Vector control unit null of the electric motor which becomes making use of the speed presumption manner and the device and that speed presumption manner of the inverter Drive

摘要

PURPOSE:To enhance a response speed 4 estimating and controlling speed. CONSTITUTION:An output frequency command value Vq* is input, and a value Vq' corresponding to a q-shaft voltage command value Vq* is obtained by a q-shaft voltage command calculator 12a. The detected value Iq of a q-shaft current component is input, and a leakage impedance voltage drop due to the q-shaft current of an induction motor is obtained by a voltage drop calculator 12b. The difference between the voltage drop and Vq' by a subtracter 12c is obtained as a speed electromotive force estimated value E'. The value E' is converted into a speed estimated value omega' by a speed converter 12d. Thus, since a speed control system is separated from a current control system to estimate the speed of a motor, the response speed of speed estimation can be arbitrarily enhanced, and since response speeds of the speed control system and the current control system can be set separately from the speed estimation, the speed control of high response speed can be realized.