Control method for semi-centralized open winding multi-motor drive system

Patent metadata

Field	Value
Publication number	US-12362687-B2
Application number	US-202318550652-A
Country	US
Kind code	B2
Filing date	Apr 12, 2023
Priority date	Sep 19, 2022
Publication date	Jul 15, 2025
Grant date	Jul 15, 2025

Abstract

A control method for a semi-centralized open winding multi-motor drive system includes: first, measuring current, voltage and position signal, computing system thrust by a velocity loop; then, distributing the thrust to each motor, converting the thrust into q axis current, computing dq axis voltages required for each motor by a current loop, and transforming the voltage demand to abc coordinate system through coordinate transformation; subsequently, modulating the voltage of each motor into a duty ratio instruction to judge whether the motor is in an over-modulated operating area, and performing over-modulation processing on the voltage in the over-modulated area; and finally, distributing the duty ratio instructions to independent and shared inverters. The control method of the present disclosure can reduce the hardware cost and improve the safety and reliability of the system.

First claim

What is claimed is:

1. A control method for a semi-centralized open winding multi-motor drive system, wherein the drive system is composed of N motors (N>0), one side of each rotor winding is respectively connected to an independent inverter, the other sides of all rotor windings are connected to a shared inverter together, and all rotors are rigidly connected;
the control method comprises the following steps:
step 1: distributing a q axis current instruction i* q_x to a motor according to a thrust demand F* e :

i

q
⁢
_
⁢
x

*

=

τ
s

⁢

F
e
*

3
⁢
N
⁢
π
⁢

ψ

f
⁢
1

wherein ψ ƒ1 represents a permanent flux linkage of the motor, τ s represents a polar distance of the same polarity between linear motors, and N represents the number of motors;
step 2: computing a dq0 axis voltage required for each motor:
first, computing a dq axis voltage using a proportional integral (PI) regulator:

{

u

d
⁢
_
⁢
x

=

k

p
⁢
_
⁢
d

⁢
_x

(

i

d
⁢
_
⁢
x

*

-

i

d
⁢
_
⁢
x

)

+

k

i_d
⁢

_
⁢
x

⁢

∫

(

i

d
⁢
_
⁢
x

*

-

i

d
⁢
_
⁢
x

)

⁢
dt

u

d
⁢
_
⁢
x

=

k

p
⁢
_
⁢
q

⁢
_x

⁢

(

i

q
⁢
_
⁢
x

*

-

i

q
⁢
_
⁢
x

)

+

k

i_q
⁢

_
⁢
x

⁢

Assignees

• Univ Southeast

Inventors

• Wang Wei
• Tian Weijie
• Cheng Ming

Classifications

• H02P27/06

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

• H02P21/141

  Flux estimation · CPC title

• H02P21/22

  Current control, e.g. using a current control loop · CPC title

• H02P5/52

  additionally providing control of relative angular displacement · CPC title

• H02P5/46

  for speed regulation of two or more dynamo-electric motors in relation to one another · CPC title