Design And Research Of Relay Protection Scheme For Power Supply System In Fetian Coal Mine

The stable operation of mine power supply system is an important premise of mine safety production,and relay protection plays a vital role in the safe operation of mine power supply system.Due to short circuit in the power supply system of Feitian coal mine,grade-jumping tripping occurs frequently,which seriously affects the safety and stability of the power supply system and endangers the life safety of underground operators.For fields of coal mine power supply system of large area blackout accident caused by short circuit fault,combined with the fertile field distribution in the system of coal mine power supply series,short power lines and underground environment more bad,etc,we design a type S3C2440AL chip based hardware optical differential protection device,in order to improve the power supply system above the tripping protection device,went to avoid short-circuit trip,safe and reliable power supply system is improved.Fertile field of coal mine power supply system,the author of this paper is selective differential relay protection,great frequent tripping problems,mainly studied the power system relay protection,at the same time to against the existing problems of relay protection schemes are analyzed,and the optical fiber current differential protection,current data sampling synchronization,theory of optical fiber communication system are expounded and analyzed,based on the above theory research and the problem analysis,the whole power supply system as the research object went against tripping protection system,through the analysis of a variety of optical fiber communication mode,the design is suitable for the fields of coal mine power supply system of the special fiber channel,The problem that the sampling time adjustment method is greatly affected by channel change is improved.Finally,based on ARM9 series chip and embedded C/OS-? operating system,the design of hardware and software for the fiber longitudinal differential protection against overstep trip is carried out.The hardware part includes the design of the minimum system and functional modules,and the software part includes the protection main program,data acquisition program,communication program,fault processing program and human-computer interaction program.In this paper,the software and hardware design of mine skip prevention tripping protection device is completed,and the reliable mine optical fiber communication scheme is designed.Meanwhile,targeted optimization work is carried out for the traditional time synchronization scheme and sampling algorithm.The functional test results show that the mine level protection system designed in this paper can effectively complete the protection action,which has certain reference significance in the mine power supply system.