Patent · US Expired

Drive and protection system for variable speed motor

US4780656A · kind A · utility

15Cited by
4References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 8, 1987
Grant dateOct 25, 1988
Priority date
Expiry dateSep 8, 2007

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02H1/06
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An electronic control for a motor drives the motor with pulses of current, and protects the motor from extreme values of line voltage and motor current. A current sensor, connected in series with a conductor which supplies current to the motor windings, develops a monitoring signal that is sensed for the purpose of shutting down the motor when the monitoring signal indicates that the motor current is excessive. A power supply in the control isolates the control from the AC line voltage, provides regulated DC voltages to power various portions of the control, and provides an unregulated DC sense voltage which indicates when the AC line voltage is too high or too low so that the motor can be shut down.

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