Research And Development Of The 110kV Microprocessor Transmission Line Protection Device Based On DSP

With the increasing scale of electric power system and the rapid development of high voltage power grid ,there are higher standard requirements about transmission line protection and fault location. The CPU of most microprocessor-based protection device at present is 16 bit Single Chip Micyoco, because of its slowly processing speed, it is hard for the Single Chip Micyoco to implement the more complex protection function.so there is important practical meaning to research and develop microprocessor-based protection device of higher performance. After synthetical presentation of developmental history and current research result of microprocessor-based protection devices, the paper bring forward a new kind of microprocessor line protection device based on DSP (TMS320F2812) .the paper emphasize the analyzing of algorithm of distance protection, digital filter , power system swing block ,selectivity of faulty phases and transmission line fault location and so on.As to the algorism of microprocessor-based protection, the distance protection utilize the algorism of R-L model that combines the short data windows and long data windows. And the paper use the method of "R out of N" to increase the reliability of the protection. This method take into account both the speed and reliability. As to the algorithm of transmission line fault location, the paper adopt an accurate faulty location algorithm for transmission lines based on R-L model parameter identification and least-squares algorithm,and testify its validity and reliability.This DSP-based protection device has the characteristics of high speed and reliability. It can meet the requirements of 110 kV transmission line protection.