| 摘要 |
PROBLEM TO BE SOLVED: To provide a controller for a synchronous motor capable of reducing the size and the cost of a synchronous motor by preventing deterioration in torque control accuracy in an operating state with a high magnetic saturation level and also a decrease in the power factor of a motor. SOLUTION: In a vector control system in which the armature current of a synchronous motor is controlled by separating into a d-axis component and q-axis component, a magnetic flux computing element 8 is provided for calculating d-axis component and q-axis component of the magnetic flux of the armature current as well as d-axis component and q-axis component of the magnetic flux of a motor from the field current; and this magnetic flux computing element 8 is equipped with at least one of the computing elements such as a computing element for correcting a computed value of a q-axis component of a magnetic flux of motor based on the d-axis component of armature current, a computing element for correcting d-axis component of the magnetic flux of motor based on q-axis component of armature current, and a computing element for correcting q-axis component of magnetic flux of a motor based on field current. Even though the magnetic saturation level becomes high, there is no lowering in computing accuracy of the magnetic flux of a motor, so that the accuracy of vector control can be improved and the density of magnetic flux of a synchronous motor can be made higher in design, so that compactness and cost reduction can be achieved. |
