A neodymium hybrid fault current limiter

Summary This paper presents a new hybrid type fault current limiter topology for use in distribution systems. The proposed system includes a fast mechanical contact switch, a semiconductor switch, a neodymium magnetic core, and a metal-oxide varistor. A custom control algorithm is developed to detect the fault occurrence and perform the correct switching order of the proposed hybrid fault current limiter. A novel feature included in the proposed hybrid fault current limiter is the ability to control the fault current magnitude through the use of pulse-width modulation. In addition, the Jiles-Atherton method of hysteresis is used to model the nonlinear permeability of the NdFeB core. Simulations are performed using Power System Computer Aided Design (PSCAD) for both a high voltage and a low voltage system. A low voltage (20 V, 1.25 A) hardware system is built to verify the PSCAD simulations, and the results are presented. In conclusion, a comparison between the PSCAD simulations and the hardware experimental results verify the correct modeling of the proposed topology and confirm its feasibility.