Control And Implementation Of Stepper Motor For Space Optical Remote Sensor

The remote sensing technology is the core technology of space-based observations, space optical remote sensing plays a huge role in terms of national security, weather forecasting, disaster monitoring. Stepper motor has widely applicative in the field of space remote sensing because of the advantage of high open-loop control precision, control simple, better location accuracy, reliability, small size, and light weight.Under the study of the applications in space remote sensing of the stepper motor control, several stepper motor control method are introduced, combined with a focusing mechanism specific works, the impact to stepper motor performance of speed control and subdivision control is studied, and the conclusions can be derived that speed control can improve the response speed of the stepping motor and the subdivision control can improve the accuracy of the conclusions.Open-loop and closed-loop circuit of the stepper motor unipolar drive mode are designed based on the study of Hybrid stepper motor; the push-pull transistor connected is application to drive power switch, then the power switch can word in the high-frequency pulse. The sampled and feedback of current value of each winding reduce the wave of the winding current. By opto-isolated analog circuits and digital circuits, the reliably work of circuit is improved.To solve the problem that stepper motor rapid start and stop without losing step in high-frequency, based on the study of two motor acceleration and deceleration control method, the exponential control scheme is given, to achieve stepper motor stability, rapid acceleration and deceleration control. In order to solve the problem that the exponential type control curve can’t fully utilize the output torque, a method of the stepper motor lift speed control method based on torque-frequency curve is given which optimize the lifting speed process, reduce the accelerating and decelerate time, and the rapid start and stop of stepper motor is achieved.In order to solve the problem that unstable export torque of stepper motor a nd larger step angle,a method of current vector constant amplitude uniform rotation subdivision driver is given, this method is implemented based on FPGA completed with PWM, and the accuracy of stepper motor is improved.