Mitigation of voltage variation by REMS for distribution feeders

This study develops a renewable energy management system (REMS) for the control of photovoltaic (PV) smart inverters to mitigate the voltage violation of distribution systems with high penetration of PV installation. The impact analysis of distribution feeders due to real power generation of PV system and reactive power compensation by smart inverters has been embedded in REMS to solve the voltage level at the PV connection point to enable the decision making of Watt-Power factor control method for the inverters. To verify the effectiveness of smart inverters for the control of system voltage, a PV system installed in a distribution feeder of Taiwan Power Company (Taipower) has been selected for field testing. The real power, reactive power and voltage of PV system have been collected. The impact analysis of PV integration is performed to solve the mitigation of voltage variation by smart inverters using the actual change of PV power generation after the proposed control of smart inverters. It is found that the voltage variation at the test PV system is very consistent to the field test results. Computer simulation of a distribution feeder with a large PV farm has been executed to illustrate that the control of smart inverters can reduce the curtailment of renewable power generation dramatically for a distribution system with high penetration of PV systems.