Current mode fuzzy based controller for multilevel inverter

Abstract

Multilevel Inverter (MLI) has come to attention from industries for its practical and convenient solution especially in high power application. It produces staircase voltage waveform which gives more sinusoidal like waveform and as a result it has a lower THD percentage. Through the evolution in MLI topologies and advancement of power electronic devices, it become more viable technology and attracted wide interest for its number of advantages such as above. However, the selection of suitable switching technique to control the MLI has an effective and important role in generating an ideal output voltage that reduce the error as well as the harmonic content. A controller that been introduced into the system must has a characteristic of very fast and responsive, so that it will give more advantage to the MLI. This project will propose and design a current mode fuzzy based controller for five level cascaded multilevel inverter. It is a current mode-based control method offers good performance with faster response as compared to voltage mode control with an expense of additional current sensor. While, the employment of fuzzy control provides a better regulation performance with nonlinear load by manipulating the fuzzy logic structure through heuristic knowledge characteristic of the controller. Hence a system perform with tuneable controller is expected. To validate its performance, a simulation base on MATLAB/SIMULINK® will be conducted with a single phase five-level cascaded multilevel inverter where it been controlled by a proposed fuzzy controller in a current feedback loop. The results of the simulation were observed and analysed.