| 摘要 |
PROBLEM TO BE SOLVED: To provide a control device for a drive system having operation efficiency improved by making DC output voltage supplied from a converter device to an inverter device be variable depending on rotation speed of an electric motor driven by output of the inverter device.SOLUTION: A control device for a drive system in which a converter device 14 converts AC power to DC power having variable voltage, an inverter device 15 inversely converts the DC power to AC power having variable voltage and a variable frequency, and an electric motor 13 is driven by the output of the inverter device 15 comprises: a variable voltage command device 44 for outputting a DC voltage command value for generating DC output voltage of the converter device 14 depending on rotation speed of the electric motor 13; and an efficiency comparison circuit 43 which compares a present efficiency calculation value calculated by a system whole efficiency calculation circuit 42 with the previous efficiency calculation value, and gives a correction command value to a DC voltage command value for the converter device 14 according to the comparison result so that system whole efficiency is maximum. |
