Patent · US Expired

System and method for detection and control of circulating currents in a motor

US5825597A · kind A · utility

87Cited by
54References
27Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 25, 1996
Grant dateOct 20, 1998
Priority date
Expiry dateSep 25, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02H7/0838
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A system for controlling circulating currents in a motor. A power supply link having upper and lower rails supplied by a power supply provides power to the motor windings. The power supply link also has power switches responsive to a motor control signal for selectively connecting the rails to the windings in alternating on and off intervals. The system includes a first resistive shunt in the upper rail of the power supply link between the power supply and the power switches and a second resistive shunt in the lower rail of the power supply link between the power supply and the power switches. The power supply link routes current circulating in the power supply link and windings through either the first or second resistive shunt for continuously sensing current in the rails. The system also includes a current regulation circuit which generates an overcurrent signal as a function of the current sensed in either the first or second resistive shunt exceeding a maximum current level. A control circuit responsive to the overcurrent signal causes each of the power switches to become nonconducting thereby to prevent excessive current from circulating in the motor.

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