含调谐网络的半波长输电系统特性分析

发布时间：2018-06-15 19:53

本文选题：电力系统 + 半波长输电　；参考：《哈尔滨工业大学》2017年硕士论文

【摘要】：当前,我国西部能源中心与东部负荷中心之间的距离可能达到甚至超过3000km,国际上远距离输电的计划也越来越多。远距离、大容量的输电技术亟待研究。半波长交流输电技术作为一种超远距离输电模式,对其研究有着重要的意义。基于长输电线路模型,详细分析了均匀和非均匀输电线路的输电特性。在不同功率下,给出了均匀输电线路沿线电压电流幅值极值出现的位置及大小的数学表达式。对于非均匀输电线路,提出了其满足半波长输电特性的一个充分条件。为分析半波长输电系统的暂态特性,基于半波长的集总参数模型,利用分裂法理论,建立了用于数值仿真的半波长输电线路离散等值动态模型,该模型具有结构简单、数值仿真稳定性好、精度高的特点。利用该模型,对半波长输电系统的空载合闸、甩负荷、单相接地故障进行了仿真。当均匀输电线路不足半波长时,详细地研究了其调谐网络的类型及其参数确定方法。基于均匀传输线的传输参数矩阵,给出了T型、π型和电容型调谐网络的参数确定方法。在稳态情况下,利用电容型调谐网络补偿线路长度时,减小了等效特征阻抗、增大了等效自然功率。在稳态情况下,利用T型或π型调谐网络补偿线路长度时,其等效特征阻抗和等效自然功率均不变。详细分析了电容型调谐网络个数及T型和π型调谐网络安装位置对首末端电压比、线路损耗和沿线电压分布的影响。对于非均匀的传输线,给出了其调谐网络结构,并基于传输线的传输参数矩阵,给出了其参数确定方法。对于含有调谐网络的半波长输电线路,仿真分析了含有π型和电容型调谐网络的暂态特性,含有电容型调谐网络的系统暂态过电压要小于含有π型调谐网络的系统,分析了电容型调谐网络个数、首端母线处故障电流和线路长度对暂态过程的影响。对于π型和电容型调谐网络内部电容两端暂态电压过高的问题,给出了降低方法。经仿真分析,提出的π型和电容型调谐网络中性点经电阻接地的方法,可有效抑制其电容两端的暂态过电压。
[Abstract]:At present, the distance between the western energy center and the eastern load center may reach or even exceed the 3000km. There are more and more plans for the long distance transmission in the world. The long distance, large capacity transmission technology needs to be studied urgently. Half wavelength AC transmission technology is of great significance to its research as a super distance transmission mode. In the long transmission line model, the transmission characteristics of uniform and non-uniform transmission lines are analyzed in detail. At different power, the mathematical expressions of the position and size of the extreme value of the voltage and current amplitude along the uniform transmission line are given. A sufficient condition for the non uniform transmission lines to meet the half wavelength transmission characteristics is proposed. The transient characteristics of the half wavelength transmission system are analyzed. Based on the half wavelength lumped parameter model, the discrete equivalent dynamic model for the semi wavelength transmission line is established by using the split method theory. The model has a simple structure, good numerical simulation stability and high precision. Using this model, the space load of half wavelength transmission system is unloaded. Sluice, load rejection and single-phase grounding fault are simulated. When a uniform transmission line is less than half wavelength, the type of tuning network and its parameter determination method are studied in detail. Based on the transmission parameter matrix of uniform transmission line, the parameter determination method of T, PI and capacitive type tuning networks is given. When the tuning network compensates the length of the line, the equivalent characteristic impedance is reduced and the equivalent natural power is increased. In the steady state, the equivalent characteristic impedance and the equivalent natural power are invariable when the T type or PI tuning network compensates the line length. The number of capacitance tuned network collaterals and the installation position of the T and PI tuning networks are analyzed in detail. The influence of the first terminal voltage ratio, the line loss and the distribution of the voltage along the line. For the non-uniform transmission line, the tuning network structure is given, and the parameter determination method is given based on the transmission line transmission parameter matrix. For the half wavelength transmission line containing the tunable network, the pion type and the capacitive tuning network are analyzed. The transient overvoltage of a system containing a capacitive tuning network is less than a system containing a pion tuned network. The effects of the number of capacitance tuning networks, the fault current and the length of the first bus line on the transient process are analyzed. The problem of the transient overvoltage at both ends of the internal capacitance of the pion and capacitive tunable network is given. The method of reducing the transient overvoltage at both ends of the capacitor can be effectively suppressed by the simulation analysis.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM75

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