Reactive Power Dispatch scheme evaluation for synchronous based distributed generators to reduce real power loss in distribution systems

The enhance benefit use of reactive power additional supplied by synchronous based distributed generators to reduce real power loss in distribution system is studied in this paper. Objective is to compare the amount of loss reduced between the constant power factor (CPF) and the optimal reactive power dispatch (ORPD) schemes. The former is a traditional scheme of controlling reactive power with a specified constant power factor whereas framework of the proposed ORPD is formulated for optimizing real power loss whose obtained result is the amount of reactive power injected hourly. A linear programming is adopted in accordance with sensitivity factors to solve for the optimal solution of the ORPD scheme. Several scenarios of a 38-bus radial distribution system together with ten load profiles recorded from the Provincial Electricity Authority (PEA)psilas substation in Thailand are examined. Analysis of these two schemes are performed to verify the worth and feasibility for implementing the proposed scheme in a real system.