Computer Modelling Of 3d Transient Thermal Field Coupled with Electromagnetic Field in One-phase Induction Motor with Locked Rotor

摘要

Purpose - This paper aims to present the plan to develop the known algorithm for thermal and electromagnetic coupled problem calculation. This is used for a one-phase induction motor with locked rotor for nominal and lowered voltage excitation values. It also aims to prepare a calculating method for the average heat transfer coefficient for natural convection from the induction motor housing external face. Design/methodology/approach - The numerical investigations proposed are based on 3D finite element models for thermal and electromagnetic fields analysis and 3D volume element model for average heat transfer coefficient calculations. The thermal model is experimentally validated. Findings - The paper provides a numerical method to calculate average heat transfer coefficient for the induction motor housing external faces. This coefficient is shown as a temperature function. Temperature variations in the various parts of the induction motor with locked rotor are calculated. The calculation results are compared with the measurement results. Research limitations/implications - The average heat transfer coefficient is calculated for a limited range of temperature and for the natural convection case. Electromagnetic field analysis does not include losses in the motor core. These losses could be included in the thermal and electromagnetic fields coupled calculation problem as an additional heat source for the thermal field. Originality/value - The paper presents a 3D transient thermal field and electromagnetic field coupled problem and proposes a method for calculating the average heat transfer coefficient of natural convection from the housing external face of the induction motor with a locked rotor.