Performance Investigation of PI Controller Based Chopper Fed DC Drive

Abstract

The idea orients to develop a PI controller for closed loop speed control of chopper fed dc drive. PI controller is one of the most preferred controller for speed control of dc drive, which can be easily understood and implemented in practice. The speed of the chopper fed separately excited dc motor can be regulated from below and upto rated speed by using a chopper as a converter. The signal corresponding to the speed error of the motor and change in speed error are given as inputs to the PI controller. The controller output provides the required gating signal that is used to vary the duty cycle of chopper. The chopper firing circuit receives signal from controller, gives variable voltage to the armature of the motor for achieving desired speed response. Modeling of chopper fed dc motor is done. Two loop control system is designed, one for current and another for speed. The complete model of proposed system is simulated using MATLAB (SIMULINK). Also the performance of the simulated model is investigated by using various controller tuning methods.

Implementation of Chopper Fed Speed Control of Separately Excited DC Motor Using PI Controller

“…The power semiconductor devices used for a chopper circuit can be force commutated thyristor, power BJT, MOSFET, IGBT and GTO based chopper are used. It having very low switching losses that means total voltage drop has 0.5V to 2.5V across them [8]. The various controllers that can be used in speed control operation are available.…”