特高压直流送端近区风机暂态过电压实测与分析

Measurement and Analysis of Transient Overvoltage of the Wind Turbines in the Near-zone of the Ultra High Voltage Direct Current Sending End

直流系统功率扰动引起送端近区风电暂态过电压,已成为限制祁韶直流输送能力提升的约束故障。为此,首先分析了直流功率扰动引起风机暂态过电压的机理,然后开展了大扰动后的祁韶直流近区风机暂态压升实测试验,并与基于PSASP的仿真分析结果进行了对比研究。从挖掘风电场自身无功调控能力入手,提出了提升故障后风机有功恢复速率、优化风机和无功补偿装置的暂态无功响应控制策略、提升风机暂态过电压耐受能力等抑制风机暂态压升的措施。最后通过算例仿真证明了措施的有效性。上述措施可实施、可复制和可推广,具有很强的工程应用价值。

Transient wind power over-voltage in the near-zone of the ultra high voltage direct current(UHVDC) sending end caused by power disturbance of the DC system has become a constraint limiting the increase of DC transmission capacity in Qishao. To solve this problem, firstly, the mechanism of transient overvoltage of wind turbines caused by DC power disturbance was analyzed. Then, transient voltage rise of the generator after serious disturbance in the DC near-zone in Qishao was actually measured and compared with the result of PSASP-based simulation analysis. Starting from exploiting the reactive control capability of the wind farm, measures for suppressing transient voltage rise of the generator were proposed, such as increase of active recovery rate of the machine after failure, optimization of reactive response control strategy for the wind turbines and reactive power compensation devices, as well as improvement of transient overvoltage tolerance of the machine. Finally, the validity of the proposed measures was proved through example simulation. The above measures were implementable, reproducible and expandable, and had high engineering application values.