风火打捆直流外送系统中极限风电渗透率的计算方法

为在规划时有效评估风火打捆高压直流外送系统的电压稳定性并确定满足电压稳定要求的风电渗透率上限，推导了计及能源基地风火电占比以及本地负荷占比影响的风火打捆直流外送系统的短路比指标。首先，利用PSCAD/EMTDC软件搭建了风火打捆直流孤岛外送系统的电磁暂态仿真模型，通过设置换流母线短路故障，验证了风火孤岛直流外送系统短路比计算公式的正确性。然后，分别设置不同的本地负荷比例、风电渗透率、故障类型以及故障发生位置等情况进行仿真，确定了故障扰动情况下风火孤岛直流外送系统电压失稳所对应的临界短路比。最后，总结提出了适用于远景规划的计算风火打捆孤岛直流外送系统的极限风电渗透率的简易实用的方法。

Calculation Method for Maximum Penetration Ratio of Wind Power in Wind-thermal-bundled HVDC Sending System

In order to effectively evaluate the voltage stability of the wind-thermal-bundled high voltage direct current(HVDC)sending system and determine the upper limit of penetration ratio of wind power that satisfies voltage stability, the short-circuit ratio index of wind-thermal-bundled HVDC sending system is deduced, and the influence of ratios of wind/thermal power and ratios of local load are taken into account. Firstly, the electromagnetic transient simulated model of wind-thermal-bundled HVDC sending system is established by PSCAD/EMTDC. The correctness of the short-circuit ratio formula is verified by setting short-circuit fault of the commutating bus. Then, the simulations are carried out by setting different local load ratios, wind power permeabilities, fault types and fault locations, and the critical short-circuit ratio of wind-thermal-bundled HVDC sending system that meets voltage stability is determined. In the end, a simple and practical method for calculating the maximum penetration ratio of wind power for wind-thermal-bundled island DC sending system which is applicable to long-term planning is summarized.