【作者】 梁思聪；

【导师】 王维庆；

【作者基本信息】 新疆大学 ， 电力系统及其自动化， 2009， 硕士

【摘要】 750kV凤乌线作为新疆第一条竣工的超高压线路,其试验调试对于最终新疆750kV系统的运行有重要的参考价值。本文依据现有的凤乌线设备参数,构建了凤乌线的计算和仿真模型。对凤乌线在不同运行状态(单端电源空载、两端电源不同负载、不同故障类型)下的工频过电压进行了理论分析,并运用凤乌线的模型进行了计算。针对凤乌线分布参数的特性,按照不同故障类型、跳闸、(重)合闸等操作分类,通过采用T或π型电路模型,对不同运行状态下的凤乌线模型进行了简化。根据简化后的集中参数线路模型,并考虑线路带并联电抗器及状态改变前初始储能的作用,通过拉普拉斯变换对简化电路进行分析,推导得到了其各种操作过电压的近似表达式。本文通过理论分析与大量的EMTDC仿真,总结出凤乌线工频过电压与操作过电压现象的一般规律。对多种运行状态在考虑实际开关特性下的操作过电压倍数,进行了计算汇总。对凤乌线的实际运行有很强的参考意义。最后,本文使用PSCAD/EMTDC软件对凤乌线模型分别进行了空载合闸、线路故障及合闸于永久性故障的仿真,并利用软件中的FFT分析仪对暂态电流的谐波分量进行了分析,并总结了其一般规律;针对上述仿真分析,对暂态电流可能对继电保护造成的影响进行了简要的分析。本文的研究对凤乌线的调试和运行具有重要的参考意义,对其它750kV线路的调试和运行分析也有一定的参考价值。更多还原

【Abstract】 As the first UHV transmission line which had been completed, the test and debugging of the 750kV transmission line—Feng-wu has important reference value to the operation of 750kV system in Xinjiang.In this paper, based on the existing equipment parameters of Feng-wu line, calculation and simulation models have been built. Power frequency over-voltages on different operation state have been theoretically analyzed, which also been computed by using the calculation model.For the characteristics of distributed parameter, according to different fault types, tripping, (re-) closing classifications, such as through the use of T orπ-type circuit model, the line’s models on different operating conditions have been simplified. Under the simplified lumped parameter line model, and to consider lines with shunt reactors and the initial effect of energy storage before the change of state, by the aid of the Laplace transform, the article takes up analysis on the simplified circuit and passes to deduce but got the approximate expression of switching Over-voltage. Through theoretical analysis and a large number of EMTDC simulations, this paper summarizes the general rules of the power frequency over-voltage and switching over-voltage. Furthermore, the multiples of switching over-voltage on various line running states with actual operation characteristics of switch taken into account have been summarized. These have a strong reference value on practical operation of Feng-wu line.Finally, simulations that include line faults, the breaker closing to no-load line and permanent fault are done with PSCAD/EMTDC. The general rules have been found by analyzing the transient current using FFT analyzer. In response to the above simulation analysis, possible influences of Transient current on relay protection have been briefly analyzed.This study is an important reference value to Feng-wu line debugging and running as Well as other 750kV transmission line in Xinjiang更多还原