Determination of critical thermal operation for small squirrel cage motor

The thermal design of small squirrel cage machines is a challenge in comparison with the permanent magnets machines of the same frame size. When designing the machine, the calculated temperatures in all parts should be lower than their critical temperatures. This paper aims to perform thermal analysis for different load types in order to achieve a safe thermal design of the motor. The machine under study in paper is induction motor. Basic dimensions of the stator and the frame are based on the permanent magnet motor. Thermal network method was used for thermal analysis of the machines. Practical measurements for comparison and validation of the existing results should be implemented in future. The paper offer useful practical information for a safe thermal design of induction motor. Paper demonstrates how can be new designed induction motor loads without thermal damaged. The practical significance of the paper is beneficial for the designers of induction motor (IM).