Smart Inverter Voltage Control on Distribution Feeders

Smart inverters are studied in both the dynamic/transient and steady state in a simulation environment. Using EPRI OpenDSS, five real California feeders are simulated over a 95 day period while the PV penetration and smart inverter fraction are varied. From the simulations, it is shown that smart inverters operating under different Volt/VAr based control schemes improve feeder conditions. The improvement is shown with regards to voltage maxima and minima, tap operations, and variability. Feeder total line losses increase due to the presence of smart inverters, as a result of increased current in the lines associated with reduced bus voltages. Increasing the smart inverter fraction and removing the deadband from the Volt/VAr control curve produces the largest improvements in these quantities. On one feeder, using smart inverters alone reduced the number of tap operations to zero, showing potential for the inverters to be used as primary voltage regulators (assuming proper PV penetration and placement). Finally, based on the results, sizing of the inverter was shown to be important in ensuring smart inverter effectiveness, and is recommended for future work.