The Design And Improvement Of Single-switch Induction Heating

It is wildly used for induction heating in industry and civilian use.In civilian use,the most commonly known is the Induction Cooker,which has many advantages compared to other cookers and is popular among all the world.This paper aims to design an induction cooker,which can output power from 500watt to 10000watt continuously.There has many topologies of inverter for induction cooker.The advantages and drawbacks of these topologies have been analyzed in this paper and come to a conclusion that the topology,single-switch type ZVS inverter,is the best choice.Common low-cost single-switch induction heating has some deficiency,such as turning on without zero-voltage switching(ZVS),high pule time of capacitor(du/dt),high loss of IGBT and so on.Aiming to the above defects,in this paper,the work theory of the induction heating is thoroughly analyzed,and an essential reason of the circuit turn on without zero-voltage is obtained.A method by increasing the fixed time-delay is presented to achieve ZVS of the source,and the range of fixed time-delay is detailed analyzed and deduced in theory.Moreover,a proper scheme to realize increasing fixed time-delay is given by adding the number of comparators.A experimental platform is built and experimental results verify the correction of theory analysis and validation of implementation.In the last part of this paper,the main parameter of the system,protection circuit and system control are designed.The system is verified in the experimental results.