Analysis And Research Of Claw-Pole Alternators For Automotive Applications

A conventional claw-pole alternator and a novel hybrid excitation claw-pole alternator for automotive applications are studied in the paper. The shape of the claws leads to a truly three dimensional (3D) magnetic field in all regions. Consequently, for the correct calculation of magnetic field and alternator characteristics, a 3D numerical method is required. On the basis of 3D magnetic field computation, the characteristics of the alternators can be achieved. There is lack of the research on the alternators.Compared with the conventional alternators, a hybrid excitation alternator with additional permanent magnets can improve the low-speed performance, output performance and the efficiency. Besides, it has adjustable magnetic field. Therefore, it is of great importance to analyze and study the hybrid excitation alternators.The 3D magnetic field computation and parameters computation of both the conventional claw-pole alternator and the novel hybrid excitation claw-pole alternator are done in the paper. It can be discussed as follows.The conventional claw-pole alternator is analyzed and modeled using a 3D finite element (FE) method. The 3D magnetic field in the alternator is obtained. The leakage flux of the conventional claw-pole alternator is computed in terms of different parameters. On this basis, the leakage flux of the hybrid excitation claw-pole alternator is computed in terms of different parameters.In addition, the inductances of the windings of the conventional claw-pole alternator are achieved. The load performance of the conventional claw-pole alternator is computed by an iteration method. The calculated results are validated by the experimental results.The hybrid excitation claw-pole alternator is analyzed and modeled using a 3D finite element method. The 3D magnetic field in the alternator is obtained. In addition, the inductances of the windings are achieved. The 3D magnetic equivalent circuit (MEC) model of the hybrid excitation claw-pole alternator is presented. On this basis, the load performance and the efficiency of the alternator are computed. The output current of the hybrid excitation claw-pole alternator is optimized in terms of different parameters of permanent magnets. The optimization results are given.The sample of the hybrid excitation claw-pole alternator is presented. The hybrid excitation claw-pole alternators in mass production have a good performance and work well.The conventional control system of the claw alternator has a low efficiency, so it is necessary to improve it. The hybrid excitation claw-pole alternator control system based on fuzzy-PI controller is established and discussed. Finally, the present automotive electrical systems and the future automotive electrical systems are discussed.