Adapting of Non-Metallic Cookware for Induction Heating Technology via Thin-Layer Non-Magnetic Conductive Coatings

Abstract

We analyze the feasibility of heating non-metallic cookware, unappropriate for heating by means of induced currents, with the purpose of extending the applicability range of the current induction heating cooktops. In order to turn materials as glass, ceramic, wood or plastic into suitable for the induction heating technology, we propose the use of thin layers of a metal (not necessarily a ferromagnetic material) which can be deposited on a surface by means of a thin or thick layer technology. For this purpose, the inductive performance of these layers is investigated by means of an analytical electromagnetic model, finite element simulations and experimental measurements. Calculations point out that for a specific induction arrangement working at a fixed frequency, it exists a thickness which maximizes the induction efficiency for each layer material. The suitability of this result is tested by means of a set of samples with copper thin layers whose thicknesses range from one hundred of nanometers to tens of micrometers, which are implemented using a phase vapor deposition (PVD) technology. The obtained induction efficiency and equivalent resistance are compared with those obtained with conventional ferromagnetic materials. As a proof of concept, the inner and outer bottoms of two glass pots are covered with a copper layer of 2 µm, and 1.5 µm, respectively, and 1 kW is inductively supplied by means of a series resonant inverter, reaching the boiling water conditions. INDEX TERMS Eddy currents, energy efficiency home appliances, induction heating, impedance matching, thin layer.

Induction Heating in Domestic Cooking and Industrial Melting Applications: A Systematic Review on Modelling, Converter Topologies and Control Schemes

“…It was good for a multi-output system but bulky for single-load applications. The adaption of non-metallic cookware for thin-layer non-magnetic conductive material was proposed in [113]. The inductive performance of the thin layer was investigated via an analytical electromagnetic model, finite element simulations and experimental measurements and it was observed that the proposed system is well-suited for non-ferro magnetic pots.…”

EMI Reduction Via Resonator Coils in Glassless Integrated Domestic Induction Systems

“…Moreover, dissipative media (aluminum and load) are modelled as an Impedance Boundary Condition (IBC). This model is valid when the skin depth of fields is smaller than the thickness of the media, as occurs in the aluminum and ferromagnetic vessels at the operating frequencies [15]. -Real windings and their cabling structure are modeled by an ideal rectangular cross-sectional constant current density of value J = nÎ/S w , where n is the winding's number of turns, S w is the cross-sectional area of the winding andÎ is the current amplitude.…”

“…Nowadays, an intense research activity is still detected in this field, mainly focused on improving the performance and reducing the cost of current cooktops. This research activity encompasses power electronics converters for an efficient use of the energy [2], [3], coil arrangements for the improvement of the user flexibility [4], [5], [6], load identification systems [7], [8], sensing functionalities [9], [10], [11], inductor PCB implementations [12], magnetic materials [13], robotized mobile inductors [14], or adapting non-metallic cookware for induction cooktops [15].…”

A comprehensive overview of power converter topologies for induction heating applications

“…[1][2][3] The IH technique has witnessed rapid development over the years. 4 In the late 1980s, with the advent of semiconductor devices, IH technology contributed in various applications, such as domestic, industrial and medical fields. [5][6][7][8][9] The typical IH set-up is shown in Figure 1.…”

“…Induction heating (IH) is the booming technology that has replaced conventional heating techniques, as the latter possess inherent advantages of being safe, non‐contact heating, non‐contamination of the material, zero pollution, compact size, higher efficiency, etc 1‐3 . The IH technique has witnessed rapid development over the years 4 . In the late 1980s, with the advent of semiconductor devices, IH technology contributed in various applications, such as domestic, industrial and medical fields 5‐9 .…”