The Reasearch And Design Of Unlock Key Management Box For Substation

At present the unlock key of subsation is in poor management , facing this new case, a new management box for unlock key is proposed in this paper ,which realizes scientific management of the unlock key, and provides an effective assurance for substation's safe operation. It controls the swith of the box by receiving and sending short message through GSM.Basic principle and technology related to the design of management box are discussed in this paper, including GSM, AT instruction and process of coding and decoding of short message. Besides, the related provisions of The State Grid about the use of the unlock key and the requirements of substation on the use of unlock key are specially introduced in detail.This paper mainly designs the hardware electrocircuit, including monitor unit, MC37i unit and its corresponding external interface circuits, opening door circuit and power supply circuit. Finally, the whole principle chart and the PCB board is protracted.ATmega8L made by ATMEL company is taken as main control chip, designing the corresponding external interface circuits. The control chip receives short message from Management center and authorised phone through using GSM module of Siemens company, then executes"open the door"instructions. The usage record will be saved automatically after the management box of unlock key is back and be sended to Management center at the same time. When the monitor module detects the state of the management box door or unlock key are unusual, the SCM will send alarm message to Management center through MC37i module. Then scientific management of the unlock key management will be realized.The application of short message techniques not only has solved inconvenience caused by time and places, and can carry out unlock operation in time to minimize the damage caused by misoperations, but also has made the unattended substation practical which increases substation economic benefit.