| Energy conservation is an important theme recently. High-power induction cooker has the advantage of electric efficiency, heating speed, easy operation, which has broad application prospects. In this thesis, the key technology of the appliance is researched based on half-bridge resonant circuit, to solve the short of the existing cooker power's small power and poor stability.It analyzes the working principle of high-power induction cooker and forms to be used in inverter circuit, then design the parameters of the inverter circuit, including the IGBT selection, resonant inductor and capacitor design. It also designs IGBT dead zone circuit and intelligent hardware protection circuit to protect the switching devices. Finally it designs the control software, including the functions of each module and the power module control.IGBT inverter circuit is the core components. It researches the IGBT characteristics and power consumption calculation, and designs the general drive circuit and the selection of parameters and gate resistance, focusing on protection of induction cooker. Finally it researches dynamic and static characteristics of IGBT for parallel expansion appliance and proposes the method of gate compensation to balance the dynamic performance. Simulation results show the good effect of this method.Research has been done bases on the transformer load models. As the model can not reflect changes of load, the paper proposes a dynamic web-based impedance load model. The experimental data and software simulation verify the accuracy of the model which builds the relationship between frequency and power. Finally, while the load changes with temperature, it proposes adaptive temperature control of the appliance. According to the input and temperature feedback, it adaptively implements constant power control based on dynamic load model and constant temperature PI control. Experimental results show the control method in the energy and heating rate has a good effect.
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