Voltage Dip Rating Reduction Based Optimal Location of DVR for Reliability Improvement of Electrical Distribution System

ABSTRACT:This paper presents a new method to reliability improvement of distribution system by optimal sizing and placement of Dynamic Voltage Restorer (DVR) based on reducing the number of sagged bus and outage load. The PSO based approach is used to solve the DVR optimization problem with considering capital cost of DVR installation and interruption costs due to interruption of loads in sensitive point. In this paper using ETAP software, with considering the three phase fault, the worst point that leads to the propagation of voltage sags to most number of system buses, is investigated and located. Simulation results show that the proposed method is efficient and feasible for improving the system reliability level by reducing the number of sagged bus and load outages and momentary interruptions. Finally in this paper, after optimal location of DVR, the reliability improvement is investigated through expected energy not supplied (EENS) index, average system interruption frequency index (ASIFI) and the momentary average interruption frequency index (MAIFI).