Displacement control of water hydrostatic thrust bearing by hybrid use of constant resistance restrictors and flow control valve

摘要

Displacement control of a water hydrostatic thrust bearing is considered. Hybrid use of conventional constant resistance restrictors and a commercialized flow control valve controlled by applied electrical voltage is applied to the bearing control. A feedback control system is then designed for the water hydrostatic bearing system. The performance of the control system is tested experimentally. The result shows that positioning accuracy of 0.2 micrometers can be achieved. Infinite stiffness of the bearing is also successfully achieved. Furthermore, the designed control system reveals the excellent control performance against external load changes.