Rotating machine control device and electric power steering device

Patent metadata

Field	Value
Publication number	US-12304577-B2
Application number	US-202118269682-A
Country	US
Kind code	B2
Filing date	Apr 16, 2021
Priority date	Apr 16, 2021
Publication date	May 20, 2025
Grant date	May 20, 2025

Abstract

A rotating machine control device comprises: a first inverter that applies an alternating-current voltage to three-phase windings of a first system included in a rotating machine, based on a first direct-current voltage that has been output from a direct-current power supply of the first system; a second inverter that applies an alternating-current voltage to three-phase windings of a second system included in the rotating machine, based on a second direct-current voltage that has been output from a direct-current power supply of the second system; a first controller; and a second controller, in that the first controller and the second controller each limit an own system voltage command related to a voltage to be applied to the three-phase windings of an own system by use of a direct-current voltage of an other system, in a case where a direct-current voltage of the own system is higher than the direct-current voltage of the other system, and also generate a value obtained by normalizing the own system voltage command by use of the direct-current voltage of the own system, as a command value to an inverter of the own system.

First claim

The invention claimed is:

1. A rotating machine control device comprising:
a first inverter that applies an alternating-current voltage to three-phase windings of a first system included in a rotating machine, based on a first direct-current voltage that has been output from a direct-current power supply of the first system;
a second inverter that applies an alternating-current voltage to three-phase windings of a second system included in the rotating machine, based on a second direct-current voltage that has been output from a direct-current power supply of the second system;
a first controller that generates a command value to the first inverter, based on a command value of the rotating machine, the first direct-current voltage, and the second direct-current voltage; and
a second controller that generates a command value to the second inverter, based on the command value of the rotating machine, the first direct-current voltage, and the second direct-current voltage, wherein
the first controller and the second controller each limit an own system voltage command related to a voltage to be applied to the three-phase windings of an own system by use of a direct-current voltage of an other system, in a case where a direct-current voltage of the own system is higher than the direct-current voltage of the other system, and also generate a value obtained by normalizing the own system voltage command by use of the direct-current voltage of the own system, as a command value to an inverter of the own system.

2. The rotating machine control device according to claim 1 , wherein
the first controller and the second controller each
calculate a zero-phase voltage of the own system, based on the direct-current voltage of the own system, and correct the own system voltage command of each phase, based on the zero-phase voltage of the own system.

3. The rotating machine control device according to claim 2 , wherein
the first controller and the second controller each calculate the zero-phase voltage of the own system for a minimum one of the own system voltage command to match a predetermined lower limit value based on the direct-current voltage of the own system.

4. The rotating machine control device according to claim 2 , wherein
the first controller and the second controller each
calculate the zero-phase voltage of the own system for a maximum one of the own system voltage command to match a predetermined upper limit value based on the direct-current voltage of the own system.

5. The rotating machine control device according to claim 1 , wherein
the first controller and the second controller each limit the own system voltage command, based on a voltage deviation, in a case where the direct-current voltage of the own system is higher than the direct-current voltage of the other system, the voltage deviation being a value obtained in such a manner that out of a direct-current part electric current of the first system that is an electric current of a direct-current part to flow into the first inverter and a direct-current part electric current of the second system that is an electric current of a direct-current part to flow into the second inverter, the direct-current part electric current of the own system is subtracted from the direct-current part electric current of the other system and a subtraction result is multiplied by a wiring resistance indicating a resistance of wiring through that the direct-current part electric current of the own system flows.

6. The rotating machine control device according to claim 5 , wherein
the first controller and the second controller each calculate the direct-current part electric current of the other system, based on the direct-current voltage of the other system.

7. The rotating machine control device according to claim 5 , wherein
the first controller and the second controller each calculate the direct-current part electric current of the other system, based on the direct-current voltage of the own system, the direct-current voltage of the other system, and a direct current of the own system.

8. The rotating machine control device according to claim 5 , further comprising
an electric current detector that detects electric currents that respectively flow through three-phase windings of each system, wherein
the first controller and the second controller each calculate a direct current of the own system, based on the electric currents that respectively flow through the three-phase windings of the own system that have been detected by the electric current detector.

9. The rotating machine control device according to claim 1 , wherein
the first controller comprises a first central processing unit (CPU),
the second controller comprises a second CPU,
the first CPU transmits the first direct-current voltage to the second CPU, and
the second CPU transmits the second direct-current voltage to the first CPU.

10. The rotating machine control device according to claim 1 , wherein
the first controller and the second controller each limit a voltage command on dq-axes, out of own system voltage commands, by use of the direct-current voltage of the other system, in a case where the direct-current voltage of the own system is higher than the direct-current voltage of the other system.

11. The rotating machine control device according to claim 1 , wherein
the first controller and the second controller each limit a magnitude of a voltage command vector on a stationary coordinate axis, out of own system voltage commands, to a value that the direct-current voltage of the other system is capable of outputting, in a case where the direct-current voltage of the own system is higher than the direct-current voltage of the other system.

12. An electric power steering device comprising:
the rotating machine control device of claim 1 ;
the rotating machine that assists steering in steering; and
a torque sensor that detects steering torque in the steering, wherein
the rotating machine control device controls the rotating machine with an assist command of the steering in accordance with the steering torque that has been detected by the torque sensor, as a command value of the rotating machine.

Assignees

• Mitsubishi Electric Corp

Inventors

• Tamaru Tomohiro
• Mori Tatsuya
• Fujimoto Chiaki

Classifications

• H02P27/08

  with pulse width modulation · CPC title

• H02P25/22 Primary

  Multiple windings; Windings for more than three phases · CPC title

• H02P21/22

  Current control, e.g. using a current control loop · CPC title

• B62D5/003

  Backup systems, e.g. for manual steering (B62D5/30 takes precedence) · CPC title

• B62D5/0484

  for reaction to failures, e.g. limp home · CPC title