A Cost-Effective Nonresonant Inverter Topology for Domestic Induction Heating

Nonresonant inverter topologies are a reliable, self-protective, and cost-effective solution for induction heating (IH) appliances. In this article, a novel nonresonant inverter topology, particularly suitable for domestic IH applications, is proposed. The proposed topology achieves high output voltage levels, addressing the main drawback of nonresonant topologies compared to resonant ones, which is an increased voltage demand for the same output power. In addition, both switching devices operate against a common ground, enabling a cost-effective implementation with high power density. In this article, the proposed inverter is described, its different operating modes are analyzed, and a power control strategy is derived. A comparison with conventional resonant topologies reveals a potential cost reduction of approximately $13 \,\%$ in the main power electronics components, due to the elimination of resonant capacitors and the possibility of using more cost-effective gate drivers. Experimental results demonstrate that the output power can be seamlessly controlled from zero to $3.6 \,\mathrm{kW}$, while maintaining zero-voltage switching across a wide operational range. This ensures efficient operation with a maximum estimated efficiency of $98.3 \,\%$.