•Develop an LRC for microgrid with CPL to keep voltage at a predefined point.•Present robustness of the LRC against parametric uncertainties.•Illustrate LRC robustness against parametric and ...frequency uncertainties, and AWGN.•Compare PID and LRC for microgrid with nonlinearity, variation, and noise.
In microgrid applications, stability issues have been raised into a matter of concern due to the continually increasing modern electronic loads and inverter-based power electronic loads. In this paper, adopting storage system based load side compensation technique, a Lyapunov redesign controller is proposed to considerably improve the microgrid stability in the presence of constant power loads. Besides the controller design, the robustness analysis of the proposed Lyapunov redesign controller against parameter uncertainties is depicted. After that, the proposed Lyapunov redesign controller robustness against parametric uncertainties, frequency variations, and additive white Gaussian noise (AWGN) is presented. Later, performance of the PID and Lyapunov redesign controller is compared in the case of nonlinearity, parameter uncertainties, and noise rejection to justify the selection of the Lyapunov redesign controller over the PID controller. Besides reckoning the necessary calculations, all of the results are verified in MATLAB/Simulink with the appreciable aftermath.
The network requirements of control systems in industrial applications increase day by day. The Internet based control system and various fieldbus systems have been designed in order to meet these ...requirements. This paper describes an Internet based control system with wireless fieldbus communication designed for distributed processes. The system was implemented as an experimental setup in a laboratory. In industrial facilities, the process control layer and the distance connection of the distributed control devices in the lowest levels of the industrial production environment are provided with fieldbus networks. In this paper, the Internet based control system that will be able to meet the system requirements with a new-generation communication structure, which is called wired/wireless hybrid system, has been designed on field level and carried out to cover all sectors of distributed automation, from process control, to distributed input/output (I/O). The system has been accomplished by hardware structure with a programmable logic controller (PLC), a communication processor (CP) module, two industrial wireless modules and a distributed I/O module, Motor Protection Package (MPP) and software structure with WinCC flexible program used for the screen of Scada (Supervisory Control And Data Acquisition), SIMATIC MANAGER package program (aSTEP7a) used for the hardware and network configuration and also for downloading control program to PLC.
Bu çalışmada generatörlerin paralel bağlanması şartlarından olan frekans ve faz açısının eşitlenmesi mikrodenetleyici ile gerçekleştirilmiştir. Yapılan çalışma, öncelikle frekans eşitliğini ...sağlamakta daha sonra ise faz açılarını eşitlemektedir. Şebeke ve generatöre ait gerilim bilgileri AA/AA sinyal algılama devresi tarafından uygun seviyelere getirilmekte ve sıfır geçiş anahtar devresi tarafından kare dalgaya dönüştürülmektedir. Kare dalgaya dönüştürülen bu sinyaller, PIC16F877 mikrodenetleyicisi için C programlama dilinde hazırlanan program tarafından, generatör sinyali referans sinyale eşleninceye kadar anahtarın iletim-kesim süreleri değiştirilmekte böylece DA motorun ve generatörün hızı ayarlanmaktadır. Şebeke ve generatör sinyalleri eşit olduğu anda frekans eşitliği sağlanmış olmaktadır. Frekanslar eşit olduktan sonra ise, aralarındaki açısal farkın sıfıra düşme anına kadar düşürücü kıyıcının iletim-kesim oranı ayarlanarak faz açıları eşitliği sağlanmaktadır.
The study presents a combined protection approach for induction motors (IMs). To achieve this, the current, voltage, speed and temperature values of the IM were measured with sensors and processed ...automatically with the developed software in C. The processes were then inserted into a microcontroller. The experimental results have shown that the IM was protected against the possible problems encountered in online operation. The approach presented in this work provides flexibility, accuracy and reliability for smooth protection with the help of the combined protection approach. Moreover, the protection system can easily be applied to larger motors after small modifications in the software developed. It is also expected that the proposed system would provide faster and low cost protection.
In this paper, a new algorithm has been introduced to regulate the DC capacitor voltage in single phase shunt active power filters to supply converter losses over the grid. In the system, the DC ...busbar voltage cannot be kept stable due to converter losses. The variation in DC busbar voltage decreases the power supplied by an active power filter. Conventionally, the voltage of a DC capacitor is regulated with a PI controller to overcome this problem. In this study, a new algorithm has been introduced to compensate for converter losses in the grid. According to this
algorithm, converter losses are calculated by comparing the real average active power and the reference average active power of the converter at the fundamental frequency. The power losses calculated have been added to average active power of the load and then the power losses consumed by converter have been supplied from the grid. The executed simulation results demonstrate the simplicity, effectiveness and low cost of the new algorithm.
Development of a real time energy monitoring platform Bayindir, Ramazan; Irmak, Erdal; Colak, İlhami ...
International journal of electrical power & energy systems,
2011, 2011-1-00, 20110101, Letnik:
33, Številka:
1
Journal Article
Recenzirano
This study introduces development of a user-friendly and quite effectual energy monitoring system which has been installed in Electrical Education Department of Gazi University in Turkey and in use ...since November 2007. The system developed monitors data in real time using a powerful energy analyzer which is capable of measuring many parameters of energy consumed in the building. The real time data measured by the power analyzer are transferred to a host computer via RS485 serial communication protocol and then collected in a database continuously. Thus, parameters of energy measured are successfully followed, archived, and presented as graphical forms.
The monitoring system presented in the study integrates to quite visual and quite user friendly interface with powerful and flexible hardware. Therefore, several functions can be performed easily and safely by simple actions. On the other hand, the system presented in our paper is developed in a university, so it can be used by students to learn energy systems and parameters.
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