Design And Implementation Of Embedded Power System Multi-function Recorder

With the rapid development of Chinese national economy, the national power grid has formed initially. The trend of power system is expansion of networks and interlink of local area networks, and the performance of power system is more and more complex. Recorder, as a part of recording power system transient state, needs to improve its functions, which can meet the demand of continuously developing power system. The rapid development of computer technologies provide the necessary conditions to improve the performance of recorder, such as global positioning system (GPS), Ethernet, digital signal processor (DSP), embedded system and so on.The development of recorder in our country has made some progress, but compared to overseas development, there are still significant gaps. It will be an important direction of increasing performance of recorder in which computer network and data communications technologies are widely applied. In view of the current problems of domestic recorder, such as small storage capacity, low-rate communications, measuring less channels, a single measurement module, the paper introduces a new design of multi-function recorder, which is based on a dedicated high-performance digital signal processor, a new generation of embedded microprocessor ARM9 and stability of embedded Linux. The system is composed by three subsystems: DSP system, ARM system and host computer interface. The function of DSP system is sampling and transmitting real-time data and recorded data. The function of ARM system is transmission of data, and saving and searching of recorded files. The host computer interface accepts the data, and displays and analyzes them. The paper focuses on the data transmission, storage, searching, and the communication of DSP system and host computer interface. The functions are implemented by multiple threads and Socket technology in embedded Linux. Finally, the functions of the system are debugged and the system is tested. The system basically achieves the design requirements.In the paper, the power system multi-function recorder has several merits, such as strong real-time performance, good scalability, large capacity of data storage, many recording channels, software flexibility, powerful data analysis functions. It will be widely used in the trials of power relay protection system, excitation system and so on.