A Type-4 Wind Power Plant Equivalent Model for the Analysis of Electromagnetic Transients in Power Systems

This paper introduces an accurate and computationally efficient reduced-order dynamic equivalent of a Type-4-based wind power plant (WPP) for the analysis of electromagnetic transients (EMTs) in the power system external to the WPP. The proposed model significantly reduces the computational resources and the simulation run time while preserving the WPP response fidelity in the desired frequency range, e. g., 0 to 50 kHz. The proposed WPP equivalent model is composed of two parts: 1) a frequency-dependent equivalent model which represents the WPP passive component in the entire frequency range and 2) a dynamic equivalent model that represents the WPP supervisory control and the aggregated low-frequency dynamics of wind-turbine generator (WTG) units. The latter can be constructed from the: 1) dynamic generic models; 2) vendor-specific models; or 3) user-defined models. The proposed model is incorporated as a software module in the PSCAD/EMTDC environment, and its efficiency and accuracy are verified based on comparing the results with those of a detailed model.