Research On Gimbal Drive And Control Technology Of Micro Control Moment Gyro Using Ultrasonic Motor

Ultrasonic Motor(USM)is a new kind of macro-special motor by using the inverse piezoelectric. USM is used as Driving System for gimbal of a micro Control Moment Gyroscope(CMG) in this study. The main work focus on the following aspects:Firstly, the state of the art of CMG, USM and theirs control techniques are introduced, as well as the principle of USM. Then the analysis model and equivalent electrical model are given and discussed. The model of USM is determined by Area Method and the Frequency-Speed model is obtained. The Least-Square method is employed to optimize the experiment data and the results show that it meets quite well with simulation.Secondly, the frequency regulation control characteristics of USM are analyzed. The principle of temperature rising phenomenon in running state and its resonant frequency drift effects on motor speed control. Solitary pole feedback control law is used to compensate the resonant frequency drift effects. The control system of USM is designed based on parameter model, and PID is employed here to control the speed of USM.Thirdly, a hardware test platform for the driving system of Micro-CMG gimbal is established based on PXI equipment, such as thePXI-8108 embedded processors, and FPGA-based technology PXI-7851 Reconfigurable multifunction data acquisition card. The signal pre-driver circuit, the push-pull transducer circuit are designed, as well as a special transformers and impedance matching circuit. Based on these circuits, an ultrasonic motor driver is developed.Then a new kind of software is developed to support the Micro-CMG frame driving experiments based on virtual instrument development platform Lab VIEW. A new high-precision PWM signal generation module is developed with the precisionreaching0.1Hz, fully meet the needs of ultrasonic motor FM control. Speed measurement module is developed by FPGA programming and the control law is actualized by G language. A kind of model-determine software for USM is also developed.At last, some experiments are conducted based on the previous control software and driving circuits, such as ultrasonic motor open loop drive and closed-loop speed control.