Design Of The Driving System Of High Power Semiconductor Lasers

With the rapid development of semiconductor technology,more and more semiconductor lasers are on the market.It has the characteristics of small size,high efficiency,low power consumption,good reliability and long service life.Therefore,it is widely used in national defense,communications and other fields.Semiconductor lasers are non-linear components,which are sensitive to temperature.The threshold current,output power and emission wavelength of semiconductor lasers are easily affected by temperature.Therefore,in the use of semiconductor lasers,the working temperature will be controlled to make it work at the optimum temperature to ensure that the semiconductor lasers can work properly.At present,the existing laser temperature control system is large and relatively expensive to purchase.Therefore,it is necessary to design a temperature control system for semiconductor lasers.In this paper,the working temperature of semiconductor lasers used in laser source is controlled.In this paper,a temperature control system for semiconductor lasers based on STM32 is designed.This paper is divided into five parts,which are the scheme design of high power semiconductor temperature control system,the hardware circuit design,the measurement and control method design,the system software design,the system test and conclusion.In this paper,the working temperature of semiconductor lasers is controlled by controlling the speed of compressors and axial fans.The control core of this paper is STM32F103VET6 of Italian Semiconductor Company.Different temperature sensors are used for temperature acquisition at different locations.The collected temperature is used as feedback for the control system of micro-compressor and axial fan respectively to adjust the speed of micro-compressor and axial fan.The hardware circuit includes STM32F103VET6 system circuit,micro compressor drive circuit,axial fan drive circuit,temperature detection circuit and serial communication circuit.Closed-loop control with feedback link is adopted in the control methods of micro compressor and axial fan.Speed control of micro compressor by PID-Smith control algorithm,and a Simple Control Algorithms for Axial Fan.In this paper,the PID control algorithm and Smith predictive compensation algorithm are introduced in detail.On the basis of hardware circuit,the software development of measurement and control system is completed by KEIL5.The interface of testing software is designed by using LabView,a program development environment of NI company,to test the temperature control system of semiconductor lasers.Finally,the control algorithm of micro-compressor is simulated and tested,which proves that the PID-Smith algorithm can control micro-compressor better.The test software proves that the temperature control system designed in this paper can make the semiconductor lasers work stably at 25 C.