面向电网规划的多馈入直流换相失败功率冲击模拟方法

多直流馈入受端电网的交直流、多直流耦合交互特性显著,由交流故障引发的多回直流换相失败问题已经成为影响受端电网安全稳定运行的关键约束。但在电网规划阶段,因缺乏直流工程的实际参数,相关部门仍采用CIGRE推荐的准稳态简化模型开展电网安全稳定分析计算,获取的直流换相失败对交流电网的功率冲击特性严重偏离实际情况。在综合考虑直流近区无功支撑能力对换相失败恢复的影响,并计及因多馈入直流间交互作用导致的非换相失败直流功率扰动基础上,提出一种提高多馈入直流换相失败对交流电网功率冲击模拟精度的仿真方法。实际多馈入直流受端系统的仿真算例验证了该方法的有效性。

Simulation Method of Power Impact Caused by Multi-infeed HVDC Commutation Failure for Power Grid Planning

The coupling interaction of AC-DC and DC-DC in the multi-infeed HVDC receiving-end power grid is so manifest that the commutation failure of multi-infeed HVDC caused by AC power system fault has become the key constraint to the security and stability of the receiving-end power grid. However, during the power grid planning stage, for lack of actual parameters of HVDC project, the concerned departments are still using recommended simplified quasi-steady-state model by CIGRE to carry out the safety and stability simulation analysis. The characteristics of power impact caused by HVDC commutation failure seriously deviate from the actual situation. The influence of reactive power supporting capability to HVDC commutation failure recovery is considered in the near-field, and the non-commutation failure HVDC power perturbation caused by multi-infeed HVDC interaction is taken into account. An improved method for multi-infeed HVDC power grid to accurately simulate the power impact on AC power system is proposed. The simulation results of actual power grid verify the effectiveness of the method.