AC-rotary-machine control device and electric power-steering system provided with AC-rotary-machine control device

Patent metadata

Field	Value
Publication number	US-10116250-B2
Application number	US-201415307204-A
Country	US
Kind code	B2
Filing date	Jun 16, 2014
Priority date	Jun 16, 2014
Publication date	Oct 30, 2018
Grant date	Oct 30, 2018

Abstract

When there is an error between an actual resistance value of an AC rotary machine (ACRM) and an estimated resistance value estimated from a detected external temperature of the ACRM, the ACRM cannot be rotated smoothly. In view of this, provided are a control device for an ACRM and the like, including a resistance value estimation unit (10) configured to calculate an estimated resistance value (Rest) by adding to a basic estimated resistance value (Rest0), which is a value obtained by estimating a resistance value from a detected external temperature of the ACRM, an estimated resistance correction value (Radd), which is determined such that a range that can be taken by an error (ΔR) of the resistance value estimated in advance falls within a range of the error of the resistance value that enables the ACRM to be rotated smoothly.

First claim

The invention claimed is:

1. A controller for an AC rotary machine, which is configured to control the AC rotary machine based on an estimated resistance value of the AC rotary machine, the controller comprising:
a temperature detector configured to detect an external temperature of the AC rotary machine, and to output the detected external temperature;
a resistance value estimator to estimate, based on the detected external temperature, an actual resistance value of the AC rotary machine, which changes depending on temperature of the AC rotary machine, and to output the estimated resistance value; and
a voltage supply configured to apply a voltage to an AC rotary machine based on the estimated resistance value,
wherein the resistance value estimator calculates a basic estimated resistance value, which is a sum of a first resistance value defined as a fixed value and a second resistance value that is proportional to the detected external temperature, and to calculate the estimated resistance value by adding an estimated resistance correction value to the basic estimated resistance value,
wherein the estimated resistance correction value comprises a negative value having an absolute value that is larger than a difference between a lower limit value of a resistance value error allowable range and a deviation estimate, and is smaller than an absolute value of the deviation estimate,
wherein the deviation estimate is a value set in advance as a lower limit of a range that is taken by a deviation obtained by subtracting the basic estimated resistance value from the actual resistance value, and
wherein the resistance value error allowable range comprises a range of a resistance value error that enables the AC rotary machine to be rotated smoothly.

2. The controller for an AC rotary machine according to claim 1 , wherein the deviation estimate comprises a value that is based on a detection temperature for estimating the deviation, the detection temperature being obtained by extracting one or a plurality of points from a range that is taken by the detected external temperature.

3. The controller for an AC rotary machine according to claim 2 , wherein the deviation estimate is based on a range of an individual difference of the actual resistance value.

4. The controller for an AC rotary machine according to claim 2 , further comprising:
a calculator to calculate a phase of an alternating voltage of the AC rotary machine and voltages on two rotation axes of the AC rotary machine, which are based on the estimated resistance value; and
a current supply to apply the alternating voltage to the AC rotary machine based on the phase and the voltages on the two rotation axes.

5. The controller for an AC rotary machine according to claim 2 , wherein the deviation estimate is based on an upper limit or lower limit of a rotary machine temperature range for the deviation estimate, which is a range of temperature that is taken by temperature of the AC rotary machine at the detection temperature for estimating the deviation.

6. The controller for an AC rotary machine according to claim 5 , wherein the deviation estimate is based on a range of an individual difference of the actual resistance value.

7. The controller for an AC rotary machine according to claim 5 , further comprising:
a calculator configured to calculate a phase of an alternating voltage of the AC rotary machine and voltages on two rotation axes of the AC rotary machine, which are based on the estimated resistance value; and
a current supply to apply the alternating voltage to the AC rotary machine based on the phase and the voltages on the two rotation axes.

8. The controller for an AC rotary machine according to claim 1 , wherein the deviation estimate is based on a range of an individual difference of the actual resistance value.

9. The controller for an AC rotary machine according to claim 1 , further comprising:
a calculator to calculate a phase of an alternating voltage of the AC rotary machine and voltages on two rotation axes of the AC rotary machine, which are based on the estimated resistance value; and
a current supply to apply the alternating voltage to the AC rotary machine based on the phase and the voltages on the two rotation axes.

10. An electric power steering system, comprising the controller for the AC rotary machine of claim 1 , configured to generate a torque to be transmitted to a steering shaft.

11. A controller for an AC rotary machine, which is configured to control the AC rotary machine based on an estimated resistance value of the AC rotary machine, the controller comprising:
a temperature detector configured to detect an external temperature of the AC rotary machine, and to output the detected external temperature; and
a resistance value estimator to estimate, based on the detected external temperature, an actual resistance value of the AC rotary machine, which changes depending on temperature of the AC rotary machine, and to output the estimated resistance value; and
a voltage supply configured to apply a voltage to an AC rotary machine based on the estimated resistance value,
wherein the resistance value estimator calculates a basic estimated resistance value, which is a sum of a first resistance value defined as a fixed value and a second resistance value that is proportional to the detected external temperature, and to calculate the estimated resistance value by adding an estimated resistance correction value to the basic estimated resistance value,
wherein the estimated resistance correction value is a positive value having an absolute value that is larger than a difference between an upper limit value of a resistance value error allowable range and a deviation estimate, and is smaller than an absolute value of the deviation estimate,
wherein the deviation estimate comprises a value set in advance as an upper limit of a range that is taken by a deviation obtained by subtracting the basic estimated resistance value from the actual resistance value, and
wherein the resistance value error allowable range comprises a range of a resistance value error that enables the AC rotary machine to be rotated smoothly.

12. The controller for an AC rotary machine according to claim 11 , wherein the deviation estimate comprises a value that is based on a detection temperature for estimating the deviation, the detection temperature being obtained by extracting one or a plurality of points from a range that is taken by the detected external temperature.

13. The controller for an AC rotary machine according to claim 12 , wherein the deviation estimate is based on a range of an individual difference of the actual resistance value.

14. The controller for an AC rotary machine according to claim 12 , further comprising:
a calculator to calculate a phase of an alternating voltage of the AC rotary machine and voltages on two rotation axes of the AC rotary machine, which are based on the estimated resistance value; and
a current supply to apply the alternating voltage to the AC rotary machine based on the phase and the voltages on the two rotation axes.

15. The controller for an AC rotary machine according to claim 12 , wherein the deviation estimate is based on an upper limit or lower limit of a rotary machine temperature range for the deviation estimate, which is a range of temperature that is taken by temperature of the AC rotary machine at the detection temperature for estimating the deviation.

16. The controller for an AC rotary machine according to claim 15 , wherein the deviation estimate is based on a range of an individu

Assignees

• Mitsubishi Electric Corp

Inventors

• TSUCHIMOTO Yuya
• Kezobo Isao
• Kimpara Yoshihiko
• Nakajima Shunsuke

Classifications

• H02P29/64 Primary

  Controlling or determining the temperature of the winding · CPC title

• H02P6/14

  Electronic commutators · CPC title

• H02P21/13

  Observer control, e.g. using Luenberger observers or Kalman filters · CPC title

• H02P21/14

  Estimation or adaptation of machine parameters, e.g. flux, current or voltage · CPC title

• H02P27/06

  using DC to AC converters or inverters (H02P27/05 takes precedence) · CPC title