Performance Analysis of Converters and Multilevel Inverters for Renewable Energy Systems

Abstract

The main objective of this research is implementation of 7-level symmetric Multilevel Inverter (MLI) using minimum switches with PI-controller and positive and negative output multiple Lift-Push-Pull switched capacitor converter for Renewable Energy Source (RES) based applications. MLIs available in the literature have more features in turn more switches. The system with more switches would not opt for wide range applications. To rectify the problems in existing systems a 7-level MLI with reduced number of switches using carrier based PWM techniques proposed in this research. The performance parameter, Total Harmonic Distortion (THD) is analyzed with reduced Switching loss, size and cost. The system is developed using MATLAB-SIMULINK and shows the effectiveness of the proposed strategies. newlineThe micro-power-consumption technique requires high power density DC/ DC converters and power supply sources. In this research, a PI and Fuzzy Logic Controllers for an elementary circuit of positive output (P/O) push-pull switched capacitor converter has developed for high power density applications with high sustainability under enormous line and load disturbances. The voltage lift technique is a popular application in electronic circuit design. The power converter performs DC-DC step-up voltage conversion with high efficiency, high power density and cheap topology in a simple structure. The proposed converter combines both switched-capacitor and voltage lift techniques. Referable to the time varying and switching nature of the power electronic converter their dynamic behavior becomes highly non linear. Conventional controllers are incapable of providing excellent dynamic performance and hence the fuzzy logic controller can be used as a feed forward controller for controlling power electronic converters. The control algorithm is developed to ensure tracking of the reference voltage and rejection of system disturbances by successive measurements of the converter output voltage at certain time instants within a conduction period. The simulation of PI and Fuzzy logic newlinevi newlinecontrols have been carried out using MATLAB/Simulink software to evaluate the controller s performances. Key words: Multilevel Inverter, Multilevel Converter, Luo converter, DCDC converter, PI Controller, Fuzzy Controller Renewable Energy Source, Total Harmonic Distortion, High Power Gain, High Efficiency, Low EMI. newline