Fault-ride-through performance improvement of a PMSG based wind energy systems via coordinated control of STATCOM

This paper presents a coordinated control which combines pitch angle of a wind turbine, flux control of permanent magnet synchronous generator (PMSG) and reactive power control of grid to enhance the low voltage ride through (LVRT) capability of PMSG based variable speed wind energy conversion system (WECS). The design process of controller parameters and the stability of proposed control strategy have been analysed. In this strategy, pitch angle controller is modified to adjust the pitch for power smoothing as well as LVRT during variable wind speed and grid fault respectively. Flux weakening controller is used to reduce the flux linkages of PMSG by supplying negative field regulating current to reduce the DC link overvoltage during grid voltage dips. Additionally, static compensator (STATCOM) is used to provide reactive power support during grid fault. Extensive simulations of proposed method have been carried out under different cases. The performance of the proposed controller is validated by time series simulation. The results are compared with Braking chopper (BC) based conventional control for verification.