The thermal method in the diagnostic and protection system of an electric motor

Induction motors (IMs) are the most widespread electrical consumers in port and ship electrical complexes. The share of IMs among all electrical receivers operating at voltages up to 1000 V reaches up to 70% of the total number.The main factor that shortens the service life of electric machines operating under conditions of increased dustiness of the environment is the accelerated aging of stator winding insulation. The dust layer thickness on the upper part of the end winding of motors with a power of 50 kW or more ranges from 2 to 5 cm.The accumulation of dust on the surface of the IM winding insulation leads to reduced heat dissipation and local overheating of the insulation under the dust layer.The development of a method for diagnosing the causes of thermal loading of stator winding insulation and a system for thermal protection of IMs, determining the conditions for preventive maintenance, as well as creating algorithms and software for devices providing thermal protection of induction motors, is therefore a relevant task.