METHOD FOR CORRECTING ESTIMATE OF SPEED OF INDUCTION MOTOR AND ITS DEVICE

摘要

A magnetic estimator (7) of a controller used for sensor-less vector control of an induction motor calculates a speed estimate omega rest and a phase estimate theta lest from inputted alpha - and beta -phase voltage commands V alpha <*>,V beta <*> and inputted alpha - and beta phase currents is alpha , Is beta and outputs them. A speed corrector (8) receives the information and calculates the difference between the derivative of the phase estimator and a separately inputted slip angular velocity to make the difference a deviation omega 'rest. The speed estimate omega rest is corrected by a correction value which is the product of a correction gain and a primary delay integral of the remainder of the subtraction of the slip angular frequency omega s from the deviation to determine an accurate speed estimate omega ''rest.