An Operation Strategy of SVR and ESS to Enhance Hosting Capacity of PV Systems in Distribution System

According to the 3020 RE policy of korean government, renewable sources including PV and WP systems have been actively installed and operated in distribution systems. However, if large-scale PV systems are interconnected in distribution system, hosting capacity in PV systems may be reduced because they may violate the allowable voltage limits(220±13V) due to reverse power flow of PV systems. Under these circumstances, this paper proposes the operation algorithms of SVR(step voltage regulator) and ESS(energy storage system) to improve the hosting capacity of PV systems. Specifically, optimal LDC setting values are obtained by calculation algorithm of LDC setting values for SVR using the Least-squares method that minimizes the error for the entire time interval based on the distribution characteristics of upper and lower limits for the sending voltage of SVR considering the reverse power flow by PV systems. In addition, the minimum introduction capacity of ESS is obtained by evaluation algorithm of the required capacity of ESS to maintain the customer voltage within the allowable voltage limits for each time interval. From the simulation results, it is confirmed that the proposed algorithms are useful and practical tool to improve the hosting capacity of PV system. Copyright © The Korean Institute of Electrical Engineers.