Distribution Network Losses Research Articles

Optimisasi Multi-objektif pada Rekonfigurasi Jaringan Distribusi Tenaga Listrik dengan Integrasi Pembangkit Terdistribusi Menggunakan Metode Sistem Kekebalan Buatan

This study proposes a multi-objective optimization for power distribution network reconfiguration by integrating distributed generators using an artificial immune system (AIS) method. The most effective and inexpensive technique in reducing power losses in distribution networks is optimizing the network reconfiguration. On the other hand, small to medium scale renewable energy power plant applications are growing rapidly. These power plants are operated on-grid to a distribution network, known as distributed generation (DG). The presence of DG in this distribution network poses new challenges in distribution network operations. In this study, the distribution network optimization was carried out using the AIS method. In optimization, the goal to be achieved is not only one objective but should be multiple objectives. Multi-objective optimization aims to reduce power losses, improve the voltage profile, and maintain a maintained network load balance. The AIS method has the advantage of fast convergence and avoids local minima. To test the superiority of the AIS method, the distribution network optimization with and without DG integration was carried out for the 33-bus and 71-bus models of the IEEE standard distribution networks. The results show that the AIS method can produce better system operating conditions than before the optimization. The parameters for the success of the optimization are minimal active power losses, suitable voltage profiles, and maintained load balance. This optimization has successfully increased the efficiency of the distribution network by an average of 0.61%.

Water Loss Management in Small Municipalities: The Situation in Tyrol

Water losses in water distribution networks (WDNs) are unavoidable. Water losses are evaluated based on performance indicators (PIs) and used for future recommendations for network operators to take measures against water losses. However, these evaluations primarily focus on large and medium sized WDN and do not deal with the challenges of small WDNs (e.g., technical, and financial limitations, missing data). Therefore, an appropriate water loss management is a major challenge for operators in the federal state of Tyrol (Austria) due to the high number of small WDNs, e.g., low income in combination with long network lengths. In this regard, this work specifies and discusses state funding in Austria to support network operators to reduce water losses. To assess the impacts on management strategies, 40 WDNs, supplying 200 to 16,000 inhabitants, are investigated in detail. As the comparison of different PIs shows, a volume related PI (e.g., water loss volume divided by total water demand) is recommend as the decision criterion for local authorities due to minimal efforts and its easy calculation. Moreover, public funding helps to significantly reduce water losses in individual systems, but countermeasures should be different for small and larger WDNs. For example, leakage detection campaigns and rehabilitation planning based on pipe age should be established in future for larger WDNs in Tyrol. In contrast, an online flow metering system to monitor system inflows is suggested for small WDNs. Based on measurement data, leakages and burst can be detected and repaired swiftly.

New analytical approach for simultaneous feeder reconfiguration and DG hosting allocation in radial distribution networks

This paper proposes an analytical approach for reconfiguration simultaneously with DG hosting (RSDG) to reduce losses in the radial distribution networks (RDNs). Previous researches have mainly utilized Artificial Intelligence (AI) techniques that need dramatic computational efforts and may lead to local-optima. Through an extensive circuit analysis new terms called “Diff and Pivot” are proposed based on analytical formulations. The diff value represents the difference between the maximum loss reduction caused by a DG placed at a bus and the previous bus. Pivot relates diff values at every two successive branches. An algorithm named Pivot for Simultaneous Reconfiguration and DG Hosting (PSRH) is developed. For verification, PSRH is applied to IEEE-33, IEEE-69, and practical 84-bus RDNs and results are compared to AI techniques. Deduced outcomes are very encouraging with fewer computational steps. Moreover, the compromised solution of PSRH is superior when considering the outages of DGs as PV modules at night.

Discussion on “A New Formulation of Distribution Network Reconfiguration for Reducing the Voltage Volatility Induced by Distributed Generation”

The authors of conscientiously contributed to formulate a network reconfiguration scheme to mitigate the impact of renewable (RE) based distributed generations (DG) on the voltage profile and network losses in a power distribution network. A novel voltage volatility index is outlined and proposed by the authors to analyze the impact of RE transient power output on bus voltage. Further, a new optimization algorithm based on Benders decomposition is presented for the regulation of bus voltage and reduction of system network losses through switching of the capacitor banks (CB) and optimized network reconfiguration.

ANALISIS RUGI DAYA DAN REKONSILIASI ENERGI JARINGAN DISTRIBUSI TEGANGAN MENENGAH 20 KV PADA PENYULANG NIJANG

This study aims to determine the loss / power loss in the nijang feeder through the energy reconciliation process, simulation of the ETAP 12.6 program, and manual calculations. The benefits of this research can be used as a basis for consideration of the improvement efforts that should be carried out to minimize power losses in the medium voltage distribution network of Nijang feeders. The method used is quantitative research method because it takes data from the measurement of the transaction point which is then compared with the results in the simulation program ETAP 12.6 and manual calculations. The results showed that the power loss (kWh) resulted from 3 processes showed that the energy reconciliation process resulted in a greater power loss, namely 10,657 kWh, the ETAP 12.6 simulation resulted in a power loss of 3049 kWh and in manual calculations it resulted in losses. power of 4199 kWh, from the results of the research it can be seen that in the simulation process ETAP 12.6 and manual calculations only calculate power losses due to technical causes, while the energy reconciliation process includes technical and non-technical causes. It is hoped that this research can support efforts to improve power losses / losses in the PT PLN (Persero) UP3 Sumbawa environment.

Optimal Siting and Sizing of Multiple Distributed Generation Units in Radial Distribution System Using Ant Lion Optimization Algorithm

The installation of distributed generation (DG) units with optimal capacities at optimal locations is becoming an essential issue in a distribution power network to reduce total power loss and to enhance voltage profile. In this paper, a recently included optimization technique called ant lion optimizer (ALO) has been presented for assessing the optimal size of multiple DG units in a balanced radial distribution system. An integrated methodology of loss sensitivity factor and voltage sensitivity factor is utilized for finding the optimal bus locations for the multiple DG unit installation. The optimal size of DG units at the identified bus locations are computed using ALO algorithm by minimizing the total real power loss of distribution network. The minimization of total real power loss will lead to considerable enhancement in voltage profile. The performance of the proposed algorithm has been evaluated against IEEE 33, 69 and 119 bus balanced radial distribution systems. Furthermore, to outline the superiority of proposed ALO algorithm, the attained results are related with the results of hybrid optimization techniques such as GA-PSO, ABC-CSO and ABC-BAT in terms of total real power reduction and voltage profile improvement.

Optimal Placement and Sizing of Reactive Power Sources in Active Distribution Networks: A Model Predictive Control Approach

Reactive power sources have the potential for active distribution network (ADN) loss reduction and voltage profile improvement. However, the effective operation of reactive power sources depends upon their proper placement and sizing. To address this issue, this paper presents an optimal reactive power source allocation strategy in ADN. The salient feature of this strategy is that, by incorporating the ADN control scheme into the allocation process, it achieves the optimal allocation in a dynamic context. Specifically, smart transformer is considered as a particular realization of reactive power source, and the allocation problem is formulated as linear programming, which aims to minimize the investment cost of smart transformers. Meanwhile, the ADN control scheme is designed via model predictive control (MPC), with objectives of voltage regulation and loss reduction. Subsequently, the MPC formulation is embedded into the allocation problem, thus forming an integrated optimization problem, which links the control domain with the planning domain. By using the generalized Benders decomposition, this integrated problem is decomposed into a master problem and a set of subproblems, which can be solved alternately and iteratively. Simulation results verify the effectiveness of the proposed strategy.

Operation optimization of AC/DC hybrid distribution network considering uncertainty

In order to solve a series of problems such as the increase of AC/DC hybrid distribution network loss caused by the uncertainty of wind and solar output. Based on the uncertainty theory, wind power plants and photovoltaic power generation are modeled, and a power flow calculation method for AC/DC distribution networks is proposed. Considering that when consuming fixed distributed generation, the minimum network loss is the objective function, and a particle swarm optimization-based AC/DC operation optimization method is proposed. Finally, the validity and feasibility of the proposed method are verified by simulation examples.

Multi Objective Grey Wolf Optimization for Optimal Allocation of Distributed Generators in Distribution Networks

The power loss in the radial distribution network is appreciable as compared to transmission network. To reduce the power loss in distribution network which is radial in nature, the solution methodology adopted in this paper is optimal placement of distributed generators (DG). The optimization incorporated is Multi-objective Grey Wolf Optimization (MOGWO). The optimization is accomplished for three different cases. In each case two objective functions are simultaneously optimized to obtain non-dominated solutions using Multi-objective Grey Wolf Optimization. Case (1): To minimize the real power loss and maximize the savings obtained due to DG installation. Case (2): To minimize real power loss and maximum voltage deviation in the network. Case (3): To minimize real power loss and rating of DG installed. MOGWO method maintains an archive which contains pareto-optimal solutions. The archive mimics the behaviour of grey wolves. MOGWO method is verified on radial distribution networks. The effectiveness of the optimization method is proven by comparing the results with other optimization methods available in the literature.

100+ Gbps/λ 50 km C-Band Downstream PON Using CD Digital Pre-Compensation and Direct-Detection ONU Receiver

We experimentally demonstrate a single-wavelength 100 Gbps downstream PON transmission aided by chromatic dispersion digital pre-compensation (CD-DPC) using simple digital signal processing (DSP) finite impulse response (FIR) filters in combination with an IQ Mach–Zehnder modulator (IQ-MZM) at the transmitter side and direct-detection receiver at the optical network unit (ONU). A reach of 50 km over standard single-mode fiber in C-band and an optical distribution network (ODN) loss of 28.5 dB are achieved. Transmission of 50 and 125 Gbps over 50 km of fiber is also tested, achieving 32 dB and 24 dB of ODN loss, respectively. The complexity of the filters, the optimization of the main design parameters, and the tolerance of the CD-DPC to the uncertainty of the exact accumulated link dispersion are analyzed in detail.

Discharge coefficient equation to calculate the leakage from pipe networks

With the increasing of urbanization, water distribution networks play an important role in human life and the effective use of water resources. Therefore, studies have been made for the optimization of water distribution networks in some fields such as pressure management and leakage control. In this context, the discharge coefficient, which is one of the components of the hydraulic calculations, is a very significant parameter in calculating the losses. In this study, a new equation has been proposed to calculate the discharge coefficient. Computer simulations were done by using ANSYS Fluent and discharge coefficient values were determined for round holes. Firstly, the model validated with theoretical Toricelli (orifice) equation and then, the model was run for number of scenarios according to various internal pressure and hole areas. The model results were formulated by means of regression equations. To satisfy the dimensional homogeneity, the ratio of the hole area to the pipe cross-sectional area, area ratio (r), and the ratio of the internal pressure to the external pressure, pressure ratio (p), were used. In this study, easy to use discharge coefficient equation was proposed to calculate the leakage losses in water distribution networks. With the help of this equation, the discharge coefficient can be calculated precisely for different pressure values and leakage areas rather thantaken as a constant value. Thus, the calculation of the leakage flow rate will be more accurate. Furthermore, it is concluded that the dicharge coefficient varies between 0.65 and 0.72. There is also inverse realtionship between discharge coefficient and pressure and discharge coefficient and leakage area.

A forward‐backward sweep based numerical approach for active power loss allocation of radial distribution network with distributed generations

AbstractIn this paper, a new active power loss allocation (LA) technique is proposed for allocation of network losses among its participants in a deregulated power environment. This method employs a forward‐backward sweep (FBS) based numerical technique for system load flow (LF) and power loss calculation with/without distributed generators (DGs). The complexity lying with the decomposition of cross‐term of power loss equation has been simplified mathematically, without any assumptions and approximations. The proposed LA establishes a direct relationship between two end voltages of a branch and its subsequent node currents in terms of node injected complex powers. It assigns losses to the end‐users with due consideration to their load demands and geographical locations. The penetration of DGs may increase/decrease loss of a power distribution network. In order to provide justice to the DG owners, this paper proposes a new DG remuneration technique, which assigns either incentives/penalties to the DG units after analyzing their exact impact toward network loss reduction/enhancement, without diverting any part toward the consumers' side compared to other established methods. The effectiveness of the proposed algorithm is investigated using a 33‐bus test system considering: various load levels, several DG capacities and different types of DG power injections. The results obtained highlight the efficiency and applicability of the present approach as compared to other established techniques.

Analysis of energy revenue and electrical power losses in distribution line

This study presents the analysis of energy revenue and electrical power losses in distribution network, aimed to determine the energy losses on power distribution system. The 11kV power transmission line at Ujokuen community feeding to Benson Idahosa University was investigated. The following data were obtained as follow: energy delivered, energy billing, total cash amount, billed collected and correspond percentage. From the research work various technical power losses associated with power distribution network were determined and their effect on energy delivered and energy billing and corresponding difference under the area of investigation. It was observed that energy delivered is not constant or linear for the year 2013. The comparison of energy delivered and energy billed for various years were determined. It was observed that there is decreased in energy delivered and energy billed from 2013 to 2015 and the system witnessed a slightly increase of energy delivered and energy billed from 2016 to 2018. The energy level differentials are due to copper losses, energy theft and core loss.

An Analysis of the Cost of Water Supply Linked to the Tourism Industry. An Application to the Case of the Island of Ibiza in Spain

Tourist activity has a number of impacts on the destinations in which it takes place, among which are the environmental ones. A particular problem is the increase in water demand and wastewater production, which can compromise the balance of ecosystems. As many authors point out, there is a research gap in the comparative analysis between available water resources and the demand associated with tourism. In this respect, the main objective of this work is, on the one hand, to assess the water needs linked to the tourism industry and the capacity of natural resources to meet such a demand and, on the other hand, to estimate the economic cost of the water supply associated with the growing tourist demand in a territory, such as the island of Ibiza in Spain. It has been determined that the resources available are not sufficient to meet the water demand of the resident population at this destination, which is why it is necessary to resort to producing desalinated water. Therefore, the additional requirements associated with tourism must be met fully with desalinated water, which results in an increased cost of water management for the region. This paper also points at water losses in distribution networks and tourism seasonality as two phenomena that aggravate this issue.

Data mining for abnormal power consumption pattern detection based on local matrix reconstruction

Electricity theft is the main reason for non-technical losses (NTL) in distribution networks, which can lead to great economic losses in power supply enterprises. Efficient and accurate detection of abnormal power consumption patterns is a key part of demand side management. With the popular use of smart meters, it is more efficient and reliable to collect customers’ power consumption data, which make on-line monitoring of power consumption possible. In this paper, a detection algorithm based on local matrix reconstruction (LMR) is proposed and utilized to detect abnormal power consumption patterns in power systems. In this algorithm, five daily load characteristics are used to replace high-dimensional daily load curves to characterize power consumption patterns. Then, principal component analysis (PCA) is applied to calculate weighted reconstruction errors in a local scope. The reconstruction error of each sample is compared with its adjacent samples in order to calculate local outlier scores, which represent the abnormal degree of each load sample. Using two open source datasets, the detection performance of the proposed method is verified to be effective and efficient.

A two-layer two-stage dispatching strategy for active distribution network with micro-grid considering multiple interactions

In order to strengthen the interaction ability between the active distribution network and multiple micro-grids, the micro-grid and micro-grid, the source and load, this paper proposes a day-ahead dispatching optimization strategy for active distribution network with multiple micro-grids under multiple interactions. Some comparisons were made with other dispatching strategies to verify the effectiveness of the proposed strategy. A two-layer two-stage dispatching model was constructed. The minimum active power loss of active distribution network is regarded as the objective function at the upper layer. The comprehensive optimization of economy and environmental protection of micro-grid is taken as the objective function of the first stage, and the minimum power unbalance is taken as the objective function of the second stage at the lower layer. In our strategy, the node voltage, state of charge of energy storage equipment and unbalanced interactive power of the tie line were set as off-limit penalties to ensure the normal operation of the each system. Meanwhile, the comprehensive benefits of each target subjects were taken into account. An improved IEEE 14 node example system was set up as the upper layer active distribution network, and five-machine eight-terminal loop system as the lower layer micro-grid. With the aid of artificial fish swarm and the non-dominant sorting genetic algorithm-Ⅱ to solve and optimize the equation and parameters, the feasibility and effect of dispatching strategy and model were verified. The results show that the strategy proposed in this paper can effectively reduce the loss growth rate of active distribution network and improve the comprehensive benefit of each micro-grid.

Mitigate the Distribution Network Loss and improve the Reliability Based on Deep Learning Algorithm

Mitigate the Distribution Network Loss and improve the Reliability Based on Deep Learning Algorithm

An Analytical Method for Designing of Municipal Water Supply and Distribution Systems

The clean Water Supply provision is one of the major factors greatly contributing to the socioeconomic transformation of a country. However, many countries have problems in fulfilling the water demand of the continuously growing population and populated areas due to the high level of water losses in distribution networks. Optimization of water distribution system design is one of critical research fields, which has been extremely productive. Its primary focus is to minimize the cost of a proposed pipe network infrastructure. The paper presents the results of research on the development of a new analytical design method that allows creating new water distribution systems or strengthening, expanding and rehabilitating existing water distribution systems, inclusive of design timing, parameter uncertainty, water quality, and other operational considerations. The method is based on the solution of hydraulic problem of a linear pipeline and the use of the newly developed software set for studying hydraulic processes. The solution is determined in the Mixed Integer Programming - MIP and Discontinuous Nonlinear Programming - DNLP connection modes. As research results show it is possible to expand and solve the problems of finding the locations of branching optimal lines connecting the sources (main distribution systems) and consumers. The task set and its solution opens a whole range of opportunities for its successful application in the most diverse branches of science and production.

A novel energy-reliability market framework for participation of microgrids in transactive energy system

This paper proposes a novel framework for a distribution level transactive energy system in order to facilitate energy transaction among microgrids while improving efficiency and reliability of distribution system. The proposed market mechanism simultaneously considers competition among participants, distribution network reliability and operation conditions. To improve the reliability of supply, a reputation system is proposed, which ranks energy suppliers according to a reputation index based on their long term energy transaction history. A demand-oriented approach is utilized for extracting local energy prices. The local energy pricing scheme is based on combination of reputation scores, loss reduction indices and demand-side offering prices. A secondary market is proposed to use the capacity of energy suppliers for reliability support service in distribution network. The local pricing scheme for the reliability market is based on outage scenarios and customer interruption penalties. It is shown that the proposed model enforces energy suppliers to honor their generation commitments and prevents them from greedy behavior in the market. The energy market mechanism improves the reliability of supply and intensifies competition among participants. This mechanism directly reduces active power losses in distribution network and indirectly improves nodal voltage and branch loading profile. Moreover, utilizing the capacity of microgrids in improving the reliability of network, postpones network reinforcement investments needed for keeping the service continuity indices in acceptable range.

Optimization of capacitor capacity to reduce electric power losses in distribution networks in Jampang Kulon Sukabumi

The electric power system consists of three main parts, one of which is the distribution system. The distribution system has the role of channeling electrical energy from the substation to the consumer. In the distribution of electric power, high reliability is needed so that the quality of electric power is maintained well. There are many factors that can reduce power quality, including power losses. One effort to maintain the quality of electrical power by reducing electrical power losses is to install capacitors on distribution channels. The capacitor is installed as a reactive power compensator so that the power factor approaches 1. In the Jampang Kulon feeder, there are considerable power losses, namely on bus 85-16-1 at 61.6 kW and bus 86-14-1 at 16.5 kW. By determining the capacitor capacity using ETAP, a 3 x 900 kVAR capacitor is mounted on bus 85-16-1 and a 3 x 300 kVAR capacitor on bus 86-14-1. The highest reduction in power losses occurred on buses 85-16-1 and buses 82-17-1. On bus 85-16-1 the power losses have decreased from 61.6 kW to 50 kW (reduced by 11, 6 kW), while on bus 82-17-1, the power losses have decreased from 59.4 kW to 49.2 kW (reduced by 10.2 kW).