Comparison of Ideal Transformer Method and Damping Impedance Method for PV PHIL Experiments
Adam Summers, Javier Hernandez-Alvidrez, Rachid Darbali-Zamora, Matthew Reno, Jay Johnson
Sandia National Laboratories, Albuquerque, NM, United States

The Ideal Transformer Method (ITM) and the Damping Impedance Method (DIM) are the most widely used methods when connecting power equipment to a power-hardware-in-the-loop simulation. Both methods have been studied for their stability and accuracy for static loads in real-time simulations, but not during dynamic grid-support operations like those from volt-var, frequency-watt, and fixed power factor functions. In this work, we experimentally validate the two methods of connecting a physical PV inverter to a real-time operating system and evaluate them for dynamic stability and accuracy when operating with grid-support functions.