多端柔性直流输电控制引发的开环模式谐振及其传播

Open-loop Modal Resonance and Propagation of VSC-MTDC With Different Control

针对多端交直流混联电力系统,研究不同直流网控制策略引起的开环模式谐振及其传播方向,发现直流电压下垂控制将增加开环模式谐振的发生概率,扩大谐振的传播范围,对交直流混联电力系统的稳定性产生不利影响。该文建立交直流混联电力系统分别在主从控制、下垂控制等不同直流网控制策略下的闭环线性化模型,分析并揭示开环模式谐振的产生机理和传播特性。然后,评估不同控制策略对交直流混联电力系统小干扰稳定性的影响。最后,以CIGRE5端交直流混联电力系统为例,验证上述分析和结论的正确性,提出消除谐振的参数调节方法。

Open-loop modal resonance and propagation of multi-terminal voltage source converter based HVDC with different control systems was studied based on multi-terminal AC/DC hybrid power system in this paper. Concluded that when the droop control is used, the possibility of open-loop modal resonance will be improved, and the open-loop modal resonance will be more widespread. Specifically, the closed-loop linearized model of multi-terminal AC/DC hybrid power system with different DC network control strategy such as master-slave control and droop control was established. The mechanism and propagation characteristic of Open-loop modal resonance was analyzed and presented. The impact on small signal stability of AC/DC hybrid power system was evaluated. Finally, the correctness of the above analysis and conclusions were verified by taking the multi terminal AC/DC hybrid power system as an example.