On the Thermographic Analysis and Thermal Re-sistance Estimation of the Capacitor-Run Single-Phase Induction Motors

Abstract

The real-time estimations of heating of the elec-tromechanical converters are important for both overheat-ing prevention and overall efficiency optimization during operation. The two-phased induction motors with capacitor-run capacitors onto the auxiliary phase are sensitive to the capacitance variations of the capacitor. In this respect, the optimization of the two-phased induction motors with elec-tronically-switched, capacitor-run, supplied from frequency inverters may be achieved if the elliptical magnetic motion field into the machine is controlled such as the ratio between the maximum and the minimum of its amplitude is reduced to unity. Observations of the heat of the machine’s body and an appropriate thermal model may provide information about the eccentricity of the magnetic motion field in the machine. In this work, the authors investigated the impact of the capacitor-run capacitance onto the characteristics of the thermal field of the machine. In this perspective, the authors implemented a method based on the image analysis techniques that allows estimating: (a) the geometric features of the machine from the boundaries of the thermal field, and (b) the temperature distribution onto the cross-section of the body in correlation with the main components of the ma-chine and (c) the thermal resistance of the machine’s body. images