| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve an efficiency of a scalar-controlled brushless DC motor. <P>SOLUTION: A driving device of a brushless DC motor comprises an induction voltage measuring part for measuring induction voltages of three-phase coils, and a corrected trapezoidal wave creation part for creating corrected trapezoidal waves having a period synchronized with a rotation angle of a detected rotator. A PWM control of an inverter circuit for driving a motor is executed according to comparison between the corrected trapezoidal waves and triangle waves. The corrected trapezoidal waves have an inclined rise, a flat peak and an inclined drop starting from a value of the induction voltage for a phase of the three-phase coils, in which energization is started. A voltage applied to the motor is always larger than the induction voltage of the motor, so as to always generate a torque and improve efficiency. <P>COPYRIGHT: (C)2013,JPO&INPIT |
