A Controller Parameter Identification Method of PMSG-Based Wind Turbine Generator Based on Measured Impedance

Abstract

In this paper, a controller parameter identification method of direct-driven permanent-magnet synchronous generator (PMSG) based wind turbine generator based on measured impedance is proposed. Firstly, the system structure of PMSG-based wind turbine generator is described. The analytical impedance models of generator-side converter’s dc-port and grid- side converter’s ac-port are established, respectively, and the corresponding measured impedances are obtained by frequency scanning. Then, the identifiability of the controller parameters is demonstrated by parameter sensitivity analysis in impedance magnitude. On this basis, the controller parameters are identified by applying the nonlinear least-square algorithm to the analytical and measured impedances. Finally, a case study is carried out to validate the proposed frequency-domain identification method, and the results show that the proposed method is able to accurately identify all the controller parameters with different control bandwidths.