Majlesi Journal of Energy Management
Volume:7 Issue: 3, Sep 2018

In this work a direct torque control scheme based on neural super-twisting sliding mode (NSTSMC) algorithm and space vector modulation (SVM) of a doubly fed induction generator (DFIG) integrated in a wind energy conversion system is presented. The traditional DTC control with hysteresis controllers has significant torque and flux ripples at steady-state operation and also the switching frequency varies in a wide range. The proposed DTC control scheme based on NSTSMC algorithm reduces torque, flux and current ripples. Two different sliding surfaces such as torque and flux sliding surfaces are used to control them. The simulation results have been carried out using MATLAB/SIMULINK software. Simulation results show the effectiveness of the proposed DTC control scheme comparatively to the classical DTC one.

DG is a better alternative to meet power demand near the load centers than centralized power generation. Optimal placement and sizing of DGs plays a crucial role in improving the performance of distribution systems in terms of network loss reduction, voltage profile improvement, reliability of power supply and stability issues. In this paper, a new method is proposed to solve intelligent distribution network reconfiguration in the presence of DGs aiming to minimize active power loss and improve voltage profile. Meta-heuristic optimization algorithm based on training-learning (TLBO) is used to reconfigure distribution network. In order to investigate different operational conditions of distribution systems and efficiency of the proposed method, different scenarios of network reconfiguration are simulated and studied. In order to illustrate performance and effectiveness of the proposed method, IEEE-33 bus radial distribution network is simulated at three different levels. In the proposed scenarios, presence or absence of DGs in different buses and effect of capacity of these sources is studied and simulated.

This paper numerically evaluates the voltage drop, the current rating of the network, the voltage profile, the total active and reactive power losses, and the current rating of short circuits. The calculations of these parameters are performed at both sending and receiving ends of a practical feeder in an extensive network in Hamadan city in Iran, with more than 180 load points. Regarding the desired parameters, the best Substations is selected to supply the feeder. The numerical analyses are formulated in Microsoft Excel software. The numerical results highlight the fact that there is a good agreement between numerical outcomes and published data in which professional software is used. It is shown that the proposed numerical method can be utilized with excellent outcomes instead of studying power distribution networks using professional commercial software. The outcomes ensure that the numerical results are satisfactorily accurate, and the evaluation of the distribution network can be conducted in a short time. Besides, due to the compatibility of data, the results can be post-processed effortlessly in other software such as MATLAB. Consequently, compared to the conventional methods, the numerical proposed method is predominantly cost-effective in terms of evaluation of power distribution networks.

In this paper, a nonlinear model of a gas turbine system in a thermal power plant is studied. Due to the impact of the outlet temperature on the turbine speed performance and the multivariability of the system model, the design of the nonlinear multivariate controller has been considered. Comparison of the results with the PID industrial controller method shows the desired performance of the designed system.

Sustainable energy strategies generally involve both the use of sustainable energy sources and improvements in energy conservation. This energy generation technologies have been at the forefront due to concerns related to the environment, energy independence, and high fossil fuel costs. As an application of the Photovoltaic technology, building integrated photovoltaic (BIPV) systems have attracted increasing interest in the past decade, and have been shown as a feasible renewable power generation technology to help buildings partially meet their load. Conventional PV systems can not be applied to arched facades. During this research, flexible photovoltaic system (FPVS) supported elastic solar panels were designed, manufactured and evaluated on a Model layer of 1m2 and 56W. A flexible system was analyzed in real terms on a flat, cylindrical and hemispherical surface. Warm and dry environmental data were recognized and communicated on-line into LabVIEW software. The smallest quantity of fill factor (FF) relates to a flat surface and also the systems once installed on the silo and biogas surfaces, have a fill factor of 0.88 and 0.84, respectively. The maximum power related to system deployment on the cylinder surface is 59.87W, whereas the minimum power of the system, when deployed on the flat surface, is 57.84W. The most effective power in the RSM deployment on the hemispherical surface is equal to 61.14W. The minimum power is 56.6W when deployed on the flat surface. The system's performance under standard conditions on the cylinder and dome surfaces are measured at 7.45%. The quantity of laboratory power output was related to the hemispherical, cylindrical, and flat surfaces, and its value is 46.7W, 55.1W, and 57.5W respectively. The economic analysis of COMFAR III was ranked based on the hemispherical, cylindrical and flat surfaces, respectively.