Frequency Regulation using Smart Inverters in High Penetration Distributed PV Scenario

The classical frequency regulation problem of a medium voltage distribution network with high Photovoltaic (PV) penetration is addressed. The methodology, using multiple distributed smart inverters, is discussed thoroughly. The frequency control strategy shown here, is primarily based on the advanced Frequency-Watt Control (FWC) feature of the Voltage Source Inverter (VSI). This feature mimics the governor droop control of conventional synchronous generator and doesn't require costly communication infrastructure. Dead band coordination is discussed and a low-cost coordination strategy for multiple smart PV inverters is also proposed based on the Inverse Definite Minimum Time (IDMT) principle. Dynamic frequency regulation on a modified IEEE-13 bus test system is simulated and analyzed to verify the effectiveness of the proposed solution. The simulation results show evidence that the proposed coordination strategy is effective in providing a tight frequency regulation.