Design Strategies and Performance Comparison Of Software & Hardware Damping of Resonance Spike

Abstract

Compared with the traditional L-type filter, the LCL filter can better suppress the switching harmonics of the PWM rectifier. However, it is additional high-frequency resonance spikes will also have a certain effect on system stability. Common strategies for damping resonance spikes are divided into hardware damping and software damping. As for passive hardware damping, this paper expands the design based on the typical parameters of the capacitor parallel resistance method in the wind power application scenario and summarizes and proposes general resistance parameter determination methods. As for the software virtual resistance damping, the virtual resistance is constructed based on the vector control method, and the resonance peak damping of the three-phase LCL rectifier is performed. The negative damping caused by the control delay is solved by adding a lead-lag link. Simulation results verify the feasibility of the method. Finally, a comprehensive analysis and comparison of the software/hardware strategies for the damped resonance spikes of the LCL converter are made, and the conclusions are verified by simulation.