| 摘要 |
PROBLEM TO BE SOLVED: To speed-control an electric motor over a wide range by controlling the intermittent operation of a switching element in a boosting chopper circuit and controlling the modulation of pulse width, so that deviation speed between command speed and detection speed with respect to the electric motor becomes zero. SOLUTION: An AC power source 1 is converted into DC voltage Ed via a rectifier circuit 2 and a boosting chopper circuit 3. It supplies a DC voltage to an inverter 4, and the inverter 4 drives a synchronous motor 5. At this time, the switching element of the boosting chopper circuit 3 is operated intermittently with the deviation speed of command speed and detection speed with respect to the synchronous motor 5 executed by a microcomputer 6. The microcomputer 6 controls the modulation of pulse width so that the deviation speed of command speed and detection speed against the synchronous motor 5 becomes zero, in the low speed region which is not more than a prescribed value in the synchronous motor 5. |
