| 摘要 |
PROBLEM TO BE SOLVED: To provide an inverter apparatus for motor drive that simply controls starting voltage and frequency, can miniaturize an inverter as compared with the motor that is supported by a friction type bearing, and at the same time does not require the need for increasing the support force of a magnetic bearing in starting as compared with the normal case. SOLUTION: The inverter apparatus 1 for motor drive comprises a rectifying circuit 1, a voltage variable circuit 2, a DC-AC conversion circuit 3, a control circuit 4, a frequency control circuit 5, starting voltage setting equipment 6, starting frequency setting equipment 7, and storages 11 and 12, controls the voltage variable circuit 2 and DC-AC conversion circuit 3 by the control circuit 4, and outputs power having a specific voltage and frequency to a motor M where the rotor is supported by a magnetic bearing. Also, in the inverter apparatus 10 for motor drive, a current detection circuit 9 is provided, and the control circuit 4 has a function for comparing an actual starting current value detected by the current detection circuit 9 with a preset setting starting current value, and determining an optimum starting voltage value or starting frequency value according to the comparison result. |
