A new thermal observer for squirrel-cage induction motor

In the present paper the authors built a device for the temperature measurement in the stationary as well as rotating parts of electric machines. The effectiveness of the device is tested in real working condition on squirrel cage induction machine. The unique construction of the device for continuous rotor temperature monitoring is briefly described. This device is a part of a complete acquisition system which is used for precise testing and investigating of a thermal process. A new thermal observer based on direct stator temperature measurement under normal running condition with no additional sensors is proposed.