• The Transactions of the Korean Institute of Power Electronics
• /
• v.14 no.6
• /
• pp.504-513
• /
• 2009

This paper proposes the new type LED driver modularization for illumination LED driver. The proposed LED driver circuit insulates a hot GND of AC input power and a cold GND of LED driver part by using a fly-back converter. In order to control easily the current of the LED, the fly-back converter is operated in the discontinuous mode with excellent dynamic characteristics, and the characteristics of the LED are verified after the closed loop control is performed using a KIA2431. The LED driver module allows the wide AC power input ranges and realizes the burst dimming function which directly regulates a PWM control IC. This paper describes the operation principle of the LED driver module and it is proved the usefulness through the real model with experimentation. Besides, this paper proposes the multi-channel LED driver which the miniaturized and modularized LED driver module are connected by parallel, and verified its propriety by experiments.

• Asia Pacific Journal of Business Review
• /
• v.2 no.2
• /
• pp.1-15
• /
• 2018

The purpose of this paper is to find out the factors responsible for purchase of LED (light-emitting-diodes) bulbs & tubes among Indian consumers and how much they are ready to replace their existing lighting system with LED fittings. A multiple regression model has been employed to investigate the factors affecting the buying decision of LED lamps in place of CFL and incandescent lamps. Eleven motives for adopting LED lamps has been identified viz. price, quality, energy saving, durability, brand, promotion, CSR, & environmental consciousness. In addition the effect of demographic variables like gender, age, household income on the purchasing decision of LED has also been examined. A total 150 respondents were contacted visiting different outlet of electrical shops of Northern Delhi. The study may helpful for the companies to decide their marketing strategies to promote LED Lamps among the consumers with an aim to save energy and save environment.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.26 no.4
• /
• pp.14-21
• /
• 2012

This paper study a method of modeling and simulation of LED driver circuit for a design optimization. Simplified LED modeling is introduced and a driver IC, HV9910, is modeled by implementing the major function blocks. Circuit of buck type converter is constructed for simulation. Simulation includes not only the internal function of IC but also the various performance results such as LED array current control and dimming. Experiment results are also shown to prove the verification of its usage. This results show that the simulation approach is valid for a circuit optimization and a reduction of development time.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.39C no.3
• /
• pp.234-238
• /
• 2014

Multichip packaging was achieved the best solution to significantly reduce thermal resistance at the same time, to increase luminance intensity in LEDs packaging application. For the packaging, thermal spreading resistance is an important parameter to get influence the total thermal performance of LEDs. In this study, silicon-based multichip light emitting diodes (LEDs) packaged module has been examined for thermal characteristics in several parameters. Compared to the general conventional single LED packaged chip module, multichip LED packaged module has many advantages of low cost, low density, small size, and low thermal resistance. This analyzed module is comprised of multichip LED array, which consists of 32 LED packaged chips with supplement power of 0.2 W at every single chip. To realize the extent of thermal distribution, the computer-aided design model of 6.4 W Si-based multichip LED module was designed and was performed by the simulation basis of actual fabrication flow. The impact of thermal distribution is analyzed in alternative ways both optimizing numbers of fins and the thickness of that heatsink. In addition, a thermal resistance model was designed and derived from analytical theory. The optimum simulation results satisfies the expectations of the design goal and the measurement of IR camera results. tart after striking space key 2 times.

• Journal of Satellite, Information and Communications
• /
• v.7 no.3
• /
• pp.116-120
• /
• 2012

There has been increased interest for building energy-saving for worldwide. There is continuing research on IT technology for efficient management of BEMS. Recently, It be able to control of LED and to maximize energy savings to the development of LED lighting technology. We propose the security image processing system to improve efficiency and we implement the real-time status monitoring system to surveil the object in the building energy management system. In this paper, we proposed the system of LED control using IP camera and Adaptive Gaussian Mixture Model for BEMS. We implement LED light control software on the based of the security camera image processing so the reliable controling based on the security camera is possible efficiently.

• KIEAE Journal
• /
• v.8 no.6
• /
• pp.21-26
• /
• 2008

According to the tendency of energy efficiency and environment-friendly chracteristics, demend of High-efficiency lighting using LED(Light Emitting Diode)are being increased actively and applied in various fields. However, In order to adequate application of LED light sources, it is necessary to lighting environment and luminous characteristics of LED light sources. This Study aims to characterize the work-plane lighting environment by LED light sources comparing with fluorescent light sources which are widely used. For the sake of this study, a fluorescent light source and 5 LED light sources were introduced and luminance and correlated color temperature were measured to evaluate luminance contrast. The experimental model is Mock-up which is $4.9m{\times}7.2m$ with a height of 2.9m. The test room was set up partition and desks. Luminance and correlated color temperature were measured work-plane on the desk which was set up local lighting by the Radiant Imaging ProMetric 1400. The optical characteristics data of LED can give a lot of advantages to design LED lighting appliances. Hereafter, the object of research will be conducted to evaluate effects of LED light sources on working performance, survey of visual performance, preference and physiology of subjects.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2010.06a
• /
• pp.162-162
• /
• 2010

In this study, optical analysis for 100W LED safety street lighting was conducted. Experimental research on such single LED was the first undertaken. simulation modeling based on optical properties of single LED has compared single LED product also designed 100W simulation modeling has compared average road illuminance with Korean Industrial Standards for LED safety street lighting(KS C7658:2009). 100W safety street lighting (model: CE180-ST-OS) designed by simulation has been also compared between product and 100W simulation modeling, and error rates have showed average 5.6[%]. Designed 100W LED safety street lighting base on simulation modeling was proven by comparison experiments. Through the simulations and the corresponding analysis, it was found that the tested 100W LED safety street lamp had reasonable performance. Design method for LED safety Street lamps have been summarized, based on the optical analysis.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2010.06a
• /
• pp.161-161
• /
• 2010

In order to achieve low power consumption and the uniform power spectrum of LED BLU (Back Light Unit) system, new circuits with a 2 stage L-C (Inductor-Capacitor) coupler have been proposed. From the simulation results based on our proposed model, the ripple power of the L-C regulation-embedded BLU circuit shows a dramatic reduction by more than 89.3% as compared to the normal BLU (without L-C circuits). This indicates that the proposed circuit is very promising for the realization of high-efficiency BLU circuits.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.24 no.9
• /
• pp.693-698
• /
• 2012

In the present work, numerical analyses of broadcasting LED light with ion wind generator have been carried out for enhancement of cooling performance. Ion wind generator is produced and experimented before analysis. With the use of result of experiments, broadcasting LED light model is computed. Ion wind velocity into LED light is varied with 0~3 m/s. Based on the numerical results, the area of duct-type ion wind generator was designed to reduce the volume flow rate of ion wind. The modified inlet geometry shows sufficient cooling capability. And, through modified ion wind generator, the volume flow rate of ion wind has been largely reduced.

• Journal of Drive and Control
• /
• v.19 no.4
• /
• pp.85-90
• /
• 2022

In this paper, a DC converter to improve the performance of Power LED system is discussed. The mathematical model of PWM converter power stage using 3-Terminal PWM cell is introduced for power LED system. A controller for DC converter system is used as a self-tunning regulator with a recursive least-squares algorithm. Minimum variance control method is used as a control law. Experiment results verified that proposed control system could improve the performance of Power LED system.