Fault current limiting transformer with variable reactance

The objective of this work is to prove experimentally the ability of a transformer with variable reactance to limit the fault current and to adjust the secondary voltage. This transformer is able to change its leakage reactance by a shift of a movable iron-core block. It has three functions of voltage transformation, fault current limitation, and voltage regulation. A small trial apparatus was manufactured and these functions were demonstrated experimentally. Its characteristics and some points that should be improved are also clarified.