Abstract
We have studied the possibility of utilizing inversely connected pancake coils in series for fault current limiters. Fundamentally, pancake coils have various merits, including 1) a high winding packing factor, 2) high mechanical strength, 3) good electric insulation characteristics, 4) good current balance between the coils, and 5) high impedance. Therefore, the authors introduced an inversely connected pancake coil system. In this paper, the impedance characteristics of inversely connected pancake coils are studied. The change in coil resistance between normal operating conditions and under fault conditions is shown, and the leakage inductance of the coils was measured. The results are compared to calculations obtained using FEM.
