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    Assessment of photometric and electrical measurements of residential light sources
    (Springer Science and Business Media Deutschland GmbH, 2021) Doğanşahin, Kadir; Ayaz, Ramazan; Bozkurt, Altuğ; Kekezoğlu, Bedri
    The development of light sources that provides lighting with electrical energy has a history of about 200 years and it has still been continuing today. Over the time, diferent light sources have been developed by the use of diferent technologies. Eventually, a large product inventory comprised from light sources in diferent structures and characteristics has been obtained. Residential lighting is an important feld in the sector in terms of appealing large number of users and a wide range of application areas. In addition, lighting quality is prioritized in residential buildings, because people get more closely exposed to artifcial light in those places. In this study, the most commonly used eight diferent light sources in residential buildings have been investigated. The selected light sources are comprised of the products from halogen, CFL and LED lighting technologies. All the light sources have been chosen with equivalent luminous fux values. The selected light sources have been subjected to photometric and electrical measurements realized simultaneously under the same ambient conditions. The interactions between photometric parameters and the meaning of these magnitudes in terms of users have been tried to be explained in an explanatory language. For the same purpose, electrical parameters have been also examined and their meanings terms of both the user and system have been given. Based on the results obtained, evaluation of the light sources selected from diferent technologies have been provided sophisticatedly and their suitability in terms of users and systems have been discussed. In the last part, the loading efcacy value has been examined and reference has been made to the appropriateness of the use of this value in expressing the efciency of the light sources.
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    Harmonic behaviour of RGB WLED
    (IEEE, 2019) Doğanşahin, Kadir; Ayaz, Ramazan; Bozkurt, Altuğ; Kekezoğlu, Bedri
    For the last few years, there has been a decrease in electricity consumption for lighting purposes. The reason for this decrease is the widespread use of energy saving lighting elements that have high efficacy factor. LEDs are one of these lighting elements and have a very important role on energy saving lighting. On the other hand, power quality problems have started to be experienced more frequently and seriously, so it has become an important issue nowadays. Light emitting diodes are a closely related in both subjects. In this study, the harmonic behavior of RGB WLEDs, which has gained importance recently and has become increasingly widespread, has been investigated. RGB WLEDs, which are quite different from monochrome LEDs in terms of package contents and driver circuit, are expected to behave differently in terms of harmonics. In order to observe that, an appropriate test setup has been established and the power quality measurements of an RBG WLED sample have been performed for different operating cases. In the conclusion of the study, the enlightening results about the harmonic behavior of RGB WLEDs were obtained.
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    Power quality assessment of indoor LED luminaires
    (IEEE, 2019) Ayaz, Ramazan; Doğanşahin, Kadir; Bozkurt, Altuğ; Kekezoğlu, Bedri
    Due to the fact that it is a semiconductor based lighting equipment, the LEDs have important effects on the power quality. In the ever-expanding lighting industry, the use of LED equipment is increasing day by day. Therefore, it is very important to analyze and interpret the effects of LEDs on the grid. In this study, power quality measurements of 4 different commercial LED luminaires have been realized and the results obtained have been interpreted. According to the measurements, it is found that the power factor values are acceptable for the luminaries when they are completely on. However, when the luminaries are dimmed, it has been observed that the power factor decreased and the current harmonics exceeded the limit values determined by the related standards. On the other hand, it is seen that all the luminaires provide flicker boundaries. As a result of the study, it has been concluded that the effects of dimmable equipment on power quality should be analyzed in more detail.