MOTOR CONTROLLER FOR ELECTRIC VEHICLE

• US 20150180386A1
• Filed: 10/15/2012
• Published: 06/25/2015
• Est. Priority Date: 10/15/2012
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: Enoki, Keiichi, Iezawa, Masahiro, Ogawa, Yasufumi, Kobayashi, Hiroyuki, Mori, Nobuhide
• Granted Patent: US 9,641,107 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60L 15/20 for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
• CPC Class Codes: B60L 2240/12 Speed
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2270/145 Structure borne vibrations
• CPC Class Codes: H02P 6/10 Arrangements for controlling torque ripple, e.g. providing reduced torque ripple
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility

Abstract

A motor controller for an electric vehicle sufficiently reduces vibration components caused by torque ripples passing through a resonance frequency of a vehicle body. The motor controller includes motor torque setting means for generating a first torque command, based on vehicle information, rotation position detection means for detecting a rotation position of the motor, rotation speed calculation means for calculating a rotation speed from a rotation position signal, a high-pass filter that extracts an AC signal component of a rotation speed signal, and a resonance suppression gain circuit that outputs a resonance suppression signal. A signal in which the resonance suppression signal is added to or subtracted from the first torque command is used as a second torque command so as to perform drive control for the motor.

Claims

1-12. -12. (canceled)

13. A motor controller for an electric vehicle which uses a motor as a drive source, comprising:

motor torque setting means for generating a first torque command, based on vehicle information including an accelerator opening degree and a vehicle speed of the electric vehicle;

rotation position detection means for detecting a rotation position of the motor;

rotation speed calculation means for calculating a rotation speed from a rotation position signal detected by the rotation position detection means;

a high-pass filter that extracts an AC signal component of a rotation speed signal calculated by the rotation speed calculation means; and

a resonance suppression gain circuit that outputs a resonance suppression signal, based on an AC signal extracted by the high-pass filter,

wherein a signal in which the resonance suppression signal is added to or subtracted from the first torque command is used as a second torque command so as to perform a drive control for the motor.

14. The motor controller for an electric vehicle according to claim 13,

wherein the high-pass filter that extracts the AC signal component of the rotation speed serves as a primary or a secondary high-pass filter.

15. The motor controller for an electric vehicle according to claim 14,

wherein in the high-pass filter in which the high-pass filter that extracts the AC signal component of the rotation speed serves as the primary high-pass filter, the second torque command in which the resonance suppression signal is added to or subtracted from the first torque command is multiplied by a coefficient so that a steady-state error becomes zero between the first torque command and the second torque command.

16. The motor controller for an electric vehicle according to claim 14,

wherein in the high-pass filter in which the high-pass filter that extracts the AC signal component of the rotation speed serves as the secondary high-pass filter, a proportional gain G is applied to an output of the high-pass filter.

17. The motor controller for an electric vehicle according to claim 13, further comprising:

torque ripple model calculation means for outputting a torque ripple model signal from the first torque command and the rotation position signal; and

a torque ripple model compensation gain circuit that outputs a torque ripple model compensation signal, based on the torque ripple model signal,

wherein a signal in which the torque ripple model compensation signal and the resonance suppression signal are added to or subtracted from the first torque command is used as the second torque command so that current control means of the motor performs a process.

18. The motor controller for an electric vehicle according to claim 17,

wherein in the torque ripple model calculation means for outputting the torque ripple model signal from the first torque command and the rotation position signal, the maximum order number n of a torque ripple model which is used in calculating the torque ripple model signal is set so as to be smaller than a value calculated by 60 degrees/position detection error (electrical angle).

19. The motor controller for an electric vehicle according to claim 17,

wherein in the torque ripple model calculation means for outputting the torque ripple model signal from the first torque command and the rotation position signal, amplitude and a phase of the torque ripples based on a magnetic field analysis of the motor or a prior measurement result of a representative motor is set to an amplitude map and a phase map of the torque ripple model used in calculating the torque ripple model signal.

20. The motor controller for an electric vehicle according to claim 17,

wherein in the torque ripple model calculation means for outputting the torque ripple model signal from the first torque command and the rotation position signal, the torque ripples are measured by using a motor having no connection with vehicle characteristics, a torque meter, and a low-speed pulsation motor controlled to maintain a constant speed, and

wherein a map is created, based on the amplitude and the phase of the measured torque ripples.

21. The motor controller for an electric vehicle according to claim 17,

wherein a size of the torque ripple model compensation gain circuit can be changed depending on the rotation speed.

22. The motor controller for an electric vehicle according to claim 17, further comprising:

a band-pass filter whose center frequency is a frequency of the torque ripples which is determined in advance by a motor structure and an inverter driving method; and

a torque ripple error compensation gain circuit that outputs a torque ripple error compensation signal, based on a torque ripple frequency signal extracted from the band-pass filter,

wherein a signal in which the torque ripple model compensation signal, the torque ripple error compensation signal and the resonance suppression signal are added to or subtracted from the first torque command is used as the second torque command so that the current control means of the motor performs a process.

23. The motor controller for an electric vehicle according to claim 22,

wherein a setting value of the damping constant in the band-pass filter is set to 0.05 to 1.

24. The motor controller for an electric vehicle according to claim 22,

wherein a size of the torque ripple error compensation gain circuit can be changed depending on the rotation speed.