Motor drive device

Patent metadata

Field	Value
Publication number	US-9310798-B2
Application number	US-201214385558-A
Country	US
Kind code	B2
Filing date	Mar 30, 2012
Priority date	Mar 30, 2012
Publication date	Apr 12, 2016
Grant date	Apr 12, 2016

Abstract

A motor drive device in embodiments includes: a motor drive unit that generates a current for driving a motor on a basis of a position command and a position detection value of the motor; a motor-coil ambient-temperature estimation unit that calculates a motor-coil ambient-temperature estimation value by correcting an output value of a temperature sensor provided in a peripheral portion of a motor coil of the motor by using a filter including both a phase-lead characteristic and a low-pass characteristic; a motor-coil increased-temperature estimation unit that calculates a motor-coil increased-temperature estimation value on a basis of the current; and a motor-coil protection unit that limits the current on a basis of the motor-coil ambient-temperature estimation value and the motor-coil increased-temperature estimation value.

First claim

The invention claimed is:

1. A motor drive device comprising:
a motor drive unit that generates a current for driving a motor on a basis of a position command and a position detection value of the motor;
a motor-coil ambient-temperature estimation unit that calculates a motor-coil ambient-temperature estimation value by correcting an output value of a temperature sensor provided in a peripheral portion of a motor coil of the motor by using a filter including both a phase-lead characteristic and a low-pass characteristic;
a motor-coil increased-temperature estimation unit that calculates a motor-coil increased-temperature estimation value on a basis of the current; and
a motor-coil protection unit that limits the current on a basis of the motor-coil ambient-temperature estimation value and the motor-coil increased-temperature estimation value, wherein
the motor-coil ambient-temperature estimation unit causes the filter to have the phase-lead characteristic when a temperature increase value calculated on a basis of an output value of the temperature sensor and its immediately previous output value is larger than a predetermined value, and causes the filter not to have the phase-lead characteristic when the temperature increase value is smaller than the predetermined value.

2. The motor drive device according to claim 1 , wherein the motor-coil ambient-temperature estimation unit determines a coefficient to be used for the phase-lead characteristic on a basis of a time-series pattern of an output value of the temperature sensor and a time-series pattern that is obtained by multiplying the time-series pattern of the output value by the low-pass characteristic when driving the motor with a predetermined acceleration/deceleration pattern.

3. The motor drive device according to claim 2 , wherein the motor-coil increased-temperature estimation unit calculates the motor-coil increased-temperature estimation value by correcting a value that is obtained by multiplying a square value of the current by a predetermined gain by using a low pass filter, and determines the gain on a basis of the motor-coil ambient-temperature estimation value obtained by using the determined coefficient and on a basis of time-series patterns of the output value of the temperature sensor and the current when driving the motor with the predetermined acceleration/deceleration pattern.

4. The motor drive device according to claim 1 , wherein the motor-coil increased-temperature estimation unit calculates the motor-coil increased-temperature estimation value by correcting a value that is obtained by multiplying a square value of the current by a predetermined gain by using a low pass filter, and determines the gain on a basis of time-series patterns of the output value of the temperature sensor and the current when driving the motor with a predetermined acceleration/deceleration pattern.

Assignees

• Nagata Yuichi
• Sano Shuya
• Sugie Hiroshi
• Mitsubishi Electric Corp

Inventors

• Nagata Yuichi
• Sano Shuya
• Sugie Hiroshi

Classifications

• G05B6/02

  electric · CPC title

• H02K11/0015

  Electricity · mapped topic

• G05B19/404 Primary

  characterised by control arrangements for compensation, e.g. for backlash, overshoot, tool offset, tool wear, temperature, machine construction errors, load, inertia (G05B19/19, G05B19/41 take precedence) · CPC title

• H02P29/0055

  Electricity · mapped topic

• H02K11/0047

  Electricity · mapped topic