| 摘要 |
PURPOSE: To reduce the capacity on the regeneration side of a DC voltage supply device by performing compensation so that an acceleration/deceleration rate can be reduced for preventing the output voltage of the DC voltage supply device from exceeding a voltage detection level. CONSTITUTION: When a DC bus voltage detected by a DC detection circuit 5 of a DC voltage supply device 1 increases over an overvoltage detection level due to the regeneration operation of each AC variable speed drive device 2, a specific reduction rate is calculated by an acceleration/deceleration rate low reduction rate operation circuit 6 and each AC variable drive device 2 at a lower level changes an acceleration/deceleration rate on the value. When the acceleration/deceleration rate decreases, the amount of regeneration decreases and a DC bus voltage decreases, thus reducing also the acceleration/ deceleration rate reduction rate for optimum operation within a range where no capacity on the regeneration side is exceeded. A small regeneration capacity can be effectively used by determining whether the acceleration/deceleration rate reduction rate can be outputted to each AC variable speed drive device 2 or not by a selection circuit 8. |
