| 摘要 |
PURPOSE:To prevent the generation of a short-circuiting current by simultaneously turning ON two switching elements. CONSTITUTION:The controller for an AC motor comprises voltage control means of A connected in series between a single-phase AC power source 1 and a motor 3 to be controlled, voltage control means of B connected in parallel with the motor 3, and a voltage absorber having a capacitor 9 and a resistor 8 connected in parallel with the motor 3, and sets a period in which two sets of the voltage control means are simultaneously turned OFF for a short time at the time of switching to drive the two sets of the control means. Thus, two switching elements are simultaneously turned ON according to a dead time period to prevent the flow of a short-circuiting current, and the induced current generated during the period can be temporarily adsorbed by the absorber. |
