The determination of photovoltaic (PV) model parameters has essential theoretical and practical significance for the performance evaluation, power monitoring, and power generation efficiency calculation of PV systems....
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The determination of photovoltaic (PV) model parameters has essential theoretical and practical significance for the performance evaluation, power monitoring, and power generation efficiency calculation of PV systems. In this paper, a multi-strategy gaining-sharing knowledge-based algorithm (MSGSK) is developed to determine these parameters. In our previous work, it has been demonstrated that gaining-sharing knowledge-based algorithm (GSK) is well suited for solving the concerned problem. To enhance its performance, a parameter adjustment strategy is developed to adjust the knowledge rate and knowledge ratio of GSK. Besides, a backtracking differential mutation strategy by combining the mutation scheme of differential evolution and the updating scheme of backtracking search optimization algorithm is developed to enrich the population diversity. Furthermore, a strategy selection mechanism is introduced to integrate the former two strategies to balance exploration and exploitation in different stages of the evolutionary process. The suggested MSGSK algorithm is applied to five PV cases (SDM, DDM, Photowatt-PW201, STM6-40/36, and STP6-120/36). From the experimental data, it can be observed that MSGSK extracts the PV model parameters more precisely than the basic GSK. Furthermore, it exhibits faster convergence speed and higher accuracy compared to other advanced algorithms found in the literature.
This article suggests an Enhanced gaining-sharing knowledge-based algorithm (eGSK) to resolve unrestricted optimization minimization problems over a continuous space. This algorithm is based on the idea that people le...
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This article suggests an Enhanced gaining-sharing knowledge-based algorithm (eGSK) to resolve unrestricted optimization minimization problems over a continuous space. This algorithm is based on the idea that people learn and share knowledge throughout their lives. The modification is fundamentally inspired by the principles of Adjust Selection Criteria, Modify Parameters Setup, and Escaping from Local Minimum Solutions, respectively. We conducted comparisons and statistical tests with the gaining-sharing knowledge-based algorithm (GSK) and other algorithms to verify and analyze the performance of the eGSK algorithm. We also performed numerical experiments on 29 test problem sets in 10, 30, 50, and 100 dimensions from the Congress on Evolutionary Computation (CEC) 2017 benchmark. The results were compared with three GSK variant algorithms, seven state-of-the-art algorithms, and GSK alongside components of the eGSK algorithm. According to test results, the eGSK algorithm performs exceptionally well at solving optimization problems with 30, 50, and 100 dimensions and is competitive in 10 dimensions. This means the proposed eGSK algorithm outperforms its competitors and achieves more competitive results, especially with high dimensions.
Fault section location (FSL) plays a critical role in shortening blackout time and restoring power supply for distribution networks. This paper converts the FSL task into a binary optimization problem using the feeder...
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Fault section location (FSL) plays a critical role in shortening blackout time and restoring power supply for distribution networks. This paper converts the FSL task into a binary optimization problem using the feeder terminal unit (FTU) information. The discrepancy between the reported overcurrent alarms and the expected overcurrent states of the FTUs is adopted as the objective function. It is a typical 0-1 combinatorial optimization problem with many local optima. An improved binary gaining-sharing knowledge-based algorithm (IBGSK) with mutation is proposed to effectively solve this challenging binary optimization problem. Since the original GSK cannot be applied in binary search space directly, and it is easy to get stuck in local optima, IBGSK encodes the individuals as binary vectors instead of real vectors. Moreover, an improved junior gaining and sharing phase and an improved senior gaining and sharing phase are designed to update individuals directly in binary search space. Furthermore, a binary mutation operator is presented and integrated into IBGSK to enhance its global search ability. The proposed algorithm is applied to two test systems, i.e. the IEEE 33-bus distribution network and the USA PG&E 69-bus distribution network. Simulation results indicate that IBGSK outperforms the other 12 advanced algorithms and the original GSK in solution quality, robustness, convergence speed, and statistics. It equilibrates the global search ability and the local search ability effectively. It can diagnose different fault scenarios with 100% and 99% success rates for these two test systems, respectively. Besides, the effect of mutation probability on IBGSK is also investigated, and the result suggests a moderate value. Overall, simulation results demonstrate that IBGSK shows highly promising potential for the FSL problem of distribution networks.
For the solar photovoltaic (PV) system to operate efficiently, it is necessary to effectively establish an equivalent model of PV cell and extract the relevant unknown model parameters accurately. This paper introduce...
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For the solar photovoltaic (PV) system to operate efficiently, it is necessary to effectively establish an equivalent model of PV cell and extract the relevant unknown model parameters accurately. This paper introduces a new metaheuristic algorithm, i.e., gaining-sharingknowledgebasedalgorithm (GSK) to solve the solar PV model parameter extraction problem. This algorithm simulates the process of knowledge acquisition and sharing in the human life cycle and is with strong competitiveness in solving optimization problems. It includes two significant phases. The first phase is the beginner-intermediate or junior acquisition and sharing stage, and the second phase is the intermediate-expert or senior acquisition and sharing stage. In order to verify the effectiveness of GSK, it is applied to five PV models including the single diode model, double diode model, and three PV modules. The influence of population size on the algorithm performance is empirically investigated. Besides, it is further compared with some other excellent metaheuristic algorithms including basic algorithms and advanced algorithms. Among the five PV models, the root mean square error values between the measured data and the calculated data of GSK are 9.8602E-04 +/- 2.18E-17, 9.8280E-04 +/- 8.72E-07, 2.4251E-03 +/- 1.04E-09, 1.7298E-03 +/- 6.25E-18, and 1.6601E-02 +/- 1.44E-16, respectively. The results show that GSK has overall better robustness, convergence, and accuracy. (C) 2021 The Authors. Published by Elsevier Ltd.
Economic dispatch (ED) of thermal power units is significant for optimal generation operation efficiency of power systems. It is a typical nonconvex and nonlinear optimization problem with many local extrema when cons...
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Economic dispatch (ED) of thermal power units is significant for optimal generation operation efficiency of power systems. It is a typical nonconvex and nonlinear optimization problem with many local extrema when considering the valve-point effects, especially for large-scale systems. Considering that differential evolution (DE) is efficient in locating global optimal region, while gain-sharingknowledge-basedalgorithm (GSK) is effective in refining local solutions, this study presents a new hybrid method, namely GSK-DE, to integrate the advantages of both algorithms for solving large-scale ED problems. We design a dual-population evolution framework in which the population is randomly divided into two equal subpopulations in each iteration. One subpopulation performs GSK, while the other executes DE. Then, the updated individuals of these two subpopulations are combined to generate a new population. In such a manner, the exploration and the exploitation are harmonized well to improve the searching efficiency. The proposed GSK-DE is applied to six ED cases, including 15, 38, 40, 110, 120, and 330 units. Simulation results demonstrate that GSK-DE gives full play to the superiorities of GSK and DE effectively. It possesses a quicker global convergence rate to obtain higher quality dispatch schemes with greater robustness. Moreover, the effect of population size is also examined.
Commercial airline companies are continuously seeking to implement strategies for minimizing costs of fuel for their flight routes as acquiring jet fuel represents a significant part of operating and managing expenses...
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Commercial airline companies are continuously seeking to implement strategies for minimizing costs of fuel for their flight routes as acquiring jet fuel represents a significant part of operating and managing expenses for airline activities.A nonlinear mixed binary mathematical programming model for the airline fuel task is presented to minimize the total cost of refueling in an entire flight route *** model is enhanced to include possible discounts in fuel prices,which are performed by adding dummy variables and some restrictive constraints,or by fitting a suitable distribution function that relates prices to purchased *** obtained fuel plan explains exactly the amounts of fuel in gallons to be purchased from each airport considering tankering strategy while minimizing the pertinent cost of the whole flight *** relation between the amount of extra burnt fuel taken through tinkering strategy and the total flight time is also considered.A case study is introduced for a certain flight rotation in domestic US air transport *** mathematical model including stepped discounted fuel prices is *** problem has a stochastic nature as the total flight time is a random variable,the stochastic nature of the problem is realistic and more appropriate than the deterministic *** stochastic style of the problem is simulated by introducing a suitable probability distribution for the flight time duration and generating enough number of runs to mimic the probabilistic real *** similar real application problems are modelled as nonlinear mixed binary ones that are difficult to handle by exact ***,metaheuristic approaches are widely used in treating such different optimization *** this paper,a gainingsharingknowledge-based procedure is used to handle the mathematical *** algorithm basically based on the process of gaining and sharingknowledge throughout the human *** generated simulation runs of
The effectiveness of meta-heuristics has recently been well demonstrated. However, there will be a need for reliable algorithms that can handle problems in the real world. The multiobjective nature-inspired meta-heuri...
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The effectiveness of meta-heuristics has recently been well demonstrated. However, there will be a need for reliable algorithms that can handle problems in the real world. The multiobjective nature-inspired meta-heuristic knowledge-based (NMHK) algorithm is an advanced version of the gaining-sharingknowledge optimization (GSK) algorithm, which is available in the literature. NMHK is designed specifically for tackling multiobjective optimization problems (MOPs). knowledge-sharingalgorithms are essential for easing the transfer of knowledge and expertise between people and groups. It is possible to significantly improve organizational learning, problem-solving, and decision-making by utilizing the collective knowledge and abilities of individuals. The NMHK algorithm, which is described in this paper, intends to improve the process of obtaining and spreading of knowledge. Moreover, the experimental results highlight the proposed NMHK algorithm's overall speedy performance, particularly when applied to realistic optimization problems.
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