77 research outputs found
Power Loss Minimization by Optimal Placement of Distributed Generation Considering the Distribution Network Configuration Based on Artificial Ecosystem Optimization
Power loss in the Distribution System (DS)
is often higher than that of other parts of the power
system because of its low voltage level. Therefore,
reducing losses is always an important task in de-
sign and operation of the DS. This paper aims to
apply a new approach based on Artificial Ecosystem
Optimization (AEO) for the Distributed Generation
Placement (DGP) and combination of DGP and net-
work REConfiguration (DGP-REC) problems to reduce
power loss of the DS to satisfy the technical constraints
including power balance, radial topology, voltage and
current bounds, and DG capacity limit. The AEO is
a recent algorithm that has no special control parame-
ters, inspired from the behaviours of living organisms
in the ecosystem including production, consumption,
and decomposition. The efficiency of the AEO is eval-
uated on two test systems including the 33-node and
119-node systems. The numerical results validated on
the 33-node and 119-node systems show that DGP-REC
is a more effective solution for reducing power loss com-
pared to the DGP solution. In addition, evaluation re-
sults on small and large systems also indicate that AEO
is an effective approach for the DGP and DGP-REC
problems
Optimal solutions for fixed head short-term hydrothermal system scheduling problem
In this paper, optimal short-term hydrothermal operation (STHTO) problem is determined by a proposed high-performance particle swarm optimization (HPPSO). Control variables of the problem are regarded as an optimal solution including reservoir volumes of hydropower plants (HdPs) and power generation of thermal power plants (ThPs) with respect to scheduled time periods. This problem focuses on reduction of electric power generation cost (EPGC) of ThPs and exact satisfactory of all constraints of HdPs, ThPs and power system. The proposed method is compared to earlier methods and other implemented methods such as particle swarm optimization (PSO), constriction factor (CF) and inertia weight factor (IWF)-based PSO (FCIW-PSO), two time-varying acceleration coefficient (TTVACs)-based PSO (TVAC-PSO), salp swarm algorithm (SSA), and Harris hawk algorithm (HHA). By comparing EPGC from 100 trial runs, speed of search and simulation time, the suggested HPPSO method sees it is more robust than other ones. Thus, HPPSO is recommended for applying to the considered and other problems in power systems
Modified moth swarm algorithm for optimal economic load dispatch problem
In this study, optimal economic load dispatch problem (OELD) is resolved by a novel improved algorithm. The proposed modified moth swarm algorithm (MMSA), is developed by proposing two modifications on the classical moth swarm algorithm (MSA). The first modification applies an effective formula to replace an ineffective formula of the mutation technique. The second modification is to cancel the crossover technique. For proving the efficient improvements of the proposed method, different systems with discontinuous objective functions as well as complicated constraints are used. Experiment results on the investigated cases show that the proposed method can get less cost and achieve stable search ability than MSA. As compared to other previous methods, MMSA can archive equal or better results. From this view, it can give a conclusion that MMSA method can be valued as a useful method for OELD problem
Determining optimal location and size of capacitors in radial distribution networks using moth swarm algorithm
In this study, the problem of optimal capacitor location and size determination (OCLSD) in radial distribution networks for reducing losses is unraveled by moth swarm algorithm (MSA). MSA is one of the most powerful meta-heuristic algorithm that is taken from the inspiration of the food source finding behavior of moths. Four study cases of installing different numbers of capacitors in the 15-bus radial distribution test system including two, three, four and five capacitors areemployed to run the applied MSA for an investigation of behavior and assessment of performances. Power loss and the improvement of voltage profile obtained by MSA are compared with those fromother methods. As a result, it can be concluded that MSA can give a good truthful and effective solution method for OCLSD problem
Active fault-tolerance of the unmanned aerial vehicle automatic control systems
This paper presents an introductory overview of principles of the three-layer hierarchy of active fault-tolerance, providing, determination of the fault type with as many details as enough to get recoverable fault reason and failure toleration by flexible redundancy using; the conception of active fault-tolerant control in abnormal modes is described. Developed models and methods of a systematic approach to fault tolerance in the direction of the effective use of the signal, parametric and structural redundancies and selection of parrying tools. Performed experimental researches of the unmanned aerial vehicle (UAV) automatic control systems (ACS)
The application of split step fourier migration to interpreting GPR data in Vietnam
Migration methods play an essential role in processing ground penetrating radar data. For estimating electromagnetic propagation velocity distribution, the finite - difference migration is used because of its reliable performance with high noise conditions. To optimize this migration algorithm, we propose using energy diagram as a criterion of looking for the correct velocity. If the velocity varies laterally and vertically, split step Fourier migration is used for creating a true image of subsurface structures. We applied these steps to real data in Vietnam. The results verified on field data show that migrated images with calculated velocity from energy diagram have the best quality
ĐA DẠNG THÀNH PHẦN LOÀI CÁ RẠN SAN HÔ Ở VỊNH XUÂN ĐÀI TỈNH PHÚ YÊN
We identified 65 reef fish species belonging to 48 genera, 27 families, 15 orders, and 2 classes (Chondrichthyes and Osteichthyes) at Xuan Dai Gulf, Song Cau town, Phu Yen province. Of these, there are 30 species with high conservation value at different rankings; 26 species with recreational value and used in ornamental fish farming, scuba diving, and recreational fishing; 3 reared species and 4 species likely to be reared; 15 species probably harmful to humans by injuring with fin spines and tail fins.Đã xác định được 65 loài cá rạn san hô thuộc 48 giống, 27 họ, 15 bộ của 2 lớp (cá Sụn – Chondrichthyes và cá xương – Osteichthyes) ở vịnh Xuân Đài, thị xã Sông Cầu, tỉnh Phú Yên. Trong số này, ghi nhận 30 loài có giá trị bảo tồn theo các thứ hạng khác nhau; 26 loài có giá trị giải trí, dùng trong nuôi làm cảnh, lặn ngắm cá và sử dụng trong câu cá thư giãn; 3 loài nuôi và 4 loài có khả năng gây nuôi; 15 loài có thể gây hại cho con người thông qua sát thương bằng gai vây và bằng vây đuôi
Researching migration methods, entropy and energy diagram to process ground penetrating radar data
Electromagnetic wave velocity is the most important parameter in processing ground penetrating radar data. Migration algorithm which heavily depends on wave velocity is used to concentrate scattered signals back to their correct locations. Depending wave velocity in urban area is not easy task by using traditional methods (i.e., common midpoint). We suggest using entropy and energy diagram as standard for achieving suitable velocity estimation. The results of one numerical model and areal data indicate that migrated section using accurate velocity has minimum entropy or maximum energy. From the interpretation, size and depth of anomalies are reliably identified
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