# Examining the Optimal Use of WBG Devices in Induction Cookers
## 1 Introduction  
Induction cooking applications have been drawing attention due to their superior performance, such as fast heating, efficiency, controllability, cleanness, safety, and lower carbon emissions, for a long time. The working principle of an induction cooktop is based on Faraday's Law. It produces a high-frequency magnetic field with the help of a power electronics converter and an induction coil, and then this magnetic field induces eddy currents directly beneath the ferromagnetic pan. As a result of this process, joule and hysteresis losses heat up the pan [1]. The basic building block is shown in Figure 1.  
Meanwhile, there are some criteria that define the performance of an induction cooktop. High zone power ratings, high performance, total height of the product, and silence are the most prominent ones. These criteria are directly related to power semiconductor switch losses. All the commercialized induction cookers have been using IGBTs for a long time. There are different types of IGBT technologies, some of which are directly produced for resonant applications. IGBTs can be preferred thanks to their low saturation voltage (\(V_{CE_{sat}}\)), which results in low conduction loss; however, they have limited switching capacity because of the tail current they have during turn-off. Most modern induction cooktops operate between 18 kHz and 50 kHz, and their resonance frequency is between 18 kHz and 20 kHz [2; 3; 4]. There are different research papers about WBG power semiconductors that show that WBG power semiconductors are applied to domestic and industrial induction heating applications. WBG power semiconductors are evaluated in different power electronic systems and compared with Si-based designs in [5], while Si-based switches are compared with WBG power switches in [6]. There is also a variety of research that is directly related to induction cookers. Si IGBT, GaN HEMT (Gallium Nitride High Electron Mobility Transistor), and SiC MOSFET (Silicon Carbide Metal Oxide Semiconductor Field Effect Transistor) are compared in [7] for a 2.0 kW power rating. Refs. [8; 9] compared SiC MOSFET and SiC JFET (Junction Field Effect Transistor) in terms of power losses. In these works, power ratings range from 200 W to 1800 W, while switching frequencies change between 45 kHz and 125 kHz. Ref. [10] compares normally-on SiC JFET and Si IGBT in a series resonant half-bridge converter at 2.4 kW power rating up to 500 kHz switching frequency. All SiC power semiconductor technologies are tested and evaluated for induction cookers in [11]. Normally-on and normally-off SiC JFETs, SiC BJT (Bipolar Junction Transistor), and SiC MOSFETs are tested and compared from different perspectives. SiC BJT power switches are evaluated for a new ZCS (Zero Current Switching) converter in [12; 13]. Although most of the research focuses on series-resonant half-bridge converters, there are also papers related to single-ended quasi-resonant converters. Refs. [14; 15; 16] apply SiC power switches to single-switch resonant converters. WBG devices enable us to configure induction cooktops in different ways, which are hard to design with Si-based power semiconductors. Refs. [17; 18; 19] use GaN HEMT power switches and design full-flexi high-segment induction cooktops. Ref. [17] uses GaN HEMT in 2 MHz switching frequency and loads power up to 15 A. It also considers thermal perspective and layout design. Ref. [18] elaborates on full-flexi induction cookers. It simulates 800 W load power for different switching frequencies ranging from 100 kHz to 500 kHz. Ref. [19] implements GIT (Gate Injected Transistor) GaN HEMT technology in induction cookers at 2.2 kW power and 50 kHz-100 kHz switching frequencies. A series resonant half-bridge converter is evaluated at different operating conditions. Measurements are inspired by real induction cooker operating conditions. The power rating is increased up to 3.7 kW, while the switching frequency ranges from 20 kHz to 100 kHz.