Design and Simulation of a Novel Brushless Doubly Fed Alternator for the Pulse Capacitor Charge Power Supply

This paper presents a novel brushless doubly fed alternator (BDFA) based on the differential mode and conducts research on its applications in a pulse capacitor charge power supply (CCPS). Since there are no brushes, the brushless doubly-fed alternator is expected to have high reliability and long service life. The excitation winding of the BDFA that is placed in the stator slots can be supplied with either dc or ac. In previous studies, regardless of the rotor configuration, the natural speed of BDFA is 60 f/(p₁ + p₂), i.e., based on the additive mode. To increase the alternator´s natural speed, expand the alternator´s operation as well as control range and to promote the alternator´s power density, this paper presents the differential mode, i.e., natural speed is equal to 60 f/ρ₁ - ρ₂|. The author will introduce the detailed design method of the BDFA based on the differential mode. Utilizing the finite-element model of the alternator, we will analyze the magnetic field distribution and calculate inductance parameters of the BDFA. Subsequently, the inductance mathematic model of the BDFA will be established. We also establish the simulation model of the pulse CCPS. Finally, we will verify the feasibility of the design scheme for the BDFA through the simulation results in a pulse CCPS system.