Design Of Stepper Motor Control Circuit For Satellite-borne DOAS Based On FPGA

Remote sensing is an important and effective method in atmospheric environmental monitoring and the spectrometer technology is a kind of methods to realize it.Differential optical absorption spectroscopy(DOAS)is a type of spectrometers.There are three optical paths in the DOAS and two rotating parts are utilized in it to switch the paths.The rotating parts are driven by stepper motors and the design of driving circuit will be discussed in this paper.This circuit controlling stepper motors in a wide range of moment and meets the special requests of space equipments.The circuit utilizes FPGA as the core control chip and LMD18200 as the driving chip of stepper motors.On the basis of a description of the circuit,the problem of the increase of resistance moment and the solutions of output moment adjustment in space equipments by controlling current in windings and impulse frequency are both discussed.The real tests verified that the design's range of controlling output moment matches the requests of space equipments.The wide adjustment range of output moment is the technical innovation of this design.The first part is introduction.This paper mainly introduces the key parts of this design including stepper motors,FPGA and Hall proximity switch.The introduction includes the history,working principle and development status at home and abroad of these devices.This part paves the way for later elaboration.The second part includes the requirement analysis of the space equipment and the design,implementation and test of the circuit.Including the overall design of the circuit and communication instructions.Design,selection and peripheral circuit of FPGA and motor driving chip are also stated in this part.Then,the principle and implementation of moment adjustment are presented as well.The final test results of the prototype are shown in the end of this part.The third part introduces results of this design and future development.Including the work that needs to be done in the future,and the application in other projects.The design delivers a lot of versatility,not only can be used in space equipment,but also widely used in applications of four phase two wire stepper motors.