• Journal of Industrial Technology
• /
• v.23 no.A
• /
• pp.35-39
• /
• 2003

There are many kinds of electronic ballast for various kinks of fluorescent lamps. The PFC(Power Factor Correction) circuit in electronic ballast is classified in two types. One is the active PFC and the other is the passive PFC circuit. The active type PFC is higher than the passive type, but the cost of the passive type is cheaper than the active type. In this study, we introduced the modified passive PFC method which is called semi-boost PFC, and then we analyzed and experimented the electronic ballast which is composed of the semi-boost PFC, half-bridge, and LCC resonant tank. Experimental results showed that the $$PF{\geq_-}0.98$$, $$CF{\leq_-}1.4$$ and input current $THD{\approx}15%$.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.15 no.5
• /
• pp.394-400
• /
• 2010

In this paper, We proposed electronic ballast that applys Buck Converter operation principle to Full-Bridge inverter. The proposed ballast consists of an EMI Filter, a full-bridge rectifier, a passive power factor correction (PFC) circuit and a full-bridge inverter. The passive PFC is used and a Full-Bridge inverter operation by two frequency. High Side and Low Side switch was driven by high frequency and low frequency and realized buck Converter's operation. The lamp is driven by Low Frequency square wave to avoid Acoustic Resonance. Also, bulk of inductor is reduced by high frequency switching. Performance of the proposed ballast was validated through computer simulation using Pspice, experimentation and by applying it to an electronic ballast for a prototype 700W MHL.

• Proceedings of the KIPE Conference
• /
• 1999.07a
• /
• pp.266-269
• /
• 1999

Several power factor correction(PFC) circuits are presented to achieve high PF electronic ballast for both voltage-fed and current-fed electronic ballast. The proposed PFC circuits use valley-fill(VF) type DC-link stages modified from the conventional VF circuit to adopt the charge pumping method for PFC operations during the valley intervals. In voltage-fed ballast, charge pump capacitors are connected with the resonant capacitors. In current-fed type, the charge pump capacitors are connected with the additional secondary-side of the power transformer. The measured PF and THD are higher than 0.99 and 15% for all proposed PFC circuits. The lamp current CF is also acceptable in the proposed circuits. The proposed circuit is suitable for implementing cost-effective electronic ballast.

• Proceedings of the KIEE Conference
• /
• 1995.11a
• /
• pp.235-237
• /
• 1995

The demands of minimizing the reactive power and reducing. the current harmonics are increasing nowadays. The inverter airconditioner needs high power and it operates with wide load range. Conventionally, ah huge LC passive filter is used in airconditioner to improve the P.F and to reduce current harmonics which doesn't gives good results. In this paper, a design of active power factor correction(PFC) circuit for inverter air conditioner is described. To improve the P.F and to reduce the THD, an average current controlled active PFC is designed and tested. Experimental results show that the developed system achieves almost unity P.F and low THD for all load range.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.3 no.4
• /
• pp.298-306
• /
• 1998

MOSFET 스위치로 구현된 고역률 부스트 정류기에 적합한 무손실 수동스너버가 턴오프 및 턴온 동안에 동작하는 등가회로로 기술된다. 이러한 등가회로는 주스위치에 가해지는 과도전압, 스너버 전류, 및 턴-오프 과도시간을 예측할 수 있도록 분석된다. 제안된 스너버와 결합된 부스트 컨버터의 주 스위치는 영전류에서 턴-온되기 때문에 턴-온 손실이 거의 없고, 제한된 전압 스트레스에서 턴-오프되므로 주 스위치의 전압 스트레스에 의한 파손을 방지할 수 있다. 또한 본 스너버를 사용한 부스트 컨버터의 제어 방법이 기존의 부스트 컨버터와 동일하기 때문에 기존의 부스트 컨버터용 제어회로를 그대로 쓸 수 있다. 제안된 에너지재생 수동스너버를 갖는 고역률 정류기가 구현되고 실험결과가 제시된다.

• Proceedings of the KIEE Conference
• /
• 1997.07f
• /
• pp.2255-2258
• /
• 1997

We have develped the electronic ballast for 32watt/1 fluorescent lamp. in this research. the circuit is analyzed by the P-spice program and designed to match the ballast with the fluresecnt lamp characteristics. The power factor correction circuit has been designed with all passive elements and then achived the slim-line type ballast.

• Proceedings of the KIEE Conference
• /
• 1999.07f
• /
• pp.2559-2561
• /
• 1999

The life of a fluorescent lamp is greatly affected by starting scenario and crest factor. This paper will propose a new crest factor control method in electronic ballast for fluorescent lamp using Pulse Frequency Modulation (PFM), which employs a passive Power Factor Correction (PFC) circuit in the input stage. The operation of parellel-loaded circuit, the switching frequency. and the characteristics of electronic ballast with the proposed PFM control scheme are described in detail, and its validity is verified by the simulation results.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.59 no.5
• /
• pp.904-911
• /
• 2010

This paper presents the design of acoustic resonance free and over current limit during transient state consideration electronic ballast for 1.5kW Metal-Halide Lamp(MHL) that employs frequency modulation (FM) technique. The proposed ballast consists of a Full-Bridge(FB) rectifier, a passive power factor correction (PFC) circuit, a full-bridge inverter, an ignitor using LC resonance and a control circuit for frequency modulation. The frequency modulation technique is the most effective solution to eliminate acoustic resonance among other technique. It spreads power spectrum of lamp to reduce the supplied power spectrum under the energy level of eigen-value frequency. Moreover, the proposed ballast is simple and cost effective above conventional ballast. A new PFC circuit is proposed which combines with LCD type and PCSR filter. A new PFC circuit has higher PF and lower THD than conventional LCD type and secure high reliability. Finally, to protected switching components in transient state, the surge current into ballast is limited by increase the switching frequency. Performance of the proposed ballast was validated through computer simulation using Pspice, experimentation and by applying it to an electronic ballast for a prototype 1.5kW MHL.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.57 no.4
• /
• pp.370-376
• /
• 2008

Power capacitors is widely used for power factor correction and component of passive filter in the user power systems. Recently, application of non-linear load is gradually increased. Non-linear load produces harmonic components of current. There are series resonance and parallel resonance when capacitors are applied in the user electrical application. If this harmonic component matches resonance, voltage and current is magnified and has severely an influences on capacitor. This paper purposes a new method for the magnitude of voltage and current by the frequency scan analysis without equivalent circuit for the actual circuit at the resonance condition.

• Journal of information and communication convergence engineering
• /
• v.5 no.4
• /
• pp.362-368
• /
• 2007

A single-phase uninterruptible power supply system equipped with a superconducting magnet energy storage unit is proposed to achieve a simple circuit configuration and higher system reliability. It reduces a number of switching devices by applying a common-arm scheme. Removing some switches or substituting passive elements for active switches can increase the sophistication and reduces degree of freedom in control strategy. However, high-performance DSP controller can execute the complicated control task with no additional cost. Operational principles to normal, stored-energy, and bypass mode are discussed in detail. The validity of the proposed system is verified by experimental results.