Patent · US Expired

Alternating current motor control method and system

US4044284A · kind A · utility

7Cited by
7References
30Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 19, 1975
Grant dateAug 23, 1977
Priority date
Expiry dateAug 19, 1995

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02P21/10
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A new and improved motor control method and system wherein the frequency of the rotating electro-magnetic flux produced in an alternating current machine, is sensed and compared to a desired value of machine flux frequency to derive an output error control signal. The output error control signal is then applied to control the frequency of the alternating current supplied to the machine in a direction and by an amount necessary to zero any difference in the sensed frequency and the desired frequency of machine flux. In preferred embodiments the actual value of the electromagnetic flux produced across the rotor-stator gap of the motor, is sensed and used as the controlling criterion in the motor control system. The magnitude of the alternating current supplied to the motor is separately controlled in accordance with some other predetermined motor operating characteristics such as motor torque, load current, etc.

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