Study Of All-digital Super-audio Frequency Induction Heating Power Supply

With rapid development of power electronic technology and induction heatingtechnology，and the increasing requirement of heating process for induction heating powersupply, greater capacity and higher frequency is the development direction of inductionheating power supply. The in-depth study of induction heating power supply is playing agreat role for promoting the equipment manufacturing industry and related industriesdevelopment. Therefore, the research on induction heating power supply has importantsignificance for promoting new industrialization leapfrog development.By analyzing the principle and structure of induction heating power supply, thesuper-audio frequency induction heating power supply system based on IGBT is design,including the rectifier module, power regulation module, Inverter module and load module.The three-phase full bridge controlled rectifier circuit is adopted as rectifier module, andparallel resonant inverter as inverter module. The power control for load is the mostimportant part of super-audio frequency induction heating power supply. The traditionalPID algorithm is difficult to achieve the requirements of accuracy of temperature controland anti-interference because of the complicated model of super-audio frequency inductionheating power supply system and interference factors from the load-side in actualproduction process. For this reason, this paper adopted compensated fuzzy neural networksalgorithm. Simulation results showed that the compensated fuzzy neural networksalgorithm, compared with the traditional PID algorithm, not only has good dynamiccharacteristics, but also can eliminate steady-state error effectively and improve the controlprecision of controller, and enhance the system’s anti-interference capability.This paper completed the design and implementation of hardware circuit and softwareprogramming. The system adopted TI’s DSP (TMS320F28335) as the master control chip,realized the digital phase-locked loop for frequency tracking and the protection of overcurrent or over voltage fault. By experimental verification of the function of each part, theexperimental results are given and analyzed, and the correctness of the design theory andthe feasibility of the control method are verified.