Analysis of Reduced Switch Count Multilevel Inverter for Renewable Energy System

Abstract

The need of new sustainable and renewable energy sources has been increasing from past newlinedecades due to depleting fossil fuel and global warming. Wind energy and solar energy are newlinepopular and in demand due to advancement in power electronic techniques and technoeconomic newlinebenefits. The use of solar electric energy is extensive due to advancement in newlinemanufacturing technologies and economics advantages. In solar electricity system, DC AC newlinepower converter plays important function and being used for high power as well as high newlinevoltage applications. DC-AC energy converter has broad range of energy uses such as in newlinepower quality device, adjustable frequency drive, UPS, HVDC system, SVC, fuel cell, newlineFACTS, marine propulsion and solar cell etc. It is categorized as current source inverter newline(CSI) as well as voltage source inverter (VSI) that produce AC voltage and current by making newlineuse of DC voltage source. Based on the output waveform, it is classified as: square wave, newlinealtered sine wave innovation (quasi sine wave), square wave PWM as well as multilevel newlineinverter (MLI). MLIs generates close to sinusoidal voltage waveform from the usage of newlinecapacitor, power packs, inexhaustible sources of energy as well as input DC level. Higher newlinedegree of MLIs creates quality voltage result with diminished switching stress. newlineMLIs receive attention from both academy and industry due to inherent features such as newlineability to operate in higher voltage or power condition, improved quality of output waveform. newlineReview of literature reveals topologies of MLI been realize and has been divided into three newlinecategories, namely, diode clamped (DC) MLI or neutral point clamped (NPC), flying newlinecapacitor (FC) MLI and Cascade H-Bridge (CHB) MLI. Cascaded H-bridge and neutral point newlineclamped are popular hardware implemented topologies, especially in growing technological newlinefield of renewable energy. CHB-MLI has simplicity of control, low rating and less number newlineof power semiconductor switches. It does not require clamping diode and voltage balancing newlinecapacitor.