A New Online Optimal Controller for Tracking of Currents of two-level Voltage Source Converters

This paper proposes a new optimal feedback controller for two-level voltage source converters VSC's, for current regulated voltage source converters, which allows compensate the harmonics of current produced by nonlinear loads and load reactive power. The aim of the present paper is to describe a novel switching signal generation technique called optimal controller which guarantees that the injected currents follow the reference currents determined by the compensation strategy, with the smallest possible tracking error and fixed switching frequency. Reference currents is calculated by instantaneous positive sequence load currents and utility voltages with PQ theory. It is compared with well-known hysteresis current controller HCC. The mathematical model of VSC will be addressed in detail. The validity of presented method and its comparison with HCC is studied through simulation results by MATLAB software.