长距离输电线路并联电抗器布置对功率传输的影响

Effect of Shunt Reactor Placement on Power Transfer in Long Transmission Lines

为了研究长距离交流输电线路上并联电抗器布置对功率传输的影响,基于长距离超、特高压输电线路分布参数等效电路及二端口模型,分析了传输线路的最大传输功率及最大传输效率,推导了串补条件下两种并联电抗器布置方案的级联传输矩阵。采用500 k V、1 100 k V线路典型参数,针对并联电抗器布置对最大传输功率与最大传输效率的影响进行数值模拟分析。研究结果表明并联电抗器位置在发送端与中点串补电容之间或者接收端与中点串补电容之间变化时,最大传输功率与最大传输效率均随其位置变化而发生变化。同时,并联电抗器补偿度也会影响功率传输,随着并联电抗器补偿度的增加最大传输功率及最大传输效率均会降低。

In order to study the influence of shunt reactor placement on power transfer in long transmission lines, the maximum power transfer and maximum efficiency of transmission are analyzed mathematically based on the equivalent circuit of distributed parameters and two-port model of long extra high voltage（EHV）/ultra high voltage（UHV） transmission lines. And the cascaded matrices on placement schemes of controllable shunt reactor with series capacitor compensation are derived. Then the effect of shunt reactor placement on maximum power transfer and maximum efficiency of transmission are studied numerically with the aid of some typical data of 500 kV and 1100 kV transmission lines. The results of mathematical analysis and simulation show that maximum power transfer and maximum efficiency of transmission will vary continuously with the location of shunt reactor when it is located between sending or receiving end and the center series capacitor. Furthermore, the power transfer is also affected by the compensation degree of shunt reactor, and the maximum power transfer and maximum efficiency of transmission will decrease with the increase in compensation degree.