Study On The Mid-frequency Induction Furnace System Of Thyristor Half-bridge Inverter And The Principle Of Energy Saving

With the improvement and development of induction heating theory and equipment,the application domain and scope of induction heating have been expounding.Along with the enhancing environmental protection consciousness of human,the high-power,low-harmonic, energy-efficient power supplies for induction heating equipment having been one popular spot among the community to research and invent power supply for induction calefaction.Because in the recent three years,domestic electric furnace companies run short of basic system theory, they can only counterfeit the products of USA's company.Therefor,in this paper,the thyristor half-bridge series resonant induction furnace system and the principle of Energy conservation are researched.Mainly work:1,Based on basic theory,the principle of induction heating is analyzed,the current distribution of the furnace and the changes of parameter are studied;The characteristics of the parallel resonant power supply is implemented,and the formula for calculating of the various parameters for the rectifier circuit,filter circuit and inverter circuit are given.2,This paper analyzes the work process of the main inverter circuits in detail and draw the current waveform of the induction loop.Each waveform of output is sin wave and anti-phase connection,called"W"wave.It transform two cycle when the Thyristor change one cycle. According to the result of the mathematical derivation and the simulation in the MATLAB/Simulink,we confirm the correctness of the analysis.3,The power adjustment of the series circuit also introduced in the paper,it changes the cycle of the waveform,called AC"PFM".Through the analysis of the trigger circuit and the protection circuit,we draw a conclusion:the characteristics of the Half-bridge series resonant inverter are stability and reliable.4,The paper contrasts the series resonant circuit and parallel resonant circuit in many facts, including main circuits equivalent circuit of loop,harmonic of wave forms power adjustment,power factors quality factor and the reliable of the circuit.5,we confirmed the theory by waveform sampling of series resonant and energy comparison tests.In this paper,based on the current waveform of the series resonant power supply,the characteristics of energy-save is proved with the help of theoretical analysis and field tests.The results of experiments show that the research here can promote the process of the development of the furnace.