• Journal of Industrial Technology
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• v.30 no.B
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• pp.109-112
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• 2010

Unlike the general lighting systems, stage lighting system requires accurate dimming control and reduction of flicker phenomenon. In this paper, we studied PWM dimming control and linear voltage level control methods. PWM Dimming is easy control and flicker phenomenon of linear voltage level dimming does not happen by experiment result. We concluded that stage lighting dimming system required to combine two techniques of the PWM and linear voltage level dimming control method.

• Journal of the Korea Society of Computer and Information
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• v.21 no.5
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• pp.127-133
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• 2016

In this paper, an intelligent dimming control system is designed and implemented with the human visual response function using CDS sensor, PIR sensor and temperature sensor, etc. The proposed system is designed to detect a moving object by PIR sensor and to control the LED dimming considering the human visual response. Also, the dimming of LED light can modulate on the app, and simultaneously control dimming in real-world environments with smart phone app. A high-temperature warning or a fire hazard information is transmitted to user's smart phone according to sensor values and Data graph are provided as part of data visualization. Connecting the hardware controller, the proposed intelligent smart dimming control system is expected to contribute to the power reduction interior LED, smart grid building and saving home combining with internet of things.

• Journal of Convergence for Information Technology
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• v.8 no.5
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• pp.153-158
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• 2018

In this paper, we have studied a dimming level control method to satisfy both lighting and communication performance in visible light communication system. In the case of the most commonly used OOK and RZ-OOK modulation schemes, continuous Burst Zero Duration will seriously degrade the lighting function. This causes not only the illumination but also the performance of the entire system to deteriorate. Through this study, we analyzed the dimming level characteristics of the existing system and proposed the Illegal Pulse Insertion (IPI) algorithm as a technique to increase the dimming level. Through this, it is possible to effectively control the dimming level and improve the QoS of both lighting and communication by resolving the flicker phenomenon and dimming level reduction in the existing modulation and demodulation system.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.54 no.1
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• pp.47-52
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• 2005

This paper presents dimming control system for automotive 35W metal halide discharge(MHD) lamp electronic ballast. HID lamp demands a highly efficient ballast and very complex control circuitry that can control complex transient state in applying to automotive. Therefore, in this paper, a microcontroller-based digital control method for the HID lamp ballast is presented for optimal control that can adapt complex transient state, steady state and various environments. In developed dimming system, the system is designed to control the lamp output voltage step by step(continuous) using microcontroller according to CdS sensor. Therefore the designed dimming control system give good driving condition to diver and realize the power control effectively. The results of the proposed system is verified through various experiment results.

• Journal of the Korean Solar Energy Society
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• v.28 no.5
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• pp.36-48
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• 2008

This study examines the influence of control algorithms on dimming performance to determine appropriate control setting when direct/indirect lighting is controlled by a daylight dimming system. Computer simulation were performed for a small office with double skin envelope under various daylight conditions. A retractable fabric shading and Venetian blind were applied for internal and external envelopes under three CIE standard sky conditions. Unshielded and partially-shielded photosensors were used, and three control algorithms were applied for the sensors. In general, dimming level was too excessive due to the direct impact of light from lighting fixture to the photosensor. Providing insufficient lighting output, the unshielded photosensor completely failed to secure required illuminance under any daylight condition. When a partially-shielded photosensor was applied under clear sky, three setting points functioned effectively. Less sensitivity for the partially-shielded photosensor was effective to control the dimming system optimally with reasonable energy saving. However, the daylight dimming control system for direct/indirect lighting does not appear to be energy effective when photosensors without enough shielded area is installed on ceiling where light from fixtures reaches directly.

• Proceedings of the KIPE Conference
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• 2004.07b
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• pp.834-838
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• 2004

This paper presents the structure of a dimming control system for multiple fluorescent lamps. The dimming control system is composed of a phase angle controller, a transducer, and dimmable ballasts. In these ballasts, dimming control is achieved by varying the switching frequency that is controlled by the external DC level.

• KIEAE Journal
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• v.10 no.6
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• pp.33-39
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• 2010

Visual Environment and productivity are correlated. So we need to create a comfortable visual environment and maintain proper workplane illumination level. We can obtain lighting energy savings and comfortable visual environment using daylight and LED lights. In this study, we characterized the indoor illuminance level according to the sky condition and proposed dimming control strategy of LED lights. Energy savings in On/Off control mode are 40% at clear sky and 28% at intermediate sky. In dimming control mode, energy savings are 77.2% at clear sky and 64.1% at intermediate sky. Then we obtain the appropriate dimming control strategy of LED lights based on data. Dimming rates are 0-14.2-80(min-avg-max, %) for LED 1, 0-19.9-60% for LED 2 and 30-61.4-90% for LED 3. Lighting energy savings are 68.2% for LED dimming system applied this control method.

• Journal of Industrial Technology
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• v.30 no.B
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• pp.113-118
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• 2010

In this paper, We proposed remote dimming control system for Light Emitting Diode(LED) street light using Power Line Communication(PLC). LED will be used widly by indoor or outdoor lighting because of semi-permanent life and environment restriction. For energy saving of street light, the dimming control system is very necessary and the PLC is a very efficient technique. Thus, in this paper we proposed the remote dimming control system for LED street light using PLC. A performance of the proposed system was validated by experimental results.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.5
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• pp.15-21
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• 2003

This paper presents field measurements on daylighting and electric lighting with dimming controlled systems for a small office in Seoul, Korea. And the main purpose of this study is to provide the evaluation data of lighting energy performance when a dimming system is installed. For the performance evaluation, the mock-up room(3.6x7.2x2.6[m]) was used for the actual test. The results of this study were as follows; 1) The correlation between daylight illuminance at a workplane(Ed) and the photosensor signal(Sd) was an important factor affecting the performance of daylight responsive dimming system, 2) The mock-up office space gained a sufficient workplace illuminance of 579[lux] with the dimming control system 3) About 53[%J of monthly lighting energy could be saved using the dimming control system.

• Journal of Sensor Science and Technology
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• v.28 no.3
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• pp.191-197
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• 2019

In this study, we propose a dimming control method for a visible light communication (VLC) system, in which the subcarrier on-off keying (OOK) modulation of Manchester code is used for data transmission. In the VLC transmitter, non-return-to-zero (NRZ) code data is transformed to Manchester code, which is OOK modulated with a subcarrier. Manchester code is used for flicker-free lighting; the duty factor is changed for dimming control, and the subcarrier is used for preventing the adjacent noise light interference. In the experiments, the dimming control was carried out from about 8%-92% of the continuous wave (CW) LED light. This configuration is simple and effective in constructing a VLC system for indoor wireless sensor networks with flicker-free illumination and dimming control capability without adjacent noise light interference.