| 摘要 |
PURPOSE:To accurately decide the firing time point of an inverter by counting the pulse from a pulse generator mounted on a motor shaft, and digitally comparing the counted content with a firing phase angle command signal to decide the commutation. CONSTITUTION:A pulse generated from a pulse generator (PG)9 is input to a direction discriminator 10 upon rotating of a motor 2, the rotating direction of the motor 2 is discriminated to instruct a ring counter 6 to clockwise or counterclockwise. On the other hand, a counter 4 counts a pulse from the PG9, outputs the counted result to a comparator 5, the comparator 5 resets the counter 4 when the counted results coincides with the command signal of a firing phase angle, and restarts the counter. The output of the comparator 4 is added to a ring counter 6, the output of the counter 6 is decoded by a decoder 7, and applied through a pulse amplifier 8 to the inverter 1 as a thyristor firing pulse. |
