Centralised Control of PWM Inverter in Hybrid Distributed Generation

Abstract

Renewable energy sources are play a vital role to provide electrical energy newlinein rural and urban areas. Optimized power electronics converters, Inverters and newlinecontrol algorithms are used to improve efficiency and reliability of the system. newlineNew single switching device ultra-gain isolated DC-DC converter is proposed here newlinefor extracting maximum power from multiple PV array configurations with an newlineisolated output port. It is capable to extract maximum electrical energy from serial, newlineparallel connected PV modules. Equivalent circuit model is derived for serial and newlineparallel connected solar PV cell with different internal performance parameters. newlineDifferent PV configuration with identical and non-identical modules is analysed. newlineAdditionally proposed converter is developed for energy management between newlinedifferent types of source, Grid and energy storage systems. The number of ports is newlinevaried based on number of sources, storage systems and Grid. The developed newlineisolated converter is accepting limitless, different types of sources and storage newlinesystems. Its operating mode is classified into different operating states. One ferrite newlinecore transformer with serial coupling capacitor is used to perform step up operation newlinewith reduced power switch. The converter is designed for energy management newlinebetween Photovoltaic (PV) array, Fuel Cell (FC), Super capacitor (SCAP) and newlineload. PV array and Fuel Cell are connected in unidirectional port, super capacitor is newlineviii newlineconnected in bi directional ports. Super capacitors are designed for transient load newlineand Photovoltaic array, Fuel Cell designed for steady state load. Grid is connected newlineto the converter throng 1: N ferrite core transformer and Three Phase Voltage newlineSource Inverter. Energy transferred to Grid is based on the charging state of newlinecoupling capacitor. In order to transfer harvested electrical power to grid, Three newlinePhase, Three Leg inverter is connected between multiport inverter and grid. Fuzzy newlineModel Predictive Control (FMPC) is used to solve the linear and nonlinear control newlineissues in the proposed system. FMPC scheme is suitable for distributed generation newlinesystem for its unique advantages likes reliable, fast and more accurate. In this newlineproposed system, different sources having nonlinear parameters and it s controlled newlineby Fuzzy system. All linear states of three phase grid connected inverters are tested newlineto attain the control objectives. FMPC is proposed to reduce the Total Harmonic newlineDistortion (THD) of the output power. Fuzzy MPPT offers an extremely fast newlinedynamic response with great accuracy. In the proposed system, the inverter control newlinealgorithm is developed using some essential vectors. The aim is to monitor the newlinethree phase grid current and voltage stability and improve the constancy function newlineof the grid-tied inverter during variation of grid voltage. The grid tied inverter is newlinedesigned in two phase standing vector (and#945;and#946;) model, and the FMPC of grid tied newlineinverter is realized during variation of grid current and voltage. MATLAB newlinesimulation is done with different modes, the results shows super capacitor is newlineix newlinedischarging and charging in transient load conditions and mode of operations are newlineperformed based on charge states of coupling capacitor. The transient and steady newlinestate response is analysed using different load conditions with grid current and newlinevoltage variations. The simulation results show the superiority of the FMPC in control strategy. newline newline