• The Transactions of the Korean Institute of Power Electronics
• /
• v.10 no.4
• /
• pp.313-322
• /
• 2005

In this paper, High power factor electronic ballast using a double resonant Inverter for 250[W] MHD lamp is designed and implemented. Proposed electronic ballast is composed of configuration that is cascaded boost active PFC circuit as power factor corrector and half-bridge double resonant inverter Into two stage approach. Theoretical analysis of circuit and characteristics estimation is generally illustrated by using normalized parameter. To remove the phenomenon of acoustic resonance in the lamp, Simple frequency controller composed timer IC and driving IC is designed and employed on the ballast. The experimental results show that an high power factor electronic ballast using a double resonant inverter is operated stably.

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

• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.50 no.10
• /
• pp.530-535
• /
• 2001

Resonant-type electronic ballast for a metal halide discharge(MHD) lamp is proposed and implemented for 400W MHD lamp. HID lamps have good color rendition, long life and good focusing capability but they have flickers by acoustic resonance when driven at high frequency. A new control method is employed to remove acoustic resonance related instability in HID lamp. By using the amplitude modulation, a spread spectrum effect is employed on the ballast. The control loop of resonant inverter is analyzed and a current is designed. The ballast consists of a power factor controller, an half-bridge resonant inverter, a simple ignitor and an integrator with OP-amps. The experimental results show the good performance as PF 0.93, ballast loss 22W at output 400W and the conducted EMI level is below 60dBuV.

• Journal of Bio-Environment Control
• /
• v.22 no.4
• /
• pp.400-407
• /
• 2013

This study was performed to analyze the effect of light quality of discharge lamp on growth and phytochemicals contents of lettuce (Lactuca sativa L. cv. Jeokchima) grown under metal halide (MH) lamp, high-pressure sodium (HPS) lamp, and xenon (XE) lamp in a plant factory. Cool-white fluorescent (FL) lamp was used as the control. Photoperiod, air temperature, relative humidity, $CO_2$ concentration, and photosynthetic photon flux (PPF) in a plant factory were 16/8 h (day/night), $22/18^{\circ}C$, 70%, 400 ${\mu}mol{\cdot}mol^{-1}$, and 200 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, respectively. MH lamp had the greatest fraction of blue light (400-500 nm) of 23.0%. However, HPS lamp had the lowest fraction of 4.7% for blue light and the greatest fraction of 38.0% for red light (600-700 nm). At 11 and 21 days after transplanting, leaf length, leaf width, leaf area, shoot fresh weight, and shoot dry weight of lettuce as affected by the light quality of the discharge lamp were significantly different. The leaf area of lettuce grown under HPS, MH, and XE lamp increased by 45.7%, 16.3%, and 9.5%, respectively, as compared to the control. These results were similar for shoot fresh weight. Growth characteristics of lettuce grown under HPS lamp increased since HPS lamp had more fraction of red light. However, growth of lettuce grown under MH and XE lamp decreased since they had more fraction of blue light. As compared to the control, the ascorbic acid in lettuce leaves grown under discharge lamp decreased. The greatest anthocyanins accumulation of 0.70 mg/100 g was found at MH treatment. Anthocyanins content in lettuce leaves grown under XL and HPS lamp were 79.3% and 8.6%, respectively, compared with the control. Growth and phytochemicals contents of lettuce were highly affected by the different spectral distribution of the discharge lamp. These results indicate that the combination of discharge lamp or LED lamp for enhancing the light quality of discharge lamps is required to increase the growth and phytochemicals accumulation of lettuce in controlled environment such as plant factory.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.56 no.3
• /
• pp.531-537
• /
• 2007

This paper presents a new method for determining L, Cs, and Cp in a series parallel resonant inverter. This inverter is suitable for driving high-intensity discharge (HID) lamps. The operating frequency is selected to avoid acoustic resonances which are governed by the size and shape of the arc tube. L, Cs and Cp, are chosen to satisfy the ignition and steady state requirements of the lamp. Equations are developed to analyze the starting condition and steady state operating condition of the lamp. For the prototype ballast for a 250W Metal Halide Lamp, experimental results are presented in order to validate the proposed method.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2000.11a
• /
• pp.111-115
• /
• 2000

In this paper, a prototype electronic ballast for 400W MH lamps is designed and implemented. To remove the phenomenon of acoustic resonance in the lamp being operated at high frequency, a spread spectrum method is employed on the ballast. Half-bridge resonant inverter, voltage-controlled-oscillator and PFC are used and the current of lamp is controlled with taking into account the voltage of lamp. The ballast is built with analog OP-amps and MOSFETs. The experimental results show the good performance as PF 0.93, ATHD 0.14, Ballast loss 22W at output 400W.

• Proceedings of the KIEE Conference
• /
• 1999.07f
• /
• pp.2562-2564
• /
• 1999

We have development the electronic ballast for metal halide discharge (MHD) lamp. The ballast consists of the boost pre-converter for power factor correction (PFC), a flyback a converter, half-bridge inverter and ignitor. To reject acoustic resonance phenomena, we have designed electronic ballast driving with the low frequency square wave. As results of this study, the ballast had not flicker phenomena and promoted corrected the factor (PF) highly

• Journal of the Institute of Electronics and Information Engineers
• /
• v.54 no.4
• /
• pp.108-112
• /
• 2017

High-intensity-discharge lamps are widely utilized in outdoor and indoor lighting circumstances that need high luminance. In lighting applications for MHD lamps, the size of the lamp ballast circuit is an important factor and should be as small as possible. The electronic ballast for MHD lamps is superior to the electromagnetic(EM) ballast in that it saves energy, and has smaller volume and lighter weight. In this paper, highly efficient cost-effective and small sized electronic ballast for Metal Halide Lamp with high power factor using Digital Signal Processor are proposed. The proposed electronic ballast for MHD lamps combines a boost PFC converter with a half-bridge inverter, the algorithms of the power factor correction and ballast control were implemented using the TI's TMS320LF2406 CPU. Experimental results validate the ballast is also useful and reasonably suggested.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.4 no.5
• /
• pp.405-412
• /
• 1999

Meta! Halide Discharge(]\1HD) Iamps have good color rendition, long life and good focusing capability but h have flickers bv acoustic resonances. We have designed the electronic ballast for reducing acoustic resonances in high pressure discharge tube. The ballast consists of main two parts, the first part is a half-bridge inverter to make a square wave form a and the st'Cond part is a flyback converter to combine the low frequency and high frequency component. As a r result of this study, we conclude that MHD lamps of 70 watt 따c very well light(D without acoustic resonance p phenomena by the elestronic ballast.

• Proceedings of the KIPE Conference
• /
• 2001.10a
• /
• pp.737-740
• /
• 2001

This paper proposes a new ballast that is ignited by internal LC resonance of buck converter. In order to cancel the steady state current ripple, the proposed ballast utilizes the coupled inductor filter which minimizes the size and weight of the ballast. The operation mode of the proposed ballast is analyzed and the performance of the new ballast is verified by the experimental results from a HOW prototype ballast for metal halide discharge (MHD) lamp.