Analysis of the Electromagnetic Parameters of an Induction Motor with Ring Windings with Ceramic Insulation

The induction motor with ring windings (IMRW) was developed by Electrical Engineering Department of Ural Federal University for the processing of nuclear waste. Due to the ceramic insulation of the stator windings, the motor can operate in conditions of increased radiation and temperature for 2-3 years. In hard conditions traditional three-phase induction motors are designed with organic insulation for stator windings, and they have a service life about 2-5 months only. After 2-5 months they must be replaced because of the destruction of the stator windings insulation. Extending the lifetime of a nuclear waste engine is an important goal as IMRW will save human resources involved in replacing machines in high radiation conditions.The first IMRW prototype’s power is P=2.2 kW, the number of poles is 2p = 6; it was designed on the basis of the general industrial induction motor with squirrel cage of the AO2 series. IMRW has the same dimensions as the motor AO2-32-6. However, previous studies have shown that IMRW design has a number of disadvantages and the engine has to be improved, in particular, it is necessary to take into account the leakage flux in the stator, because it affects the magnitudes of the starting and maximum torque.In IMRW the leakage flux can be reduced by changing the number of pole pairs of IMRW or increasing the height of the motor rotation axis. The first method leads to the need to use a frequency converter; the second method involves increasing the diameter of the engine and decreasing its active length.