Unidirectional energized high efficient BLDC motor and the motor system

In a small motor system, unidirectional energized BLDC motor, can be adopted. Minato motor is one of the unidirectional energized BLDC motors. However, recently, bidirectional energized BLDC motor is being mainly studied. Controlling the direction of the torque by each armature winding for the unidirectional energized motor system is very simple. Considering the above fact, the authors developed a high efficient BLDC motor, in which unidirectional current flows. Asymmetric H-bridge circuit is used as a driver circuit for the proposed motor. This circuit is hard to break down, compared to the inverter used in the bidirectional energized BLDC motor. During high speed rotation, undesirable armature current which has deceleration action is generated. This current lowers the efficiency of the motor. In this paper, the authors propose measures for the solution in the proposed motor. The authors also show the equation of the copper loss ratio for Minato motor and the proposed motor. The “3^rd motor” which has the highest efficiency has been discovered during examination of the equations.