基于虚拟导纳的构网型变流器功率振荡抑制方法OA

Grid-forming converters exhibit voltage-source characteristics and can provide damping and frequency support for modern power systems,however,they face stability issues when connected to low impedance grids.To address this problem,this paper proposes a power oscillation suppression method based on virtual admittance.First,a small signal model of a grid-forming converter integrated into an AC grid is established.Then,a stability control strategy based on virtual admittance is designed which can enhance system stability by compensating the input current of the current control loop.The effectiveness of the proposed method in improving grid-connection stability is verified through eigenvalue analysis.Furthermore,the dynamics characteristics of the system under different operating conditions before and after applying the virtual admittance control are thoroughly analyzed,and the influence of virtual admittance control parameters on system stability is also investigated,providing a basis for parameter optimization.Finally,time-domain simulations are conducted using a MATLAB/Simulink based grid-connected model,and hardware-in-the-loop validation is performed on a real-time experimental platform.The results demonstrate that the proposed virtual admittance control method can effectively suppress power oscillations of the grid-forming converters in low impedance grids.