超高压输电线路的潜供电弧频谱特性

Secondary Arc Spectrum Characteristics on EHV Transmission Lines

超高压输电线路上潜供电弧的存在影响系统的稳定运行。为了对潜供电弧进行系统的研究,采用总谐波失真度来判断电弧的状态,首先应用ATPdraw软件建立潜供电弧的仿真模型,对不同合闸角下故障相电压和潜供电流进行仿真,然后分析其频谱特性和谐波含量,采用傅立叶算法分析得出总谐波失真度。仿真结果表明,在电源电压处于峰值时发生故障,潜供电弧最难熄灭,此时对绝缘造成的危害最大;故障相电压的总谐波失真度在每四分之一周期内随合闸角增大而减小,为利用故障相电压的谐波情况判断电弧状态提供了依据。分析谐波含量频谱特性对实际设计中选择绝缘材料和绝缘结构有一定的指导意义。

On extra-high-voltage （EHV） transmission lines, the existence of secondary arc impacts on the stable operation of system. The effectiveness of single-pole autoreclosure （SPAR） in maintaining power system stability is largely determined by the speed with which secondary arc extinction and autoreclosure can be achieved. So it is necessary to further study secondary arc. One-terminal input data were processed and determined （if and when the secondary arc following clearing of a single-phase-to-ground fault has disappeared. Realistic simulation techniques are of obvious importance in the design of systems employing. We adopted total harmonic distortion （THD） to judge the status of are. First, the simulation model of secondary arc was established by the ATPdraw software. Then, faulted phase voltage and secondary arc were simulated in different close angle. Finally, the spectrum characteristics and harmonic content of faulted phase were analyzed, at the same time. THD was obtained by Fourier algorithm. The simulation results show that THD of faulted phase voltage decreases as close angle in every fourth cycle, providing the basis for judging state of arc by using harmonic content of faulted phase voltage. The analysis of spectrum characteristics of harmonic content is of significance in the design of choosing insulation materials and insulation structure.