Design of the Halbach Hybrid-Excitation Compulsator

Pulsed alternators integrate kinetic energy storage, electromechanical energy conversion, and pulse shaping into one unit, and it is the research focused on the field of pulsed power sources. The electrical excitation and the permanent magnet excitation are contained in one hybrid-excitation pulsed generator together in which the advantages of two different excitation types are integrated. The brush slip ring mechanism with low reliability and high maintenance costs can be cancelled. In addition, the electromagnetic field can be adjusted quickly by external electrical excitation source and correspondingly the performance can be quickly adjusted. An all-iron-core hybrid-excitation compulsator prototype was designed, fabricated, and optimized. The hybrid excitation concept was validated in the research of compulsators. Although compulsator research is mainly focused on the all-air-core electrical excitation topology, there exist some bottleneck technologies that restrict the application of compulsators in actual fields. The hybrid-excitation compulsator can decrease the cost, increase the reliability, and widen the application scope of compulsators, especially in the middle-low power range. The Halbach array is a permanent magnet arrangement structure, which is a combination structure of different direction arrays. The Halbach array offers a number of attractive features in comparison with the normal array. The air-gap magnetic flux can be increased and the rotor yoke magnetic flux is decreased. Based on this, the Halbach array can be designed on the composite rotor core. A part-air-core compulsator that includes an air-core rotor and an iron-core stator was designed. For analyzing the electromagnetic design results, the 3-D model was built and finite element analysis method was used. The performance simulation results of the Halbach hybrid-excitation compulsator were presented.