Minimization of Transmission Loss with Consideration of Transformer Taps Constraint

This paper describes the solution of minimization of transmission loss with consideration of transformer taps constraint. The transformer taps are using as control variables for transmission loss minimization and maintain voltage profile when the disturbance occurs in system. When transformer taps are only used for minimization of transmission loss that has to control transformer taps close to center. Proposed methodology is to control the stages of transformer taps close to the center of transformer taps. The equation of transformer taps stages is included in the objective function and in inequality constraints. An optimal power flow problem is solved by using interior point method. The problem constraints are the power flow equation, the bound of the power system and stages of transformer taps. The performance of the method is illustrated in IEEE 14 bus, IEEE 30 bus, and IEEE 57 bus test system. Test results show that the transmission loss can be made minimum and transformer taps can be controlling close to the central tap.