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Roman Sikora
Institute of Electrical Power Engineering, Lodz University of Technology, 90-924 Lodz, Poland

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Journal article
Published: 05 June 2020 in Energies
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Road lighting is an important element of road infrastructure influencing on the road safety. It helps road users to identify potential hazards on the road and reduces the risk of a road accident. Improving the energy efficacy of road lighting installations requires using new technologies. Currently, high-pressure sodium (HPS) lamps are still most commonly used in road lighting. Many of the luminaires with HPS lamps are still in good technical condition and there is no economic justification for replacing them (except improving energy efficacy). One of the methods of improving their energy efficacy is to replace the electromagnetic control gear (ECG) with an electronic ballast (EB). This replacement may affect the colorimetric parameters of the HPS lamps. Two methods to the estimation change of colorimetric parameters after the replacement of ECG to EB were used. The first is CIE TN 001:2014 and the second is ANSI/IES TM-30-15. The article also presents the advantages and disadvantages of these methods in relation to the evaluation of changes in colorimetric parameters of HPS lamps after the replacement of the ECG with an EB. After the replacement of ECG to EB, the smallest reduction of Ra (colour rendering index) occurred for the 150 W lamp by 31.30% and the highest reduction for the 70 W lamp by 65.52%. Considering the changes of the fidelity indicator Rf and gamut indicator Rg, their changes are significantly smaller than for Ra. The smallest change of Rf value was observed for a 150 W lamp (6.00%) and the largest for a 70 W lamp by 25.00%. In case of Rg, similar changes were observed—for 150 W lamp by 9.26% and for 70 W lamp by 21.88%. The ANSI/IES TM-30-15 method is more suitable for evaluating colorimetric parameters after replacing ECG with EB. Using only Ra to evaluate changes of HPS lamps colorimetric parameters after replacing the ballast type can lead to incorrect conclusions concerning changes of colorimetric parameters. Based on the ANSI/IES TM-30-15 method, it has been proposed to introduce the Δf,g indicator which determines the change of colorimetric parameters based on fidelity and gamut colour indicator.

ACS Style

Roman Sikora; Przemysław Markiewicz. Assessment of Colorimetric Parameters for HPS Lamp with Electromagnetic Control Gear and Electronic Ballast. Energies 2020, 13, 1 .

AMA Style

Roman Sikora, Przemysław Markiewicz. Assessment of Colorimetric Parameters for HPS Lamp with Electromagnetic Control Gear and Electronic Ballast. Energies. 2020; 13 (11):1.

Chicago/Turabian Style

Roman Sikora; Przemysław Markiewicz. 2020. "Assessment of Colorimetric Parameters for HPS Lamp with Electromagnetic Control Gear and Electronic Ballast." Energies 13, no. 11: 1.

Book chapter
Published: 25 March 2020 in Energy Efficiency and Sustainable Lighting - a Bet for the Future
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Improving the energy efficiency of road lighting is currently one of the most important issues. One of the methods of improving energy efficiency is the use of dimmable luminaires. In order to be able to compare the energy efficiency of different technical solutions, EN 13201-5 introduces energy performance indicators for road lighting installations. The chapter describes energy performance indicators for road installation and the impact of active power losses on these indicators and electricity costs. In order to accurately calculate the above indicators, the active power losses in the elements of the lighting installation should be taken into account. The chapter presents the dependencies which can be used to calculate the active power losses in single- and three-phase systems. In addition, an example of calculation of energy performance indicators, active power and energy losses and electricity costs is provided. The calculation was made for an exemplary installation of road lighting with dimmable luminaires. The analysis was done for single-phase and three-phase installations.

ACS Style

Roman Sikora; Przemysław Markiewicz. Energy Efficiency of the Road Lighting: The Impact of Active Power Losses on Energy Performance Indicators and Electricity Costs. Energy Efficiency and Sustainable Lighting - a Bet for the Future 2020, 1 .

AMA Style

Roman Sikora, Przemysław Markiewicz. Energy Efficiency of the Road Lighting: The Impact of Active Power Losses on Energy Performance Indicators and Electricity Costs. Energy Efficiency and Sustainable Lighting - a Bet for the Future. 2020; ():1.

Chicago/Turabian Style

Roman Sikora; Przemysław Markiewicz. 2020. "Energy Efficiency of the Road Lighting: The Impact of Active Power Losses on Energy Performance Indicators and Electricity Costs." Energy Efficiency and Sustainable Lighting - a Bet for the Future , no. : 1.

Journal article
Published: 21 March 2019 in Energies
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The paper presents the results of laboratory tests concerning the measurements of electrical parameters of road lighting luminaires. These measurements were focused on determining the dependence of the electrical parameters of the luminaires versus the changes of the RMS (Root Mean Square) value of the supply voltage and the level of disturbances in the supply voltage. The basic electrical parameters for light-emitting diode (LED) luminaires were analysed with the option of luminous flux adjustment if it existed. During the laboratory measurements, the luminaires were powered from the Agilent 6834B distorted voltage generator within the assumed acceptable range of the changes in the deformation level resulting from the applicable legal provisions for the reproduction of actual power supply conditions.

ACS Style

Roman Sikora; Przemysław Markiewicz. Analysis of Electric Power Quantities of Road LED Luminaires under Sinusoidal and Non-Sinusoidal Conditions. Energies 2019, 12, 1109 .

AMA Style

Roman Sikora, Przemysław Markiewicz. Analysis of Electric Power Quantities of Road LED Luminaires under Sinusoidal and Non-Sinusoidal Conditions. Energies. 2019; 12 (6):1109.

Chicago/Turabian Style

Roman Sikora; Przemysław Markiewicz. 2019. "Analysis of Electric Power Quantities of Road LED Luminaires under Sinusoidal and Non-Sinusoidal Conditions." Energies 12, no. 6: 1109.

Journal article
Published: 12 December 2018 in Sustainability
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In accordance with the requirements of PN EN 13201-5 standard for road lighting installation, energy performance indicators should be descripted. In order to calculate energy performance indicators, it is necessary to know the active power of the road lighting system. The above standard does not specify whether active power losses should be taken into account in calculations. The main purpose of the article is to estimate the active power losses in the road lighting installation. The article presents methods for calculating active power losses, taking into account losses in all main elements of the installation. The obtained calculation results show the relationship between active power losses and the power of luminaires, their number and spacing between poles. Calculations of active power losses were made for single-phase and three-phase installations. The active power losses in a three-phase system do not exceed 1.5% and in a single-phase installation they may be greater than 7%. Therefore, in order to obtain exact values of energy performance indicators (and also predict electricity consumption), active power losses should be taken into account in calculations. In addition, a comparative analysis of the effect of luminaires dimming and active power losses on annual CO2 emissions was made. Not taking into account the active power losses in the calculation of the lighting installation’s power, for single-phase installations in particular, understates the calculated value of CO2 emissions by more than 6%.

ACS Style

Roman Sikora; Przemysław Markiewicz; Wiesława Pabjańczyk. The Active Power Losses in the Road Lighting Installation with Dimmable LED Luminaires. Sustainability 2018, 10, 4742 .

AMA Style

Roman Sikora, Przemysław Markiewicz, Wiesława Pabjańczyk. The Active Power Losses in the Road Lighting Installation with Dimmable LED Luminaires. Sustainability. 2018; 10 (12):4742.

Chicago/Turabian Style

Roman Sikora; Przemysław Markiewicz; Wiesława Pabjańczyk. 2018. "The Active Power Losses in the Road Lighting Installation with Dimmable LED Luminaires." Sustainability 10, no. 12: 4742.

Journal article
Published: 29 May 2018 in Energies
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Before the use of regulated street luminaires with variable power and luminous flux, computations were performed using constant values for their electrical and photometric parameters. At present, where such lighting is in use, it is no longer possible to base calculations on such assumptions. Computations of energy and power losses, for example, need to be performed for all dimming levels and based on the applied regulation algorithm. Based on measurements carried out on regulated luminaires, it was found that certain electrical parameters have a nonlinear dependence on the dimming level. Electrical parameters were also observed to depend on the value of the supply voltage. The results of the measurements are presented in this article. Failure to take account of power losses in computations of the energy efficiency of street lighting in accordance with the applicable EN 13201 standard causes values of energy efficiency indicators to be overstated. Power loss computations are presented in this article for a sample street lighting system with regulated luminaires, for the whole range of dimming levels and additionally for fluctuations of ±10% in the supply voltage. In addition, a mathematical model of a regulated luminaire is constructed with the use of regression methods, and a practical application of that model is described.

ACS Style

Roman Sikora; Przemysław Markiewicz; Wiesława Pabjańczyk. Computing Active Power Losses Using a Mathematical Model of a Regulated Street Luminaire. Energies 2018, 11, 1386 .

AMA Style

Roman Sikora, Przemysław Markiewicz, Wiesława Pabjańczyk. Computing Active Power Losses Using a Mathematical Model of a Regulated Street Luminaire. Energies. 2018; 11 (6):1386.

Chicago/Turabian Style

Roman Sikora; Przemysław Markiewicz; Wiesława Pabjańczyk. 2018. "Computing Active Power Losses Using a Mathematical Model of a Regulated Street Luminaire." Energies 11, no. 6: 1386.

Case report
Published: 08 May 2018 in COMPEL - The international journal for computation and mathematics in electrical and electronic engineering
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Purpose 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. Design/methodology/approach 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. Findings As parameters that characterize short-time overcurrent at start-up are the maximum value of overcurrent amplitude in start-up moment (IPIC), the duration of overcurrent in start-up moment (tPIC) 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. Practical implications 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. Originality/value The study enables application of a probabilistic model for analysis of inrush currents of lighting luminaire and predicting the possible consequences of their occurrence.

ACS Style

Przemysław Markiewicz; Roman Sikora; Wieslawa Pabjanczyk. Statistical analysis of peak inrush current: a case study. COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 2018, 37, 1069 -1084.

AMA Style

Przemysław Markiewicz, Roman Sikora, Wieslawa Pabjanczyk. Statistical analysis of peak inrush current: a case study. COMPEL - The international journal for computation and mathematics in electrical and electronic engineering. 2018; 37 (3):1069-1084.

Chicago/Turabian Style

Przemysław Markiewicz; Roman Sikora; Wieslawa Pabjanczyk. 2018. "Statistical analysis of peak inrush current: a case study." COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 37, no. 3: 1069-1084.

Journal article
Published: 18 April 2018 in Open Physics
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The power systems usually include a number of nonlinear receivers. Nonlinear receivers are the source of disturbances generated to the power system in the form of higher harmonics. The level of these disturbances describes the total harmonic distortion coefficient THD. Its value depends on many factors. One of them are the deformation and change in RMS value of supply voltage. A modern LED luminaire is a nonlinear receiver as well. The paper presents the results of the analysis of the influence of change in RMS value of supply voltage and the level of dimming of the tested luminaire on the value of the current THD. The analysis was made using a mathematical model based on multivariable polynomial fitting.

ACS Style

Roman Sikora; Przemysław Markiewicz; Wiesława Pabjańczyk. Multivariable polynomial fitting of controlled single-phase nonlinear load of input current total harmonic distortion. Open Physics 2018, 16, 137 -142.

AMA Style

Roman Sikora, Przemysław Markiewicz, Wiesława Pabjańczyk. Multivariable polynomial fitting of controlled single-phase nonlinear load of input current total harmonic distortion. Open Physics. 2018; 16 (1):137-142.

Chicago/Turabian Style

Roman Sikora; Przemysław Markiewicz; Wiesława Pabjańczyk. 2018. "Multivariable polynomial fitting of controlled single-phase nonlinear load of input current total harmonic distortion." Open Physics 16, no. 1: 137-142.

Conference paper
Published: 01 September 2017 in 2017 18th International Symposium on Electromagnetic Fields in Mechatronics, Electrical and Electronic Engineering (ISEF) Book of Abstracts
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Electrical equipment with nonlinear current-voltage characteristics are the source of numerous unfavorable phenomena in power supply networks. One such phenomenon is the harmonic current disturbance, the level of which is characterized by a total harmonic distortion THD I . The value of the THD I depends on many factors, primarily the construction, the principle of operation of the equipment and the degree of the distortion of the supply voltage. One of the typical nonlinear equipment is a LED luminaire with an impulse power supply for adjusting the power and illumination of the luminaire. The paper presents the laboratory results of studies on the influence of the supply voltage and the level control of the luminaire on the value of the THD I .

ACS Style

Roman Sikora; Przemyslaw Markiewicz; Wieslawa Pabjanczyk. Surface polynomial fitting of controlled single-phase nonlinear load of input current total harmonic distortion. 2017 18th International Symposium on Electromagnetic Fields in Mechatronics, Electrical and Electronic Engineering (ISEF) Book of Abstracts 2017, 1 -2.

AMA Style

Roman Sikora, Przemyslaw Markiewicz, Wieslawa Pabjanczyk. Surface polynomial fitting of controlled single-phase nonlinear load of input current total harmonic distortion. 2017 18th International Symposium on Electromagnetic Fields in Mechatronics, Electrical and Electronic Engineering (ISEF) Book of Abstracts. 2017; ():1-2.

Chicago/Turabian Style

Roman Sikora; Przemyslaw Markiewicz; Wieslawa Pabjanczyk. 2017. "Surface polynomial fitting of controlled single-phase nonlinear load of input current total harmonic distortion." 2017 18th International Symposium on Electromagnetic Fields in Mechatronics, Electrical and Electronic Engineering (ISEF) Book of Abstracts , no. : 1-2.