Loss and Cost Minimization with Enhancement of Voltage Profile of Distribution Systems Using a Modified Differential Evolution Technique

This paper addresses the problem of optimizing the voltage profile of radially-operated distribution systems by acting on the active and reactive powers provided by distributed energy resources (DERs). A novel voltage optimization procedure is proposed by adopting a decentralized control strategy. To this aim, a centralized voltage optimization problem (VOP), minimizing the distance of all the nodal voltages from their reference values, is firstly formulated as a strictly-convex quadratic program. Then, the centralized VOP is rewritten by partitioning the network into voltage control zones (VCZs) with pilot nodes. To overcome the lack of strictly convexity determined by the reduction to the pilot nodes, the dual centralized VOP working on the augmented Lagrangian function is reformulated and iteratively solved by the method of multipliers. Finally, a fully-distributed VOP solution is obtained by applying a distributed algorithm based on the auxiliary problem principle, which allows for solving in each VCZ a quadratic programming problem of small dimension and to drive the VCZ solutions toward the overall optimum by an iterative coordination process that requires to exchange among the VCZs only scalar values. The effectiveness and feasibility of the proposed method have been demonstrated via numerical tests on the IEEE 123-bus system.

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Generation of Alternative Battery Allocation Proposals in Distribution Systems by the Optimization of Different Economic Metrics within a Mathematical Model

Energies ◽

10.3390/en14061726 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1726

Author(s):

Norberto Martinez ◽

Alejandra Tabares ◽

John F. Franco

Keyword(s):

Mathematical Model ◽

Distribution Systems ◽

Net Present Value ◽

Test System ◽

Peak Time ◽

Voltage Profile ◽

Peak Reduction ◽

Stochastic Variation ◽

Peak Shaving ◽

Technical Operation

Battery systems bring technical and economic advantages to electrical distribution systems (EDSs), as they conveniently store the surplus of cheap renewable generation for use at a more convenient time and contribute to peak shaving. Due to the high cost of batteries, technical and economic studies are needed to evaluate their correct allocation within the EDS. To contribute to this analysis, this paper proposes a stochastic mathematical model for the optimal battery allocation (OBA), which can be guided by the optimization of two different economic metrics: net present value (NPV) and internal rate of return (IRR). The effects of the OBA in the EDS are evaluated considering the stochastic variation of photovoltaic generation and load. Tests with the 33-node IEEE test system indicate that OBA results in voltage profile improvement (~1% at peak time), peak reduction (31.17%), increased photovoltaic hosting capacity (18.8%), and cost reduction (3.06%). Furthermore, it was found that the IRR metric leads to a different solution compared to the traditional NPV optimization due to its inherent consideration of the relation between cash flow and investment. Thus, both NPV and IRR-based allocation alternatives can be used by the decision maker to improve economic and technical operation of the EDS.

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A new meta-heuristic pathfinder algorithm for solving optimal allocation of solar photovoltaic system in multi-lateral distribution system for improving resilience

SN Applied Sciences ◽

10.1007/s42452-020-04044-8 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Varaprasad Janamala

Keyword(s):

Distribution System ◽

Distribution Systems ◽

Voltage Stability ◽

Optimal Allocation ◽

Photovoltaic System ◽

Solar Photovoltaic ◽

Voltage Profile ◽

Pv System ◽

Solar Photovoltaic System ◽

The Impact

AbstractA new meta-heuristic Pathfinder Algorithm (PFA) is adopted in this paper for optimal allocation and simultaneous integration of a solar photovoltaic system among multi-laterals, called interline-photovoltaic (I-PV) system. At first, the performance of PFA is evaluated by solving the optimal allocation of distribution generation problem in IEEE 33- and 69-bus systems for loss minimization. The obtained results show that the performance of proposed PFA is superior to PSO, TLBO, CSA, and GOA and other approaches cited in literature. The comparison of different performance measures of 50 independent trail runs predominantly shows the effectiveness of PFA and its efficiency for global optima. Subsequently, PFA is implemented for determining the optimal I-PV configuration considering the resilience without compromising the various operational and radiality constraints. Different case studies are simulated and the impact of the I-PV system is analyzed in terms of voltage profile and voltage stability. The proposed optimal I-PV configuration resulted in loss reduction of 77.87% and 98.33% in IEEE 33- and 69-bus systems, respectively. Further, the reduced average voltage deviation index and increased voltage stability index result in an improved voltage profile and enhanced voltage stability margin in radial distribution systems and its suitability for practical applications.

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Optimization of Real Power Loss and Voltage Stability Index for Distribution Systems with Distributed Generation

International Journal of Engineering Research in Africa ◽

10.4028/www.scientific.net/jera.33.100 ◽

2017 ◽

Vol 33 ◽

pp. 100-114 ◽

Cited By ~ 2

Author(s):

Mostafa Elshahed ◽

Mahmoud Dawod ◽

Zeinab H. Osman

Keyword(s):

Genetic Algorithm ◽

Distributed Generation ◽

Distribution Systems ◽

Voltage Stability ◽

Reactive Power ◽

Optimization Problems ◽

Stability Index ◽

Mixed Integer ◽

Voltage Profile ◽

Voltage Stability Index

Integrating Distributed Generation (DG) units into distribution systems can have an impact on the voltage profile, power flow, power losses, and voltage stability. In this paper, a new methodology for DG location and sizing are developed to minimize system losses and maximize voltage stability index (VSI). A proper allocation of DG has to be determined using the fuzzy ranking method to verify best compromised solutions and achieve maximum benefits. Synchronous machines are utilized and its power factor is optimally determined via genetic optimization to inject reactive power to decrease system losses and improve voltage profile and VSI. The Augmented Lagrangian Genetic Algorithm with nonlinear mixed-integer variables and Non-dominated Sorting Genetic Algorithm have been implemented to solve both single/multi-objective function optimization problems. For proposed methodology effectiveness verification, it is tested on 33-bus and 69-bus radial distribution systems then compared with previous works.

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Optimal Harmonic Mitigation in Distribution Systems with Inverter Based Distributed Generation

Applied Sciences ◽

10.3390/app11020774 ◽

2021 ◽

Vol 11 (2) ◽

pp. 774 ◽

Cited By ~ 3

Author(s):

Ahmed S. Abbas ◽

Ragab A. El-Sehiemy ◽

Adel Abou El-Ela ◽

Eman Salah Ali ◽

Karar Mahmoud ◽

...

Keyword(s):

Power Quality ◽

Distributed Generation ◽

Distribution System ◽

Distribution Systems ◽

Renewable Energy Sources ◽

Harmonic Distortion ◽

Planning Problem ◽

Voltage Profile ◽

Harmonic Mitigation ◽

The Impact

In recent years, with the widespread use of non-linear loads power electronic devices associated with the penetration of various renewable energy sources, the distribution system is highly affected by harmonic distortion caused by these sources. Moreover, the inverter-based distributed generation units (DGs) (e.g., photovoltaic (PV) and wind turbine) that are integrated into the distribution systems, are considered as significant harmonic sources of severe harmful effects on the system power quality. To solve these issues, this paper proposes a harmonic mitigation method for improving the power quality problems in distribution systems. Specifically, the proposed optimal planning of the single tuned harmonic filters (STFs) in the presence of inverter-based DGs is developed by the recent Water Cycle Algorithm (WCA). The objectives of this planning problem aim to minimize the total harmonic distortion (THD), power loss, filter investment cost, and improvement of voltage profile considering different constraints to meet the IEEE 519 standard. Further, the impact of the inverter-based DGs on the system harmonics is studied. Two cases are considered to find the effect of the DGs harmonic spectrum on the system distortion and filter planning. The proposed method is tested on the IEEE 69-bus distribution system. The effectiveness of the proposed planning model is demonstrated where significant reductions in the harmonic distortion are accomplished.

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Reactive Power Compensation of Oilfield Distribution Systems Based on Tabu Search Algorithm

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.397-400.1113 ◽

2013 ◽

Vol 397-400 ◽

pp. 1113-1116

Author(s):

Xiao Meng Wu ◽

Wang Hao Fei ◽

Xiao Mei Xiang ◽

Wen Juan Wang

Keyword(s):

Power Loss ◽

Distribution Systems ◽

Reactive Power ◽

Search Algorithm ◽

Global Optimum ◽

Reactive Power Compensation ◽

Active Power ◽

Voltage Profile ◽

Voltage Range ◽

Shunt Capacitors

In order to solve the problem in reactive power compensation of oilfield distribution systems at present, a Taboo search algorithm is proposed in this paper, by which the optimal location and size of shunt capacitors on distribution systems are determined. Then the voltage profile is improved and the active power loss is reduced. In this paper, Voltage qualified is used as objective function to search an initial solution that meets the voltage constraints so that it is feasible in practicable voltage range; then the global optimum solution can be got when taking the reduced maximum of active power loss as objective unction. The examples show that the improved algorithm is feasible and effective.

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