Controllable Var Compensator: A Potential Solution to Loadability Problem of Low Capacity Power Systems

The stability of the voltage at the receiving end of radial transmission links puts a limit on the amount and character of load that can be connected at that end. The paper demonstrates the potential of having a static var compensator SVC for supporting the voltage at the load end and therefore increasing the loadability of such links. Radial links of different transmission voltages and lengths as well as loads of different characters have been considered in showing the effectiveness of SVC. A general formula defining the sensitivity of receiving end voltage to shunt compensation has been developed. With the aid of this formula the regulator gain of the used SVC control model has been dimensioned and the steady state loadability limits of radial transmission links, at different load character, can be established analytically.