Fractional Order Modified AWPI Based DC-DC Converter Controlled SEDC Motor

Abstract

AbstractIn this paper, a fractional order modified Anti Windup (AW) proportional–integral (PI) scheme is designed to generate the switching gate pulse of buck converter to control the speed of separately excited DC (SEDC) motor for low speed applications. Input saturation is a constraint on all real-time motors. Furthermore, for DC-DC power converters, the duty cycle is the natural control input. Therefore, to keep off the wind up phenomena, the output of a new modified fractional order back calculation-based AW scheme with PI controller is compared to the repetitive sawtooth waveform for switching pulse generation in closed loop speed tracking system. Here, fractional tuning gain of integrator contributes additional flexibility. To ameliorate the steady state error as well as tracking speed performance compared to the AWPI and fractional order AWPI controller, this new controller is formulated by taking the difference between AW tracking time constant and proportional gain connected to the output capacitor voltage signal. It can be observed that the new controller, with its two configurable parameters, outperforms in terms of speed tracking. Also, it can minimize the integral time absolute error (ITAE) and integral squared error (ISE). In presence of noise, both fractional order controllers perform well compared to the integer order controller by showing their potency for speed tracking as well as disturbance rejection.KeywordsFractional order modified AWPI controllerDC-DC Buck converterSEDC motor