to the corresponding overvoltage protection value, the control amount to be a difference value obtained by subtracting the one of the two half-bus voltages from the overvoltage protection value corresponding to the one of the two half-bus voltages.

8 . The voltage control method according to claim 4 , wherein determining the control amount further includes:
determining, in response to the two half-bus voltages being both greater than the corresponding overvoltage protection values, the control amount to be a difference value obtained by subtracting the one of the two half-bus voltages from another one of the two half-bus voltages.

9 . The voltage control method according to claim 1 , wherein the overvoltage protection values are smaller than or equal to a withstand voltage value of a capacitor at the direct current side of the three-level converter.

10 . A voltage control apparatus comprising:
a memory storing a computer program; and a processor configured to execute the program to:
obtain two half-bus voltages at a direct current side of a three-level converter, overvoltage protection values of the two half-bus voltages, and a load voltage required by a load, one of the two half-bus voltages being configured to supply voltage to the load;
determine a voltage control strategy based on a relationship among the two half-bus voltages, the overvoltage protection values, and the load voltage, the voltage control strategy being configured to compensate for an output duty ratio of a switch of the three-level converter, such that the one of the two half-bus voltages is greater than or equal to the load voltage and each of the two half-bus voltages is smaller than or equal to a corresponding one of the overvoltage protection values; and
perform voltage control on the two half-bus voltages based on the voltage control strategy.

11 . The voltage control apparatus according to claim 10 , wherein the processor is further configured to execute the program to:
determine a compensation amount based on the relationship; and compensate for a current output duty ratio of the switch with the compensation amount.

12 . The voltage control apparatus according to claim 11 , wherein the processor is further configured to execute the program to:
determine a control amount for the two half-bus voltages based on the relationship; and obtain the compensation amount by performing proportional integral (PI) control on the control amount.

13 . The voltage control apparatus according to claim 12 , wherein the processor is further configured to execute the program to:
obtain a determination result by determining, in response to each of the two half-bus voltages being smaller than or equal to the corresponding one of the overvoltage protection values, a magnitude relationship between the one of the two half-bus voltages and the load voltage; and determine the control amount based on the determination result.

14 . The voltage control apparatus according to claim 13 , wherein the processor is further configured to execute the program to:
determine, in response to the one of the two half-bus voltages being smaller than the load voltage, the control amount be a difference value obtained by subtracting the one of the two half-bus voltages from the load voltage; and determine, in response to the one of the two half-bus voltages being greater than or equal to the load voltage required by the first load, the control amount to be zero.

15 . The voltage control apparatus according to claim 13 , wherein the processor is further configured to execute the program to:
determine, in response to the one of the two half-bus voltages being smaller than or equal to the corresponding overvoltage protection value and another one of the two half-bus voltages being greater than the corresponding overvoltage protection value, the control amount to be a difference value obtained by subtracting the overvoltage protection value corresponding to the another one of the two half-bus voltages from the another one of the two half-bus voltages.

16 . The voltage control apparatus according to claim 13 , wherein the processor is further configured to execute the program to:
dete

Assignees

• Foshan Shunde Midea Electric Science And Tech Co Ltd
• Gd Midea Air Conditioning Equipment Co Ltd

Inventors

• Zhao Ming
• Huang Zhaobin
• Long Tan
• Wen Xianshi
• Wei Dong
• Huang Zhenghui

Classifications

• H02M7/06

  using discharge tubes without control electrode or semiconductor devices without control electrode · CPC title

• H02M1/32

  Means for protecting converters other than automatic disconnection · CPC title

• H02M7/125

  Avoiding or suppressing excessive transient voltages or currents · CPC title

• H02M1/12

  Arrangements for reducing harmonics from AC input or output · CPC title

• H02M7/217

  using semiconductor devices only · CPC title