Study on the self-excitation condition of a two-phase air-core pulsed alternator

As a new type of pulsed power supply, air-core pulsed alternators concentrate all the functions of energy storage, energy conversion and power conditioning in one machine. It is also easy to condition the output voltage and current waveforms. These advantages make it a promising compact power supply system for a variety of fields including laser and electromagnetic launchers. The whole work process of a two-phase air-core pulsed alternator can be divided into self-excitation process, discharge process and energy reclaim process. The aim of the self-excitation is to generate an adequate current in the exciting winding for the discharge process and there is a condition to realize a successful self-excitation for a two-phase air-core pulsed alternator. In this paper, the relationship between the successful self-excitation condition and the design parameters of the air-core pulsed alternator was established. A comparison of the successful self-excitation condition between a single-phase air-core pulsed alternator and a two-phase alternator was also made. To verify the conclusions of the paper, some simulations were performed on a single-phase air-core pulsed alternator and a two-phase air-core pulsed alternator. Each phase armature winding of the two-phase alternator shares the same electrical parameters as the single-phase alternator. The results and conclusions of the analyses and simulations in this paper can offer guidance for the flexible design and optimization of two-phase air-core pulsed alternators.