Research On Ultrasonic Metal Welding Power Supply

With the development of industrial processing technology,the emergence of new materials has promoted the development of processing technology,of which ultrasonic metal welding technology is a new type of material processing technology.Ultrasonic metal welding overcomes the shortcomings of"oxidation"and"spatter"of resistance welding,with high welding efficiency and little damage to the weldment.Since the stability of domestic welding power source is not good enough,it is very important to research and develop a stable and efficient welding power source.First,this article briefly describes the research background and significance of ultrasonic metal welding power sources,analyzes the current research status of ultrasonic metal welding power sources domestic and foreign;introduces the difference in principle between ultrasonic metal welding and ultrasonic plastic welding,and makes a theory of welding mechanism Analysis and finite element simulation.The key parameters of the current ultrasonic metal welding power supply are summarized,and the quality evaluation index of welding parts is given according to the actual welding requirements.Secondly,detailed analysis and calculations were made from the topological selection of the main circuit of the ultrasonic metal welding power source and the calculation of key parameters.The electrical simulation of Saber verified the output of the power circuit.The function of the sampling and conditioning circuit conforms to the theoretical design and satisfies Actual use requirements.Thirdly,L₂ matching network is proposed based on the equivalent model of the classic transducer,which uses the high voltage generated by the LC resonance to drive the transducer to work.Through the analysis of the impedance and frequency characteristics of the loaded transducer,the basis for the frequency tracking of the loaded transducer is obtained,which is verified by simulation and experiment.Considering that the traditional fixed step length is not fast enough for frequency scanning,a combined frequency scanning algorithm of"minimum current method"and"phase comparison method"based on the idea of dichotomy is proposed,Sweep time is greatly reduced.According to the loading characteristics of the transducer,a frequency tracking algorithm is designed,and the accuracy of frequency tracking reaches 1Hz.Summarized three common energy control methods,and designed a new energy control algorithm.Finally,an ultrasonic metal welding test bench was built,and the waveforms and data of the key points of the self-developed ultrasonic metal welding power source were measured,further verifying that the function of the prototype can meet the requirements of use;the ultrasonic metal welding in different welding time,Welding quality analysis under the conditions of welding pressure and welding amplitude yielded the technological parameters of ultrasonic metal welding.