Implementation Of Distributed Generation Research Articles

Power-Flow Simulations for Integrating Renewable Distributed Generation from Biogas, Photovoltaic, and Small Wind Sources on an Underground Distribution Feeder

The rapid expansion of distributed generation leads to the integration of an increasing number of energy generation sources. However, integrating these sources into electrical distribution networks presents specific challenges to ensure that the distribution networks can effectively accommodate the associated distributed energy and power. Thus, it is crucial to evaluate the electrical effects of power along the conductors, components, and loads. Power-flow analysis is a well-established numerical methodology for assessing parameters and quantities within power systems during steady-state operation. The University of São Paulo’s Cidade Universitária “Armando de Salles Oliveira” (CUASO) campus in São Paulo, Brazil, features an underground power distribution system. The Institute of Energy and Environment (IEE) leads the integration of several distributed generation (DG) sources, including a biogas plant, photovoltaic installations, and a small wind turbine, into one of the CUASO’s feeders, referred to as “USP-105”. Load-flow simulations were conducted using the PowerWorldTM Simulator v.23, considering the interconnection of these sources. This dataset provides comprehensive information and computational files utilized in the simulations. It serves as a valuable resource for reanalysis, didactic purposes, and the dissemination of technical insights related to DG implementation.

Improving the Power Supply Performance in Rural Smart Grids with Photovoltaic DG by Optimizing Fuse Selection

The recent increase in the use of renewable sources in electrical systems has transformed the electrical distribution network with the subsequent implementation of the distributed generation (DG) concept. The high penetration level of photovoltaic units increases their injected fault current that may result in a lack of coordination of fuse reclosers in distribution networks. One of the main protection devices that is generally used in rural distribution networks is the fuse. A correct size selection is key for ensuring good operation and coordination with other protection devices. The DG implementation makes the selection above more difficult, as the current flow both in steady state and in case of short-circuit is subject to alterations. A new protection fuse selection method for distribution networks with implemented DG is proposed in this paper with the aim of ensuring an effective coordination between them, avoiding untimely behaviors. Different case studies have been analyzed (for diverse locations of DG in the network with various penetration levels which represent 25%, 50%, 75%, and 100% of the total installed load), using an IEEE 13-node test feeder. Besides, a new model to analyze fuse performance is proposed in this work. This model has proven to fit the manufacturer’s data well, with a maximum error of 2% within the normal trip current values.

A branch oriented active power loss allocation method for radial distribution networks with distributed generators

The penetration of distributed generation (DG) units in the radial distribution network (RDN) introduces complexity in active power loss allocation (LA) as it leads to reverse current in the network. This current makes power system bidirectional and brings difficulties in the decomposition of cross-terms of power loss equation. To overcome such complications, this paper proposes a new branch oriented LA technique which eliminates the impact of mutual-term mathematically from loss formulation without any assumptions and approximations. It establishes a direct relationship between the subsequent load currents of a branch and its two end voltages in terms of the complex power available at its load ends. The proposed LA scheme is found to be fair as regard to the topology of the RDN. Further, the implementation of DGs may increase/decrease power loss of a system. In order to provide the exact amount of loss reduction benefit to the DG owners (DGOs), a new DG remuneration strategy is developed in this paper which assigns either rewards/penalties to the DGOs after analysing their actual impact towards system loss reduction. The effectiveness of the proposed LA method is investigated against various established LA techniques using two different test systems i.e., 17-bus and 33-bus RDNs.

Role Analysis of Distributed Generation Towards Transmission Expansion Planning Using MILP

Electricity demand increase as function of population and economic activity growth. To meet the demand growth, one kind of approaches to expand electrical system is to calculate the need of generating unit and the result will be used to determine the needs of transmission line. In this research, a model was developed with focused on transmission line expansion based on Mix Integer Linear Programming method. The objective function was to minimize overall investment cost for transmission and operating cost of all generating units. The developed model was implemented in 6-bus Garver’s test system. Distributed generation implementation impact is also studied in this study in term of network configuration and overall expansion cost. The results show that distributed generation implementation will differ the network configuration and reduce the overall system cost, with overall system cost with and without distributed generation implementation was $106.4 million and $103.18 million respectively.

Integrated and Simultaneous Model of Power Expansion Planning with Distributed Generation

This study proposes a model based on mixed-integer linear programming (MILP) for the integrated expansion planning of generation and transmission systems with the implementation of distributed generation (DG). Most DG planning takes place after generation and transmission planning has been conducted. This model can be used to include DG potential simultaneously with generation and transmission expansion. DG is modelled as a negative load therefore DG is treated as a non-dispatchable unit of power generation. The objective of the model is to minimize overall cost including the investment cost of the generation units, DG units, and transmission lines, and the operating cost of the generation and DG units. The proposed model is static-deterministic model in the form of MILP. The model was evaluated using the 6-bus Garver’s test. To prove the effectiveness of the model, it was evaluated using the IEEE 46 Bus Test. The results show that due to the impact of DG on power system expansion planning ,the overall cost was reduced. The simulation results also show that a different optimal network configuration can be achieved by DG implementation in expansion planning.

An optimization algorithmfor industrial power supply systems in a processof distributed generation implementation

An optimization algorithmfor industrial power supply systems in a processof distributed generation implementation

Analysis of Stability of Tension and Losses of Electric Power in Distribution Networks with Distributed Generation

This document intends to develop a study on tension analysis considering renewable or non-conventional energy for implementing distributed generation (DG), as a solution to the problem generated in the electrical power system (EPS) due to disturbances that affect it. One of the problems is the lack of active power supplied to the system, which is compensated by the inclusion of distributed generation; otherwise it is considered the instability criterion harming the system itself and the consumer receiving the service. Based on the study of voltage stability, a radial system of 9 bars was established, in which sources of distributed generation were implemented and the effects that occurred in low, medium and high impact were analyzed. The analysis was developed with the help of literary sources as a basis for the study, which were applied in the ETAP software, allowing us to establish the characteristics of the system by performing simulations in the power flow in various scenarios. The method of analysis allowed to establish margins and rates of voltage stability by varying the active power supplied by the EPS, so that the relation between the voltage and the power made possible to determine the characteristics of the system, setting the system operation under normal operating limits. The operating conditions in the EPS are some of the limitations that nullify the idea of introducing a system with DG, since the system as such does not have the capacity to install generation centers in the system randomly. For this, we included studies on the analysis of an optimal location to find the proper implementation of DG in the EPS. The results obtained were optimized using the GAMS software assessing the cost functions, which allowed us to analyze the importance of the implementation of DG in technical and economic aspects of the distribution system.

Maintaining the rated level of power supply reliability under the condition of distributed generation implementation

In order to minimize costs of power supply companies and potential investors, the study related to the formation of a strategy to ensure the rated level of power supply reliability in conditions of integration of distributed generation sources into electrical networks is carried out in the paper. The possibility of the logframe use to evaluate the integrated reliability indicators in the conditions of equipment of electrical networks with modern switching devices and presence of generating sources under different settings and locations is shown. The experimental computations reveal that only a coordinated solution of the problems of electrical network partitioning in terms of reliability optimization and implementation of technical specifications to enable their island mode at the occurrence of distributed generation sources makes it possible to make the most cost-effective decisions. The results can be directly used in the practical work of operational units and prospective development departments of energy supply companies, serve as an important component in the multicriteria evaluation of application options of distributed generation.

Application of Particle Swarm Optimization for Optimal Distributed Generation Allocation to Voltage Profile Improvement and Line Losses Reduction in Distribution Network

Distributed Generation (DG) had created a challenge and an opportunity for developing various novel technologies in power generation. The rate and size of DG implementation have o be determined. The increasing need of electricity and establishing powerhouses, as well as to spend a great amount of time to build powerhouses, indicate the necessity of distributed generation in small size and close to the consumer location. In this study, selecting a part of Tehran network, attempts to investigate the effects of distributed generation on line losses and voltage profile using PSO. The introduction of PSO based DG in a distribution system offers several benefits: Significant voltage profile improvement, Considerable line loss reduction, Improves system reliability and etc. The optimum value of the DG, also obtained increases the maximum load ability of the system. The proposed method is tested on a system and the results of the simulation carried out will be given. Finally the results are compared to system without installation DG. The method has a potential to be a tool for identifying the best location and rating a DG to be installed for improving voltage profile and reduce losses.

Application of Intelligent Algorithms for Optimal Distributed Generation Allocation to Voltage Profile Improvement and Line Losses Reduction

Distributed Generation (DG) had created a challenge an opportunity for developing various novel technologies in power generation. The rate and of DG implementation have to be determined. The increasing need of electricity and establishing powerhouses, as well as spending a great amount of time to built powerhouses, indicate the necessity of distributed generation in small size and close to the consumer location. In this study selecting IEEE-14 bus systems, attempt to investigate the effect of distributed generation in line losses and voltage profile by using two optimization techniques. The introduction of PSO and CSA base DG in a distribution System offer several benefits: Significant voltage profile improvement, Considerable line loss reduction, improves system reliability and etc. The optimum value of DG, also obtained increasing the maximum load ability of the system. Finally the results are compared to a system with and without installation DGs.

A novel adaptive current protection scheme for distribution systems with distributed generation

An adaptive current protection scheme is proposed for the protection of power systems with penetration of distributed generation (DG). In this scheme, steady state fault current of the related power transmission lines is derived from steady state network equivalent reduction. Then, settings criteria for adaptive primary and backup protection are established on the basis of the steady state fault current. The simulated results of a realistic power network verify the ranges of adaptive primary and backup protection are immune to implementation of DG and the fault types. Furthermore, compared with traditional current protection schemes, the proposed method has extended the primary and backup protection regions considerably.

Distribution network planning method considering distributed generation for peak cutting

Conventional distribution planning method based on peak load brings about large investment, high risk and low utilization efficiency. A distribution network planning method considering distributed generation (DG) for peak cutting is proposed in this paper. The new integrated distribution network planning method with DG implementation aims to minimize the sum of feeder investments, DG investments, energy loss cost and the additional cost of DG for peak cutting. Using the solution techniques combining genetic algorithm (GA) with the heuristic approach, the proposed model determines the optimal planning scheme including the feeder network and the siting and sizing of DG. The strategy for the site and size of DG, which is based on the radial structure characteristics of distribution network, reduces the complexity degree of solving the optimization model and eases the computational burden substantially. Furthermore, the operation schedule of DG at the different load level is also provided.

Implementation of Distributed Generation (IDG) algorithm for performance enhancement of distribution feeder under extreme load growth

This paper presents a new algorithm, written in C-language for Implementation of Distributed Generation (IDG) to radial distribution feeder, heavily overloaded with non-uniformly distributed load. Majority of the existing algorithms are designed for distribution feeders with uniformly distributed load, working in single DG scenario. The applicability of these algorithms is restricted because of the unity power factor and high computational work. The methodology proposed in the research paper is capable of functioning under randomly distributed load conditions with low power factor for single DG as well as multi-DG system. The algorithm is based on analytical approach and is implemented to radial distribution network, considering the worse case scenario. The analyses carried out show that the algorithm can be applied to enhance the performance of distribution system in terms of node voltage profile improvement and power loss reduction. The simulation results indicate that IDG is capable of identifying the optimal location and size of DG in any problematic distribution system effectively. The results obtained are verified and are within the international standards limits.

Restoration of Directional Overcurrent Relay Coordination in Distributed Generation Systems Utilizing Fault Current Limiter

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> A new approach is proposed to solve the directional overcurrent relay coordination problem, which arises from installing distributed generation (DG) in looped power delivery systems (PDS). This approach involves the implementation of a fault current limiter (FCL) to locally limit the DG fault current, and thus restore the original relay coordination. The proposed restoration approach is carried out without altering the original relay settings or disconnecting DGs from PDSs during fault. Therefore, it is applicable to both the current practice of disconnecting DGs from PDSs, and the emergent trend of keeping DGs in PDSs during fault. The process of selecting FCL impedance type (inductive or resistive) and its minimum value is illustrated. Three scenarios are discussed: no DG, the implementation of DG with FCL and without FCL. Various simulations are carried out for both single- and multi-DG existence, and different DG and fault locations. The obtained results are reported and discussed. </para>

A methodology for developing Distributed Generation scenarios in urban areas using geographical information systems

The implementation of Distributed Generation (DG) may lead to increased pollutant emissions that adversely affect air quality. This work presents a systematic methodology to characterise DG installation in urban basins. First, a set of parameters that characterise a DG implementation scenario is described. Second, a general approach using Geographic Information Systems (GIS) data is presented. Third, the methodology is demonstrated by application to the South Coast Air Basin (SoCAB) of California. Results show that realistic scenarios in the SoCAB concentrate DG technologies nearby industrial zones and introduce pollutant mass increments no larger than 0.43% with respect to baseline emissions.

Air quality impacts of distributed power generation in the South Coast Air Basin of California 2: Model uncertainty and sensitivity analysis

Uncertainty and sensitivity of ozone and PM 2.5 aerosol to variations in selected input parameters are investigated with a Monte Carlo methodology using a three-dimensional air quality model. The selection of input parameters is based on their potential to affect concentration levels of ozone and PM 2.5 predicted by the model and to reflect changes in emissions due to the implementation of distributed generation (DG) in the South Coast Air Basin (SoCAB) of California. Numerical simulations are performed with the CIT air quality model. Response of the CIT predictions to the variation of selected input parameters is investigated to separate the potential air quality impacts of DG from model uncertainty. This study provides a measure of the model errors for selected species concentrations. A spatial sensitivity analysis is used to investigate the effect of placing DG in specific regions of the SoCAB. In general, results show that confidence in the model results is greatest in locations where ozone and PM 2.5 concentrations are the highest. Changes no greater than 80% in the nominal values of selected input variables, cause changes of 18% in ozone mixing ratios and 25% for PM 2.5 aerosol concentrations. Sensitivity analysis reveals that nitrogen oxides ( NO x ) emissions and side boundary conditions of volatile organic compounds (VOC) are the major contributors to uncertainty and sensitivity of ozone predictions. An increase in NO x emissions leads to reductions in ozone mixing ratios at peak times and sites where the maximum values are located. PM 2.5 aerosol is most sensitive to changes in NH 3 and NO x emissions. Increasing these emissions leads to higher aerosol concentrations. Sensitivity analyses show that the impacts of DG implementation are highly dependent on both space and time. In particular, ozone concentrations are reduced during the nighttime nearby locations where DGs are installed. However, during the daytime ozone concentrations increase downwind from the sources. A major finding of this study is that the emissions of DG installed in coastal areas produce a significant impact on the production of ozone and PM 2.5 aerosol in the eastern regions of the SoCAB.

Air quality impacts of distributed power generation in the South Coast Air Basin of California 1: Scenario development and modeling analysis

Distributed generation (DG) is generally defined as the operation of many small stationary power generators throughout an urban air basin. Although DG has the potential to supply a significant portion of the increased power demands in California and the rest of the United States, it may lead to increased levels of in-basin pollutants and adversely impact urban air quality. This study focuses on two main objectives: (1) the systematic characterization of DG installation in urban air basins, and (2) the simulation of potential air quality impacts using a state-of-the-art three-dimensional computational model. A general and systematic approach is devised to construct five realistic and 21 spanning scenarios of DG implementation in the South Coast Air Basin (SoCAB) of California. Realistic scenarios reflect an anticipated level of DG deployment in the SoCAB by the year 2010. Spanning scenarios are developed to determine the potential impacts of unexpected outcomes. Realistic implementations of DG in the SoCAB result in small differences in ozone and particulate matter concentrations in the basin compared to the baseline simulations. The baseline accounts for population increase, but does not consider any future emissions control measures. Model results for spanning implementations with extra high DG market penetration show that domain-wide ozone peak concentrations increase significantly. Also, air quality impacts of spanning implementations when DG operate during a 6-h period are larger than when the same amount of emissions are introduced during a 24-h period.

Improvement of power supply to rural customers through grid-interactive distributed generation

The integration of Distributed Generation (DG) into distribution grid systems introduces problems in network operation, control and protection. Key issues associated with DG inclusion are voltage or current control, cost-effective operation, protection coordination and network transients. Better understanding of these issues and finding solutions to these problems are important to power industries. This paper has addressed the general issues and problems of DG implementation, and presented solutions for effective operation and control of the DG system. The impact of DG on distribution protection has been investigated and the level of fault contribution by DG during a fault has been determined. The contribution of DG to the improvement of power quality and reliability has been examined. Mitigation of voltage dip transients and reduction of harmonics in the network by DG have been analysed through modelling and simulations. Also, criteria to select DG technology and safety issues with DG integration have been discussed.