Some Studies on Design of Current Controllers for a Grid Connected PWM Inverter to Improve Power Quality

Abstract

newlineThe single phase grid connected inverter converts DC power generated from a renewable energy source such as solar panels, into AC power that can be fed into the utility grid. The inverter synchronizes the AC voltage output of the solar panels with the grid voltage, ensuring that the power injected into the grid is in phase with the utility grid and meets the grid requirements. newlineThe current research work proposes method to achieve constant DC link voltage by predicting solar irradiance using Decision Tree classifier. Logistic regression, random forest and decision tree algorithms have been used to achieve desired goal among which Decision tree gave the maximum accuracy. Comparative analysis for various controllers like Single Band Hysteresis Current Controller (SBHC), Double Band Hysteresis Current Controller (DBHC) and Modified Hysteresis Current controller (MHCC) for grid connected single phase inverter have been made also. newlineSliding Mode control is a nonlinear control method that is robust to system uncertainties, disturbances, and parameter variations. It is combined with double band hysteresis current controller and modified hysteresis current controller to control grid voltage, grid current and reduce THD. A novel combination of SMC-MHCC has been proposed in this work. newlineFurther, fuzzy Sliding Mode Control (FSMC) has been discussed in present work. It is a type of control strategy that combines the principles of fuzzy logic and Sliding Mode Control (SMC). A novel combination of SMC with DBHC is also proposed in this work. The goal of FSMC is to achieve robust and adaptive control in systems that are subject to uncertainties, parameter variation and disturbances. The results of various current controllers (HCC, MHCC) have been validated in hardware using RT-LABS.