A 220 Kv Saturation Type Sfcl Modeling And Simulation Analysis And Its Application

In recent years, as China’s power distribution centralization and the capacity of power generator became more and more large, the contact of power gird is increasingly close, the ring network is increasing year by year and the system equivalent impedance is smaller every year, the power system’s short-circuit current level is rising year by year. Due to the limitation of the traditional fault current technology, it has been unable to meet the development needs of the modern power grid. But the superconducting fault current limiter with its unparalleled performance is studied by domestic and foreign power scholars.At present, the application of the saturation type superconducting current limiter is seldom used in the actual power system. As a new type of fault current limiting device, it can limit the large short-circuit current, but it will also bring a series of effects to the power system operating characteristics. In this paper, based on the study of a variety of limiting technology and the general magnetic saturation SFCL, a kind of220kV new saturation-type superconducting fault current limiter is proposed, and When the saturation type SFCL is applied to the transmission system, the ability of limiting the short-circuit current and the transient stability influence of one generator infinite model were analyzed.This article first elaborated the superconducting current limiter classification and the principle of work, because of the defects that the common saturation-type fault current limiter can’t show the a full-wave current-limiting characteristic, a kind of220kV new saturation-type superconducting fault current limiter that it can limit current by full wave and without separate control excitation device is proposed in this paper, its impedance characteristic and current limiting principle were analyzed by the way of mapping and its limiting factor is calculated. By using the extended equal area criterion (EEAC), based on one generator infinite model, When the saturation type SFCL is applied to the transmission system, the power system transient stability influence with different fault type, fault location and different SFCL impedance are studied.Based on the Simulink/Matlab, this paper built a new saturation-type SFCL model and mounted on one generator infinite model. At the same time, respectively, the system line first and end of the three-phase short circuit, two phase short circuit of grounding, two phase short circuit and single-phase short-circuit fault were simulated, and short circuit currents and the generator power angle curve change were analyzed with and without new saturated SFCL. The simulation results show that:the effect of SFCL in the power grid is consistent with the theoretical analysis; it not only has the very strong current limiting capacity, but also help the system transient stability.