| 摘要 |
PROBLEM TO BE SOLVED: To increase reliability by reducing the noise and restricting heating of a switching element. SOLUTION: In a control means 8 for controlling operation by supplying three-phase electric power to the three-phase winding 2 of a motor 1 through an inverter 3, when the rotational direction of the motor 1 is inverted, the current supply from the inverter 3 is stopped temporarily, and the initial value of a continuity ratio of movement in the opposite direction is set at a prescribed value. Each time an interrupt signal from an interrupt signal generator 19 which is inputted in synchronism with the rotation of the motor 1 is inputted, the continuity ratio is set higher value sequentially, and finally the continuity ratio is set so as to reach a speed command value which an operating part 18 commands. The continuity ratio corresponding to a speed error between the speed command value and real speed is not set at the time of inversion, so that no heavy-current flows, and it is possible to eliminate hard stops and hard startups, reduce noise, to prevent the generation of mechanical overloads, and suppress heating of switching elements 6u-7w. |
