Design of YAG laser welders controlled with pulse wave shaping and laser power feedback

In order to improve the stability of the output power of the laser welder,a rear optical detector was installed to feedback the output laser power signal to the control unit,making a closed loop control system.Also,a phase compensation signal was added to the laser power signal to increase the control accuracy.In addition,the control function of pulse wave shaping was used to extend the application of the laser welder.Experiments showed that the laser power fluctuation was less than 3%.Compared with 8% laser power fluctuation of the traditional laser welder,the control accuracy was improved greatly.The actual welding experiment has verified that the welding quality can be improved by changing the waveform of the laser power.