Multi-Objective Fuzzy Based Procedure for Optimal Reactive Power Dispatch Problem

–This paper proposes a fuzzy based procedure to solve the optimal reactive power dispatch (ORPD) problem. Comparison studies between two linear fuzzy models namely triangular and trapezoidal fuzzy models, to solve ORPD problem is carried out for control and dependent system constraints. The proposed fuzzy ORPD model handles fuzzy objectives and constraints to obtain the optimal operational settings of control variables during different operating conditions. The control variables are the generator voltages, transformer tap ratios, and switchable reactive power sources while the dependent variables are the load voltages, generator reactive power, and power flows through the transmission lines. The proposed fuzzy-based ORPD procedure is applied to the West-Delta region system as a part of Egyptian Unified Network (EUN). Simulation results show that the fuzzy modeling of objectives and constraints can improve the ORPD solutions by obtaining the optimal settings of control variables with efficient fine tuning of power system variables. Also, these studies show that the changes in membership models have a great effect on the control variables setting, elimination the overflows in the critical lines and minimizing the total transmission power losses as well as efficient treatment of the multiobjective problems.