Power Hardware In the Loop and Ancillary Service for Voltage Regulation in Low Voltage Grid

Power production via traditional generators play a major role to meet demand, however, the trend is shifting towards utilization of distributed renewable sources. Distributed Energy Resources (DER) becomes a means to support loads locally. As DERs are typically intermittent sources, there are challenges associated with the high level of penetration of these resources that are of concern to grid operators. There are also opportunities associated with this technology as the inverters connecting the DERs could support voltage regulation by performing reactive power compensation in the grid.The concept of utilizing droop controlled DERs as reactive power resources is explored in this paper. As the active power production fluctuates with solar insolation, the spare capacity of the inverters could be employed to provide effective reactive power compensation to support the grid.In this paper, Power Hardware in the Loop (PHIL) simulation was employed where a single-phase PV inverter hardware is operated in parallel with three other real-time simulated inverters to deliver ancillary services. The results have shown that the switching steps of the On-Load Tap changer transformer (OLTC) were reduced, thus improving overall system performance.