3D-FEA based-comparison of different topologies of claw-pole alternators with a dual excitation

The paper deals with a 3D-FEA based comparison of four topologies of claw-pole alternators equipped with a dual excitation, namely: (i) the series-hybrid excited claw-pole alternator (SHECPA), (ii) the parallel-hybrid excited claw-pole alternator (PHECPA), (iii) the hybrid excited brushless claw-pole alternator (HEBCPA), and (iv) the PM-assisted hybrid excited brushless claw-pole alternator (PMA-HEBCPA). The study is initiated by a description of their topologies and an analysis of their rotor-stator flux linkages. Then, a special attention is paid to their back-EMF production capabilities, with emphasis on the no-load characteristics and the back-EMF wave-forms and harmonic contents. In order to highlight the possible improvements introduced by the dual excitation, the comparison is extended to the case of the conventional CPA which is taken as a reference.