安装位置感应钎焊逆变器拓扑及工作状态分析

针对安装位置导管感应钎焊的特点,选取电压源串联谐振回路作为方波电源逆变器主电路拓扑,重点对串联谐振回路的阻抗和逆变器主电路工作状态进行了分析,在此基础上确定了方波电源逆变器的最佳工作状态.设计了以SG2525A为核心的准谐振频率自动跟踪电路,对方波电源逆变器的工作频率进行动态调整,使感应加热回路始终工作在略偏感性的准谐振状态,不仅确保了方波电源逆变器安全可靠地工作,而且提高了感应钎焊电源的加热效率和功率因数.

Main circuit topology and working status of inverter in on-site induction brazing of tubes

Considering the characteristic of on-site induction brazing of tubes, the voltage source series resonant circuit was adopted as main circuit topology of inverter in the square wave power. The impedance of series resonant circuit and the working status of inverter main circuit were discussed. Based on the above, the best working status of inverter was proposed. A new frequency tracking scheme, which combines the proportion integration(PI) control method with the IC SG2525A, was proposed to adjust inverter operating frequency to keep the induction heating circuit working in quasi-resonance state. This technology not only ensures the inverter safe and reliable work, but also enhances the induction brazing power source heating efficiency and power factor.