Development Of Semiconductor Pumped Solid State Laser Driver System

Lasers can produce a large amount of energy in a short time.As the main type of laser,solid state lasers have been widely used in various fields due to their diverse operation modes,diverse working materials and simple and compact system structure.Based on the project of the development of semiconductor pumped solid-state laser driver,this paper develops a semiconductor pumped solid-state laser driver system,which consists of high-current pulse power supply,TEC constant temperature control,Q switching circuit and system monitoring.The following works are carried out around the project requirements in this paper.1)The design of main circuit.According to the characteristics of semiconductor pumped solid-state laser,the design scheme of constant-current pulse generation circuit based on linear power source is selected,and the mathematical modeling of the circuit is presented,and the closed-loop control system is designed according to the mathematical model of the circuit.The pre-stage power circuit based on 4-switch buck-boost converter is designed.The principle of the pre-stage power circuit is analyzed,and the control method of the circuit is designed.The TEC drive circuit of the temperature control part of the drive system is designed,and the working principle of the TEC drive circuit is analyzed,and the temperature control method is designed according to the characteristics of TEC.According to the design index of Q switch of solid-state laser,RLC Q switching circuit is designed,and the operating principle of RLC Q switching circuit is analyzed.2)The design of Circuit parameter,simulation and hardware system.The parameters of the main circuit are calculated,and the RLC Q switching circuit and constant current pulse generating circuit are simulated by Pspice simulation software,and the effectiveness of the circuit is verified.The hardware circuit system with STM32F103RTC6 is designed,including constant current pulse generator circuit,Q switching circuit,TEC drive circuit,auxiliary power supply,signal acquisition circuit and RS485 communication circuit.3)The design of system software.The software development of the lower computer based on Free RTOS operating system is completed.The state machine of the lower computer software is designed.The multi-task operation of the lower computer software is realized.The operation mode of Modbus communication protocol stack is optimized.According to the design requirements of the upper computer,the upper computer software of the driving system by Qt platform is designed,including the development of the upper computer interface and the realization of the upper computer software operation function.4)System testing.Through the establishment of the experimental platform,the hardware and hardware test of the drive system are completed.The experimental results show that the drive system can complete the functions of constant current pulse generation,Q-switching voltage pulse output and temperature control according to the design index.The real-time performance of the lower computer software is relatively high,which can meet the multi-task requirements.After optimizing the success rate of Modbus communication,the upper computer software can meet the design requirements.