STATOR FLUX ESTIMATION DEVICE OF INDUCTION MOTORS AND METHOD THEREFOR

摘要

PURPOSE: An apparatus and a method for estimating stator flux of an inductive motor are provided to enhance the reliability of the estimation of the stator flux by correcting a flux estimation error due to a variation of parameters and a variation of stator resistors, and a voltage error. CONSTITUTION: An apparatus for estimating flux of a state of an inductive motor includes an auxiliary current production portion(101), a calculator, a corrective term production portion(103), a flux compensation portion(104), and a flux production portion(109). The auxiliary current production portion(101) produces the auxiliary current from the d-axis current, the q-axis current, and the estimated flux of the inductive motor. The calculator is used for calculating a current error from the auxiliary current and the d-axis current. The corrective term production portion(103) produces an intensity correction term and an angle correction term of the stator flux on the basis of the d-axis current, each frequency of the stator flux, and the current error. The flux compensation portion(104) corrects the stator flux on the basis of the intensity correction term and the angle correction term. The flux production portion(109) estimates the stator flux on the basis of the voltage and the current applied to the inductive motor and the corrected stator flux.