International Journal of Engineering Research

Abstract

Presently in the grid, twelve inverters followed by twelve transformers of 720/415V have been used. This combination results in very less efficiency of the existing plant. In this paper, a prototype of single phase grid connected transformerless inverter is designed to overcome the problems associated by their combination.

From solar panel of 720V DC output is given to Buck converter which further reduces the output to 415V DC. Buck converter is followed by single phase inverter of 250 kW. The inverter topology is a full bridge inverter with addition of two more switches after the input stage. High efficiency of this proposed inverter is achieved by using Unipolar Sinusoidal Pulse Width Modulation switching strategy.

Keywords

Full Text

Abstract

A 3x3 matrix converter is a direct ac to ac converter uses a matrix of semiconductor bidirectional switches, with a switch connected between each input terminal to each output terminal. With proper arrangement of switches, the power flow through the converter can be reversed. Since energy storage element is absent here, so the instantaneous input power must be equal to the output power assuming zero loss switches. The switching functions while operating such a converter must ensure that, the switches do not short circuit the voltage sources and do not open circuit the current sources. Pulsing these nine switches according to an appropriate pattern, the necessary amplitude modulation and frequency conversion for the output voltage are achieved with simultaneous control of input displacement factor.

This paper describes a detailed study for the generation of the desired switching pulses for the 3x3 Matrix Converter. For this, the duty cycle calculation and gate signal generation for the nine bidirectional switches of Matrix converter, MATLAB, SIMULINK has been used.

Keywords

Full Text