PLC低电压闭锁过电流保护设计.doc

摘 要 中国的电力工业作为国家最重要的能源工业，一直处于优先发展的地位，电力企业的发展也是令人瞩目的。电力系统的飞速发展对继电保护不断提出新的要求，也使得继电保护得以飞速的发展。 保护是继电保护中一种重要的保护形式。本文在详细研究了保护的各种元件与接线方式，按照整定计算原则推导了护的动作值、灵敏度及时限整定公式等，35kV单端电源供电网络的保护的整定计算，最后利用技术进行。 本文叙述了基于PLC来设计低电压闭锁过电流保护。在设计过程中，需要以传统继电保护为基础来计算出线路的短路电流，通过对线路的整定计算和灵敏度校验来设计出其原理图并选出保护装置和设备，再利用原理图画出展开图、I/O表和输入输出端子接线图，最后根据上述结论绘制梯形图并写出指令语句表。本文所研究的保护是一种比较理想的线路保护。它能够使各段保护相互配合，以使保护性能达到最优。 关键词 继电保护保护 整定计算 Abstract Chinas power industry as the countrys most important energy industry, has been in priority development of status, the development of the electric power enterprise is remarkable. The rapid development of electric power system of relay protection continuously put forward new requirements, but also makes the relay protection to rapid development. Low voltage artesian over-current protection is an important relay protection of the protection form. Based on the detailed research on low voltage artesian over current protection of various components and the wiring way, according to the principle of setting calculation is deduced and the low voltage artesian over current protection action value, sensitivity calibration and time limit, such as setting formula, and by mathematical tool software programming, simulated 35kV one-port power supply network of low voltage artesian over-current protection setting calculation, finally, using the PLC technology for programming. Strives to be reliable operation, simple, convenient, economy reasonable, and has expanded the possibility and change operation mode flexibility. Make it more real, more realistic significance joint. This paper describe PLC-based to design the protection of low voltage artesian over-current protection and setting calculation. In the design process, it requires to calculate the short-circuit current of 10kv overhead lines based on the conventional protection of relay ,design its schematic and select protective device and equipment by setting calculation of line and sensitivity check, then u