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Ravindran, V., Sakar, S., Rönnberg, S. & Bollen, M. (2020). Characterization of the impact of PV and EV induced voltage variations on LED lamps in a low voltage installation. Electric power systems research, 185, Article ID 106352.
Open this publication in new window or tab >>Characterization of the impact of PV and EV induced voltage variations on LED lamps in a low voltage installation
2020 (English)In: Electric power systems research, ISSN 0378-7796, E-ISSN 1873-2046, Vol. 185, article id 106352Article in journal (Refereed) Published
Abstract [en]

Photovoltaic (PV) systems, Electric vehicles (EV) and LED lamps have gained significant popularity in our current society. It is therefore common to find customer installations with all three operating together. PV and EV are known sources of voltage variations on the grid. The impact of these voltage variations on LED lamps situated in close proximity to PV or EV in a low voltage installation, in terms of overvoltage, undervoltage, and rapid voltage changes is systematically studied in a laboratory environment in this paper. Such variations can cause malfunctioning of the lamp based on its immunity and tolerance level or be disturbing to the end-user based on the intensity of variations and rate of recurrence of being subjected to such variations. In this work, the observed impacts on LED lamps are illustrated as 15 different cases. The scope of this work is to identify the possible impacts due to voltage variations induced by PV and EV systems on LED lamps and the potential problems that could happen long term due to recurrent subjection of such voltage variations.

Place, publisher, year, edition, pages
Elsevier, 2020
Keywords
Electric vehicle, LED lamps, Light emitting diodes, Photovoltaic systems, Harmonic analysis, Power quality, Voltage variations
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Electric Power Engineering
Identifiers
urn:nbn:se:ltu:diva-78984 (URN)10.1016/j.epsr.2020.106352 (DOI)
Note

Validerad;2020;Nivå 2;2020-05-26 (johcin)

Available from: 2020-05-26 Created: 2020-05-26 Last updated: 2020-05-26Bibliographically approved
Sakar, S., Bagheri, A., Rönnberg, S. & Bollen, M. (2020). Susceptibility of LED street lamps to voltage dips. Lighting Research and Technology
Open this publication in new window or tab >>Susceptibility of LED street lamps to voltage dips
2020 (English)In: Lighting Research and Technology, ISSN 1477-1535, E-ISSN 1477-0938Article in journal (Refereed) Epub ahead of print
Abstract [en]

There is an ongoing transition from high-pressure sodium lamps to LED street lamps that offer higher efficiency, cost saving and better photometric performance. This transition could lead to unintended consequences such as light flicker and extinguishing in street lighting applications when they are exposed to voltage dips. The goal of this paper is to analyse the light intensity variation of various street lamps when they are exposed to voltage dips. Several performance metrics for quantifying immunity of lamps have been proposed. Values for these metrics are obtained by applying artificial voltage dips to lamps. For voltage dips with residual voltage above 38%, lamps are immune in terms of a short-term light flicker metric. For residual voltage above 25%, light intensity reduces but without extinguishing. Compared to an incandescent lamp and high-pressure sodium lamp, LED street lamps exhibit longer zero-light intensity duration. Most of the studied LED street lamps exhibit uncoordinated light intensity drops, i.e. longer or shifted, with respect to the applied voltage dip. Individual characteristics of LED street lamps require testing before installation to prevent unexpected consequences. Recommendations are given for standardisation committees to implement an assessment method for lighting equipment.

Place, publisher, year, edition, pages
Sage Publications, 2020
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Electric Power Engineering
Identifiers
urn:nbn:se:ltu:diva-78574 (URN)10.1177/1477153520917441 (DOI)000527112000001 ()2-s2.0-85083804320 (Scopus ID)
Available from: 2020-04-20 Created: 2020-04-20 Last updated: 2020-05-08
Sakar, S., Rönnberg, S. & Bollen, M. (2019). Interferences in AC-DC LED Drivers Exposed to Voltage Disturbances in the Frequency Range 2 kHz - 150 kHz. IEEE transactions on power electronics, 34(11), 11171-11181
Open this publication in new window or tab >>Interferences in AC-DC LED Drivers Exposed to Voltage Disturbances in the Frequency Range 2 kHz - 150 kHz
2019 (English)In: IEEE transactions on power electronics, ISSN 0885-8993, E-ISSN 1941-0107, Vol. 34, no 11, p. 11171-11181Article in journal (Refereed) Published
Abstract [en]

LED lamps are both potential victims and sources of electromagnetic disturbances in the frequency range between 2 kHz and 150 kHz (“supraharmonics”). Immunity tests for this frequency range are important due to possible performance degradation of light intensity with LED lamps. In this paper, the impact of supraharmonics (SHs) on light intensity from LED lamps has been analyzed. LED lamps have been exposed to supraharmonic test profiles based on IEC 61000-4-19. Three phenomena that impact light intensity metrics have been observed and explained by models: (1) earlier conduction/later blocking caused by supraharmonic voltage, (2) intermittent conduction depending on the supraharmonic impedance of the LED driver and (3) reverse-recovery current of the diodes at higher frequency. It is observed that impact on the light intensity metrics shows up around the beginning and end of the conduction period. The results reveal that the profile of the supraharmonic voltage could cause deviations in the modulation depth and the average light intensity. The immunity of LED lamps against SHs shall be further studied and discussed by research groups and standard committees.

Place, publisher, year, edition, pages
IEEE, 2019
Keywords
AC-DC power converters, Electromagnetic compatibility, immunity testing, LED lamps, Lighting, Power-system harmonics, Power quality, Supraharmonics, Switching converters
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Electric Power Engineering
Identifiers
urn:nbn:se:ltu:diva-73679 (URN)10.1109/TPEL.2019.2899176 (DOI)000485746400069 ()2-s2.0-85072195162 (Scopus ID)
Funder
Swedish Energy Agency
Note

Validerad;2019;Nivå 2;2019-09-23 (johcin)

Available from: 2019-04-16 Created: 2019-04-16 Last updated: 2019-10-04Bibliographically approved
Sakar, S., Rönnberg, S. & Bollen, M. (2019). Light intensity immunity performance of LED street lamps under power quality disturbances. In: : . Paper presented at CIRED 2019 Conference.
Open this publication in new window or tab >>Light intensity immunity performance of LED street lamps under power quality disturbances
2019 (English)Conference paper, Published paper (Refereed)
Abstract [en]

An increasing application of LED street lamps brings out an important question regarding their immunity against power quality disturbances. The behaviour of commonly used lighting equipment such as incandescent lamps, compact fluorescent lamps (CFL), and gas-discharge lamps is known. However, knowledge on immunity of LED based lighting equipment is still limited, particularly in street lighting aspect. In this paper, immunity of LED street lamps is determined for voltage dips, short interruptions, voltage fluctuations and supraharmonics. A series of experiments has been performed with respect to test levels defined in IEC 61000-4-11, IEC 61000-4-15 and IEC 61000-4-19. Voltage dips and short interruptions cause higher short-term light flicker severity values that might lead to unintended consequences for car drivers and pedestrians. Interharmonics can result in light flicker, but the impact is very limited, only one lamp exceeds the limits. Supraharmonics impact the current but have minor impact on the visible light. The supraharmonic current can be 25 times nominal. This could decrease the lifetime of equipment

Keywords
street lamps, LED lamps, voltage disturbance
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:ltu:diva-76485 (URN)
Conference
CIRED 2019 Conference
Available from: 2019-10-23 Created: 2019-10-23 Last updated: 2019-10-23
Sakar, S., Rönnberg, S. & Bollen, M. (2018). Immunity Test of LED Lamps Based on IEC 61000-4-19 and Unexpected Consequence. In: Proceedings of International Conference on Harmonics and Quality of Power, ICHQP: . Paper presented at 18th International Conference on Harmonics and Quality of Power (ICHQP 2018), Ljubljana, Slovenia, May 13–16 2018. Piscataway, NJ: Institute of Electrical and Electronics Engineers (IEEE)
Open this publication in new window or tab >>Immunity Test of LED Lamps Based on IEC 61000-4-19 and Unexpected Consequence
2018 (English)In: Proceedings of International Conference on Harmonics and Quality of Power, ICHQP, Piscataway, NJ: Institute of Electrical and Electronics Engineers (IEEE), 2018Conference paper, Published paper (Refereed)
Abstract [en]

ED lighting technology is the most efficient way oflighting service and its usage has increased rapidly. Although,LED lamps are potential victim and source of electromagneticinterference in the frequency range between 2 kHz and 150 kHz(“supraharmonics”). Therefore, immunity test for this frequencyrange is necessary to analyze its performance variations. In thisstudy, Test profiles described in IEC 61000-4-19 have beenapplied to LED lamps and the results have been analyzedaccording to implemented algorithm that uses the relative lightintensity variation index. The results show that bothsupraharmonics and modulation of the test profiles can reveallight flicker. In addition, some potential drawbacks of thestandard have been found that deviation of the mains’ frequencyis also another factor causes intermodulation/nonsynchronizationon the applied test signal, so this can be seen aslight flicker. This issue better be clarified with more details in theIEC 61000-4-19, particalulary for lighting equipment.

Place, publisher, year, edition, pages
Piscataway, NJ: Institute of Electrical and Electronics Engineers (IEEE), 2018
Series
International Conference on Harmonics and Quality of Power, E-ISSN 1540-6008
Keywords
LED lamps, immunity, IEC 61000-4-19, flicker, supraharmonics
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Electric Power Engineering
Identifiers
urn:nbn:se:ltu:diva-68921 (URN)10.1109/ICHQP.2018.8378853 (DOI)2-s2.0-85049258911 (Scopus ID)9781538605172 (ISBN)
Conference
18th International Conference on Harmonics and Quality of Power (ICHQP 2018), Ljubljana, Slovenia, May 13–16 2018
Available from: 2018-05-27 Created: 2018-05-27 Last updated: 2018-08-08Bibliographically approved
Sakar, S., Balci, M. E., Abdel Aleem, S. H. .. & Zobaa, A. F. (2018). Integration of large- scale PV plants in non-sinusoidal environments: Considerations on hosting capacity and harmonic distortion limits. Renewable & sustainable energy reviews, 82(1), 176-186
Open this publication in new window or tab >>Integration of large- scale PV plants in non-sinusoidal environments: Considerations on hosting capacity and harmonic distortion limits
2018 (English)In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 82, no 1, p. 176-186Article in journal (Refereed) Published
Abstract [en]

Distributed generation (DG) penetration in a system may affect power quality, and energy efficiency, if it exceeds a particular value, known as the system's hosting capacity (HC). In this work, a comprehensive overview of hosting capacity and harmonic distortion limits is presented and discussed. The highest allowable penetration level of photovoltaic (PV)-based distributed generation units, hosted on typical industrial distribution systems, was analyzed in terms of the three power quality and energy efficiency performance parameters, namely bus voltage limits, line ampacities, and harmonic distortion limits. The analytical results show that the system's HC decreases with increase in utility side's background voltage distortion and load side's nonlinearity values. The HC level was affected more by the nonlinearity of the load side than by the utility side's background voltage distortion. Therefore, a single-tuned passive filter is suggested for maximizing the system's limited HC. Further, an optimization algorithm was developed to find simultaneously the system's HC and the parameters of the proposed filter, by considering the three performance parameters as constraints. The proposed filter design was found to attain a better level of HC than what can be obtained with a traditional filter design, based on current demand distortion minimization.

Place, publisher, year, edition, pages
Elsevier, 2018
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Electric Power Engineering
Identifiers
urn:nbn:se:ltu:diva-65828 (URN)10.1016/j.rser.2017.09.028 (DOI)000417079400013 ()2-s2.0-85029510171 (Scopus ID)
Note

Validerad;2017;Nivå 2;2017-09-26 (andbra)

Available from: 2017-09-26 Created: 2017-09-26 Last updated: 2018-05-04Bibliographically approved
Sakar, S., Rönnberg, S. & Bollen, M. (2018). Light Intensity Behavior of LED Lamps within theThermal Stabilization Period. In: Proceedings of International Conference on Harmonics and Quality of Power, ICHQP: . Paper presented at 18th International Conference on Harmonics and Quality of Power (ICHQP 2018), Ljubljana, Slovenia, May 13–16 2018. Piscataway, NJ: Institute of Electrical and Electronics Engineers (IEEE)
Open this publication in new window or tab >>Light Intensity Behavior of LED Lamps within theThermal Stabilization Period
2018 (English)In: Proceedings of International Conference on Harmonics and Quality of Power, ICHQP, Piscataway, NJ: Institute of Electrical and Electronics Engineers (IEEE), 2018Conference paper, Published paper (Refereed)
Abstract [en]

Visible changes in the light intensity of lamps, referredto as flicker, are quantified based on definitions such asnormalized gain factor and relative light intensity variation.However, those values also change depending on the time after anLED lamp has been switched on. An experiment has been carriedout to analyze this phenomenon. A new metric, a “thermalstabilization time”, has been proposed to identify the time toreach steady state light intensity. Although rare, the change inlight intensity can reach up to 68% during the thermalstabilization time. Consequently, acquiring data at differentintervals can lead to incorrect estimation of critical metrics.Stabilization is an essential factor that should be taken intoconsideration in LED lamps’ measurement. It is recommended bythe authors that 60-minute operation is required before acquiring data.

Place, publisher, year, edition, pages
Piscataway, NJ: Institute of Electrical and Electronics Engineers (IEEE), 2018
Series
International Conference on Harmonics and Quality of Power, E-ISSN 1540-6008
Keywords
LED lamps, lighting, power quality, thermal stability, voltage fluctuations
National Category
Electrical Engineering, Electronic Engineering, Information Engineering Other Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Electric Power Engineering
Identifiers
urn:nbn:se:ltu:diva-68920 (URN)10.1109/ICHQP.2018.8378917 (DOI)000444771900106 ()2-s2.0-85049245726 (Scopus ID)9781538605172 (ISBN)
Conference
18th International Conference on Harmonics and Quality of Power (ICHQP 2018), Ljubljana, Slovenia, May 13–16 2018
Available from: 2018-05-27 Created: 2018-05-27 Last updated: 2018-10-10Bibliographically approved
Sakar, S., Balci, M. E., Abdel Aleem, S. H. .. & Zobaa, A. F. (2017). Increasing PV hosting capacity in distorted distribution systems using passive harmonic filtering. Electric power systems research, 148, 74-86
Open this publication in new window or tab >>Increasing PV hosting capacity in distorted distribution systems using passive harmonic filtering
2017 (English)In: Electric power systems research, ISSN 0378-7796, E-ISSN 1873-2046, Vol. 148, p. 74-86Article in journal (Refereed) Published
Abstract [en]

Adding new capacity expansion alternatives using distributed generation (DG) technologies, particularly penetration of renewable energy, has several economical, and technical advantages such as the reduced system costs, the improved voltage profile, lower line loss and enhanced system’s reliability. However, the DG units may lead to power quality, energy efficiency, and protection problems in the system when their penetration exceeds a particular value, generally called as the system’s hosting capacity (HC) in the literature. In this paper, the HC determination of a distorted distribution system with Photovoltaic (PV)-based DG units is handled as an optimization problem by considering over and under voltage limitations of buses, current carrying capabilities of the lines, and harmonic distortion limitations as constraints. It is seen from simulation results that the HC is dramatically decreased with the increment of the load’s nonlinearity level and the utility side’s background voltage distortion. Accordingly, a C-type passive filter is designed to maximize the harmonic-constrained HC of the studied system while satisfying the constraints. The results indicate that higher HC level can be achieved using the proposed filter design approach compared to three conventional filter design approaches as voltage total harmonic distortion minimization, line loss minimization and power factor maximization.

Place, publisher, year, edition, pages
Elsevier, 2017
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Electric Power Engineering
Identifiers
urn:nbn:se:ltu:diva-62940 (URN)10.1016/j.epsr.2017.03.020 (DOI)000402446800008 ()2-s2.0-85016451814 (Scopus ID)
Note

Validerad; 2017; Nivå 2; 2017-04-07 (andbra)

Available from: 2017-04-07 Created: 2017-04-07 Last updated: 2018-09-13Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-1819-8911

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