Optimal Design and analysis of an electromagnetic fault current limiter based on rotating variable reactor

In this paper, a new electromagnetic fault current limiter with rotary motion is presented. The features of this limiter are its simple structure, low construction and maintenance cost, optimal performance speed, and easy and quick return to initial conditions after the error is corrected. This limiter consists of two spherical air core coils with the ability to rotate freely around the radial axis. In normal conditions, due to the presence of negative mutual inductance between two coils, the total inductance of the limiter has the lowest value. When a fault occurs due to the forces created between two coils, these coils are automatically rotated relative to each other, and the limiting inductance increases rapidly, and the fault current is limited. In this article, for the optimal design of the limiter, the effect of all the limiting parameters such as radius, height, thickness, number of turns and the initial angle of the coils has been investigated and in order to achieve the highest final inductance and the highest operating speed, a suitable value is determined. The results of the simulation show that the designed limiter has a better performance than the initial design and has a good performance speed and final inductance.