Patent · US Expired

Method and apparatus for determining the rotor resistance of a rotating-field machine

US4884023A · kind A · utility

16Cited by
3References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 9, 1989
Grant dateNov 28, 1989
Priority date
Expiry dateJan 9, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02P2207/01
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

In order to determine the rotor resistance of a rotating field machine, a current is impressed in the stator via a field-oriented control, which current has a harmonic component above the nominal frequency of the machine. From the current, the rotor position and a readjustable parameter value for the rotor resistance, a current model calculates a field-parallel EMF component EF1, the harmonic component EF1.sub..about. of which is isolated. In addition, a voltage model calculates from the current and the voltage, the EMF vector as the current component reference value EF1' and its harmonic component EF1'.sub..about.. A correction control CR1 readjusts the parameter r.sub.R of the rotor resistance until the difference of the two isolated harmonic EMF components disappears. The test signal has practically no influence on the flux and the torque of the machine. At the same time, the stator resistance r.sub.S and the stray inductance x.sub.St can be determined.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.