DFIG wind turbines with very sparse and sparse Matrix Converters to control frequency

Abstract

Matrix converters (MC) can convert variable AC input to desired AC output. While a change occure in power systems i.e. a fault, loss of generation or changes in wind speed, in this study, Matrix Converters can properly improve the behavior of oscillatory system to be more stable. In this study, frequency of system is taken into consideration, frequency measurement is done by proper use of phase locked loop in different case studies. Two new structures base on sparse matrix converter (SMC) and also very sparse matrix converters (VSMC) introduces to be implement instead of B2B converters in DFIG wind turbine structures. The structure don't have any DC link. The model also compared with conventional matrix converter (CMC) uses with wound rotor induction generator. Symmetric sequence method utilized in the study for inversion and rectification stages of direct space vector strategy (SVM) for SMC and VSMC. For CMC indirect space vector modulation strategy (ISVM) used that expressed in detail. Two different models for wind turbine block proposed in the simulations to model shaft torque-speed behavior. Results show the consistency of the proposed structure to control frequency of the proposed power system when integrated to DFIG wind turbines base on VSMC and SMC matrix converters.