A Transformer Less High Step up DC-DC Converter Based on Cockcroft Walton Voltage Multiplier for Grid Tied System

Abstract

In this project, a transformer less high step-up DC-DC converter based on Cockcroft Walton voltage multiplier is proposed. Normally batteries, fuel stacks, solar cells are operated at low voltages. In order to connect grid tied systems, there should be a high voltage gain and low voltage stress on the switches, diodes and capacitors. For an n-stage Cockcroft Walton voltage multiplier, the proposed converter can provide suitable dc source for n+1 level multi-level inverter. In this project, the proposed control strategy employs two different frequencies; one is operated at high frequency in order to reduce size of the inductor, while the other is operated at low frequency according to the desired output voltage.