SENSORLESS VECTOR CONTROL DEVICE AND SENSORLESS VECTOR CONTROL METHOD

摘要

To provide a sensorless vector control device capable of rapidly reaching an efficient operating state at starting.SOLUTION: A sensorless vector control device has an open loop control and a closed loop control controlling an estimated angular rate to follow an angular rate command value, a current command value calculating portion 514 calculating a d-axis current command value based on a q-axis current value, and calculating a q-axis current command value based on the angular rate command value and the estimated angular rate, and an operation control switchover portion 519 controlling so as to output the estimated angular rate of a rotator of a brushless motor to the current command value calculating portion. The operation control switchover portion determines, when detecting that the brushless motor reaches a predetermined rotation frequency, whether or not a phase difference corresponding to a deviation of a d-coordinate system and a q-coordinate system maintains a plus area or a minus area for a predetermined time period, and when determining that it maintains, switches to a closed loop control by switching so as to output the estimated angular rate to the current command value calculating portion.SELECTED DRAWING: Figure 2