STABILITY PROBLEMS . IN A TWO MACHINE SYSTEM WITH VOLTAGE REGULATOR AND GOVERNOR ACTION.

Abstract

Control systems are essential for raising the dynamic stability limit of the electrical machines but unless they are properly .designed , they tend to make the system unstable. which would otherwise have been stable. Thus there has been a clear ne ~d to ascertain the type of feed back and range of amplification of the error signal necessary to be fed in a closed loop system that shall add to the system stability. In this paper., the rk done by Mukhopadhyaya( 16) on the stability of synchronous machine connected to an infinite Bus and that of Choudhry and Mukhopadhyaya (20) on a two machine system has been further extended to find out the ranges of gain, of the voltage regulator and the governor control systems that makes the system stable. The method of small oscillation characterised by small displacement theory has been applied to linearise the non-linear equation of the system and the probable region of the gain of the controlling elements has been deter-mined by the method of Domain Separation. PJrther,as desired by Good$n (26),, the effect of the system interaction frequency on the machine angle and consequently on the stability of the system has been studied.