Patent · US Expired

Method for determining a stator flux estimate for an asynchronous machine

US5589754A · kind A · utility

9Cited by
4References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 24, 1995
Grant dateDec 31, 1996
Priority date
Expiry dateAug 24, 2015

Classification

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

Abstract

Apparatus for determining an estimate for the stator flux of an asynchronous machine when the supply frequency .omega..sub.s, stator inductance L.sub.s, at least one of stator resistance R.sub.s and an estimate R.sub.se therefor, and short-circuit inductance .sigma.L.sub.s are known, is carried out by structure for measuring the stator current 1.sub.s and stator voltage u.sub.s, calculating a difference voltage by subtracting at least one of the product of the stator resistance and the estimate thereof and the stator current from the stator voltage, integrating the difference voltage in relation to time to give a stator flux estimate .psi..sub.se, subtracting, prior to integrating a correction term based on the feedback stator flux estimate .psi..sub.se and being proportional to the product of the difference variable and the direction vector C given therefor, from the difference voltage, determining the difference variable from the equation: EQU (.psi..sub.se -L.sub.s 1.sub.s).multidot.(.psi..sub.se -.sigma.L.sub.s 1.sub.s)=.epsilon. and forming the direction vector C from the feedback stator flux estimate .psi..sub.se by turning it for the angle .theta. which is dependent on the o…

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