Design Of Under Well Low Voltage Class Switch Integration Protection System Based On Microcontroller

Mine use separated explosion low voltage switch plays center role in the coal mine power supply system. The capacity of it directly affects the manufacture security of under well and efficiencies. But the intelligence level of low pressure switch mainly depends on the reliability and sensibility of protection controller. Along with rapidly development of coal mine industry, high efficiency, productive coal well construction, the requirement of the continuity of coal well power supply, reliability and security becomes more and more strictly. Hence the study of the coal well low voltage power network integration protection system has very important theoretical and practical values.This project has been demanded by JiYuan high pressured mine switch LTD, and belongs to the new project of JiYuan coal high voltage switch LTD in the low voltage area. This design deeply study the low voltage power network under well, particularly analyze the main problems of selective current leakage, DC leakage detection and short circuit. And it applies the 8bit microcontroller, combined with techniques of power system relay protection and intelligence electronics. Then derive the intelligence integration protection control techniques and protection methods of under well low voltage power network, and apply it into coal well low voltage network. The practical results show that, the proposed protection design is correct, efficiency and practicality.This design of under well low voltage class switch integration protection system based on microcontroller(provisionally named BZD protection equipment), by rule of MT871-2000 the standard,"Mineral product Separates Exploding Low Voltage class Feed Switch",conformed to the specification provided by the Jiyuan coal high-voltage switch Ltd., can detect the error signal, like short circuit, overload, high voltage, low voltage, current leakage etc.,with two key setting and LCD unit.With the advanced study of the different low voltage power supply, the BZD protector preferably solve the problems of fault actions and reject actions of directional power current leakage and makes it working in both neutral point non-grounded and grounded through resistors or coils under compensate systems and over compensate systems.BZD Type protector directly twice sample the AD signal from transducers, and the signal measurement mostly close to true value, and guarantee the accuracy of the detect...