Research On The Resonant Circuit And Load Matching Of The Series Inverter

In this paper, we mainly researches on the inverter resonant circuit and load impedance of the series resonant induction heating power supply. Induction heating technology for its energy saving, pollution-free and high efficiency in machining has been widely used. With the development of computer technology and the IGBT devices, super audio frequency induction heating power became the focus of the study.First, this paper gives a detailed analysis and comparison of the advantages and disadvantages between parallel resonance and series resonance, the series resonance inverter is selected because it is more suited to the practical issues. To the induction heating power supply of PFM,this paper designs the main circuit and chooses the parameter of electronic components. By analyzing and comparing the load matching scheme, especially for transformer matching program, we obtained transformer design parameters, results show that the value is consistent with the experience.The control circuit of inverter is able to directly affect the induction heating device safe and efficient. This paper forms the double-closed-loop control system based on the SG3525, this strategy regulating the size of the power by the outer ring, inner ring is guaranteed work in the weak emotional state. The control circuit design is given including the PI regulator and Limit-phase part. While in the MATLAB platform the control circuit is simulated, the result proves that the PFM control circuit is more accurate, more reliable.We designed and simulated the IGBT drive circuit based on the common drive circuit, the result shows driving waveforms good effect. Some buffer circuit strategy are presented and simulated based on the detailed analysis and calculation. This paper gives the comparison of the losses of power devices and buffer resistance, from which selects best of the snubber circuit. At last, this paper gives some of the test waveforms, and compares to the simulation, shows that the theoretical research and design is correct. At last of the work, we give a brief summary and the next work plan.