An artificial intelligence based controller for multilevel harmonic filter

摘要

This paper demonstrates an Artificial Intelligence (Al) based controller for 5-level, cascade H-bridge inverter for harmonic compensation and dc voltage regulation under different loading conditions for high voltage applications. In the proposed topology, the artificial neural network (ANN) is applied for obtaining compensating current and two Fuzzy Logic Controllers (FLC) are designed for dc voltage regulation and current error adjustment. The fuzzy logic controlled current error is then used for multicarrier Phase Shifted Pulse Width Modulation (PSPWM) for generating gate pulses for the inverter. The 5-level, Cascade H-bridge Multilevel Inverter (CHBMLI) is used as active harmonic filter. The ANN based instantaneous power theory is applied for reference current estimation. Simulation results are obtained in MATLAB/ SIMULINK for diode bridge rectifier with RL/RC as nonlinear loads, using simpower system and fuzzy tool box. The proposed topology performance is justified through exhaustive simulation under various loading conditions. The total harmonic distortion in source current (THD_i) is being used as evaluation criteria to quantify the results. The THD_i obtained by applying PI and Al based controller are compared and are well within the IEEE 519, 1992 std. limits. The proposed method is verified through experimentation by developing prototype with dSPACE 1103 interface.