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A novel isolated 7-level (7L) multi-level inverter (MLI) topology for grid-connected medium and high voltage power applications is presented in this paper. The topology consists of two isolated transformers with different winding ratio and four switches connected to a single-phase grid. This topology provides a great advantage over conventional MLIs by reducing passive and active components to allowing a 7L output voltage. Moreover, model predictive control (MPC) method is implemented to 7L-MLI to generate gate signals of switches and ensure capacitor voltage balancing and grid connection. Performance of proposed topology has been confirmed by in-depth analysis under simulation and laboratory setup with existing studies. Experimental results of a 1.5 kW 220 V-rms prototype are presented to support the simulation results. The prototype shows that the harmonic results match the limits of the IEC 61000-3-2 standard and show a better performance for grid connection and capacitor voltage balancing than conventional ones.

In this study, implementation of incremental fuzzy control (IFC) method on field programmable gate array (FPGA) is investigated for gimbals and fins of missiles that include brushless direct current (BLDC) motors and its comparison with conventional proportional-integral (PI) control method are analyzed. BLDC motors are widely used in two important parts of guided missiles due to their high performance. Firstly, gimbals usually consist of seeker cameras, whose axis controls are provided by BLDC motors. These motors provide two axis seeker camera motions, so that the missiles can trace the target. Secondly, missiles can be guided to intended direction by BLDC motors that are used in the control system of fins. According to these important roles, controlling of BLDC motors is very important for defense industry. Therefore, performance of FPGA-based conventional PI and proposed IFC methods on BLDC motors are analyzed in detailed in terms of both simulation and experimental study. Simulation results are obtained by using MATLAB/Simulink program. Also, an FPGA-based test bench is used for experimental studies. Results obtained from simulation and experimental set up are compared and it is proved that the implementation of proposed IFC method improves the BLDC motor performance used in missiles compared to the conventional PI control method.

Robotik sistemler, endüstride çoğunlukla yüksek hassasiyet gerektiren işlerde kullanılmaktadır. Bu yüzden, robot manipülatörlerinin üzerinde yoğun çalışmalar yapılmaktadır. Bu çalışmada iki serbestlik derecesine sahip robot kolunun PD, Anfis ve melez anahtarlamalı PD-Anfis kontrol yöntemleri kullanılarak yörünge kontrolü gerçekleştirilmiş ve performans değerlendirilmesi yapılmıştır.Robot sistemlerinin kontrolü hakkında literatürde bulunan önceki çalışmalar incelenmiş, bu çalışmaların ilgili kısımları teze özel olarak uygulanmıştır. Tasarım yapabilmek için öncelikle robotun ileri kinematik, ters kinematik ve dinamik denklemleri çıkarılmıştır. Hesaplanan kinematik ve dinamik denklemler ile PD robot kontrolü gerçekleştirilmiş, daha sonra Matlab programında bulunan Anfis editörü ile farklı bir kontrolör yaklaşımı uygulanarak PD kontrolör ile Anfis kontrolör karşılaştırılmıştır. Daha sonra Anfis kontrolörün olumlu ve olumsuz yönleri kıyaslanmış ve olumsuz yönlerini yok etmek için farklı bir yaklaşım olarak melez anahtarlamalı PD-Anfis kontrolör yöntemi uygulanmış ve tüm kontrolör yöntemleri için kıyaslama yapılmıştır.Klasik PD kontrol yöntemi ile sistem sabitleri olan Kp ve Kv değerleri değişmez iken uygulanan yeni yaklaşım ile PD kontrolörün çıkışı Anfis ile eğitilip hata ve hatadaki değişim oranına göre çıkış değerinin ayarlanması sağlanmıştır. Bu sayede PD kontrolöre göre daha az hata oranına sahip ve referansı daha iyi takip edebilen çıkışlar elde edilmiştir. Robotic systems are mainly used for works requiring high precision in the industry. For this reason, intensive studies are conducted on robot manipulators. In this study, the orbital control of the robotic arm which has two freedom degrees is conducted by using the control methods of PD, Anfis and hybrid PD-Anfis and its performance evaluation is carried out.The former studies on the control of the robotic systems existing in the literature are examined and the related parts of these studies are carried out dedicatedly to the dissertation. To be able to design, firstly the forward kinematic, inverse kinematic and dynamic equations of the robot are created. The PD robot control is executed using the calculated kinematic and dynamic equations, then the PD controller and Anfis controller are compared according to a different controller approach with the Anfis editor of Matlab software. Thereafter, the positive and negative aspects of the Anfis controller are contrasted and hybrid PD-Anfis controller method is conducted as a different approach and all controller methods are compared to eliminate the negative aspects.While the system constants Kp and Kv values remain constant with the classic PD control method, the output of PD controller is trained with Anfis with the new method and the output value is adjusted according to the error and the change rate of the error. By this way, outputs which have less error rate and which are able to follow the reference better are obtained. 124