投切10kV并联电容器的暂态过程研究

发布时间：2018-06-14 16:21

本文选题：并联电容 + 过电压　；参考：《重庆大学》2014年硕士论文

【摘要】：近年来，投切10kV并联电容器的操作事故频发，随着电网结构及负荷变化的日益复杂，故障操作不简单地表现为合闸、分闸操作，而出现了合闸后快速分闸等新故障操作方式，使得过电压的研究更为复杂。本文从实际故障操作特征出发，以理论研究、ATP-EMTP仿真计算和现场试验相结合方式，分别对10kV并联电容器的合闸、分闸、母线侧对地电容变化时分闸、合闸后快速分闸等不同操作暂态过程进行研究，获得了暂态电压、电流的变化规律，推断出各类操作下最为可能故障原因。本论文主要开展了以下工作： ①理论研究了投切10kV并联电容器的暂态过程，分析了各操作暂态过程中电压、电流变化规律，推断出各类操作下最为可能故障原因，研究合闸涌流、高频电流对电弧重燃的激发机制。 ②建立了不同单相、三相仿真模型，对不同操作暂态过程进行仿真研究，获得不同操作暂态特征的仿真性结论：对合闸涌流、高频电流对电弧重燃的激发机制进行仿真性验证。 ③研制了10kV并联电容器操作试验系统，设计多种断路器联动控制方式及控制平台，实现断路器合闸后快速分闸操作、母线侧对地电容变化的实际模拟。 ④对10kV并联电容器进行了合闸、分闸、合闸后快速分闸和母线侧对地电容变化时分闸的现场试验，获得涌流、电弧重燃等不同操作暂态特征的试验性结论，证明母线对地电容变化产生高频电流的可能，对合闸涌流、高频电流对电弧重燃的激发机制进行了试验性验证。综合上述研究得出：合闸涌流、重燃过电压是引发合闸、分闸操作时断路器、电容器故障的最可能原因，合闸涌流、母线对地电容变化产生的高频电流会大大增加重燃概率。研究结论完善了过电压的产生机制，，解释了重大操作事故多发于母线出线少、负荷情况复杂变电站的现状，也为操作过电压的研究提供了一条新的思路，对过电压防护及电气设备绝缘设计等实际生产具有深远的意义。
[Abstract]:In recent years, the operation accidents of switching 10 kV shunt capacitors occur frequently. With the increasing complexity of the power network structure and load change, the fault operation is not simply shown as closing and opening operation, and new fault operation modes such as fast opening after closing have appeared. This makes the study of overvoltage more complicated. Based on the characteristics of practical fault operation and the combination of ATP-EMTP simulation calculation and field test, this paper opens the 10 kV shunt capacitor when the switch, the switch and the busbar side to ground capacitance change, respectively. The transient process of different operation such as fast switching after closing is studied. The variation of transient voltage and current is obtained and the most likely cause of failure is inferred under various operation conditions. The main work of this paper is as follows: 1 the transient process of switched 10 kV shunt capacitor is studied theoretically, and the variation of voltage and current during the transient operation is analyzed, and the most probable fault causes under various operation conditions are inferred. The excitation mechanism of arc reburning caused by closing inrush current and high frequency current is studied. (2) different single-phase and three-phase simulation models are established and the transient processes of different operation are simulated. The simulation results of different operating transient characteristics are as follows: the excitation mechanism of arc reburning caused by closing inrush current and high frequency current is verified by simulation. 3 A 10 kV shunt capacitor operating test system is developed. A variety of circuit breaker linkage control methods and control platform are designed to realize the fast switching operation after the circuit breaker is closed, and the actual simulation of the change of the generatrix side to ground capacitance. 4. The 10 kV shunt capacitor is closed and switched off. In the field test of fast opening after closing and changing of busbar side to ground capacitance, the experimental conclusions of different operating transient characteristics such as inrush current, arc reburning and so on are obtained. It is proved that the change of busbar capacitance to the ground may produce high frequency current, and the inrush current of closing gate can be obtained. The excitation mechanism of arc reburning is experimentally verified by high frequency current. From the above research, it is concluded that the inrush current and reburning overvoltage are the most likely causes of the fault of the circuit breaker and capacitor, the high frequency current caused by the change of the closing inrush current and the change of the busbar capacitance to the ground will greatly increase the probability of reburning. The conclusion of the study consummates the generation mechanism of overvoltage, explains the present situation that the major operation accidents are mostly in the substation with less bus outage and complex load situation, and also provides a new way of thinking for the study of operation overvoltage. It is of great significance for practical production such as protection of overvoltage and insulation design of electrical equipment.
【学位授予单位】：重庆大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM53

【参考文献】