Patent ID: 11233474

Abstract:
A rotating machine drive system includes: a rotating machine that includes a plurality of windings; a phase current detecting circuit that detects a phase current to be supplied to the rotating machine; an inverter device that includes an inverter circuit that converts DC power from a DC power supply into AC power, and a control device that controls power conversion being performed by an inverter main circuit on the basis of the phase current detected by the phase current detecting circuit, the inverter device operating the rotating machine at a variable speed; and a winding switching device that switches connections of the plurality of windings in accordance with a command from the control device. In a case where the rotation zone of the rotating machine is to be changed, the control device stops the current supply from the inverter circuit to the rotating machine, and switches the rotation zone of the rotating machine from a low-speed rotation zone to a high-speed rotation zone, or from the high-speed rotation zone to the low-speed rotation zone, on condition that a line internal voltage induced by a field magnetic flux of the rotating machine is lower than the DC voltage of the DC power supply.