Motor controller

Patent metadata

Field	Value
Publication number	US-11770094-B2
Application number	US-202117218567-A
Country	US
Kind code	B2
Filing date	Mar 31, 2021
Priority date	Apr 2, 2020
Publication date	Sep 26, 2023
Grant date	Sep 26, 2023

Abstract

A motor controller includes individual drive circuits, a plurality of energization systems, and a processing circuit that outputs a plurality of individual control signals. The processing circuit executes a first calculation process, a second calculation process, a third calculation process, and a fourth calculation process for each of the energization systems. The first calculation process is a process of calculating individual current command values. The second calculation process is a process of calculating the estimated temperatures of protection targets. The third calculation process is a process of calculating individual limit values. The fourth calculation process is a process of calculating the individual control signals based on the individual current command values that are limited by the individual limit values. The processing circuit calculates the estimated temperatures of the protection targets where current of a target system flows.

First claim

What is claimed is:

1. A motor controller that controls a motor including a plurality of coil groups, comprising:
individual drive circuits corresponding to the coil groups, respectively;
a plurality of energization systems configured to supply drive electric power to the corresponding coil groups; and
at least one processing circuit configured to output a plurality of individual control signals that control operation of the individual drive circuits, respectively, wherein:
the processing circuit is configured to execute a first calculation process, a second calculation process, a third calculation process, and a fourth calculation process for each of the energization systems;
the first calculation process is a process of calculating individual current command values that are target values of current supplied to the coil groups;
the second calculation process is a process of calculating estimated temperatures of protection targets where the current of the energization systems flows;
the third calculation process is a process of calculating individual limit values that are upper limits of the individual current command values based on the estimated temperatures;
the fourth calculation process is a process of calculating the individual control signals based on the individual current command values that are limited by the individual limit values; and
the processing circuit is configured to calculate, in the second calculation process, the estimated temperatures of the protection targets where current of a target system flows, based on a reference temperature detected by a temperature sensor provided in the motor controller, an active change temperature attributed to energization to the target system, and a passive change temperature attributed to energization to another system, the target system being the energization system that causes current to flow to the protection targets that are subjected to calculation of the estimated temperature, the other system being the energization system other than the target system.

2. The motor controller according to claim 1 , wherein the processing circuit is configured to calculate, in the second calculation process, a sum of the reference temperature in a present calculation cycle, the active change temperature in the present calculation cycle, and the passive change temperature in the present calculation cycle as the estimated temperatures of the protection targets where the current of the target system flows.

3. The motor controller according to claim 1 , wherein the processing circuit is configured to calculate, in the second calculation process, the active change temperature in the present calculation cycle by using subsequent Expression (1) and calculate the passive change temperature in the present calculation cycle by using subsequent Expression (2):

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T
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eax
k

=

(

1
⁢

x
k
2

×
K
⁢

ax

-

Δ
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T
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eax

k
-
1

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(

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τ
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Δ
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k
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Expression
⁢

(
1
)

where Ix is a current flowing through the target system,
Kax is an active change gain set in accordance with the protection targets,
τax is a time constant of an active change delay filter that is set in accordance with the protection targets,
t is a time interval between the calculation cycles, and
ΔTeax k-1 is the active change temperature in a calculation cycle that is one cycle before the present calculation cycle; and

Δ
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T
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k

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T

Assignees

• Jtekt Corp

Inventors

• Niwa Tomohiro
• Honda Junya
• Maeda Hiroki

Classifications

• H02P29/60 Primary

  Controlling or determining the temperature of the motor or of the drive (H02P29/02 takes precedence) · CPC title

• B62D5/0463

  calculating assisting torque from the motor based on driver input · CPC title

• B62D5/0496

  by using a temperature sensor · CPC title

• H02P23/14

  Estimation or adaptation of motor parameters, e.g. rotor time constant, flux, speed, current or voltage · CPC title

• H02P25/22

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