【作者】 龚震东；

【导师】 范春菊；

【作者基本信息】 上海交通大学 ， 电力系统及其自动化， 2008， 硕士

【摘要】 随着实际需求和电力系统的发展,同杆多回线因其能更好地解决走廊宽度不够以及大功率输送的问题,在高压输配电工程中得到日益广泛的应用。同杆多回线包括应用较为广泛的同杆双回线和目前正在建造的同杆四回线等。其特点是输电负荷重,一旦故障亟需准确定位以快速排除故障。而事实上多回线的线间耦合这一特点给这类故障定位造成相当的难度:同杆双回线的故障定位已经有较多研究,但是多需要双端数据,而缺少精确的基于单端数据的测距方案。同杆四回线的研究更是缺少统一的故障分析方法和模型,测距研究也受到限制。针对上述问题,本文一方面给出了一种基于单端数据的同杆双回线精确测距方法。另一方面重点对多回线中的同杆四回线的线间耦合问题进行了详尽的研究,使用矩阵变换将耦合的线路进行解耦,形成相互独立的十二序分量,从而创造性地提出了针对同杆四回线的故障分析方法——同杆四回线的12序分量法。本文还详细研究了这十二序分量的特点,并给出了线路发生故障时的各序分量图。十二序分量法不仅可以成为同杆四回线故障计算的基本方法,还为同杆四回线的故障测距和保护配置打下理论基础。大量的EMTP仿真结果表明十二序分量法的精确性及各项图表的正确性。本文使用12序分量法对同杆四回线进行故障测距,提出了基于反序电流的同杆四回线的故障测距方法,该方法具有极高的测距精度。大量仿真试验表明本文所提出12序分量法能够对四回线进行有效解耦,物理意义明确,能够应用于故障测距等分析。文中的双回线单端测距方法和四回线测距的精度不受故障类型的影响,与过渡电阻无关,并且不受系统运行方式和电源相位差的影响,测距结果精度高。更多还原

【Abstract】 An accurate fault locator makes it possible for fast restoration and availability of the power system, especially in increasing complex modern power transmission systems. Multi-parallel transmission lines are widely used in power system today, and on the other hand, frequently subject a variety of technical problems in the view of protection engineering. These problems are mainly due to the mutual coupling between lines, which requires decoupling between lines on the same tower.In this paper, a new one-terminal fault location algorithm for parallel transmission line is introduced. Then twelve-sequence component method is introduced in this paper to decouple mutual electromagnetic effect between the four lines. The twelve -sequence components are independent from each other. The characteristic of the twelve-sequence components is studied and the related sequence networks are introduced. The twelve-sequence component method can not only be the basic method of the fault analysis but also the basic theory of the fault location and relay protection for the four-parallel lines. Based on the twelve-sequence component method a location algorithm for four-parallel lines is introduced which is independent of source impedance, fault type, fault resistance and mutual coupling between four-parallel lines. A lot of results of EMTP simulation indicate that the twelve-sequence component method is correct and valid for fault analysis. All the algorithms have been tested by EMTP simulations, which indicate high accuracy under various fault conditions.更多还原