Electric power control unit

Patent metadata

Field	Value
Publication number	US-10833623-B2
Application number	US-201816216023-A
Country	US
Kind code	B2
Filing date	Dec 11, 2018
Priority date	Dec 20, 2017
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

An electric power control unit configured to control drive power of a three-phase alternating current to be supplied to an electric motor may include: an inverter configured to convert a direct current to the three-phase alternating current; first and second current sensors, each of which is configured to measure a first-phase current in the three-phase alternating current; third and fourth current sensors, each of which is configured to measure a second-phase current in the three-phase alternating current; and a controller configured to control the inverter, and under a condition in which the first current sensor fails, when measured values of the second, the third, and the fourth current sensors do not coincide with each other while the inverter is shut down, the controller may stop to further supply the drive power to the electric motor.

First claim

What is claimed is:

1. An electric power control unit configured to control drive power of a three-phase alternating current to be supplied to an electric motor, the electric power control unit comprising:
an inverter configured to convert a direct current to the three-phase alternating current;
first and second current sensors, each of which is configured to measure a first-phase current in the three-phase alternating current;
third and fourth current sensors, each of which is configured to measure a second-phase current in the three-phase alternating current; and
a controller configured to control the inverter,
wherein
under a condition in which the first current sensor fails, when measured values of the second, the third, and the fourth current sensors do not coincide with each other while the inverter is shut down, the controller stops to further supply the drive power to the electric motor.

2. The electric power control unit of claim 1 , wherein
when the measured values of the second, the third, and the fourth current sensors coincide with each other while the inverter is shut down, the controller continues supply of the drive power to the electric motor.

3. The electric power control unit of claim 1 , wherein the first current sensor is provided with a self-diagnostic function.

4. An electric power control unit configured to control drive power of a three-phase alternating current to be supplied to an electric motor, the electric power control unit comprising:
an inverter configured to convert a direct current to the three-phase alternating current;
first and second current sensors, each of which is configured to measure a first-phase current in the three-phase alternating current;
third and fourth current sensors, each of which is configured to measure a second-phase current in the three-phase alternating current;
a fifth current sensor configured to measure a third-phase current in the three-phase alternating current; and
a controller configured to control the inverter,
wherein
under a condition in which the fifth current sensor fails, when measured values of the first and the second current sensors do not coincide with each other or measured values of the third and the fourth current sensors do not coincide with each other, the controller stops to further supply the drive power to the electric motor.

5. The electric power control unit of claim 4 , wherein
when the measured values of the first and the second current sensors coincide with each other and the measured values of the third and the fourth current sensors coincide with each other, the controller continues supply of the drive power to the electric motor.

6. An electric power control unit configured to control drive power of a three-phase alternating current to be supplied to an electric motor, the electric power control unit comprising:
an inverter configured to convert a direct current to the three-phase alternating current;
first and second current sensors, each of which is configured to measure a first-phase current in the three-phase alternating current;
third and fourth current sensors, each of which is configured to measure a second-phase current in the three-phase alternating current;
a fifth current sensor configured to measure a third-phase current in the three-phase alternating current; and
a controller configured to control the inverter,
wherein
under a condition in which the first current sensor fails, when measured values of the second, the third, and the fourth current sensors do not coincide with each other while the inverter is shut down, the controller stops to further supply the drive power to the electric motor.

7. The electric power control unit of claim 6 , wherein
when the measured values of the second, the third, and the fourth current sensors coincide with each other while the inverter is shut down, the controller continues supply of the drive power to the electric motor.

Assignees

• Denso Corp

Inventors

• Nakayama Wataru

Classifications

• H02P29/024 Primary

  Detecting a fault condition, e.g. short circuit, locked rotor, open circuit or loss of load · CPC title

• G01R35/02

  of auxiliary devices, e.g. of instrument transformers according to prescribed transformation ratio, phase angle, or wattage rating · CPC title

• G01R31/42

  AC power supplies · CPC title

• G01R15/202

  using Hall-effect devices (Hall elements in arrangements for measuring electrical power G01R21/08) · CPC title

• H02P29/032

  Preventing damage to the motor, e.g. setting individual current limits for different drive conditions · CPC title