Experimental verification of the method of diagnosis of eccentricity of the rotor of the induction motor

Induction motors are the most common electrical machines. One of the most common mechanical problems of the induction motor is the eccentricity of the rotor. The purpose of this study is to establish links between the eccentric rotor and the change of rotor speed at idle and under load transient modes. For the experimental studies we used the experimental setup, which includes a test asynchronous motor brand AIR90L4U2 disc orifice, working machine, power supply, sensor, photoelectric sensor with a chopper, analog-to-digital converter the ZET 210, a personal computer with the necessary software collection, imaging processing, and data storage. When you start getting diagnosed motor pulsating signal from the photoelectric sensor, convert it with the ADC and fed to a computer, where with the help of software and Mathcad 14 ZETlab pulsating signal is converted to the dependence of the frequency of rotation of the rotor from time to time. The experiments were conducted in an idling mode, and with the additional torque on the shaft. The results of experimental studies of the induction motor at various values of the eccentricity of the rotor (19, 27, 33, 43, 57 %). As a result of experimental studies it was found that the eccentricity of the rotor is directly proportional to the difference between the amplitude of the change in the speed tests both under load and at idle mode with the reliability of approximation R 2 > 0,92. Diagnosing engine inertia shaft allows you to get more reliable results, and the use of the photoelectric sensor reduces experimental error of up to 1,5 %>.