Abstract: MATLAB Simulink is a commercial tool developed by the Math Work Inc. Under the MATLAB family for modelling, simulating and analysing multi domain dynamic systems. In this paper simulation of different chopper circuits are done. Dc Chopper finds tremendous applications indrives and control. The variable resistance is commonly used in series with the armature of the DC motor for speed control can be replaced by a chopper resulting in better efficiency. Therefore it can be utilized in battery-operated vehicles and in applications where saving of energy is a prime consideration. Operation of various choppers in four quadrant had been simulated by using Matlab in this paper.

Keywords: Dc Chopper, Matlab, four quadrant, Simulink.