Extraction of inductances for coupled coils in wireless power transfer

Abstract

Wireless power transfer is one of the hot research areas of electrical engineering in last decade. The most important component in a wireless power transfer system, which dictates the transferred power level and system efficiency, is magnetically coupled coil pairs. Correct characterization of the coils is extremely important for choosing or designing the right electronic circuitry and compensation compontents.  In this paper, three different methods for extracting the self- and mutual-inductances of coupled coil pairs are prensented. A cross-shape coil pair is fabricated and measured using both an RLC meter and a network analyzer. Then, these three methods are utilized for extracting the inductances and the extracted inductance values are compared. The agreement in the extracted inductance values show that the presented measurements and extraction methods can be safely utilized for characterizing the magnetically coupled coils for use in wireless power transfer systems. 

Keywords

• Wireless power transfer,magnetic coupling,coil

Kablosuz güç transferinde manyetik bağlaşımdaki çevrimlerin endüktanslarının çıkarımı

Abstract

Kablosuz güç transferi son yıllarda üzerinde yoğun olarak çalışılan alanlardan biri durumundadur. Kablosuz güç transfer sistemlerinde aktarılan güç seviyesini ve güç transfer verimliliğini belirleyen en önemli bileşenlerden biri manyetik bağlaşımdaki bobinlerdir. Bu bobinlerin düzgün şekilde karakterize edilmeleri, verici ve alıcı taraftaki devrelerin ve kompanzasyon elemanlarının seçilmesinde hayati öneme sahiptir. Bu çalışmada kablosuz güç transfer sistemlerinde kullanılan bobinlerin (coils) öz endüktans (self-inductance) ve ortak-endüktans (mutual enductance) değerlerinin üç fraklı yöntemle çıkarımları verilmektedir. Üretimi yapılmış bir artı-şekilli bobin çifti, aralarına çeşitli mesafeler konularak bir RLC metre ile ve network analizör ile ayrı ayrı ölçülmüş ve ölçüm sonuçlarından endüktans değerleri çıkarılıp karşılaştırılmıştır. Karşılaştırılan sonuçların uyumu, bu makalede özetlenen ölçüm ve yöntemlerin manyetik bağlaşımdaki bobin karakteristiklerinin çıkarımında kullanılabileceğini göstermektedir. 

Keywords

• Kablosuz güç transferi,manyetik bağlaşım,bobin

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