Research On Induction Heating Power Supply Design And Its Control Strategy

Induction heating technology is different from traditional heating technology.It uses electromagnetic induction principle to convert electric energy into heat energy to heat objects.Induction heating technology has the advantages of uniform heating,fast heating speed,high efficiency and no pollution.It has broad application prospects in quenching,smelting,brazing and thermal curing.Induction heating power supply is used as the core of induction heating technology,which has very important research value.In this paper,with the support of the National Natural Science Foundation of China,working mechanism of the induction heating power supply,structure selection,control system analysis,main circuit design and digital control system are discussed.Its main contents are summarized as follows:(1)This paper introduces the research background,research status at home and abroad,characteristics and applications,and development trend of induction heating power supply.According to the law of electromagnetic induction,the basic principle of induction heating power supply is summarized,which provides a theoretical basis for further study of induction heating power supply.(2)Aiming at the problem of different effects affecting heating effect in induction heating power supply system,the system characteristics are analyzed.The advantages and disadvantages of series-parallel resonant inverters are compared,the series resonant inverters are chosen as the main circuit,and the load characteristics are analyzed.(3)The control system of induction heating power supply is studied,several power regulation modes are compared and the induction phase shifting power regulation is determined as the closed-loop power regulation mode.At the same time,the phase-locked loop is introduced to realize the tracking control of switching frequency.The anti-saturation PI controller is designed to realize the stable control of the system and the main circuit is modeled and simulated.(4)The digital control system platform is built based on TMS320F28335.The experimental research on the driving pulse width waveform,power output regulation waveform,sampling current waveform,frequency tracking phase acquisition and phase-locked loop of the induction heating power supply is carried out.The experimental results show that the designed control system of the induction heating power supply can realize the stable and reliable operation.