Research On Ultrasonic Motor Driver And Controller Based On PSoC3

This research activity is funded by National Natural Science Foundation of China Key Programs(Grant No.50735002).Utilizing the inverse piezoelectric effect of piezoelectric material, elastic body (stator) cangenerate vibrations in the ultrasonic frequency band, so ultrasonic motor (USM) can be actuated bythe friction between the stator and rotor to obtain motion and torque. The development of the USMrelies on the high performance driving technology.The traditional USM driver can not meet thedevelopment requirements of the USM with the single speed control method, the bad feasibility andthe limited control functions. The driver based on the way of SPWM is proposed in this paper; itsolves the limition of one single power supply and the tedious question of matching circuit, realizesthe function of motor speed control,and improves the protection fucthions of the driving system. Themain contents are as follows:1. The characteristics and development history of the USM were introduced, then the researchsituation and the present defects of the moter driver were described, the research contents ofthis paper were proposed.2. The overall design scheme of the driver was given. The forestage power supply design, thehalf-bridge converter circuit design, the pulse transformer design and matching circuitdesign were detailedly introduced.3. The spectrum characteristics of the PWM signal and SPWM signal were comparedrespectively. The digital generation method of the SPWM signal is discussed and thesimulation result was given.4. The structure characteristics of PSoC3control chip,and its advantages and disadvantages aredescribed. The software control process of the moter was given. The isolated electrodevoltage feedback circuit,the overvoltage detection circuit and the overcurrent detectioncircuit were designed. The working statuses of the moter can be shown on the LCD1602display.5. The hardware circuit of serial communication was designed.The communication betweenPSoC3and PC can be realized. Then,the control interface was developed by usingVC++,realizing the intuitive control from PC to USM.6. The key waveforms of the driving signal were measured. The appropriate parameters of the series matching inductance were selected. Ultimately the speed regulation controlexperiment was finished by using the USM driver and controller and the experimental dataswere analysed.