Comparative investigation on the dynamic behaviours of SRD operated under PI control strategies

In this paper, by making use of Fourier series, mathematic description of a four-phase switched reluctance drive (SRD) system with proportional-integral (PI) control is presented based on the equivalent non-linear inductance function. The PI control strategy is carried out under digital and analogous modes, respectively. After addressing the waveforms of system output variables, the bifurcation characteristics of digitally controlled SRD are discussed comparatively with its analogously controlled counterpart to highlight the differences between digital and analogous control strategies. Lastly, the experimental results are provided to further verify the correctness of the theoretical analysis.