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Rüzgâr değişken yapılı bir enerji kaynağıdır. Şebekeye bağlı rüzgâr türbin sistemlerinde rüzgârın değişken yapısı şebekeyi olumsuz etkilemektedir. Burada önemli olan şebeke entegrasyon etkilerinin standartlar dahilinde olmasını sağlayabilmektir. Bu sayede şebekede ciddi problemlerin oluşması engellenir. Bu nedenle şebeke entegrasyon etkilerinin araştırılması ve bu etkilerin azaltılmasına yönelik çalışmaların önceden yapılması oldukça önemlidir. Ancak literatürde şebeke entegrasyon etkilerinin incelenmesi ve bu etkilerin azaltılmasına yönelik yapılan sınırlı sayıda çalışma bulunmaktadır. Bu amaçla çalışmada, şebekeye bağlı 3 MVA’lık kalıcı mıknatıslı senkron generatöre (KMSG) sahip bir rüzgâr türbin sistemi, PSCAD/EMTDC’de modellenmiştir. Oluşturulan model yardımıyla rüzgârın değişken yapısı, rüzgâr enerji santrallerinin şebekeye entegrasyonu incelenmiş ve farklı yük koşulları altında rüzgâr santralinden şebekeye aktarılan güç miktarları sunulmuştur. Aynı zamanda rüzgârın kesikli ve değişken yapısının şebeke üzerinde oluşturabileceği olumsuz etkiler analiz edilerek bu etkilerin azaltılması amacıyla, DC hat üzerinde invertörün kontrollü çalışmasını sağlayan gerilim regülasyon işlemi gerçekleştirilmiştir., Wind is a variable struct energy source. The variable nature of the wind in grid-connected wind turbine systems adversely affects the grid. The important thing here is to ensure that the grid integration effects are within the standards. In this way, serious problems in the grid are prevented. For this reason, it is very important to investigate the effects of grid integration and to carry out studies to reduce these effects in advance. However, there are limited studies in the literature to examine the effects of grid integration and to reduce these effects. For this purpose ın study, a wind turbine system with a 3 MVA permanent magnet synchronous generator (PMSG) connected to the grid is modeled in PSCAD/EMTDC. With the help of the created model, the variable nature of the wind, the integration of wind power plants into the grid are examined and the amount of power transferred from the wind farm to the grid under different load conditions is presented. In addition, the negative effects of the intermittent and variable nature of the wind on the network were analyzed and in order to reduce these effects, the voltage regulation process was carried out on the DC line, which ensures the controlled operation of the inverter.

In this paper, a DC-DC converter designed specifically for the case of an input voltage with flicker to generate a DC output without oscillations. The PI controller of the DC-DC converter is designed to be variable gain and adaptive to the input voltage signal. The designed system has been first tested in the Matlab/Simulink environment with the rectified form of the synthetic input voltage signals generated based on the test signals with flicker recommended in the IEC 61000-4-15 Flickermeter Standard and the output voltage is controlled. The output voltage obtained by the proposed system and the standard PI controlled system are compared for various input signals with flicker and it has been observed that significant reduction in the output oscillation is obtained. The proposed system also reduces the initial overshoot of the output voltage. The proposed input voltage adapted VGPI controller has also been tested by the rectified form of the actual power system voltage signals obtained from the transformer substations supplying electric arc furnaces causing serious levels of voltage flicker. It has been shown that the oscillations at the output voltage of the proposed DC-DC converter is significantly reduced.

This paper presents an active-reactive power control strategy for voltage source converters (VSCs) based on derivation of the direct and quadrature components of the VSC output current. The proposed method utilizes a multivariable proportional-integral controller and provides almost completely decoupled control capability of the active and reactive power with almost full disturbance rejection due to step changes in the power exchanged between the VSC and the grid. It also imposes fast transient response and zero steady-state error as compared to the conventional power control approaches. The applicability of the proposed power control strategy for providing the robust stability of the system against the uncertainties of the load parameters is also investigated. The superiority of the proposed control strategy over conventional approaches in the new condition of supplying the load is demonstrated. The theoretical aspects of the proposed multivariable-based power control strategy and the conventional approaches are reviewed and simulation results are presented in two separate sections. MATLAB/Simulink 2009a is used to simulate different scenarios of the simulation.

A state feedback control method for an interleaved boost power converter is designed, which, in turn, can achieve interleaved current sharing among parallel-connected converters. The state feedback control in the continuous time domain is derived using the pole placement technique and linear quadratic optimal method. The load estimator is designed by deriving a full-order state observer to ensure the robustness and optimality of the state feedback control and an observer-based controller (control law plus full-order state observer) is designed using the separation principle. The adopted control strategies achieve effective output voltage regulation, good dynamic stability, and reject disturbances. Extensive simulation is carried out and the results are illustrated.

The purpose of this paper is to design a good tracking controller for the generator automatic voltage regulator (AVR) system. It uses an iterative learning control (ILC) algorithm as a control rule and tries to keep voltage error as low as possible, while replying to set point changes as fast as possible. Two models of ILC are discussed: P-type learning and linear quadratic (LQ) optimal design. The results of designing by LQ optimal method are compared with a Ziegler--Nichols proportional-integral-derivative (PID) controller. The effects of changing different parameters are investigated and illustrated by simulation. In order to provide better robustness for the design, a PID-ILC parallel structure is designed and simulated under system parameter changes.

An observer controller for a buck converter is presented. A state feedback gain matrix is derived in order to achieve the stability of the converter and to ensure the robustness of the controller. A load estimator is designed to estimate the unmeasurable variables and to obtain the zero output voltage error. A pulse-width modulation scheme is adopted to obtain the output voltage regulation. In order to improve the transitory response and dynamic constancy of the converter, the controller parameters are designed based on the current mode control. The design is evaluated and verified using MATLAB/Simulink. An experimental set-up is done to evaluate the controller platform.

WOS: 000273608300006, Together with the improvement in current and voltage handling capacities of power electronic devices, different type controllers have been increasingly used for efficient shunt and series compensation. The most promising controllers based on power electronics are known as Flexible AC Transmission Systems (FACTS) devices. In this study, the effects of two of shunt FACTS devices, which are Thyristor Switched Capacitor (TSC) and Thyristor Switched Reactor (TSR)-based Static VAr Compensator (SVC) on load bus voltage are investigated. Six Pulse Generator and PI Controller are used to control firing angles of TSC and TSR-based SVC. These compensators are simulated by using Matlab/Simulink, Power Systems Toolbox. Analyzed the studied three phase power system consists of two buses, a static load and a long transmission line model. The simulation results show that PI controller can be easily applicable to these type compensators.