Research On Driving Method Of Fast And Ultra-precision Macro/Micro Motion

With the fast develop of manufacturing technology of ICs and opticalcomponents, the requirements of manufacturing machines increase higher andhigher and also make higher demands for precision motion system, which is one ofthe most important parts of high quality manufacturing machines. The most popularmethod in precision motion driving is Macro/Micro dual-drive, implementing alinear motor to drive macro motion and a voice coil motor to drive micro motion.As the inner loop of motor control system, current loop plays a important role inimproving a motor’s performance. Therefore, in this paper, a DTC method for linearmotor driver, called double-updating DTC (DUDTC), and a linear driving methodfor voice coil motor (VCM) are presented. Both methods have been tested in aMacro/Micro motion system.Firstly, starting from the principle of a digital driving system for PMSM basedon FOC and SVPWM, according to the analysis of dead time effect, a DTC method,called double-updating DTC, is presented.Secondly, a linear driving proposal for voice coil motor is present, accordingto the loop bandwidth and ripple requirements of micro motion driving.Thirdly, based on the analysis and simulation of proposed methods, a double-updating DTC module in TMS320F2812and a linear driving circuit for VCM weredesigned.Finally, experimental analysis has been taken on the macro/micro drivingsystem, which implements the DUDTC module and the linear driving circuit. Thephase current of PMSM and the winding current of VCM have been acquired andanalysed. Experimental results show that the DUDTC method decreases harmonicsof PMSM phase current by50%and the VCM current loop has a bandwidth of3.5kHz because of the use of the proposed linear driving circuit.