TEMPERATURE ESTIMATION DEVICE, TEMPERATURE ESTIMATION METHOD, AND CONTROLLER

摘要

PROBLEM TO BE SOLVED: To accurately estimate the temperature of a coil when a motor is operated.SOLUTION: A temperature estimation device includes: detection means (a current sensor 22) for detecting the value of current flowing through a motor 20; correction means (a current correction function arithmetic unit 34) for correcting the current value detected by the detection means on the basis of the rotation speed of the motor; and estimation means (a sequential least square method arithmetic unit 35) for calculating the resistance value of the coil of the motor by a sequential least square method on the basis of the current value corrected by the correction means and a voltage command value specifying voltage applied to the motor and for estimating the temperature of the coil from the resistance value. The correction means is characterized in that it corrects current by a two-variable polynomial equation using the current flowing through the motor and the rotation speed as variables and the two-variable polynomial equation includes a constant term corresponding to a dead time a driving system of the motor has.