谐波电压造成直流输电换相失败风险评估

Risk Assessment of Commutation Failure for HVDC Transmission Due to Harmonic Voltage

换相失败是高压直流输电(high voltage direct current transmission,HVDC)运行中最常见的故障之一。国内外关于HVDC换相失败的研究已经取得了一些成果,但在谐波对HVDC换相失败的影响研究方面还有待进一步深入。文中从直流输电换相物理过程出发,基于换相电压—时间面积分析推导得出谐波影响因子,然后将谐波影响因子和换相电压—时间面积裕度相结合,定量分析谐波对HVDC换相过程的影响,并给出引起换相失败的谐波电压值理论计算方法;最后,基于PSCAD/EMTDC电磁暂态仿真平台对文中所提评估指标进行了仿真验证。

The commutation failure is one of the most common faults in HVDC(high voltage direct current transmis⁃sion)systems.The research on the HVDC commutation failure caused has made some achievements at home and abroad.However,the influence of harmonic on the failure of HVDC conversion has not been studied thoroughly.Based on the commutation process of HVDC transmission,the harmonic influence factor is derived based on the com⁃mutation voltage⁃time area analysis.Then,the harmonic influence factor is combined with the commutation voltage⁃time area margin.The influence of harmonics on the commutation process of HVDC is quantitatively analyzed,and the theoretical calculation method of the harmonic voltage value causing the commutation failure is given.Finally,based on the PSCAD/EMTDC electromagnetic transient simulation platform,the evaluation indicators proposed in this paper are simulated and verified.