• Title/Summary/Keyword: 조명 보상

Search Result 201, Processing Time 0.023 seconds

A Design of Electronic Ballast PFC Circuitry for 400[W] High Pressure Sodium Lamp Using the IsSPICE (IsSPICE를 이용한 400(W) 고압나트륨 램프용 전자식 안정기 역률 보상회로 설계)

  • 강응석;신대철;최종문
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.18 no.4
    • /
    • pp.8-14
    • /
    • 2004
  • In this paper, We designed the electronic ballast power factor corrected(PFC) circuity for an 400[W] hight pressure soldium lamp using boost-converter. The values of PFC elements in the proposed boost-converter circuit are calculated theoretically and performed simulation using IsSPICE. We also implemented the ballast for high pressure sodium lamp and experiments. We found that the experimental characteristics of implemented PFC circuit were same with those of simulation results. The experimental results show the performance as PF 90.3[%] at output 400(W).

A novel PFC AC/DC converter for reducing conduction losses (도통손실 저감형 역률 보상 AC/DC 컨버터)

  • Kang, Feel-Soon;Choi, Cheul;Park, Sung-Jun;Kim, Cheul-U
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.14 no.2
    • /
    • pp.52-58
    • /
    • 2000
  • This paper presents a novel power factor corrected(PFC) single-stage AC/DC half-bridge converter, which features discontinuous conduction mode(DCM) and soft-switching. The reduced conduction losses are achieved by the employment of a novel powder factor correction circuitry, instead of the conventional configuration composed of a front-end rectifier followed by a boost converter. To identify the validity of the proposed converter, simulated results of 500[W] converter with 100[V] input voltage and 50[V]output voltage are presented.

  • PDF

Suitability Review for Power Correction Parameter of Induction Motor (유도전동기 역률 보상 파라미터의 적정성 검토)

  • Kim, Jong-Gyeum
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.22 no.12
    • /
    • pp.101-109
    • /
    • 2008
  • Induction motor needs reactive power to sustain the electromagnetic field required for rotating. If reactive power is provided by the load side instead of the source side, power factor will be increased. Power factor of induction motor is usually low and needs to be compensated with power capacitor. In domestic regulations, Capacitor capacity for the power factor correction of induction motor should be complied with the recommended value by the motor output. But, at the same output, characteristics of induction motor is different from each other by the rotation speed and is not suitable for application of regular capacitor value regardless of motor's characteristics. In this paper, we compared to each other with the existing value and new proposed value with rotation speed under the same output condition, confirmed that power capacitor capacity is needed to upgrade for the better power factor.

A Study on Improving Power Quality by Real-time Reactive Power/Power Factor Compensating Equipment at Substation in Marshalling Yard (전기철도 차량기지 변전소의 실시간 무효전력/역률 보상설비 적용에 따른 전력품질 개선에 관한 연구)

  • Park, Soo-Cheol;Song, Joong-Ho
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.20 no.10
    • /
    • pp.58-67
    • /
    • 2006
  • In this paper, real-time reactive power/power factor compensating equipment is suggested for improving power quality at electrical railway's substation in marshalling yard and designing optimal capacity of compensating equipment for actual apply at current marshalling yard. For this purpose, several kind of real-time reactive power/power factor compensating equipments are introduced and SVG(Static Var Generator) as optimal compensating equipment that is suitable for load characteristics of substation in marshalling yard is suggested. This paper shows proper simulations by suggested equipment using PSIM software and describe basic compensating principle and simulation results. Optimal capacity design for applying current marshalling yard is based on real measured power quality data. Power quality improvement that is performed by SVG as real-time reactive power/power factor compensating equipment is estimated at electrical railway's substation in marshalling yard. As reference, real-time reactive power/power factor compensating equipment is composed by voltage source inverter and DC capacitors.

Illumination Mismatch Compensation Algorithm based on Layered Histogram Matching by Using Depth Information (깊이 정보에 따른 레이어별 히스토그램 매칭을 이용한 조명 불일치 보상 기법)

  • Lee, Dong-Seok;Yoo, Ji-Sang
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.35 no.8C
    • /
    • pp.651-660
    • /
    • 2010
  • In this paper, we implement an efficient histogram-based prefiltering to compensate the illumination mismatches in regions between neighboring views. In multi-view video, such illumination disharmony can primarily occur on account of different camera location and orientation and an imperfect camera calibration. This discrepancy can cause the performance decrease of multi-view video coding(MVC) algorithm. A histogram matching algorithm can be exploited to make up for these differences in a prefiltering step. Once all camera frames of a multi-view sequence are adjusted to a predefined reference through the histogram matching, the coding efficiency of MVC is improved. However general frames of multi-view video sequence are composed of several regions with different color composition and their histogram distribution which are mutually independent of each other. In addition, the location and depth of these objects from sequeuces captured from different cameras can be different with different frames. Thus we propose a new algorithm which classify a image into several subpartitions by its depth information first and then histogram matching is performed for each region individually. Experimental results show that the compression ratio for the proposed algorithm is improved comparing with the conventional image-based algorithms.

A study on Performance Improvement of SPMSM with Improved Decoupling Current Controller (개선된 비간섭 전류제어기를 이용한 영구자석 동기 전동기의 성능 향상에 관한 연구)

  • Cho, Su-Eog;Kim, Jeong-Su;Kim, Cheul-U
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.21 no.8
    • /
    • pp.151-159
    • /
    • 2007
  • This paper proposes a improved decoupling current control algorithms using a compensator to enhance the robustness to the stator inductance error. And the compensator composed from a d-axis current error for sensing change of the real stator inductance can match the estated stator inductance to the real stator inductance. A great advantage of this algorithms is more robust than feedforward decoupling current control or dynamic decoupling control. So it looks suitable to the practical applications where the exact parameters are unknown. Though simulation and experimental results with 1[kW] prototype PMSM and TMS320F2812 board for motor control, we show that the proposed controller achieves the desired performance.

Temperature compensated operation for small trichromatic LED backlight (소형 3파장 LED 백라이트의 온도 보상 구동)

  • Lee, Dong-Woo;Park, Mu-Youn;Hwang, Soo-Ryong;Kim, Jin-Ha
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.43 no.6 s.312
    • /
    • pp.33-39
    • /
    • 2006
  • Trichromatic LED backlight renders higher colour gamut and panel transmittance to the LCDs than the phosphor-converted white LED backlight. In realization, however, several technical challenges arise, such as colour shift, due to the ambient temperature change, brightness decrease along with the temperature increase, colour mixing, minimizing the total number of chips and so on. In this paper we designed and tested the low cost temperature compensating circuit, using a thermistor as a temperature compensating element, for stabilizing the brightness and maintaining the colour coordinates of the trichromatic backlight units. By applying the temperature compensating circuit, the decrement rate of the brightness and colour shift rate were achieved by 54% and 51% respectively comparing with uncompensated case.

Active Power Filter Type Uninterruptible Power Supply (UPS) (전력용 능동필터형 무정전 전원장치)

  • 김제홍;최재호
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.12 no.4
    • /
    • pp.100-105
    • /
    • 1998
  • This paper proposes a new control strategy of bidirectional uninterruptible power supply (UPS) with the performance of active power filter which compensates the harmonics and reactive power. With only one power stage, it is working simultaneously as the AC/DC rectifier/battery charger and DC/AC inverter to the operation of battery charging or back-up power supplying. Therefore the operation of the proposed system can be divided into the modes, such as the active power filter mode and the battery back-up power mode. And a novel closed-loop control strategy is used to calculate the reference current. The performance of the proposed 5[kVA] system is verified by the simulation and experimental results.

  • PDF

DC prediction based local illumination compensation (조명 불일치를 보상하기 위한 DC 기반 조명 보상 방법)

  • Park, Juntaek;Lee, Jongseok;Choi, Hansol;Park, Seanae;Oh, Seoungjun;Sim, Donggyu;Bang, Gun;Kim, Huiyong
    • Proceedings of the Korean Society of Broadcast Engineers Conference
    • /
    • 2018.11a
    • /
    • pp.165-166
    • /
    • 2018
  • 본 논문에서는 LIC(Local Illumination Compensation) 방법의 pipeline 문제를 완화하고 계산 복잡도를 줄이는 방법을 제안한다. LIC 는 현재 코딩하는 블록과 해당 블록의 참조블록의 주변에 존재하는 복원 샘플을 이용하여 선형 모델을 구한다. 따라서, 주변 샘플의 복원이 완료되기 전까지 LIC 를 수행할 수 없다는 pipeline 문제가 발생한다. 본 논문에서는 복원이 완료된 주변 샘플을 사용하지 않고, 차분 신호를 사용하여 LIC를 수행하는 방법을 제안한다. 본 논문에서 제안하는 방법의 성능을 평가하기 위하여 VTM 2.0.1 과 BD-rate 비교를 한다. 실험 결과로써 VTM 2.0.1 대비 Y 성분에 대해 평균 0.13%, U 성분에 대해 평균 -0.08%, V 성분에 대해 평균 -0.09%의 BD-rate 이득을 보인다.

  • PDF

Design of Adaptive Neuro- Fuzzy Precompensator for Enhancement of Power System Stability (전력계통의 안정도 향상을 위한 적응 뉴로-퍼지 전 보상기 설계)

  • 정형환;정문규;이정필;이준탁
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.15 no.4
    • /
    • pp.14-22
    • /
    • 2001
  • In this paper, we design the Adaptive Neuro-Fuzzy Precompensator(ANFP) for the suppression of low-frequency oscillation and the improvement of system stability. Here, ANFP is designed to compensate the conventional Power System Stabilizer(PSS). This design technique has the structural merit that is easily implemented by adding ANFP to an existing PSS. Firstly, the Fuzzy Precompensator with Loaming ability is constructed and is directly learned from the input and output data of the generating unit. Because the ANFP has the property of learning, fuzzy rules and membership functions of the compensator can be automatically tuned by teaming algorithm Loaming is based on the minimization of the ems evaluated by comparing the output of the ANFP and a desired controller. Case studies show the 7posed schema can be provided the good damping of the power system over the wide range of operating conditions and improved dynamic performance of the system.

  • PDF