Patent ID: 7750595

Claim:
A rotating machinery controller for controlling a rotation-related physical quantity of a rotating machinery by operating switching devices of an inverter to supply electric power to the rotating machinery, the rotating machinery controller comprising: rectangular wave control means for controlling an output torque of the rotating machinery toward a desired torque by operating the switching devices such that an on-state and an off-state occur one time for one cycle period in electrical angle of the rotating machinery; instantaneous current value control means for, in order to control an actual current of the rotating machinery within a predetermined hysteresis region which is determined by a command current to the rotating machinery, operating the switching devices on the basis of a magnitude relation between upper and lower limits of the hysteresis region and the actual current; and switching means for, when a current flowing through the rotating machinery deviates from the hysteresis region while the control by the rectangular wave control means is undertaken, switching the control by the rectangular wave control means to the control by the instantaneous current value control means.