EPQU Magazine - Vol 1 Issue 2

Arjen G. Jongepier, Walter T.J. Hulshorst, Gabriël A. Bloemhof, KEMA, The Netherlands

As a consequence of the liberalization of energy markets, grid owners and operators (including industries and railways) are re-orientating on asset management and investments. The regulatory authorities, involved in sustaining security, reliability and availability of supply, represent the society's requirements that grid companies have to cope with, under their financial and corporate policies, limitations and targets.

Quality of supply is of major social concern. Grid companies and regulators have to decide at what costs this is achieved and sustained. On the customers side there is a growing awareness for the quality of supply, of which reliability of the grid is an important factor. To balance sustaining or improving the quality of supply with the cost consequences of investments in power systems, quantification is unavoidable.

The combination of available outage data, the valuation of outages to customers and new probabilistic tools, makes it possible to find the social optimum for power system design under the new quality regulation and increasing planning uncertainties.

These analyses typically result in investment and management decisions that combine the social, legal, technical and financial risks, cash-outs and revenues.

Miklós Horváth, József Borka, Power Electronics Department, Computer and Automation Research Institute, HAS, Hungary

The concept considers the solution of problems as follows: the rational improvement of the quality of electric power in public utility line and the energy saving of DC electric energy distribution, furthermore, the connection of the environment-friendly, local, alternative energy sources to the electric energy system. The development of a reference system for the elaboration and realisation of the suggestion during a long period would be important, which makes the solution of foreseen and unforeseen problems possible. The paper outlines the layout, the advantages and risk factors of the system proposed.

Peter G.V Axelberg, Unipower AB, Sweden

Traditionally the control and supervision of a power network has mainly been focused on the operation of the network or for protecting system components during fault conditions etc. Relatively little attention has been focused on the product itself – the electrical energy. This old approach is now changing since many processes in the modern society are depending on having access to electrical energy with high reliability and quality. The trend among energy suppliers and power quality sensitive industries is to put increased focus on the supervision of the power quality in order to detect power quality disturbances before they cause unplanned interruptions etc. This paper discusses a system – Quality Information System – for permanent monitoring of power quality. The paper also discusses the new standard IEC 61000-4-30. This standard defines calculation schemes for the most important power quality parameters. The paper also discusses a monitor that is producing power quality information in accordance with this new standard.

Bora ALBOYACI, Nuran YORUKEREN, Hasan Basri CET

This paper presents the results of investigating harmonic levels on medium voltage motors at loading conditions in air separation plants. The essential results of the measurement of the medium voltage motor harmonics are summarized in the values for the total harmonic distortion (THD). Motors loading case is used to assess the current and voltage harmonic distortions. Proper system analysis is important when adding any new motor starting and controlling equipment. It will be able to better suggest the most appropriate starting and control method. Two medium voltage motors of air separation unit’ measurement results and simulations are summarized. Both current and voltage harmonic distortions are fitted linear regression model. The predicting THD values can be used for this kind of process for future planning.

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Marcel Didden1, Kurt Stockman2, William D’haeseleer3, Ronnie Belmans3
1)Laborelec, Belgium, 2) Hogeschool West-Vlaanderen, Belgium; 3) K.U.Leuven, Energy Institute, Belgium

Voltage sags can cause considerable financial damage in industrial processes containing variable speed drives. Many solutions exist to protect these sensitive processes, varying from modifications within the process itself to restructuring the supplying grid. In many cases, the only possibility to reduce the damage is to install mitigation equipment between the grid and the sensitive process such as an Uninterruptible Power Supply (UPS). However, protecting the entire process by a dynamic or static UPS often turns out to be too expensive. In the last decade, alternative mitigation methods have been developed that prevent most of the process outages at a much lower cost. This paper analyses these methods and shows how to choose the most cost effective one.

Janusz MINDYKOWSKI, Mariusz SZWEDA, Tomasz TARASIUK, Gdynia Maritime University, Poland

The paper is focused on a problem of electric power quality in ship electric power networks. Some current standards relevant to the discussed problem have been presented but the main part of the paper has described the research of voltage and frequency deviations on chosen ship. This research has been carried out on the ship owner request due to unusual steady-state frequency deviations from its rated value. Finally, the supply voltage parameters have been monitored during one exploitation trip and some conclusions for future undertakings have been drawn. This paper is based on original report for the ship owner and results of the research are given on the basis of the ship owner permission.

Tosak Thasananutariya 1, Somchai Chatratana 2, Mark McGranaghan 3, 1) Metropolitan Electricity Authority (MEA), Thailand 2) National Science and Technology Development Agency (NSTDA), Thailand 3) EPRI Solutions, United States

This paper proposes a practical method for economic evaluation of different alternatives to improve the performance of industrial facilities for voltage sags and momentary interruptions. Different technologies for solving voltage sag problems are discussed (both utility and customer solutions) and a procedure for evaluating the economics of the different alternatives is described. The concept of weighting factors to account for different levels of equipment sensitivity and customer costs as a function of the disturbance severity is introduced. This method allows for convenient evaluation of voltage sag impacts along with momentary interruption impacts. The economic analysis uses standard financial measures, such as the payback period, net present value (NPV), and internal rate of return (IRR) to assess the alternatives. The methodology is illustrated using a case study of voltage sag performance improvement alternatives at an industrial customer located in the Metropolitan Electricity Authority (MEA) service area.

Philip Keebler, Kermit Phipps, Bill Howe, EPRI Solutions, United States

Significant energy performance and power quality testing has been conducted on distributed resource (DR) technologies to determine energy efficiency and susceptibility and immunity to power line disturbances. However, comparatively little electromagnetic compatibility (EMC) testing has been conducted to address radiated and conducted emissions and immunity performance. DR technologies contain significant power electronic devices for the purposes of DR control and energy conversion. Such devices generate both radiated and conducted emissions into nearby environments where DR technologies may be installed, and are themselves susceptible to such emissions from the outside environment. This article will address the various types of emissions that various DR technologies can generate, and examine ways to reduce the levels of these emissions and enhance EMC immunity levels associated with DR technologies.

Antonio Moreno-Munoz

Voltage and current were measured at various laboratories; it was found that the main problems for the equipment installed were voltage sags, harmonics and leakage currents. The paper analyses the capabilities of modern power supplies; the convenience of embedded
solution is also discussed. Finally it is addressed the role of the Standards on the protection of electronic equipment and the implications for the final costumer.

Vyacheslav A. Tukhas, S.A. Eintrop, S.V. Pozhidaev,
Research and Production Company PRORYV-KE

Creation and realization the system of the technical monitoring and power quality
control in real time on the base of the new facility of the measurement power quality parameters
- an instrument "PRORYV-KE".

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