Torque ripple cancellation algorithm involving supply voltage limit constraint

• US 10,135,368 B2
• Filed: 10/01/2016
• Issued: 11/20/2018
• Est. Priority Date: 10/01/2016
• Status: Active Grant

• Current Assignee: Steering Solutions IP Holding Corporation (Nexteer Automotive Group Ltd.)
• Original Assignee: Steering Solutions IP Holding Corporation (Nexteer Automotive Group Ltd.)
• Inventors: Ballal, Siddharth, Pramod, Prerit, Kleinau, Julie A.
• Primary Examiner(s): Ismail, Shawki S
• Assistant Examiner(s): Imtiaz, Zoheb
• Application Number:
  US15/283,340
• Publication Number:
  US 20180097461A1
• Time in Patent Office: 780 Days
• CPC Class Codes: H02P 21/22 Current control, e.g. using a current control loop
• CPC Class Codes: H02P 6/10 Arrangements for controlling torque ripple, e.g. providing reduced torque ripple

Abstract

A system for reducing a torque ripple cancellation command is provided and includes a current regulator that provides motor voltage commands to a motor, and a torque ripple cancellation module that generates a torque ripple cancellation command based on input currents to the current regulator. A ramp-down command generator module that provides a ramp-down command to the torque ripple cancellation module is also provided. The ramp-down command is based on a voltage saturation indicator, and a voltage saturation indicator generator that generates a voltage saturation indicator signal. The voltage saturation indicator signal is based on a supply voltage signal and a motor voltage command.

Claims

1. A system for reducing a torque ripple cancellation command, the system comprising:

a current regulator that provides motor voltage commands to a motor;

a torque ripple cancellation module that generates a torque ripple cancellation command based on input currents to the current regulator;

a ramp-down command generator module that provides a ramp-down command to the torque ripple cancellation module, the ramp-down command is based on a voltage saturation indicator; and

a voltage saturation indicator generation module that generates a voltage saturation indicator signal, the voltage saturation indicator is based on a supply voltage signal and a motor voltage command;

wherein the ramp-down command is dependent on a first threshold and a second threshold and the ramp-down scale factor is linearly reduced as a function of a voltage saturation indicator signal.

2. The system of claim 1, the voltage saturation indicator is based on feedforward voltage magnitude generated by a motor reference command generator.

3. The system of claim 2, the feedforward voltage magnitude is calculated according to a square root of a sum of a first square of the d-axis feedforward voltage and a second square of the q-axis feedforward voltage.

4. The system of claim 1, the voltage saturation indicator is a final modulation index output of the current regulator.

5. A method for reducing a torque ripple cancellation command, the method comprising:

providing motor voltage commands to a motor;

generating a torque ripple cancellation command based on input currents;

providing a ramp-down command to the torque ripple cancellation module, the ramp-down command is based on a voltage saturation indicator and a motor voltage command; and

providing a voltage saturation indicator signal, the voltage saturation indicator signal is based on a supply voltage signal and a motor voltage command;

wherein the ramp-down command is dependent on a first threshold and a second threshold and the ramp-down scale factor is linearly reduced as a function of a voltage saturation indicator signal.

6. The method of claim 5, the voltage saturation indicator is based on a feedforward voltage magnitude.

7. The method of claim 6, the feedforward voltage magnitude is calculated according to a square root of a sum of a first square of the d-axis feed forward voltage and a second square of the q-axis feedforward voltage.

8. The method of claim 5, the voltage saturation indicator is based on the final modulation index signal or the final voltage output of the current regulator.