不对称参数同杆并架双回线故障选相和测距方法的研究

发布时间：2018-09-11 06:11

【摘要】：同杆并架双回线可以有效提升线路单位走廊的输电效率,降低输电的成本,近年来已逐渐取代单回线成为主要的输电线路。由于同杆并架线路双回线之间的距离较近,不仅存在相间互感,相邻两线之间也会存在互感,其故障类型也更为复杂,这使得同杆并架双回线的故障选相和故障测距存在一定的难度。现在较多在六序分量法的基础上对双回线进行故障选相和故障测距,但是由于六序分量法并不适用于参数不对称的同杆双回线,所以深入开展不对称参数同杆双回线的故障选相和测距方法的研究,对于保证电网运行的稳定性具有重要的理论和现实意义。本文在新的解耦方法的基础上提出了针对不对称参数同杆双回线的故障选相和测距方法。当线路发生故障时,可以根据故障边界条件得到序分量之间的幅值和相位关系。不同线路发生故障时,两回线正序分量的电流幅值不同;同一回线发生不同类型的故障时,序电流分量的幅值有对应的关系;同一类型的不同相发生故障时,序分量的相位不同。可以根据上述关系确定单回线故障时相应的选相判据,并给出了选相流程。通过采集线路两端故障前后的相电压和电流值,利用新的解耦方法得到序电压和序电流,根据从两端计算的故障点的序电压相等这一性质,获得测距方程从而进行故障测距。并针对一种特殊的非全程同杆双回线路进行研究,提出故障测距方法。根据PSCAD仿真结果表明,该选相和测距方法均比较准确,而且不受故障类型,故障位置和过渡电阻等因素的影响。
[Abstract]:In recent years, the single circuit line has been gradually replaced by the single circuit line as the main transmission line, which can effectively improve the transmission efficiency and reduce the transmission cost of the unit corridor. Due to the close distance between the double circuit lines of the same line, there is not only mutual inductance between phases, but also mutual inductance between adjacent two lines, and the fault type is more complex. This makes the fault phase selection and fault location of the double circuit line of the same pole and frame have some difficulty. At present, the fault phase selection and fault location of double-circuit lines are mostly carried out on the basis of six-sequence component method. However, the six-sequence component method is not suitable for double-circuit lines with asymmetric parameters. Therefore, it is of great theoretical and practical significance to deeply study the fault phase selection and location method for asymmetric double-circuit lines with the same pole and pole, which is of great theoretical and practical significance to ensure the stability of power network operation. Based on the new decoupling method, this paper presents a fault phase selection and location method for the asymmetrical parameters of the same rod double circuit line. The amplitude and phase relationship between the sequence components can be obtained according to the fault boundary condition when the fault occurs. When different lines fail, the amplitude of positive sequence component of two circuit lines is different; when different types of faults occur on the same circuit, the amplitude of sequence current component has a corresponding relationship; when the same type of fault occurs in different phases, the amplitude of sequence current component has a corresponding relationship. The phase of the sequence component is different. According to the above relation, the phase selection criterion for single circuit fault can be determined, and the flow chart of phase selection is given. By collecting the phase voltage and current value before and after the fault at both ends of the line, the sequence voltage and sequence current are obtained by using the new decoupling method. According to the property that the sequence voltage of the fault point calculated from both ends is equal, the fault location equation is obtained and the fault location equation is obtained. A fault location method is proposed for a special non-whole-range dual-circuit. The results of PSCAD simulation show that the phase selection and location method are accurate and are not affected by fault type, fault location and transition resistance.
【学位授予单位】：南京理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM75

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