Averaged Model of Type-4 Wind Energy Conversion Systems Considering Fault Ride through Capability

Control design and stability analysis of wind energy conversion systems (WECSs) involve multiple repetitive operation scenarios or a large number of wind turbines. Although the detailed-switching-based electromagnetic transient models can accurately simulate the transient characteristics on different time scales, its application in the above scenarios is limited by the low computational efficiency. This paper proposes a dynamic average-value model (AVM) for the type-4 wind power generation system, which consists of a six-phase permanent magnet synchronous generator (PMSG) and a dual converter channel. To ensure the numerical stability and compatibility with adjacent components, the interface form between converters and adjacent components are firstly designed. Then, average-value equations are constructed for the two-channel converter and dc chopper circuit. Finally, the accuracy and computational efficiency of the proposed model are validated through comparisons with the detailed switching model in both time-domain simulations and frequency-domain analyses.