Patent · US Expired

Gain normalization technique for controlled current induction motor system

US4243927A · kind A · utility

28Cited by
5References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 2, 1978
Grant dateJan 6, 1981
Priority date
Expiry dateOct 2, 1998

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02P23/07
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An a-c induction motor powered from an adjustable frequency and adjustable magnitude power source is provided with a feedback control system whose gain is varied as a function of the magnitude of flux developed in the motor in order to normalize system response throughout the motor operating range. The control system is a two-loop system in which one loop adjusts excitation frequency and the other loop adjusts excitation magnitude with the excitation frequency loop being responsive to a torque command signal and a torque feedback signal to generate an error signal which is utilized to adjust the excitation frequency of the power source. System gain is varied by modifying the error signal as a function of the magnitude of flux developed in the motor. Preferably this modification is performed by dividing the error signal by a signal representative of the magnitude of motor flux.

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