Research On Constitution Scheme And Algorithm Of Regional Protection

With the development and the expansion of smart grid, the grid structure and operation have become increasing complex. Traditonal relay protection setting and coordination based on local information can not clear fault rapidly and accurately. This paper studies the regional protection scheme according to introduction of multi-sourcer information, and proposes one regional protection algorithm based on distance protection fitting factor and the other one algorithm based on adaptive current protection suiting factor, and studies the regional protection engineering realization combined with the practical engineering.This paper proposes a regional protection algorithm based on distance protection fitting factor. First of all, it defines contribution degree of distance protection action to fault line recognition as the distance protection contribution degree. Thus, fitness protection function and expected fitness protection function can be built by applied it as weight. Then, according to the distance protection fitting factor, the ratio of fitness protection function and expected fitness protection function, the fault line can be identified. The method is not affected by the information non-synchronous. Meanwhile, it conquered the problem of the uncertainty brought by traditional weight dependent on imperfect experience. In addition, it has smaller amount of calculation, high fault tolerance, therefore, can provide higher practicability.Another regional algorithm is proposed which is based on adaptive current protection suiting factor. With adaptive current protection as basic principle, the algorithm has more reliable information source, and can adaptive the system operation mode and fault type changes. The contribution degree of adaptive current action to fault line recognition is used to be the weight of suitability protection function and expected suitability protection function. According to the adaptive current protection suiting factor, the ratio of suitability protection function and expected suitability protection function, the fault line can be identified. Under the situation of asynchronous communication system, or lacking or having a large number of inaccuracy adaptive current protection action information, it can still estimate the fault line.In the linux environment it is formed the modularization program of regional protection algorithm, which is composed of four components. The four components are boot modult by fault identification, and regional protection algorithm based on integrated distance protection, distance protection fitting factor and adaptive current protection suiting factor. The modularization program in the linux system output protection operation instructions to the actual device, forming the regional protection actual device. Finally using the model on the platform of RTDS(Real Time Digital Simulator) based on DouYun grid the of protection device is checked.