| 摘要 |
PROBLEM TO BE SOLVED: To provide a driving device and a driving method for a sensorless brushless motor, with which it is possible to reduce the number of drive revolutions of the sensorless brushless motor.SOLUTION: A driving device (1) for a sensorless brushless motor according to the present invention includes a control device (7) and a power conversion device (4). The control device (7) includes: a zero-cross point detection unit (71) for sequentially detecting a zero-cross point of each phase of three phases; and a voltage setting unit (75) for increasingly setting a voltage command value of a voltage, which is applied to an armature winding in an energization phase in a first prescribed period (period TQ1) immediately preceding the zero-cross point detection by the zero-cross point detection unit (71), at a first application voltage at which the zero-cross point detection by the zero-cross point detection unit (71) is possible. The power conversion device (4) applies the first application voltage to the armature winding in the energization phase in the first prescribed period (period TQ1), thereby increasing the instant number of revolutions of a brushless motor (2) in the first prescribed period (period TQ1). |
