Active Damping Control Strategy for Bus Voltage of Special Vehicle Based on Virtual Resistance

In the power system of special vehicles, the proportion of constant power load Constant Power Load (CPL) increases, and its negative impedance characteristics cause the oscillation of bus voltage, this paper proposes a virtual resistor active damping control strategy based on droop control. Firstly, the equivalent model of the structure of DC microgrid and the equivalent model of CPL are analyzed, and then a virtual resistance strategy suitable for Boost converter is proposed. In addition, a nonlinear disturbance observer (NDO) is designed to achieve fast tracking of disturbances in the system without adding additional current sensors, and the nonlinear disturbance observer is used to get rid of the strong dependence of the control algorithm on the output current sensor. The combination of NDO and virtual resistance control improves the load compensation capability of the control strategy and eliminates the voltage deviation caused by droop control through voltage compensation. Finally, use MATLAB /Simulink to verify the effectiveness of the proposed control algorithm.