Patent ID: 8742705
Filing Date: 2014-06-03
Classification: H02P

Abstract:
1. An apparatus for operating interior permanent magnet synchronous motor (IPMSM) by receiving a first current command of a flux weakening control region I in a system including a detector measuring a position and a speed of a rotor of the IPMSM, the apparatus comprising: a feedback unit transmitting over-modulated voltage information to a correction unit; the correction unit using the rotor speed and the over-modulated voltage information to correct the first current command to a second current command of a flux weakening control region II; a control unit controlling the second current command to output a voltage; a first limit unit limiting an output of the control unit to a maximum voltage synthesizable by an inverter unit; and the inverter unit applying a 3-phase voltage command for following a command torque to the IPMSM using an output of a voltage limit unit; wherein the correction unit comprises a processing unit correcting the first current command to generate the second current command in case of flux weakening control region II, and a second limit unit limiting a size of current from the second current command; wherein the processing unit comprises a decision unit determining the flux weakening control region II, a determination unit determining a direction of correction of current command, a calculation unit calculating a proportional gain using a current rotor speed and a maximum rotor speed, a third limit unit limiting a size of the current change, a section defining unit defining a hysteresis section for defining the flux weakening control region I and the flux weakening control region II, and an adding unit outputting the second current command by adding a reference current to an output of the section defining unit.