Research On Power Supply For Induction Brazing Of Solar Cells Based On Resonant Inverter

Various specifications of solar panels are formed by string welding a certain number of unit cells through tinned solder tape.The development of light and thin solar cell silicon wafers has increased the technical difficulty and product cost of solar cell welding.The application of non-contact induction brazing technology not only effectively reduces the risk of cell cracking caused by traditional contact welding,but also has the advantages of high efficiency and energy saving.It is the preferred direction for the upgrade of solar cell welding equipment technology.In this paper,the research and design of high-frequency inverter power supply based on the application of solar cell induction welding are carried out.In order to make the inverter output rated power,impedance matching design is required.A brief analysis of series resonant transformer impedance matching and third-order resonant load impedance matching is carried out,and it is determined to use a simple structure and high-efficiency LLC load for impedance matching design.The working characteristics of LLC resonant load are studied,the current and voltage relationships of multiple nodes are analyzed in detail,and the half-bridge inverter with low cost and simple control is determined according to the design index.Aiming at the problem that the natural frequency of the resonant tank circuit deviates from the working frequency of the inverter caused by the load temperature change,after studying the principle of the phase-locked loop,the phase-locked loop control is designed to verify the stability of the phase-locked loop,and The closed-loop simulation and analysis of the phase-locked loop control of the half-bridge LLC inverter power supply are carried out in PSPICE.In order to further verify the feasibility of the design scheme,related hardware circuits and digital phase-locked loops were designed,related programs were written in C language,and a half-bridge LLC high-frequency inverter power supply experimental prototype with the main control chip STM32F103 was built.The experimental waveforms were analyzed,and the correctness of the design scheme was verified by comprehensive theoretical analysis,computer simulation and experiment.