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The purpose of this paper is to address the issue of power quality through a case study in an IT‐intensive modern office building.

This paper presents results from a power quality audit conducted last year. Firstly, the power site inspection included: (a) a walk‐down of the facility's electrical system to inspect the condition of equipment and becoming familiar with the electrical system; (b) interviewing facility electrical personnel and end‐users on failure of equipment; (c) identifying and collecting the electronic equipment that is most sensitive to power disturbances; (d) requesting and reviewing equipment literature and electromagnetic compatibility characteristics; (e) after that, in the power quality monitoring, voltage and current were measured at various floors.

It was found that the main problems for the equipment installed were harmonics and leakage currents. The paper examines the causes and effects of power disturbances that affect computer or any other microprocessor based equipment and analyses the disadvantages of modern power supplies.

This provides useful information for facilities managers on the current state of power disturbances. The convenience of “enhanced power supply” is also discussed. Finally, it is addressed the role of standards on the protection of IT and the implications for the final costumer.

This paper has provided empirical data from a power site survey developed in a high tech building. This case study demonstrates the impacts of generalized electronic devices on the power quality of the buildings and the implications on energy uses.

The purpose of this paper is to estimate that the start-up current parameters are stochastic or not. Electronic equipment in luminaries significantly improves their luminous efficiency, thereby increasing the energy efficiency of lighting installations. However, the use of electronics [e.g. electronic ballasts for discharge lamps or power supply units for light-emitting diode (LED) luminaries] may also cause some negative effects in lighting installations. One of such effects is large inrush current, which can greatly exceed the admissible line load and trigger the overcurrent protective devices.

The paper presents results of laboratory tests together with their statistical analysis of the inrush currents of lighting luminaires. Three road luminaires build in different technologies of similar power have been selected for the study. The theoretical distributions described by the analytical formulas matched the empirical distributions by using the MATLAB’ Statistical Toolbox.

As parameters that characterize short-time overcurrent at start-up are the maximum value of overcurrent amplitude in start-up moment (I_PIC), the duration of overcurrent in start-up moment (t_PIC) and melting integral MI. The aim of this statistical analysis of the selected parameter is to provide an overcurrent mathematical description allowing to estimate the probability of occurrence of values. For lighting luminaire fitted with magnetic ballasts, the parameters analyzed will randomly vary with the moment of power on. For electronic ballasts, the occurrence of this phenomenon depends on the adopted construction solution.

This will allow, for example, to estimate the probability of activation of protection device by comparing the value of the inrush current Joule’s integral MI with its value for the analyzed protection device. The proposed method may be useful for checking the selectivity of the protection devices in the lighting system.

The study enables application of a probabilistic model for analysis of inrush currents of lighting luminaire and predicting the possible consequences of their occurrence.

The paper aims to present a learning environment for optimal synthesis of voltage regulator circuits (LEOS‐VRC) using PSPICE simulator.

LEOS‐VRC supports a database with voltage regulator circuits edited as projects in PSPICE compatible format and a methodology for optimal synthesis. The methodology is based on the estimation of multiple voltage regulator circuits' realizations over a given specification, through comparative study in PSPICE, using a set of predefined specific electrical characteristics, which values are determined from simulation waveforms. LEOS‐VRC allows integrating the voltage regulator circuit in a power supply system through adding transformer, rectifier and control stages. Both linear and switch‐mode power supplies are considered.

The methodology and examples proposed illustrate the efficiency of LEOS‐VRC for teaching and self‐education in the area of power supply circuit design.

In future LEOS‐VRC database will be enlarged with new voltage regulator circuit topologies and new controller circuits.

LEOS‐VRC is suitable for students in electronics and designers of power supply circuits.

With LEOS‐VRC students become familiar with multisolution synthesis. By analyzing the complex behaviour of the power supply system and applying comparative study and optimization criteria, they can make a motivated selection of an optimal voltage regulator design solution for a concrete application.

Messerschmitt‐Bölkow‐Blohm, Germany's biggest aerospace company, is presenting sections of its wide range activities at Farnborough. As befits its corporate policy — typical examples may also be seen on the stands and in the outdoor displays of the companies in whose programmes MBB has an essential share in its capacity as shareholder or partner:

The purpose of this paper is to provide a new theory of adjustable speed decoupled generation which has the potential to challenge existing coupled generation based on a classical synchronous generator operating with fixed speed.

The paper's approach is a theoretical consideration of the drawbacks of conventional fixed speed generation based on a synchronous generator and proposal of problem solutions by the introduction of a decoupled generation system with additional degree of freedom. Computer calculations are used as design and for preliminary verification. Tests in a real laboratory system equipped with modern components such as electrical machines and power electronic converters proved the theory.

Decoupled generation is realized in a very original way using new blocks, integration method and control. The developed system has been awarded more than six world patents. The system has additional degrees of freedom in speed and grid connection operation.

The research team has concentrated its research over many years and developed a generation system which has been awarded a great number of patents. A special axial flux, light and simple permanent magnet generator was developed and integrated to the prime mover. A three‐phase AC/AC power electronic converter and a DSP controller are integrated to a very small size and low weight. The invented topology provides a very reliable operation, high‐quality AC voltage in fully three‐phase non‐symmetrical load. There were also presentations on world conferences (EPE, PESC, EPE‐PEMC).

This paper aims to present the prototype of a 140 kVA shunt active power filter (APF) for current harmonics and fundamental reactive power compensation of a 200 kW induction heating system.

Design issues of the power components, of the switching ripple filter and of the digital control are addressed and discussed. The APF control algorithm has been implemented on the 16‐bit, fixed‐point, TMS320LF2407 A DSP controller. The current control is based on proportional‐sinusoidal signal integrators with good performance in current harmonic elimination and power factor compensation.

The experimental tests, performed in real industrial environment for a 200 kW induction heating plant, show that the performance goals are fulfilled.

The sinusoidal signal integrators (for consistency with the other plural forms of acronyms) of the current controller are implemented in the rotating reference frame aligned with the voltage vector at the point of common connection. This allows the compensation of two harmonics with a single SSI, thus halving the computational effort of the DSP.

In industrial induction heating, the need for harmonic and reactive power compensation lasts a few seconds per minute, making passive solutions not suitable. The presented APF is a valid solution for this application, where only a few tailored implementations are available on the market.

Present 3D electromagnetic simulators have high accuracy, but they are time and memory expensive. Because of that, fast and simple expression for impedance is also necessary for initial inductor design. In this paper new efficient method for total impedance calculation of ferrite electromagnetic interference (EMI) suppressor is given. By using an algorithm, it is possible to predict correctly all variations of electrical characteristics introduced by varying geometry parameters of EMI suppressor.

The starting point for calculation of electrical characteristics of EMI suppressor is Greenhouse theory. Greenhouse decomposed inductor into its constituent segments. Basically, all segments of conductive layer are divided into parallel filaments having small, rectangular cross sections. The self‐ and mutual‐inductance were calculated using the concept of partial inductance. Total impedance of EMI suppressor is calculated taking care of dimension of chip size, material that are used and geometry of conductive layer.

The Simulator for Planar Inductive Structures (SPIS™) simulates effects of ferrite materials and geometrical parameters of planar inductive structures. With proposed software tool, designers can predict performance parameters quickly and easily before costly prototypes are built. SPIS™ software offers substantially reduced time to market, and increases device performance. The computed impedances, given by our software tool are compared with measured data and very good agreement was found.

Applied flexible efficient methods for impedance calculation of EMI suppressor are able to significantly increase the speed design of multilayer suppressors for universal series bus, low‐voltage differential signaling and in other high‐speed digital interfaces incorporated in notebooks and personal computers, digital cameras and scanners. Also, ferrite suppressors have been successfully employed for attenuating EMI in switching power supplies, electronic ignition systems, garage door openers, etc.

The paper presents realized structures of ferrite EMI suppressors. New geometries of conductive layer are proposed. In addition, using simple model of inductor, the paper develops a CAD simulation tool SPIS™ for calculation of electrical characteristics of EMI suppressors with different geometry of conductive layer.

The purpose of this paper is to introduce a unique multilevel, one‐phase inverter (in the multiplied full‐bridge configuration, cascaded‐type) with unequal voltage distribution among the voltage levels.

Numerical and experimental results are discussed and the topology thereafter evaluated.

Unequal voltage distribution among voltage stages of the converter leads to increase of the output voltage resolution while simplifying the converter construction and minimizing the power switch losses. Simplorer numerical analyses as well as test stand measurements were led in order to verify properties of the system. Using the voltage distribution in the proportion of 6/2/1 leads to improved utilisation of power switches used in the means of voltage, current and switching frequency. FFT analysis was implemented in order to explore the frequency domain properties of the control apparatus.

The results allow improvement of power switch utilisation and output voltage resolution of cascaded, three‐stage multilevel converter topologies and voltage output filter optimisation for multilevel power electronic converters.

A new concept of voltage distribution is provided and described, a dedicated DSP‐based control system was developed as well as a small‐scale converter prototype, test stand measurement results are provided.

This study aims to examine the effects of trading partner trust and trading partner power, on supply chain integration, and their impact on business performance in the context of Web-enabled supply chains. In doing so, the authors extend previous studies by exploring this phenomenon by using an integrative theory-driven approach.

This study presents a theoretical model grounded on the resource-based and dynamic capabilities views and the social capital theory. Data collected from 175 firms in the USA are used to test the hypotheses using structural equation modeling.

Results highlight the importance of trust and supply chain integration on business performance, whereas power did not appear to have an effect on supply chain integration in Web-enabled supply chains. The findings are robust to concerns of endogeneity, common method bias and alternative model specification.

Companies engaged in Web-enabled supply chains need to focus on increasing their integration efforts, and these efforts must also be accompanied by partnerships built on trust. Trading partners who might be inclined to use coercive strategies to influence other members of the supply chain in Web-enabled environments may be better off using cooperative approaches based on trust to achieve their desired goals.

This study integrates the resource-based view, dynamic capabilities view and the social capital theory to explore the dynamic relationships between trading partner trust, trading partner power and supply chain integration in Web-enabled supply chains. In doing so, this paper extends prior studies by examining supply chain integration’s impact on business performance and its mediating role, as it relates to trading partner trust and power in Web-enabled supply chains.

This paper discusses evidence from field studies undertaken to investigate the responsiveness of the order fulfilment process in a number of companies. The evidence is analysed in the context of the literature on responsiveness and related areas such as time‐based competition. Similarities and differences are analysed across a number of industrial sectors with respect to order fulfilment processes and the interpretation and significance of responsiveness. Generic factors that influence different types of companies are identified. Four components of responsiveness – stimuli, awareness, capabilities and goals – emerge from an analysis of the literature. The field and case study evidence allows the development of more precise definitions and descriptions of each of these components. The study also allows a generic responsiveness framework to be developed that incorporates both strategic and operational viewpoints. The need for more field studies on responsiveness is noted. More work is advocated on the assessment and measurement of responsiveness and on developing appropriate responsiveness interventions, particularly with respect to the order fulfilment process.