Ultra-high-speed Electric Spindle Of Machine Tools And Its Vector Control Method

The background of rapidly developed UHSM(Ultra High Speed Machining) technology is introduced and the key function of the UHS(Ultra High Speed) motorized spindle to UHSM is discussed in the thesis. After analyzing international technology status and trend of the UHS motorized spindle study, we research the core technologies related to the UHS motorized spindle in detail, such as optimized design of the motorized spindle structure, high speed bearing technologies, oil-gas lubication technologies, precision machining and assembly technologies, design and manufacture technologies of the built-in frameless motor etc. Then the digital simulation of the motorized spindle sensor-less vector control system is studied thoroughly.As a modern design method, computer simulation technology can shorten development cycle, reduce development costs and increase ratio of success in development of a sensorless vector control system. It is an indispensable way.We build the simulation model of the whole vector control system in MATLAB/Simulink. To get excellent dynamic and static performances, both speed and flux loop control are adopted in the system. The system uses hybrid flux model to make the rotor flux constant during full speed range. To obtain high reliability, the system uses a speed observer instead of a speed sensor to measure speed value of the spindle in the control system of UHS motorized spindles, and speed observer based on reactive power MRAS(Model Reference Adaptive System) is brought forward so as to increase speed estimated precision and robustness of the system against parameters variety.The study makes simulation experiments under different operating mode, and the results prove the correction and reliability of the simulation model of this sensorless vector control system based on reactive power MRAS speed observer.