A methodology for characterizing and modeling inverters for grid integration studies using Power Hardware-in-the-Loop

A methodology is proposed and executed to characterize and model inverters for grid integration studies using Power Hardware-in-the-Loop. A Hardware-in-the-Loop system is configured using a Real-Time Data System (RTDS), grid simulator, load bank, photovoltaic inverter, DC power supply and bus system. A characterization scheme is developed on the RTDS that is based on the abnormal grid conditions and tests outlined in IEEE 1547 Standard for Interconnecting Distributed Resources with Electric Power Systems. It was found that it is possible to characterize the inverter's grid protection controller's response to abnormal voltage, abnormal frequency and islanding conditions without prior knowledge of intimate control algorithms or hardware configuration. A model of the system was then created in Matlab Simulink using the data obtained from the characterization process. The inverter model is developed such that the detection and response to the stated abnormal grid conditions of the model emulates that of the actual inverter.