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Bu çalışmada gerçek bir ters sarkaç sistemi için yeni bir uyarlamalı kazançlı, bağımsız yüzeyli kayan kip denetim tekniği (UKKKD) önerilmektedir. Böylece modellenemeyen ve üst sınır değerleri belirli olmayan bozucu etkilere karşı dayanıklı bir denetim yapısı elde edilmektedir. Önerilen denetim yöntemi ile dayanıklılık özelliği en küçük kazanç değerlerinde dahi korunmakta ve böylece kayan kip denetimin temel problemi olan çatırtı etkisi de azaltılmaktadır. Çalışmada, ters sarkaç ve denetim sisteminin MATLAB/SIMULINK benzetim ile uygulama grafikleri karşılaştırmalı olarak verilmiş ve denetimin olumlu etkisi doğrulanmıştır.624432

One of the major issues is that the output power and power transfer efficiency are dependent on the coupling coefficient (k) between the magnetic couplers. Any deviations in optimal distance, misalignment between the couplers or un-modeled dynamics such as temperature dependent variation in components lead to a shift in system’s resonance frequency. Also, asymmetric frequency splitting phenomenon occurs decreasing the output power and the power transfer efficiency of the system. Non-metaheuristic optimization methods are not capable of distinguishing the global maximum power (GMP) transfer frequency under frequency splitting conditions. This study presents an adaptive wireless power transfer (WPT) system with a Cuckoo Search Algorithm (CSA) based frequency-tracking method. GMP transfer frequencies determined by experimental frequency scanning method. The method is implemented under asymmetric splitting conditions for the first time. The suitability of the algorithm is tested in an experimental WPT setup. In experimental studies, wireless power transfer was provided through flux pipe couplers with three sub-coils which exhibit higher coupling coefficient as compared to traditional flux pipe couplers with two sub-coils. Results show that the CSA based controller can accurately find the optimal operation frequency under various misalignment and distance between the couplers.

Kılıç, Fuat (Balikesir Author), One of the major challenges in inductive wireless power transfer (WPT) systems is that the optimal frequency of operation may shift predominantly due to coupling variation as a result of so-called frequency splitting phenomenon. When frequency splitting occurs, two additional resonance frequencies split from the coupler’s resonance frequency. Maximum power levels are observed at these split resonance frequencies; however, these frequencies are strongly-dependent on the coupling coefficient, hence the distance and alignment between the couplers. In addition to that, peak power values at these frequencies can be different from each other due to small impedance differences between the primary and secondary side resonant couplers, forming a local and a global maximum. Therefore, the WPT system should adaptively operate at the correct frequency for achieving maximum power transfer. In this paper, a metaheuristic Particle Swarm Optimization (PSO) based frequency tracking algorithm is proposed for use in WPT systems. The WPT system employs multi sub-coil flux pipe couplers, a full-bridge inverter which is driven by TMS320F28069 controller card and is suitable for high power charging applications. The control algorithm can accurately find the global maximum power point in case of frequency splitting with asymmetric peaks. The proposed frequency tracking algorithm operates only at the primary side based on measurement of the input power level. Therefore, no additional communication link is needed between the primary and the secondary side. Effectiveness of the proposed control method is validated by performing experiments under three different misalignment scenarios and compared to the traditional Perturb and Observe algorithm

Sis, Seyit Ahmet (Balikesir Author), Flux pipe couplers are compact coils used in wireless power transfer (WPT) applications. The first part of this paper investigates the effect number of sub-coils on the magnetic characteristics. Flux pipe couplers with more than two sub-coils exhibit higher coupling coefficient as compared to traditional flux pipe couplers with two sub-coils. Furthermore, multi sub-coil flux pipe couplers better distribute the magnetic flux inside the core, making them attractive in high power applications. The second part presents an experimental WPT system employing multi sub-coil flux pipe couplers with three sub-coils. More than 82% power transfer efficiency is observed when couplers are separated with 100 mm vertical gap. Lateral misalignments up to 200 mm are then applied, and meantime, the separation between sub-coils is varied for achieving maximum efficiency. A near-constant efficiency is obtained up to 150 mm misalignment. Therefore, this paper announces another potential use of flux pipe couplers realizing an adaptive WPT system.

KALE, MURAT/0000-0002-3814-9009; Karabacak, Murat/0000-0001-6468-8471 WOS: 000366770300017 This paper proposes a new robust adaptive controller for LCL filter based shunt active power filters in order to solve the control problems of high overshoot and large settling time in the DC link voltage. To this end, the second order sliding mode with the adaptive gain super-twisting control law and proportional-resonant controllers with active damping are used in the DC bus voltage control loop and d-q axis current control loops respectively. The control objectives are fourfold: (I) driving the DC bus voltage to a reference signal; (ii) forcing the d-q axis current errors to zero; (iii) assuring a satisfactory power factor correction and a high harmonic performance in relation to the AC source; and (iv) eliminating the chattering effect. In the closed loop control system, three phase grid currents, LCL capacitor currents and the DC link voltage are available for feedback. As a result, the proposed controller has the advantages of zero overshoot response and fast acting chattering-free behavior. Results of experimental studies prove that the proposed control system guarantees to track reference signals with a high harmonic performance despite external disturbance uncertainties. (C) 2015 Elsevier Ltd. All rights reserved. Sakarya University Scientific Research FoundationSakarya University; Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) Dr. Murat Karabacak would thank the Sakarya University Scientific Research Foundation and Dr. Murat Kale would thank the Scientific and Technological Research Council of Turkey (TUBITAK) respectively for the support of this study.

Ruzgârdan elektrik enerjisi uretmek icin kullanilan ruzgâr turbinlerinin en ilkel denetim yontemi, sabit hizli denetim yontemidir. Bu yontemle, turbin giris gucunun maksimum oranda sebekeye aktarilmasi mumkun degildir. Bu nedenle Maksimum Guc Izleme (MGI) semalari onerilmistir. MGI yapabilmek icin ruzgâr hizinin her farkli degerinde, pervane farkli bir hizla donmelidir. Bu durum MGI tabanli sistemlere Degisken Hizli Ruzgâr Turbini (DHRT) sistemleri denilmesine yol acmistir. DHRT sistemlerinde turbin giris gucu maksimum guce yakin oranlarda sebekeye aktarilabilmektedir. DHRT sistemlerinin MGI tabanli denetimi soz konusu oldugunda iki onemli islem one cikar. Bunlar MGI noktasinin anlik olarak saptanmasi ve izlenmesidir. Bu calismada kanat ucu hiz orani tabanli maksimum guc izleme semasi kullanilarak, Sabit Miknatisli Senkron Generatorlu (SMSG) bir DHRT sistemi ile ruzgârda bulunan guc degeri maksimum oranda arka arkaya bagli cevirici sistem uzerinden sebekeye aktarilmaktadir. Ayrica fiziksel bir ruzgâr turbini modellenmis ve benzetimi yapilmistir. Sonuclar zamanla degisen bir MGI noktasinin yuksek performansla izlendigini gostermektedir.