I. Introduction
The feeding of rail launchers requires the availability of generators which able to supply extremely intense currents, often of impulsive waveform. The air-core pulsed alternator seems to be one of the most promising technologies in the field of electromagnetic launchers power supplies [1]–[4]. These systems are made of nonferromagnetic materials (usually with a very high specific strength), and in comparison with the iron-core generators, they need a very high current to produce the proper exciting field [5]. On the contrary, due to the low values of inductances, the peak value of the output pulsed current can be increased. Compared to the iron-core generators, the maximum speed of an air-core rotor can reach higher values, increasing the energy storage ratio. Although self-excitation mode is usually adopted in these systems, some different excitation strategies were proposed to increase their performances [6], [7].