Abstract: This paper describes the reactive power control on 3 phase, 6.9 kVA, 10A, and 440V transformer. We know very well that, the reactive power is important for support the active power but it should be at desire level if it is not then problems arises. In this project, a more reliable, technically sound, fast acting and low cost scheme is presented by organizing the thyristor switched capacitor elements in binary sequential steps. This enables the reactive power variation with the smallest amount possible resolution. In addition a thyristor controlled reactor of the lowermost step size is operated is combination with capacitor bank so as to reach continuously variable reactive power. In addition the enhancement transformer loading capability the shunt capacitor also progresses the feeder performance, reduces voltage drop in the feeder & transformer, enhanced voltage at load end, improves power factor, develops system security with superior utilization of transformer capacity, gives scope for additional loading, increases over all efficiency, saves energy due to concentrated system losses, avoids low power factor penalty, and reduces maximum demand charges.

Keywords: Reactive Power, Thyristor Binary Compensator, Static Var Compensator, Thyristor Switched Capacitor, Capacitor Bank, Thyristor Controlled Reactor, Binary Sequential Stages, Power Factor etc.