Enhanced Power Multi Excitation Brushless DC Generator Using Parallel Magnetic Circuits

This paper proposes a multi-excitation brushless generator (MEG) using parallel magnetic circuits for DC power system with enhanced output power capability. The multi-excitation sources include the permanent magnets, DC excitation, and AC excitation. The key is that an appropriate AC excitation field is constructed and combined with the PM and DC excitation fields, thus realizing field enhancement, armature reaction compensation, and output power improvement. Additionally, the AC excitation power is extracted from the permanent magnet field of the MEG by utilizing the decoupled parallel magnetic circuits, realizing self AC excitation. The DC excitation winding and the diode rectifier are retained, ensuring good generator system reliability. In this paper, the operation mechanism of the proposed multi-excitation scheme is deduced and revealed. To evaluate the power enhancement of the proposed method, the MEG is compared with an existing dual-excitation generator. At last, experiment results verify the proposed method.