Peter Janiga

A new methodology for failure identifying in public lighting network by smart metering

The aim of this paper is describe the application of smart metering technologies in public lighting networks in order to reduce the cost associated with operation and maintenance. Smart metering technology is rapidly developing technology now. In some countries are applications of smart metering already. In Slovakia smart metering is prepared to operation. In paper are described examples of smart metering technology in context of public lighting operation. For specific examples are described methodology of faults identifying by smart metering. The proposed methodology creates a new path in operation of public lighting networks.

Automated system of the measurement of electric parameters of luminaires and light sources at chosen operational conditions

Quality of electric power is influenced all supplied devices. Due to changes supply voltage are electric parameters what can influence their other features. Therefore for example luminaires are measured at different supply voltage to find out impact of supply voltage to the luminous flux. This paper concerns system of analysis at change of supply voltage on photometric parameters of luminaires. Designed system is appropriate for measurement of electric parameters of luminaires because for them description their behaviour at various level of supply voltage is complicated.

Research on Smart Home Energy Management System

Europe is committed to the 20-20-20 targets to reduce carbon emissions and to secure energy supply. Energy efficiency and renewable energy are seen as key to reach these goals. Both measures all for changes in our energy supply system leading to smart grids for the required innovation. The fundamental architecture of networks build in years ago has been developed in most member states to meet the needs of large, predominantly carbon-based generation technologies. But now the networks will have to integrate decentralized and renewable power generation, also with many small suppliers. More flexible transport of power is needed in response to new energy markets and energy trading, and to the trend towards location of bulk generation far from load. The European Commission has taken a number of actions including a mandate on standardization for smart grids issued in 2011. The final customer with small source has a potential to participate on smart grid features and thus should be involved and motivated throughout several motivation stimulus. One of the key features in the smart grid applications is the demand side service offered to designated parties by smart home automation systems. This paper describes the base of home automation systems upon the smart grid reference architecture. The paper also describes the fundamentals on research of Smart Home Energy Management System and demonstrates the idea of its utilization for demand side management on simulation experiment of low voltage grid with distributed sources.

Testing system for smart meters

Smart metering issue is currently high on topic. Continual requests for results of testing and functionality verification lead to the creation of automatic testing system. In this system are connected programmable source, measuring device and created application. It is comprehensive analysis tool. Last version of this tool can work in testing or automatic mode. The second mode is for repeated tests and it can work fully autonomous. Paper describes created system for testing of smart meters and related devices according to specified parameters. Testing system is used for laboratory measuring and testing of electrical parameters of smart meters and also for testing communication between smart meter and other points of smart metering data network.

Verification of steady state model of power autotransformer

This paper deals with the model of three-winding autotransformer for steady state analyses and for different types of step-voltage regulator. The paper is focused on comparison of two types of three winding transformer model and on verification of these models by means of measurement of distributing transformer. The analyzed transformer is installed and operated in the electric power station Stupava.

Comparison of Reconfigurations Using Deterministic Approach for Global Assessment of Operational State in Power System

This article deals with the analysis of impact reconfiguration on the power system operational state. The stated analysis assess results of the simulated calculations of N-1 events with the aim to obtain a more complex view of the security criterion N-1 use in comparison with the current methods and procedures being in practice. Methodologies based on the deterministic approach arising from calculations of steady states with the global assessment of the power system operational states are presented. The article objective is to comprehensively compare the selected operational states especially different reconfiguration variants in a power system.

Change of the spectral power distribution of luminaires under various electrical conditions

In general spectroradiometric measurements are very important part of characterisation of photometric or colorimetric parameters of luminaires. Street luminaires are installed in the outdoor conditions and can be operated under various electrical conditions depending on quality of the electric power. Electrical parameters may not always be ideal. Some disturbances in the electricity grid can occur. These disturbances can negatively influence output even photometric or colorimetric parameters of these luminaires. Investigated parameter in both cases is spectrum of luminaire. In paper is investigated influence of simulated of various supplied electrical conditions on some type of street luminaires. Especially the most effort is focused on spectral changes of output luminaires supplied with artificially simulation by stabilized of power supply. Presented results discuss extent of effect on described parameters above.

Distributed generation and its influence on voltage changes in low voltage grids and transformer loading

The installed power in distributed generation sources is growing and we record recently more of domestic consumers equipped with the small sources, that operates in low voltage grids. The conception of power supply process is changing from the central production to the decentralization of electricity production. Despite the advantages of distributed generation, the utilities in energy sector have to face also the technical problems that are coming with it. The power system was build to produce the energy in central power plants, to transfer and to distribute it thru long distances to the consumption places in low or medium voltage grids. Radial connection of 22kV power grids, transformers without the remote control of tape changes, harmonics, etc. are the technical barriers for distributed generation. Each source has to meet the technical condition for connection of source to the grid, that are usually set by the relevant distribution system operator. One of the most important condition is the requirement for steady state voltage change. This paper is focused on the analysis of the distribution generation according to the voltage changes in steady state operation and the transformer loading.

Energy performance numerical indicators of public lighting

Energy performance assessment for lighting systems is recognized as an important tool for promotion of energy efficient lighting technologies. Based on European directives, components of lighting systems are subjected to eco-design requirements, and lighting systems in buildings are evaluated for energy performance. Now, similar activities are running in the field of public lighting. This paper brings a brief state-of-the art in the standardization process and aims to inform about partial research studies which have to contribute to the preparation of a new European standard.

Power Quality in Public Lighting Installations

Power quality in public lighting networks is yet not sufficiently studied today. New conditions and requirements arise as a consequence of rapid application of new technologies like LED lighting, lighting control and monitoring, adaptive lighting systems etc. Optimization of reliable and efficient service of public lighting systems can be only achieved if behaviour of individual elements within the system are well described. For erection, operation and re-construction of public lighting networks it is important to have knowledge on behaviour of the network in different conditions. Because currents primarily depend on the supply voltage, it is essential to analyze electrical parameters not only under standard conditions but also under operational conditions. These comprise e.g. distorted or regulated voltage supply. Non-linearity of electrical parameters of luminaires seems to have significant influence on power quality. In luminaires with conventional ballast, non-linearity is generated by discharge lamp as well as choke. The older type of lamp or choke (in aged existing systems), the worse characteristics. Luminaires with electronic ballasts do not provide this effect and are helpful to maintain “clear” networks. However, in the field of public lighting, unlike in interior lighting with fluorescent lamps for instance, electronic control gears still do not reach any comparative popularity. LED luminaires of diverse quality now intrude the market though technology level, as agreed by experts on many forums, do not compete with available traditional lighting approaches, is known for unsolved problems and needs a series of further developments. From the electrical point-of-view, control gears for LED lamps are similar to electronic ballasts. Supply voltage provided by switch-type source is rectified first. Semiconductor components of rectifier act as non-linear elements. Though these control gears have to be equipped with filter of harmonics, many LED luminaires still lack such circuits. For assessment and investigation of power quality characteristics it is indispensable to understand the behaviour of individual elements and then the behaviour of network as a whole. Distribution network impacts the public lighting network (via transformer) and vice versa. To describe the nature of this two-way influence in details is very complicated, thus certain simplifications in order to speed up calculations are applied. For example, nominal values of harmonic voltages or currents can be used instead of distorted (non-harmonic) characteristics. Or for accurate calculation of steady-state network with discharge lamps measured values can be used instead of complicated description of discharge parameters.