Dynamic Force Calculation and Experimental Verification of Axial Bearings

Abstract

The axial bearing does not contain a laminated piece; so its dynamic performance is poor and often does not meet the load requirements. To accurately assess axial bearing performances during the design stage, it is necessary to accurately calculate the dynamic characteristics of the bearing, including amplitude, phase, and other parameters. Traditional studies have generally used the magnetic circuit method (MCM) or the finite element method (FEM) to analyze the dynamic performance of bearings, and few experimental measurements are carried out. Some experiments use a Guess meter to measure the magnetic field at local locations without directly measuring the electromagnetic force. In this paper, the dynamic force of axial bearing is measured by experiments, and the finite element calculation with Ansys Maxwell is carried out to study the influence of the gap, resonance, and other factors on the electromagnetic force. The comparison reveals a significant error in the calculation method using the initial gap because the gap between the stator and rotor changes with the dynamic force in the experiment. In this paper, the calculation method of “analyzing the dynamic performance of the bearing with the actual gap after the DC component is energized as the calculation gap” is proposed, which significantly reduces the calculation error and can ensure that the calculation error of amplitude and phase within 100 Hz is less than 5%. The method is of great significance for the engineering application of axial electromagneticbearings.