Review of Experimental Methods for Determining Harmonic Model Parameters of IBR Units

The global rise of renewable energies has led to the widespread incorporation of inverter-based resources (IBRs), encompassing wind turbines, photovoltaic arrays, batteries, etc. To clarify the impact of IBR on power quality, it is critical to construct the harmonic model and identify its parameters. According to the IBR’s harmonic model, the paper reviews three widely used experimental methods to determine harmonic model parameters, including the frequency scan method, the state-switching method, and the measurement-based harmonic coupling modeling method. Different measurement approaches determine their suitability for analyzing harmonic impedance, harmonic sources, and harmonic coupling relationships. Experimental verifications are conducted on the IBR laboratory platform, wind turbine converter, and photovoltaic converter. Results indicate that utilizing the Norton equivalent model for the IBR unit can significantly simplify the process of determining harmonic model parameters while retaining relatively high accuracy. Recommendations are finally provided to determine available harmonic parameters from engineering perspectives.