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A saturated iron core superconducting fault current limiter (SISFCL) has an important role to play in the present-day power system, providing effective protection against electrical faults and thus ensuring an uninterrupted supply of electricity to the consumers. Previous mathematical models developed to describe the SISFCL use a simple flux density-magnetic field intensity curve representing the ferromagnetic core. As the magnetic state of the core affects the efficient working of the device, this paper aims to present a novel approach in the mathematical modeling of the device with the inclusion of hysteresis.

The Jiles–Atherton’s hysteresis model is utilized to develop the mathematical model of the limiter. The model is numerically solved using MATLAB. To support the validity of model, finite element model (FEM) with similar specifications was simulated.

Response of the limiter based on the developed mathematical model is in close agreement with the FEM simulations. To illustrate the effect of the hysteresis, the responses are compared by using three different hysteresis characteristics. Harmonic analysis is performed and comparison is carried out utilizing fast Fourier transform and continuous wavelet transform. It is observed that the core with narrower hysteresis characteristic not only produces a better current suppression but also creates a higher voltage drop across the DC source. It also injects more harmonics in the system under fault condition.

Inclusion of hysteresis in the mathematical model presents a more realistic approach in the transient analysis of the device. The paper provides an essential insight into the effect of the core hysteresis characteristic on the device performance.

From the point of view concerned with the development of the information, oriented functions in social activities, recently power consumption has rapidly increased. On the other hand, ability of power supply has not been increased to follow this increasing consumption, because it is difficult to construct new power generation plants. Therefore, reserve capacity of power supply is going to be decreased and power down has become a serious problem. To prevent the serious power down and to maintain a stable power supply, we had already proposed a passive fault current limiter using a permanent magnet with high coercive force, high remanent magnetic flux density and a ferrite core with high permeability, low saturated flux density compared to that of a permanent magnet. In this paper, the flux distribution of the limiter is investigated using the three dimensional finite element method.