Analysis of the harmonics losses and bearing load for motorized high speed spindle part I: Modeling

Angular contact bearings are the most popular type of bearings used in the motorized high speed spindle. An initial preload and operating-induced load control are managed to ensure its rigidity, but the centrifugal force and temperature will rise with the rapid increase of spindle speed. Although the centrifugal force and thermo induced bearings load are applied on the spindle assembly. This paper aims to study innovative structure solution of spindle and develop a new type of super precision bearings which will ensure the lifetime and high performance of spindle. Section II proposed an improved inverter output filter, for pulsewidth modulated (PWM) drive system. The proposed filter is shown to effectively reduce the power losses in the spindle. This usage of the filter can improve lifetime of bearings and gain a higher output power of the spindle. The simulations show a 20 KW, 400 Hz PWM drive system with total loss reduced 13.36%, and a 20KW, 800HZ PWM drive system with total loss reduced 15.77%. Therefore, the filter configuration is an excellent contribution for PWM drive system.