Research On The New Principle Of Single-Phase Adaptive Reclosure

Single-Phase Adaptive Reclosure technique can quickly identify the fault type after fault occurs. If the fault is transient, it will reclosure, while in the situation of permanent fault, it will be locked. So, it overcomes the disadvantage of the traditional automatic reclosing which would reclose when permanent fault occurs. Thus, the damage comes from secondary fault is avoided. So the Single-Phase Adaptive Reclosure technique aroused the interest of both domestic and foreign researchers. This paper systematically analyzes the existing research results and their drawbacks both in domestic and foreign countries. Then a new method to identify the fault type is proposed which can be used on the EHV/UHV transmission lines with shunt reactors. Firstly, the paper analyzes the arc features when transient fault occurs, then the models are introduced including its mathematical model and ATP/EMTP model. Secondly, for the transmission lines with shunt reactors, we research how the neutral reactor affects the single-phase adaptive reclosure system, and the optimal value of neutral reactor is given after a series of derivation. Finally, by analyzing the characteristic of the fault phase shunt reactor current under different type of faults, a new method for single-phase adaptive reclosure is proposed which is on the basis of different trend of the decaying component in the current. A large number of ATP/EMTP simulation results show that the theory and the method is correct and effective...