Research Of Monitoring And Managing Subsystem For General Protection Of Large Scale Transformer

Large-scale transformer is the hinge of power transmission. Users desire higher capability of monitoring system of transformer protection. In practical applications we usually need to adjust the software and hardware of protection devices, thus affecting the security and reliability of transformer protection. The original monitoring system can't meet the needs of users. They need new monitoring and managing system with more comprehensive function and friendlier human-machine interface.This paper discusses the research and development of general transformer protection. At the first, this paper reviews the history and current status of transformer protection, the actuality and trends of monitoring system are discussed. Then an integrated scheme that using DSP, ARM processor and embedded linux system is presented from the features of general transformer protection. It can be used for extra high voltage transformer's monitoring and managing system. This paper describes the principle and hardware construct in detail, and analyses the function needs of monitoring system, the software construct and the developing environment.The research and development of monitoring function and communication function are the main work of this project. After analyzing the main technique for realizing monitoring system, this paper introduces the method of realizing the embedded linux system, the method of creating index arrays to achieve universal approach of monitoring system, and then expound the concrete realization of QT-based graphic user interface and the management of monitoring system.The developing trend in aspect of network prominent the communication function of microprocessor-based protection. Based on the hardware features the global communication solutions are analyzed. The monitoring system communicates with the protection units by CAN field bus. And it applies the modbus protocol and IEC 60870-5-103 protocol to achieve global communication. The software realization of modbus and IEC 60870-5-103 protocols were described in detail in this paper. General transformer protection equipment has been verified by static simulation experiment. The functions and performance achieved the desired object. This monitoring system has comprehensive monitoring, data record and managing functions. And it has friendly GUI, good stability and security. Finally it is easy to be expanded.Finally the author summaries the work, and gives outlook of this project.