Active Disturbance rejection Hopf bifurcation suppression strategy based on DC microgrid DC-DC converter

Abstract

To solve the problem that the output voltage of the Buck converter is easily affected by the change of system parameters, which reduces the energy transmission quality, a linear active disturbance rejection control strategy is proposed in this paper. Firstly, a discrete mathematical model is established to analyze that Hopf bifurcation disturbance is the cause of low-frequency oscillation of output voltage, and the existence of Hopf bifurcation disturbance is verified by simulation. Secondly, based on the theoretical analysis, the suppression effect of improving the error feedback control rate on Hopf bifurcation disturbance is designed. Moreover, the stability of the control strategy under Hopf bifurcation disturbance is analyzed by using frequency-domain theory. Finally, the suppression of Hopf bifurcation disturbance by the proposed control strategy and the traditional PI control strategy under different working conditions is compared by simulation analysis. The results show that the proposed linear active disturbance rejection control strategy can effectively suppress Hopf bifurcation disturbance and guarantee the performance of the Buck converter.