Patent · US Expired

Dynamic parallel inductive stabilizer for synchronous machines having torsional oscillations

US4302715A · kind A · utility

18Cited by
5References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 15, 1979
Grant dateNov 24, 1981
Priority date
Expiry dateJun 15, 1999

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02P9/10
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

This concerns a compensator for electrical lines fed by a turbine-generator. The mechanical properties of the turbine-generator are such that modulation of the terminal voltage is possible due to subsynchronous mechanical torsional oscillations. If the carrier frequency or synchronous frequency of the generator minus the torsional oscillation frequency is equal to the resonant frequency of the electrical line driven thereby, a relatively large side band current may flow in the electrical line at the resonant frequency. The effect of this current may feedback through the air gap of the generator to increase the torsional oscillation. A boot strapping effect between the electrical properties of the line and the torsional oscillation may thus result which could ultimately end in shaft breakage. The present apparatus utilizes the torsional oscillation signal to modulate compensating inductance connected in parallel between the lines of the electrical system to thus generate a small current at the appropriate electrical resonance frequency. This current leads to the production of a compensating line current at that frequency which in turn opposes the previously described undesirable eff…

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