An integrated control system for sparse matrix converter interfacing PMSG with the grid

Abstract

This paper presents an integrated control system for Sparse Matrix Converter (SMC) to interface Permanent Magnet Synchronous Generator (PMSG) based wind turbine unit with the power grid. A carrier based PWM technique is extended and adapted for the SMC. Details of the proposed switching strategy and derivations of the modulation functions for both the rectifier and inverter stages of the SMC are presented. The inverter stage is controlled to regulate the speed of the PMSG for maximum power extraction. In addition, the rectifier stage of the SMC is controlled to deliver the generated active power from the PMSG to the grid at the required power factor to satisfy the reactive power demand. Moreover, the proposed interface system is adaptively synchronized with the grid. The Multi-Output Recursive Least Square (MO-RLS) algorithm is proposed to estimate the phase angle of the grid voltage. Furthermore, active damping scheme is integrated with the proposed control system to attenuate the oscillations caused by the LC filter of the rectifier stage. Numerical simulations are conducted to investigate the effectiveness and the fast dynamic performance of the proposed control system based on MO-RLS even during the speed disturbance. The proposed interface system succeeds to control active power with the desired power factor demand and to damp the oscillations of the SMC current and voltage.