Arrangement and method for monitoring a PSM-machine

Patent metadata

Field	Value
Publication number	US-10270378-B2
Application number	US-201615381268-A
Country	US
Kind code	B2
Filing date	Dec 16, 2016
Priority date	Dec 21, 2015
Publication date	Apr 23, 2019
Grant date	Apr 23, 2019

Abstract

A method for monitoring a PSM machine having three phases including detecting whether one or more current sensors disposed on a phase of the machine has malfunctioned. If a malfunction is detected, a voltage indicator is calculated from a voltage amplitude and a voltage phase of an input voltage of the machine in a d, q-coordinate system by two different calculations. The first calculation includes calculating the input voltage based on a phase current, target currents, and an electrical angle of the machine. The second calculation includes calculating the input voltage based on target values of a reference voltage amplitude and a reference voltage phase. The method also includes determining the voltage amplitude and the voltage phase of the input voltage of the machine and comparing the values of the respective voltage amplitudes and voltage phases from the input voltage in the first and second calculations.

First claim

What is claimed is:

1. A method for monitoring a PSM machine having at least or exactly three phases (U, V, W), which are operated by a field oriented control, the method comprising:
determining whether one or more current sensors disposed on a phase of the PSM machine has malfunctioned;
wherein if a malfunction of the current sensors is detected, such that only one of the current sensors remains functional, the method also comprises calculating a voltage indicator from a voltage amplitude and a voltage phase of an input voltage of the PSM machine in a d, q-coordinate system using the following two different calculations:
wherein the first calculation comprises calculating the input voltage based on a phase current measured by a functioning current sensor, target currents, and an electrical angle of the PSM machine; and
wherein the second calculation comprises calculating the input voltage based on target values of a reference voltage amplitude and a reference phase;
determining the voltage amplitude and the voltage phase of the input voltage of the PSM machine; and
comparing the values of the voltage amplitude and the voltage phase determined from the input voltage in the first calculation and the values of the voltage amplitude and the voltage phase determined from the input voltage in the second calculation.

2. The method of claim 1 , wherein in the first calculation, the calculating of the voltage indicator from the voltage amplitude and the voltage phase of the input voltage is based on a phase of a current indicator Θ I and a current indicator amplitude {right arrow over (I)} s ;
wherein the first calculation also comprises calculating the phase of the current indicator Θ I via a load angle Θ Last Ref and an electrical angle Θ el of the PSM machine according to the following equation:
Θ I =Θ el +Θ Last Ref ;

wherein the first calculation also comprises calculating the load angle of the PSM machine Θ Last Ref from filtered currents I sdRefF and I sqRefF , that are offset target values of the d, q-currents, according to the following equation:

⊖

Last
⁢

⁢
Ref

⁢

=

arctan
⁢

IsqRefF
IsdRefF

;

wherein the first calculation further comprises calculating the current indicator amplitude {right arrow over (I)} s as a function of the current indicator in a U, V, W-coordinate system I su , I sv , I sw ;
wherein the calculating of the current indicator amplitude {right arrow over (I)} s in phase U comprises the following equation:



I
→

s



=

Isu

cos
⁡

(

Θ
⁢

⁢
I

)

;

wherein the calculating of the current indicator amplitude {right arrow over (I)} s in phase V comprises the following equation:



I
→

s



=

Isv

cos
⁡

(

Θ
⁢

I

+

4
⁢

⁢
π

3

)

;

and
wherein the calculating of the current indicator amplitude {right arrow over (I)} s in phase W comprises the following equation:



I
→

s



=

Isw

cos
⁡

(

Θ
⁢

Assignees

• Zahnradfabrik Friedrichshafen

Inventors

• Lamsahel Hassan

Classifications

• H02P6/16

  Circuit arrangements for detecting position · CPC title

• H02P27/08

  with pulse width modulation · CPC title

• G01R31/343

  in operation · CPC title

• H02P21/18

  Estimation of position or speed · CPC title

• H02P21/22 Primary

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