Design And Develop Of 10kV-line Microprocessor Protection And Monitoring Device

Distribution network is an important part of the power system, it is responsible for the effective distribution of electric energy. It has very important significance that its safe and stable operation of the entire power system. 10 k V distribution line is the largest number and the most complex structure part of the distribution network. It is essential to install the appropriate microprocessor protection to improve the reliability of power supply of 10 k V distribution lines and to ensure its secure and stable operation. Based on that, the 10 k V-line microprocessor protection and monitoring device is designed and developed.The research profile at home and abroad, requirements and trends of microprocessor protection are reviewed, and the 10 k V microprocessor protection of basic protection principles and protection algorithms are analyzed. The system architecture of 10 k V-line microprocessor protection and monitoring device is introduced, mainly including 10 k V bus, microprocessor protection and monitoring device, circuit breakers, users, and background monitoring processing center.The hardware is designed based on modularization, including four modules, protection module, metering module, human-computer interaction and communication module, and power module. Among them, the high-performance floating-point DSP chip TMS320F28335 is controlling core of protection module, it is responsible for protection logic judgment and protection function realization; the STM32F103VET6 microcontroller is controlling chip of human-computer interaction and communication module to achieve the functions of interface, communications; the ATT7022 B dedicated metering chip of metering module is used to acquire the measurement data;: DC power of the power module is provided by AC-DC switching power, and the required device voltages are provided by the voltage converter circuits.The software design is introduced. The main program is designed in CCS development environment, as well as the associated interruption subroutines, including A/D sampling routine, frequency measurement subroutine, protection judge subroutine, human-computer interaction and communication subroutine. At the same time, the corresponding hardware and software interference immunity are designed to ensure stable and reliable operation of the device.After debugging and testing, the device appropriate protection function can be achieved, its measurement data has been reached the appropriate precision, and the running needs of the power system has been met fully.