Design and realization of a new AC-AC converter for household induction cooker

In induction heating systems, half bridge and single switch quasi resonance converters are widely used depending on the balance between cost and efficiency. When the latest studies on induction technology are examined, multi-coil and direct AC-AC designs come to the fore. The main reason for using AC-AC resonance converters is to reduce the number of semiconductors in the conduction mode. In addition to single-coil topologies, it is possible to improve heat dissipation by modern design with multi-coil topologies. The latest technology of the induction heating technology is AC-AC converter designs which can feed more than one source coil. However, these designs have some disadvantages. Some of the multi-coil structures are designed with the help of electromechanical switches. The electromagnetic relay connected to the coil group to be heated is activated and heating is provided. The relay increases both circuit dimensions and costs, causing the user to hear the audible mechanical sound. When the relay is not used, the selection of the number of coils to be heated is provided by using semiconductors as controlled diodes. As a result, the total number of active semiconductors used in the circuit increases, the cost increases and the efficiency decreases. When designing multi-coil structures, one of the half-bridge or quasi resonance circuit topologies must be selected. In the literature there is no circuit collecting both circuits in the same topology. In this study, it is aimed to develop a new multi-output AC-AC converter in which two different power topologies can be applied, namely half bridge serial resonance and quasi resonance by using a single converter, in which the converter problems listed above are solved for circuit topologies used in domestic induction heating hobs. The physical location of the pan as the selection criteria of the working topology, the power level to be transferred to the pan and the total number of pans to be heated can be specified. In addition, the proposed converter compared with the classical converter in the literature in term of the semiconductor quantity, efficiency and total harmonic distortion. Both the operating modes of the proposed converter and the conventional multi-coil AC-AC converter were compared for efficiency. For this purpose, first of all, simulation studies and output power related efficiency analysis were performed. After that, the simulation studies and the values obtained as a result of the implementation of the circuit were compared. The design is made in such a way that three coils can be supplied simultaneously from one source. Except where the single coil is energized; The proposed converter is more efficient than the conventional converter for all output powers in half-bridge operation. In addition, the harmonic currents of the proposed converter are below the limits set by the standards.