The field excitation adjustment characteristic of the parallel magnetic circuit hybrid excitation machine

The hybrid excitation machine (HEM) has two kinds of excitation sources, one is the permanent magnet and the other is the field current. The mathematic model of the HEM based on DQ frame is presented in this paper. Different from the conventional Permanent Magnet Synchronous Motors (PMSM), the d-axis armature current and the dc excitation current can be both used to perform the field-weakening operation, the optimal control strategy of the dc excitation current and the stator current are analyzed. The novel field weakening method and its incidental excellent performance will be shown in this paper.