Performance of Stability of an Excitation System with Time Delays Using Pid Controller

The effect of time delay is very important for the consideration of stability of a generator excitation control system. Measurement devices, communication links used for data transfer are responsible for the significant time delays. This paper presents the effect of time delays on the stability of generator excitation control system. The maximum amount of time delay known as delay margin is determined theoretically by using PID controller that the excitation system can sustain without losing its stability. For certain values of time delays, the excitation control system loses the stability. A stabilizer is used to generate supplementary control signals for the excitation system in order to dampen the low frequency oscillations for the time delays. A simulink model using PID controller with stabilizer used for the better stable operation of the generator excitation control system is presented.