基于功率环解耦的充电桩并网稳定性研究

随着电动汽车的普及发展,充电桩并网稳定性问题亟待解决。文章采用VSG控制方案,首先分析电网电压、频率以及线路阻抗对功率环耦合程度的影响,引入虚拟负阻抗对功率环进行解耦设计,实现功率稳定馈送。同时,在分别设置电网的对称故障和不对称故障两种工况下,进行该控制方案应对主网振荡时稳定运行的可行性研究。基于虚拟负电阻功率环解耦设计的VSG控制方案能够更好地实现电动汽车充电桩稳定并网,提高了其应对主网故障的灵活自控能力。

With the popularization and development of electric vehicles,the stability of charging piles connected to the grid needs to be solved urgently.In this paper,the VSG control scheme is adopted.Firstly,the influence of grid voltage,frequency and line impedance on the coupling degree of the power loop is analyzed,and the virtual negative impedance is introduced to decouple the power loop to realize the power stable feed.At the same time,under the two working conditions of symmetrical fault and asymmetric fault,the control scheme should deal with the feasibility study of stable operation of the main network during oscillation.The VSG control scheme based on the decoupling design of virtual negative resistance power loop can better realize the stable connection of electric vehicle charging piles and improve its flexible self-control ability to deal with main network faults.