| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a device for driving a brushless DC motor, by which stability in driving with high load and high speed of the brushless DC motor is enhanced, a driving range is expanded, and an unstable state caused by an external factor is suppressed. <P>SOLUTION: In the device for driving the brushless DC motor including a brushless DC motor 4 composed of a rotor having a permanent magnet and a stator having a three-phase winding, and an inverter 3 for supplying electric power to the three-phase winding, a rectangular wave having a conduction angle of 120 degrees or more and 150 degrees or less, or an equivalent waveform is output at low speed, then a rectangular wave and sine wave each having the conduction angle of 120 degrees or more and less than 180 degrees, or an equivalent waveform is output at high speed, in a predetermined frequency with a prescribed phase relation to a phase current of the brushless DC motor 4, and an induced voltage, the phase current and a terminal voltage phase of the brushless DC motor 4 are stabilized with an appropriate phase relation according to load and speed, thereby enhancing driving stability with high load and high speed. <P>COPYRIGHT: (C)2010,JPO&INPIT |
