Improvement of generator output and stability margin by use of a dedicated static VAR compensator

Abstract

The concept and impact of using a dedicated, current-based static VAR compensator (SVC) located at a generator bus to produce any required reactive power is examined. When relieved of the burden of reactive power production, the generator can then operate with an increased average power production capability. Counter argument to this proposed simple concept of unity power factor (PF) operation of a generator is the concern over potentially reduced stability margin that the generator faces when exposed to a disturbance. The major contribution of this paper is the introduction of a novel control scheme for the SVC that configures the device to function as an energy source and sink during a transient stability contingency. The control objective is to maintain the generator energy conversion constant so that rotor mechanical oscillation is practically eliminated. Simulation results validate the proposed control method.