Verfahren zur Messung charakteristischer Konstanten für Wechselstrommotoren und auf diesem Verfahren basierender Regler

摘要

An inverter (4) corrects an output voltage by the magnitude of output voltage error due to a dead time and an ON-state voltage drop in power elements to energize an AC motor (5) in a manner of single phase alternating current excitation, calculating an active component of current Iq and a reactive component of current Id from the phase theta of an excitation voltage vector and a detected instantaneous current value iu, measuring characteristic constants of the motor, a combined resistance ( r1 + r2 ) and a combined leakage inductance ( l1 + l2 ) from an excitation voltage command value Vc1, Id and Iq. The measured values are used as the control constants for a speed sensorless vector control (7). Further, the resistances r1, r2, and a self-inductance L1 which are control constants can be obtained based on the component in a primary voltage vector direction of a primary current vector Iq' and the component pi /2 delayed from the primary voltage vector direction of the primary current vector Id'. According to the present invention, the characteristic constants can accurately be measured without any inverter output voltage sensor.