The Key Technology Research Of Induction Heating For The Large Workpieces

The principle of the induction heating is to produce eddy current in the heatedwork piece by electromagnetic induction heating method depending on the eddy currentenergy to heating purpose. With the development of the induction heating theory andthe technology, the technology of the induction heating has been used industrial fields.However the traditional design method based on the test is not only time-consuming,but high cost. So it is very important to study the induction heating numericalsimulation. Now many researchers have begun to research the method of the inductionheating numerical simulation, also made certain achievements. In the paper, we havedesigned the induction heating power supply by the closed loop temperature and powercontrol method, established the finite difference calculation model, and realized the45#steel cylindrical shape large work pieces induction heating process temperaturecalculation, all of these based on the PWM control technology. The full text is dividedinto four chapters:In the Chapter1, the background and the significance of the study are firstlydescribed. And then the research work of the domestic and foreign scholars done ininduction heating power supply and numerical simulation are summarized. Finally themain research contents of this paper are summarized.In the Chapter2，firstly the main circuit structure of the induction heating powersupply is analyzed. And then the structure and working condition about the inverter isdetailed described. All of these decide the main circuit should choose the voltageinverter as the power supply. The power regulation of the power supply concludes manymethods, but we design the power supply by PWM wave method. Then， thetemperature control process of the induction heating system is analyzed. Finally, itrealizes the closed loop control of the power output power and temperature, all of thesebased of the digital PI control scheme. In the Chapter3, the heating numerical simulation general calculation model isdeduced according to the basic theory of heat transfer. Then the one-dimensional finitedifferent model and two-dimensional finite different model are established by thecontrol volume method and finite difference method, also analyzes the theory and theboundary about the induction heating. Finally, all finite difference models aresummarizes in the induction heating system.In the Chapter4, firstly the induction heating experiment system has been set upfor the large cylindrical shape work pieces with the material of45#steel. Then thesoftware system flow charts that used in the induction heating finite difference modelcalculation and the methods that the key problems during the induction heating processhave been given. At last, comparing the actual temperature measurement, thetemperature distribution of the discrete element is analyzed.Finally, the full text was summarized, and the induction heating equipmentoptimization and numerical simulation are new methods.