Mathematical Model for a Quasi-resonant Converter

the paper presents a mathematical model for a quasi-resonant converter. This type of converter was analyzed for an induction heating system. The system can have a series or a parallel resonant circuit as a load. In this paper we discussed only series resonant circuit load case. The proposed objectives for analyzing the operation of this system were the following: development of PSpice simulations; development of Matlab simulations; development of Simulink simulations. The operation of both configurations (series or parallel) was mathematically analyzed. Using PSpice simulation environment, the time intervals were emphasized. A system of differential equations was obtained for each time interval. We obtained a simulation interface for the circuit, by implementing the equations in Matlab. The current through the induction coil and the voltage across the capacitor were represented.