The Design Of The Switching Value And The Gas Detection System Of Digital Substation

Digital substation means that the collection,transmission,processing,output process of the information in the substation are all digitized.The first electric equipment and the second electronic devices in substation are digital communication,unified with data model and data communication platform.In this platform the interoperability between intelligent devices comes true.Because the digital substation has the incomparable advantage,the digital substation becomes the hot spot of the new technology development of substation.In this thesis,design a detect system for the 110kV voltage class digital substation which uses the PASS system as the first electric equipment.After the pressure and temperature detection signal of SF6 gas,isolating switch position signal,circuit breaker position signal and grounding switch position signal in the process layer do pretreatment and convert into light signals through the sensor and transmission mechanism PISA,these signals will be send into the spacing layer through the detect system interface.In the spacing layer use the combination unit and embedded system ARM to arrange these signals,and connect the protection and monitoring system of the substation through IEC61850.The main works of the thesis includes the following aspects:Firstly,SF6 gas temperature and pressure detection signal processing unit and the upper data receiving chip interface are designed.Secondly,the switch value and upper receiver chip interface are designed;including hardware circuit design(the analog part,digital part and other hardware interface circuit) and the hardware logic design of system programmable logic device,which uses VHDL language for the logic design of the CPLD.By debugging and testing the detect system,it realized the measurement data sampling and receiving very good.The system is debugged easily and low-complexity,has good flexibility in hardware.