并联转移型限流器的研究

发布时间：2018-02-07 12:26

本文关键词： 并联转移弧压值燃弧能量真空介质恢复强度　出处：《沈阳工业大学》2017年硕士论文　论文类型：学位论文

【摘要】：目前我国电力行业迅猛发展,各发电厂的装机容量不断扩大,短路电流容量也快速增长。大功率发电机出口发生短路故障时,最大短路电流值将达10kA以上。传统的限流器不仅很难分断大容量的短路电流,在分断之前发电机或变压器绕组很有可能已经损坏,导致巨大的经济损失。研制新式的短路电流限制器将已成为电力行业的迫切需求。目前为了满足我国市场的需求,一种新型实用并能限制大容量故障短路电流的限流器的研发势在必行,除了会为电力行业的发电厂和变电站带来好处,也可使用在电力系统以外的化工、冶金、舰船及核聚变试验装置等相关的大型电力供应成套设备上,具有很大的研发前景和市场。本文研究的是一种并联转移型的大容量短路故障限流器,应用真空大电流并联转移原理,当大容量短路故障发生时,由主回路真空熔断器先起弧,然后故障短路电流迅速地转移到并联支路高压石英砂熔断器上,最后由其进行分断限流。为确保这种限流器整体结构并联转移的可行性,并最终能够成功可靠地开断大容量故障短路电流,本文首先应用Matlab/Simulink模块建立了故障短路电流并联转移的电路模型,对短路电流并联转移的影响因素进行了仿真分析,还进一步对短路电流的并联转移电路模型进行了修正,得到了可靠的并联转移的动态仿真过程。然后应用Ansys有限元软件对高压石英砂熔断器熔体进行热电耦合的仿真,求不同熔体结构对应的弧前时间。并基于半经验公式对高压石英砂熔断器的熔体进行电弧模型的建立,得到不同结构熔体的总弧压值和燃弧能量值。最后结合试验验证了主回路真空熔断器能否承受住线路总弧压值,达到其真空介质绝缘强度的恢复,不再发生重击穿,最终保证限流器的限流开断成功。通过多次试验结果可以验证,本文所提出的大容量故障短路电流并联转移的模型是正确的,该限流器限制大容量短路电流的策略是可行的。
[Abstract]:At present, with the rapid development of power industry in China, the installed capacity of power plants is expanding, and the short-circuit current capacity is also increasing rapidly. When short-circuit faults occur at the outlet of high-power generators, The maximum short-circuit current value will be more than 10 Ka. Not only is it very difficult for the traditional current limiter to break the short-circuit current of large capacity, but the generator or transformer windings may have been damaged before breaking. The development of a new short-circuit current limiter will become an urgent demand in the power industry. At present, in order to meet the needs of the Chinese market, The development of a new type of practical current limiter that can limit the short-circuit current of a large capacity fault is imperative. In addition to bringing benefits to power plants and substations in the power industry, it can also be used in chemical and metallurgical industries outside the power system. There is a great prospect and market for research and development of large power supply complete sets of equipment related to ship and nuclear fusion test equipment. This paper studies a parallel transfer type large capacity short circuit fault current limiter. Based on the principle of vacuum high current parallel transfer, when a large capacity short circuit fault occurs, the main circuit vacuum fuse starts to arc first, and then the fault short circuit current is quickly transferred to the parallel branch high voltage quartz sand fuse. In order to ensure the feasibility of parallel transfer of the whole structure of the current limiter, and finally to successfully and reliably open the fault short-circuit current of large capacity, In this paper, the circuit model of parallel transfer of fault short-circuit current is established by using Matlab/Simulink module, and the influence factors of shunt transfer of short-circuit current are simulated and analyzed, and the model of shunt transfer circuit of short-circuit current is further modified. A reliable dynamic simulation process of parallel transfer is obtained, and then the thermoelectric coupling simulation of high pressure quartz sand fuse melt is carried out by using Ansys finite element software. Based on the semi-empirical formula, the arc model of high pressure quartz sand fuse was established. The values of total arc voltage and arc burning energy of melt with different structures are obtained. Finally, combined with experiments, it is verified that the main circuit vacuum fuse can withstand the total arc voltage of the line, so that the insulation strength of its vacuum medium can be recovered, and no heavy strike will occur. It is proved by many experiments that the model of parallel transfer of large capacity fault short circuit current proposed in this paper is correct, and the strategy of limiting large capacity short circuit current is feasible.
【学位授予单位】：沈阳工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM471

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