Design Of Protective Relay System Based On Arm+μc/os-ⅱ

With the rapid development of national economy, the scale of power system becomes larger and larger, and its structure gets more and more complicated. Because of the influence of man-made or nature factors, some faults results in the system out of action, which always happens. Therefore, it is an important task to guarantee the electric power system runs in safe reliability, and improve the quality of power energy. The relay protection system is an automation system that can detect the fault and deviant state of electric power system, and drive the breaker's action or send out the alarm message. The role of protection relay system is to cut the fault module in automatically and rapidly so as to avoid destroying system.The paper explores the technology renovation of microcomputer protection device, which adopts new hardware and embedded real-time operating system. 32 bit microprocessor are adept to hardware system S3C2410 produced by SAMSUNG company, also attached rich peripheral circuits. The software platform is based on strongly functional and embedded operating systemμC/OS-II, theμC/OS-II is transplanted to the targeted hardware S3C2410 so as to process the design of microcomputer protection application software based onμC/OS-II. In order to meet the digital substation,automation,artificial intelligence and network development requirements.This paper describes the protection and the basic algorithm principles against the 110kv line configuration.AMR9 as the core hardware circuit design is elaborated in detail, including power circuit, clock circuits, data acquisition circuit, CPLD circuit, JTAG circuit and so on. Especially data acquisition circuit which adopts high speed 32bits S3C2410 and 16bits high accurate AD7656 as hardware platform, which advances the device's speed and accuracy .Moreover, this system uses CPLD instead of traditional and separate logic device ,which advances reliability and anti-jamming performance of the device.In software side, to transplant operating systemμC/OS-II on ARM9 successfully. In considering the condition that linkages between the task and priority case, it introduces the partition and design of task on the application microcomputer procedures based onμC/OS-II platform. Finally, we designed the FFT in microcomputer protection procedures and data Acquisition procedures, moreover, it is given the debugging results in the ADS environment and real-time display of waveform sampling by LCD. The result shows that both the device and hardware meet the designed requirements, which can satisfy the needs of practical engineering in the power system.