Patent · US Expired

Induction motor digital control system

US4672287A · kind A · utility

15Cited by
4References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 25, 1986
Grant dateJun 9, 1987
Priority date
Expiry dateApr 25, 2006

Classification

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

Abstract

An induction motor control system in which the actual velocity of an induction motor follows a commanded velocity by correcting a difference between actual velocity and commanded velocity, and possesses a current negative feedback loop. The system comprises means (9) obtaining excitation current from actual velocity and a torque command of the difference, means (10) obtaining secondary current, which is load current, from the torque command, means (12) obtaining primary current amplitude and current phase based on the excitation current and secondary current, means (11) obtaining slip frequency from actual velocity and torque command, means (13) obtaining an excitation phase from the slip frequency and actual velocity, means (15) obtaining a current command in each phase based on primary current amplitude and current phase, means (16-21) obtaining a voltage command based on current deviation between the current command in each phase and feedback current from the current negative feedback loop, means (29) for correcting the back electromotive force based on excitation current, and means (22-24) superposing the electromotive force, which is for back electromotive force correction bas…

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