Design of Thermally Constrained High-Frequency Induction Heating System

One of the most prominent application areas of induction heating principle is for sealing of caps of plastic and glass containers. It is increasingly being used to seal containers with extremely wide range industrial products. The process ambience around the controller for sealing of bottles containing different types of products could be different. Such prospects, often, could act as constraints for design of power controllers. Dust prone environment prevailing in processes such as for sealing nutraceuticals, coffee, a few pharma products, etc. recommends use of air-tight enclosure. It does not have any ventilation, even the natural air movement inside or the free convection is restricted. This article proposes that the internal convection could still be made effective by creating requisite buoyant force where both power converter topology and component engineering could play important roles. The topology should optimally reduce the power loss and surface temperature of components should be high. The proposed idea has been validated by designing a zero-ventilated 1.5 kW, 50 kHz induction heating system that includes the induction coil head.