Innovative Volt/VAr Control Philosophy for Future Distribution Systems Embedded With Voltage-Regulating Devices and Distributed Renewable Energy Resources

Abstract

Conventional voltage-regulating devices such as load tap changers, voltage regulators, and local capacitor banks are commonly used for voltage-regulation purposes in medium-voltage distribution systems. Although such devices exhibit excellent capability for Volt/VAr control (VVC) support, fine-tuning of their controller parameters and enactment of Volt/VAr support by renewable distributed generation (DG) units is essential for effective and efficient operation of future distribution systems embedded with wind and solar-Photo-voltaic (PV) units. In this paper, an innovative algorithm is conceptualized for control set-point re-adjustment of different VVC devices for coordinated voltage control in distribution systems. The intended VVC strategy is able to minimize the voltage variations including voltage drop and rise cases mainly caused by power output of renewable DG units that cannot be solved by voltage regulating devices due to their time-delayed operation. Moreover, the control algorithm is proposed to be implemented online using advanced distribution management system for effective voltage control. The simulation studies are carried out using the test distribution system derived from an electricity network in New South Wales, Australia. The simulation results show that voltage regulation can effectively be achieved in renewable rich future distribution systems by applying the proposed tuning algorithm, which has been designed based on a new VVC philosophy.