2.2 kW급 유도전동기 축계의 반응표면 분석법을 이용한 진동설계 최적화

This paper presents the vibration design optimization process for the rotor-bearing systems of kW-class induction motors using the response surface method. At first, finite element rotordynamic analysis for the initial design motor is performed to set up the initial performance criteria for the vibration design. They include maximum rotor vibration amplitude and bearing basic rating life at rated speed of 1,800 rpm. Design variables are selected to bearing locations, rotor core location, and shaft diameter given that the design limitations of other parts. As a result of main effect analysis, the bearing locations and the rotor core location have most effect on the rotor vibration and bearing life, respectively. Finally, design optimization is carried out with the objective of decreasing the vibration and increasing the life, and the result indicates that the vibration gets reduced by 45% and the life is maintained. Optimized design has small bearing span, identical distance between the center of gravity and two bearings, and large shaft diameter, thus exhibiting low vibration and high durability characteristics.