Modeling of Power Converters for Model Predictive Control

Abstract

This chapter deals with the modeling of power converters employed in Type 3 and 4 variable???speed wind energy conversion systems (WECS), particularly for 2L??? voltage source converters (VSCs) and NPC converters. Model Predictive Control (MPC) uses a completely different approach and does not require comprehensive knowledge on the space vector diagram, SV diagram sectors, reference voltage vector, and adjacent vectors. All the voltage vectors are utilized to predict the future behavior of the variable to be controlled, and an optimal voltage vector that fulfills the control objective is selected from them. The proper selection of switching signal leads to the accurate control of reference variables, such as generator or grid currents and balancing of DC???link capacitors voltage. The generalized approach for the modeling reveals that the models can be extended to multilevel and multiphase applications in an intuitive manner. The operational modes and space vector diagrams of various power converters are presented to aid the discussion and to show proof of concept.