Sensorless monitoring of induction motor temperature with an online estimation of stator and rotor resistances taking the effect of machine parameters variation into account

A novel and accurate method for induction motor online temperature monitoring based stator and rotor resistances thermal variation using Arduino-Matlab Simulink technique is proposed and implemented in this paper. Estimation of stator resistance as an indicator of stator winding and rotor bars temperature. Obtaining an accurate determination of stator and rotor resistances is very important for this approach. A new determination of stator and rotor resistances for purpose of motor temperature monitoring in steady-state operation is proposed based on the motor dynamic model in a rotating reference frame. In this model, the effect of iron core losses is taken as a reflection of iron core resistance as a voltage drop in the stator and rotor circuits. The skin and skew effect in the rotor circuit, stray load loss in stator and rotor circuits, variation effect in the magnetizing inductance, variation in stator and rotor resistances are taken in this model to obtain an accurate temperature on line monitoring. An experimental result on the line connected induction motor satisfied the validity of the proposed model of analysis and method of motor temperature monitoring