Planning Of Electric Networks Research Articles

Energy Losses Estimation in Power Distribution Systems

Estimating technical losses is fundamental to the planning and economics of electric power networks. This paper surveys the evolution of the ideas behind energy loss estimation and focuses on the development of the concepts of the loss factor and equivalent hours. The paper next identifies difficulties in using maximum demands and the loss factor to estimate energy losses. Based on this analysis, this study proposes an alternative loss estimation approach that relies on the “loss coefficient” as the fundamental parameter for describing load variations in loss estimation. A large load-curve data bank from Brazilian utilities is used to characterize load-curve parameters and provide perspective on the old and new concepts. Practical applications put the proposed ideas into perspective, showing how the use of average demands and loss coefficient can help to make better cable choices, increase accuracy in loss estimation for distribution transformers, and enhance the quality of information in loss estimation analysis.

Incorporating weather uncertainty in demand forecasts for electricity market planning

A major component of electricity network planning is to ensure supply capability into the future, through generation and transmission development. Accurate forecasts of maximum demand are a crucial component of this process, with future weather conditions having a large impact on forecast accuracy. This article presents an improved methodology for the consideration of weather uncertainty in electricity demand forecasts. Case studies based on the Australian national electricity market are used to validate the proposed methodology.

Guide to electricity network design and planning – part 1

This is part 1 of a three-part guide aimed at qualified engineers and/or graduates who are beginning their career in an electricity distribution network planning department, or perhaps moving into a planning role after some years in a different role (for example operations, maintenance or construction). The focus is on distribution rather than transmission planning. Nevertheless, the general principles are essentially similar, and since the distinction between the two is becoming increasingly blurred given the proliferation of distributed generation and energy resources, planning engineers new to either discipline should find the three parts of this guide useful. Part 1 covers the general principles of network design and planning, security of supply, network design basics, voltage management, load forecasting, electrical losses, and analysis and modelling. It includes a useful 21-point check list which planning engineers may find useful when preparing proposals for network investment. The two complementary parts of this guide are: Part 2 – which covers legislation and regulation, quality of supply, engineering recommendations and technical reports, investment appraisal, low carbon transition, and innovation and smart grids; and Part 3 – which covers the basics of protection and overall protection schemes.

Guide to electricity network design and planning – part 2

This is part 2 of a three-part guide aimed at qualified engineers and/or graduates who are beginning their career in an electricity distribution network planning department, or perhaps moving into a planning role after some years in a different role (for example operations, maintenance or construction). The focus is on distribution rather than transmission planning. Nevertheless, the general principles are essentially similar, and since the distinction between the two is becoming increasingly blurred given the proliferation of distributed generation and energy resources, planning engineers new to either discipline should find the three parts of this guide useful. Part 2 covers legislation and regulation, quality of supply, engineering recommendations and technical reports, investment appraisal, low carbon transition, and innovation and smart grids. The two complementary parts of this guide are: Part 1 – which covers the general principles of network design and planning, security of supply, network design basics, voltage management, load forecasting, electrical losses, and analysis and modelling. It includes a useful 21-point check list which planning engineers may find useful when preparing proposals for network investment; and Part 3 – which covers the basics of protection and overall protection schemes.

Guide to electricity network design and planning – part 3

This is part 3 of a three-part guide aimed at qualified engineers and/or graduates who are beginning their career in an electricity distribution network planning department, or perhaps moving into a planning role after some years in a different role (for example operations, maintenance or construction). The focus is on distribution rather than transmission planning. Nevertheless, the general principles are essentially similar, and since the distinction between the two is becoming increasingly blurred given the proliferation of distributed generation and energy resources, planning engineers new to either discipline should find the three parts of this guide useful. Part 3 – which covers the basics of protection and overall protection schemes. The two complementary parts of this guide are: Part 1 – which covers the general principles of network design and planning, security of supply, network design basics, voltage management, load forecasting, electrical losses, and analysis and modelling. It includes a useful 21-point check list which planning engineers may find useful when preparing proposals for network investment; and Part 2 - which covers legislation and regulation, quality of supply, engineering recommendations and technical reports, investment appraisal, low carbon transition, and innovation and smart grids.

Electricity Network Planning: The Key to Efficient and Reliable Power Supply to Consumers

This paper focuses on the need and procedure for the planning of electrical engineering infrastructure for any district/community in order to enhance reliability and efficiency of power supply to consumers. Almost all the towns/cities in Nigeria are unplanned and this has resulted in haphazard approach to Electricity Network Planning and implementation. A detailed theory, methodology and technical considerations, in compliance with both National and International standards are discussed in this paper. A proposed University campus was used to demonstrate the procedures involved in electricity network planning in order to achieve an efficient power supply. This involves the electric power supply, design concepts, load estimates and analysis, network distribution/equipment and sizing of cables and electrical panels taking into account the various modes of distribution. This paper also drew a simple analogy between Benin City and the Federal Capital Territory, Abuja, to illustrate the objective of the paper while highlighting the merits associated with planned electrical engineering infrastructure and suggested the ways to remedy the unplanned networks in Nigeria.

FUZZY EVALUATION MODEL FOR UNCERTAINTIES IN ELECTRICAL NETWORK PLANNING

Several methods for dealing uncertainties in electrical network planning are compared and analysed. Fuzzy evaluation model with the blind number representing uncertainties in electrical network planning is proposed. The model well describes the planner's satisfaction degree with respect to the economic objective and reliability objective of the planning scheme, and is more universal to deal with the uncertainties inherent in the planning. Moreover, the model is suitable to be processed by the meta-heuristic algorithms and the computation burden brought by massive information processing can be reduced by the proposed techniques. Finally, the model is illustrated and justified by an 18-bus sample system.

Strategic expansion planning for electrical networks considering uncertainties

This article describes a newly developed method for expansion planning of electrical networks with respect to long-term cost-efficient target networks that have been calculated beforehand. Unlike existing methods, the proposed method does not calculate discrete points in time for the realization of expansion steps, but optimal if/then-relations between expansion steps and uncertainties of network planning. The results of the expansion planning process are, therefore, optimal strategies for the future development of existing networks. Additionally, uncertainties of network planning can be considered in a more effective way by describing expansion strategies in relation to these uncertainties. Thereby, not only the computation time for solving the optimization problem has been reduced significantly but also an exponentially growing computational effort has been avoided. The developed method is based on Ant Colony Optimization (ACO). Heuristic rules have been derived in order to improve the efficiency of the optimization approach. Since long-term cost-efficient target networks define the network structure that should be reached in the future, no explicit optimization of the network topology is necessary. Thus, different voltage levels can be optimized in one integrated approach with the developed method. An exemplary case study presented in this article proves the functionality of the developed method. Copyright © 2006 John Wiley & Sons, Ltd.

Outage planning of electrical power system networks using genetic algorithm

An electrical company is responsible for the maintenance of a transmission network of high voltage electricity. The maintenance schedule must be planned so as to minimize outage costs, taking into consideration various factors such as system security/reliability, system availability, and manpower utilization. With the rapid growth of organization, planning engineers are required to fulfill additional roles in order to increase productivity. To this end, a fast response and accurate mechanism is required to assist the planning engineers in dealing with the daily operation. This paper describes how a proposed maintenance schedule can be obtained automatically by the adoption of genetic algorithm. The main aim is to determine the maintenance schedule of circuit outage with minimizing the maintenance cost and maximizing the circuit availability under certain unavoidable system constraints. Further, an additional search mechanism called “final tuning search” is developed to enhance the system performance.

Demand-side management in the electricity sector: Implications for town planning in the UK

This paper examines the relationship between the land use planning system and two innovative demand-side management (DSM) initiatives in the UK electricity sector. In contrast to conventional supply-orientated approaches to infrastructure management, DSM encourages the utility to consider the role of energy conservation and efficiency measures to avoid or delay the need for new investment in supply-side infrastructure. Although it might be expected that DSM measures would require much closer coordination between land use and electricity network planning, there was little evidence of the development of these links in the case studies. Instead the paper concludes that, through the adoption of DSM approaches to network management, utilities are developing their own ideas about the socioeconomic and spatial development of the territories they serve with little connection back to traditional land use planning processes.

Ranking and postponement of investments in planning the Serbian electric power networks

A method for ranking and postponing investments during the planning of electrical power networks is presented. The probabilistic economic criterion which takes into consideration the cost of expected undelivered energy is used to derive a profitability index, a postponement index and combined technical-economical-probabilistic planning criteria. The method allows the ranking and the postponement of technically justified but economically unjustified investments which is especially useful when insufficient investment funds are available for construction.

Discrete optimization and the planning of electric power networks

Power system transmission planning is expressed as a large finite Markovian sequential process over time involving 1) a known planning horizon divided into finite number of stages; 2) a large number of alternative additions (type, size, and place of new facilities) at each stage; 3) analysis and criteria for evaluating network acceptance (performance, reliability, security, cost, etc.) for each alternative at each stage; 4) a searching method to find the optimum plan. Forward dynamic programming is used to maximize the utility of the transmission network over the period of the planning horizon ensuing adequate service, and the results show the effects of economy of scale as the planning horizon is increased. However, dynamic programming is limited by the number of alternatives considered at each stage. Thus a new method, discrete dynamic optimizing (DDO), is also introduced.