Induction Motor Structure Design to Reduce Vibrations With Numerical (FEA) and Experimental (VA) Techniques

Abstract

The resolution in the design of the machine structure can control vibrations that increase the lifespan of the induction motor (IM). This is feasible by retaining the machine’s vibrations within acceptable ranges. To reduce these vibrations of an aged machine a vibration analyzer (VA), finite element approach (FEA), and experimental modal technique (EMT) are applied to an induction motor. The test on stator windings (SW) with global mode revealed that the windings in slots 7 and 8 are deformed. ANSYS software was used to model the machine with FEA numerically to predict the vibration velocity (VV) and found 18.3 mm/s. The vibration analysis was applied to IM and noticed a vibration velocity of 10.6 mm/s, indicating both the numerical and experimental vibration velocities are greater than 5 mm/s. This can reduce the reliability of the motor as per ISO Standard 10816 and cannot meet industrial needs. The test machine was numerically redesigned with a 6-hole reinforced frame and raised to 0.1 cm in thickness to reduce the vibrations then VV was recorded as 2.9 mm/s. Vibration analysis is carried out experimentally while the machine windings are tightened after modification and the vibration is 3.2 mm/s. Finally, both numerically (84.15%) and experimentally (69.81%), the test motor’s vibrations are reduced, enhancing the test motor’s reliability to meet industrial requirements and minimizing the plant’s revenue cost.

Keywords

• Fault diagnosis
• induction motor
• modal test
• finite element analysis
• vibration analyzer
• deflection shape