Patent · US Expired

Torque angle and peak current detector for synchronous motors

US4991429A · kind A · utility

80Cited by
4References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 28, 1989
Grant dateFeb 12, 1991
Priority date
Expiry dateDec 28, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R31/34
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A torque angle and peak current detector for a three-phase synchronous motor utilizes a phase-locked loop to generate a digital stator field position signal phase locked to the stator current. The phases of digital -sine and cosine reference signals generated from the field position signal are compared with x and y stator current component signals in multiplying digital to analog converters to generate a phase error signal which is driven to zero with the reference signals in quadrature with the current component signals at phase lock. The reference signals are also multiplied by in-phase current component signals and the products are summed to generate the peak current signal. A digital rotor angle position generated by a resolver and an analog to digital converter is subtracted from the digital field position signal to generate the torque angle signal.

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