Browsing by Author "Yilmaz, N."

Now showing 1 - 3 of 3

Open Access
All-surface induction heating with high efficiency and space invariance enabled by arraying squircle coils in square lattice
(Institute of Electrical and Electronics Engineers, 2018) Kılıç, Veli Tayfun; Ünal, Emre; Yilmaz, N.; Demir, Hilmi Volkan
This paper reports an all-surface induction heating system that enables efficient heating at a constant speed all over the surface independent of the specific location on the surface. In the proposed induction system, squircle coils are placed tangentially in a two-dimensional square lattice as opposed to commonly used hexagonal packing. As a proof-of-concept demonstration, a simple model setup was constructed using a 3 × 3 coil array along with a steel plate to be inductively heated. To model surface heating, a set of six locations for the plate was designated considering symmetry points. For all of these cases, power dissipated by the system and the plate's transient heating were recorded. Independent from the specific plate position, almost equal heating speeds were measured for the similar levels of dissipated energies in the system. Using full three-dimensional electromagnetic solutions, the experimental results were also verified. The findings indicate that the proposed system is proved to enable energy efficient space-invariant heating in all-surface induction hobs.
Open Access
Mode separation and direction of arrival estimation in HF links
(Wiley-Blackwell Publishing, 2003) Arikan, F.; Yilmaz, N.; Arıkan, Orhan; Miled, M. K. B. H.
Estimation of arrival angles and incoming signals is a challenging problem for HF channels where the signals are correlated and the separation between the signals can be as low as a couple of degrees. In this paper, a new algorithm, Multipath Separation- Direction of Arrival (MS-DOA), is developed to estimate both the arrival angles in elevation and azimuth and the incoming signals at the output of the reference antenna with very high accuracy. The MS-DOA algorithm provides reliable angle and signal estimates even with small separation of arrival angles and for low SNRs. The minimum number of antennas that are required by the algorithm is only one more than the number of incoming signals. In a narrowed down region of interest and for a few incoming signals, the computational search time for MS-DOA is only a couple of minutes in a Standard PC.
Open Access
Strongly coupled outer squircle-inner circular coil architecture for enhanced induction over large areas
(Institute of Electrical and Electronics Engineers Inc., 2016) Kilic V.T.; Unal, E.; Gonendik, E.; Yilmaz, N.; Demir, Hilmi Volkan
This paper reports a newly designed class of strongly coupled planar coil structures for the purpose of enhanced induction over large areas. These new architectures feature a squircle shape at the outer rim with rounded corners and straight sides evolved into a fully circular shape in the inner side, which proves to be essential to achieve high efficiency in arrays and all-surface inductive heating. As a proof-of-demonstration, a simple inductive heating system composed of a pair of side-by-side placed coils was constructed together with a ferrite layer. Experiments were repeated for 0° and 180° phase differences between coil currents. Here, the system efficiency was shown to be increased overall by 37.4% using outer squircle-inner circular coils instead of conventional circular coils. This comparative study indicates that the proposed coil architecture offers the potential for large-area, fast, and phase-insensitive inductive heating with high efficiency.