Method and system for measuring flux-switching electric motor rotor angle on basis of linear hall sensors

Patent metadata

Field	Value
Publication number	US-12388337-B2
Application number	US-202118279391-A
Country	US
Kind code	B2
Filing date	Nov 29, 2021
Priority date	Apr 22, 2021
Publication date	Aug 12, 2025
Grant date	Aug 12, 2025

Abstract

Disclosed are a method and system for measuring a flux-switching electric motor rotor angle on the basis of linear Hall. The method comprises: firstly, selecting four linear Hall sensors and respectively mounting same in four slots of a stator; a first linear Hall sensor is mounted in any slot of the stator, and a second linear Hall sensor is spaced apart from the first linear Hall sensor by N 1 slots in a unified direction; N 1 is an even number, and N 1 ≠ks/(2 p ); a third linear Hall sensor is spaced apart from the first linear Hall sensor by N 2 slots; N 2 is an odd number, and N 2 =(2 k −1)s/(2 p ); and a fourth linear Hall sensor is spaced apart from the second linear Hall sensor by N 2 slots; and then calculating an electric motor rotor angle according to voltage signals of the four linear Hall sensors.

First claim

What is claimed is:

1. A method for measuring a flux-switching electric motor rotor angle on basis of linear Hall, a first linear Hall element, a second linear Hall element, a third linear Hall element and a fourth linear Hall element are mounted in sequence in slots of four stators of a flux-switching electric motor upon a principle that output signals between the first linear Hall element and the third linear Hall element are in phase and output signals between the second linear Hall element and the fourth linear Hall element are in phase, two sets of in-phase output signals are superimposed separately to obtain a pair of sinusoidal signals, a linear combination of the pair of sinusoidal signals is performed to obtain a pair of quadrature signals in a two-phase stationary coordinate system, and a closed-loop control is performed on the pair of quadrature signals in the two-phase stationary coordinate system according to an estimate of a rotor angle,
wherein an expression for the pair of sinusoidal signals obtained by superimposing the two sets of in-phase output signals is

{

U
A

=

U
1

+

U
3

=

U
m

⁢
cos
⁢
θ

+

ε
⁡
(

3
⁢
θ

)

U
B

=

U
2

+

U
4

=

U
m

⁢
cos
⁢

(

θ
+

φ
s

)

+

ε
⁡
(

3
⁢
θ

)

,

 in which U A and U B are a pair of sinusoidal signals with an amplitude of U m and a phase difference of φ s , U 1 , U 2 , U 3 and U 4 are output signals of the first, second, third and fourth linear Hall elements, θ is an actual electrical angle of a rotor, and ε(3θ) is third harmonic.

2. The method for measuring the flux-switching electric motor rotor angle on basis of linear Hall according to claim 1 , wherein the first linear Hall element is mounted in any slot of the stator of the flux-switching electric motor, a mounting slot of the second linear Hall element is away from a mounting slot of the first linear Hall element by N 1 slots, a mounting slot of the third linear Hall element is away from the mounting slot of the first linear Hall element by N 2 slots, a mounting slot of the fourth linear Hall element is away from the mounting slot of the first linear Hall element by N 3 slots, wherein N 1 is an even number, and N 1 ≠ks/(2p), N 2 is an odd number, and N 2 =(2k−1)s/(2p), k being any integer, s being the number of slots of the stator, and p being the number of pairs of electric motor poles.

3. The method for measuring the flux-switching electric motor rotor angle on basis of linear Hall according to claim 1 , wherein an expression for the pair of quadrature signals in the two-phase stationary coordinate system obtained by linear combination of the pair of sinusoidal signals is

[

U
α

U
β

]

=

[

1

0

cos
⁢

φ
s

sin
⁢

φ
s

-

1

Assignees

• Univ Southeast

Inventors

• Hua Wei
• Wang Yuchen
• Liu Kai
• Zhang Chao

Classifications

• H02P21/18

  Estimation of position or speed · CPC title

• H02K11/215

  Magnetic effect devices, e.g. Hall-effect or magneto-resistive elements · CPC title

• H02P6/16

  Circuit arrangements for detecting position · CPC title

• Y02E60/16

  Mechanical energy storage, e.g. flywheels or pressurised fluids · CPC title

• H02P25/022

  Synchronous motors (H02P25/064 takes precedence) · CPC title