Research On Intelligent Temperature Control High Frequency Electromagnetic Induction Heating System

As a new-style method of heating, induction heating has many advantages compared with traditional heating. With the development of national industrial process and the growing importance of environmental protection, induction heating as a high technology and low environmental pollution heating method, has been widely used in industrial heating. The core of induction heating technology is electromagnetic induction heating power, its internal rectification and inverter is the focus of the study. With the development of power electronic technology, And the emergence of new high frequency and high power semiconductor devices, which make the modern induction heating power supply gradually to the high power and high frequency. Inverted power switch device made up of IGBT is an important direction for the development of electromagnetic induction heating power supply, so it is necessary to study the internal structure and control method of induction heating power supply.In this paper, the main circuit structure, working principle and parameter design of voltage type series induction heating power supply are introduced in detail. We present two control methods, which are limited bipolar control and frequency tracking control, and analysis the advantages and disadvantages of them. By adopting the frequency tracking control method, we successfully design a series resonant heating power supply of 30kW/17kHz. Three phase bridge controlled rectifier circuit are made up of SCR, and design the SCR digital trigger pulse based on single-chip microcomputer, by changing the angle to adjust the output power. The inverter circuit adopts IGBT to form the full bridge circuit, and the load circuit adopts series resonant structure. SG3525 chip is used to achieve the frequency tracking control of the load, and the phase locking is achieved, and the impedance matching of the load is realized, and the power factor is improved. MATLAB simulation and experimental results show that the induction heating power supply is in good working condition. And finally the intelligent, temperature control system of high power induction heating system is designed.