Influence of Driving Mode on Loss Characteristics of Doubly Salient Brushless Motor With Rectangular Wire Armature Winding

The loss of a doubly salient brushless motor (DSBLM) with rectangular wire armature winding mainly includes ac copper loss, iron loss, and converter loss. The driving mode has a certain influence on motor loss. Therefore, the loss characteristics of a DSBLM with rectangular wire armature winding driven by brushless dc (BLDC) and brushless ac (BLAC) are comparatively studied in this article. First, the magnetic flux density waveforms of armature winding and stator under ideal currents drive are compared, and the waveform changes of ac copper loss and iron loss are analyzed. Second, the effect of pulsewidth modulation (PWM) on motor loss for actual operation in two driving modes is studied. Third, the converter loss of different driving modes is also considered. Finally, the theoretical analysis and simulation results are verified by the experimental results of a DSBLM. In the BLAC driving mode, a DSBLM with rectangular wire armature winding has better loss characteristics.