Patent · US Expired

Variable-speed generator/motor system

US4812730A · kind A · utility

14Cited by
7References
8Claims
0Family size

Assignees

Inventors

Key dates

Filing dateApr 6, 1987
Grant dateMar 14, 1989
Priority date
Expiry dateApr 6, 2007

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02P2101/10
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A generator/motor system comprises a generator/motor having a primary winding and a secondary winding installed on the motor rotor coupled to a prime mover/load, a main circuit interposed between a power system and the primary winding of the generator/motor, an excitation circuit including a frequency converter inserted between a part of the main circuit and the secondary winding of the generator/motor, a frequency difference detector for determining the difference between the frequency of the power system and a frequency dependent on the rotational speed of the load, and a phase-shift control device for controlling the firing phase of the frequency converter in the excitation circuit by use of a signal from the frequency difference detector as a reference signal. In normal operation, a frequency signal following the frequency of the power system is produced, while at the time of a disturbance of the power system, the same frequency signal of the power system as before the disturbance continues to be produced thereby to keep the system in stable operation. For this purpose, a starting electric machine, a synchronous motor and a synchronous generator are aligned, and an output of th…

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