# Examining the Optimal Use of WBG Devices in Induction Cookers
## 5 Conclusions  
In this study, the optimal use of WBG power devices in domestic induction heating applications is examined. GaN HEMT is tested for different operating conditions to find optimum operating conditions and tried to answer \"When it makes sense to switch Si-based IGBTs to WBG power semiconductors\". The first step is to use WBG power semiconductors in conventional domestic induction heating conditions. In this condition, the power rating is high and the switching frequency is low; therefore, the main contributor to total power loss is conduction loss. A WBG power semiconductor whose on-state resistance is so low that its conduction loss is well below Si-based IGBTs can outperform. However, a discrete power semiconductor with lower on-state resistance than IGBT can cost too much. Using two or more switches in parallel is another solution, but this is not cost-effective either. Potential EMI problems are another issue to deal with because of the high dv/dt and di/dt ratings. As a result, the fact that a WBG power semi-conductor operates in standard domestic induction heating conditions does not make sense in terms of the total product.  
The second step is to use WBG power semiconductors in high-frequency applications with the same zone power as conventional cooktops, thanks to their superior switching performance. In this condition, we can reduce the size of passive components considerably. As a result of this, more efficient power conversion, and a slim, low-noise design can be achievable. The decreasing number of turns in induction coils and capacitors with low ESR (Equivalent Series Resistance) values contributes to total efficiency. The cost of WBG power devices can be met by other design parameters, such as passive components with lower values, heatsinks with low volumes, cooling fans with low power, and induction coils with a lower number of turns. High-frequency operation can also be effective in heating non-ferromagnetic materials such as aluminum and copper. These types of pans can be heated without complex induction coil and power converter designs due to their high operating frequencies. As a result, the usage of WBG power semiconductors in high-frequency and power conditions makes sense.  
The other operating condition is the flexi induction cooktop design with WBG power devices. Flexi cooktops can heat a pan anywhere on the glass. They use multi-inverters structure with multiple induction coils to achieve this type of design. WBG power devices, specifically GaN HEMT, can be suitable for these designs because they can switch at very high speeds. Ultra-high switching speeds can also enable planar magnetics, which is also  
Figure 21: All full-flexi measurements.  
an important advantage for increasing power density. Low power loss due to the superior characteristics of GaN HEMT could enable to design without a heatsink and a cooling fan.  
Conceptualization, A.E. and A.H.O.; methodology, A.E. and A.H.O.; validation, A.E. and A.H.O.; investigation, A.E. and A.H.O.; writing--original draft preparation, A.E. and A.H.O.; writing--review and editing, A.E. and A.H.O. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
This work was supported by Arcelik A. S. Research and Development Center.  
The authors declare no conflict of interest.