Mobile QR Code QR CODE : Journal of the Korean Institute of Illuminating and Electrical Installation Engineers

Journal of the Korean Institute of Illuminating and Electrical Installation Engineers

ISO Journal TitleJ Korean Inst. IIIum. Electr. Install. Eng.

LED서치라이트(Searchlight)의 초 협각, 고 광도 구현을 위한 광학계 설계 및 광 특성에 관한 연구 A Study on the Optical System Design and Optical Properties for the Implementation of the Super Narrow Beam Angle of the LED Searchlight

Kwang-Il Park ; Yong-Moon Yu

In this paper, an optical system with ultra-narrow angle and high brightness, which is a key element of LED searchlights that are highly used in marine and military applications, was designed, and optical properties were evaluated by manufacturing a prototype LED searchlight optical engine. In order to realize the ultra-narrow angle and high brightness of the LED searchlight, the optical system is optimally designed with a parabolic reflector and an LED light source. For the LED light source, an LED source having a high luminous flux per area (lm/m2) was selected and positioned at the focus of the parabolic reflector. Through the light tracing simulation, it was found that the larger the diameter of the parabolic reflector, the higher the luminous intensity and narrow angle can be obtained. After the optimal design of the optical system, a prototype LED searchlight optical engine was prepared and optical properties were evaluated. As a measurement result of the optical properties of the final prototype, the beam angle was 1.5 ° and the luminous intensity was 402,210cd at the power consumption of 8.3W

Elimination of Heat Problem in POF-based Daylighting Systems

Hoang Vu ; Nguyen Manh Hieu ; Tran Quoc Tien ; Ngoc Hai Vu ; Jongbin Park ; Seoyong Shin

Daylighting gets more attention as people seek better quality of light meanwhile saving electricity which in buildings. Fiberoptic based daylighting systems give us the freedom to provide natural light to any space in the building including north-facing rooms, basements, etc. Using plastic optical fibers (POFs) will significantly reduce costs for these systems. However, POFs are very sensitive to heat. The POF’s maximum operating temperature is 70°C. So, it is difficult to make a daylighting system using POFs that work stably in the long term. In this paper, a new method of eliminating the heat problem in POF-based daylighting systems was introduced. In the design, a UV-IR filter, a secondary optical element (SOE), and small silica optical fiber (SOF) bundles, were included so that the final temperature of the POFs becomes reduced to 56°C from 266°C while the ambient temperature is 35°C. This result is promising enough for POF-based daylighting systems to be installed practically. Standardization of this method for a fiberoptic daylighting system will be implemented in the near future.

에너지 절감을 위한 전기 자동차용 고효율 독립 다상 IPM BLDC 허브모터 설계에 관한 연구 High Efficiency Independent Polyphase for Electric Vehicles for Energy Saving A Study on the Design of IPM BLDC Hub Motor

Dae-Won Kong ; Dong-Il Hong ; Gi-Joo Ahn ; Hyeong-Sam Park

For an electric car traction motor has the efficiency of high efficiency motor, travel, space features efficiency as it will be motor is hub motor is suitable and to address Independent multi-phase ipm bldc the motor development test, and the tester to work with the efficiency and performance through the power to black. In addition, the most important by car accident, a secondary accident prevention must be ensured. To that end, part of the motor failure, driven by repairs in place reliable motor to an existing Y, △ structure with an independent structure have I motor. So, multi-phase independent structure with a new type I ipm bldc want to identify the characteristics of the motor, and the development of verification

수상 태양광 발전설비의 구조체용 접지전극 설치 조건에 따른 전기적 특성 분석 Analysis of Electrical Charactersitics According to Installation Conditions of Grounding Electrode for Structure use of the Floating Photovoltaic System

Yoo-Ha Kim

Currently, the exact electrical regulations for the grounding system of floating photovoltaic power generation systems have not been established. Due to the peculiarity of being installed on the water surface, the installation conditions of the ground electrode are different from that of the general photovoltaic power generation facility. Three cases can be installed where the ground electrode of the structure of the floating photovoltaic system is installed in the water, on the waterside, and on nearby land. In consideration of this case, the ground resistance was measured using a fall of potential method for a grounding method that can be applied to a photovoltaic power generation facility. Also, in the typical case, the transient potential rise value by the standard lightning current waveform was analyzed by CDEGS simulation. As a result, the grounding electrode installed in the water became the lowest grounding resistance value and exhibited the lowest transient potential rise. Since it can be installed in parallel due to the characteristics of the floating photovoltaic power generation facility, it is desirable to determine the installation location of the ground electrode in consideration of the electrical characteristics in each case.

병렬 시험 모델을 적용한 IEC 61850 클라이언트 적합성 시험자동화시스템 개발 Development of IEC 61850 Client Conformance Automation Testing System based on Parallel Test Model

Nam-Ho Lee ; Nam-Dae Kim ; Yu-Yeong Park

Modern digital substations featuring the use of the same communication protocol with the IEC 61850 standard can be guaranteed interoperability if they comply with the international standard, even if the manufacturers of devices are different, and Conformance test on international standards-based information exchange services is considered essential to verify interoperability among devices. In addition, the IEC 61850 International Standard, which is the core of the digital substation, has been reorganized into Edition 2.0 since 2012 to present new data and communication services, and the lack of securing interoperability of the substation automation system in Edition 1.0 has been supplemented, and products based on this new standard have been put on the market. KEPCO developed a test tool in 2009 that can conduct international standard conformance test for information exchange services for digital substations' operating systems and is conducting tests on domestic manufacturers. As of 2020, it applied a test tool developed during the completion of about 60 digital substations to the site and used for performance verification to ensure stable operation of the system. This paper presents a new test method called parallel test model, so it can freely verify IEC 61850 operating function, which differs from manufacturer to manufacturer, without any alteration, and it is intended to address the development of a test system that can automatically carry out IEC 61850 conformance test for operating system complying with IEC 61850 Edition 2.0.

태양광 PCS의 MPPT수와 발전량의 상관관계에 대한 실증 연구 An Empirical Comparison on the Correlation between PV PCS MPPT Number and Power Generation

Si-Ho Kim ; Cheol-Min Kim ; Nam-Jun Kim ; Jong-Soo Kim

The photovoltaic power generation system is influenced by many variables such as weather conditions, solar radiation change, terrain, module angle, module characteristics and efficiency, and inverter characteristics and efficiency. In this paper, we analyze the effect of the number of MPPTs of inverters in the photovoltaic power generation system on the amount of power generation, and selected power plants that applied inverters with different inverter types and MPPT numbers from the actual power plants in operation. Empirical evaluation is performed based on the collected data, and the difference in power generation according to monthly and weather conditions is analyzed.

제로에너지시티 계획을 위한 에너지자립률 산정 분석 및 사례 연구 Energy Independence Rate Calculation Analysis and Case Study for Zero Energy City Planning

Jung-Hyun Mun ; Jae-Chul Kim

Along with the recent rapid climate change, cities around the world are implementing the distribution and diffusion policies of zero-energy buildings to reduce carbon emissions and energy consumption. Since 2017, the Ministry of Land, Infrastructure and Transport has implemented a zero energy building certification system to save energy in buildings and achieve national greenhouse gas reduction targets.In 2019, a zero-energy pilot city that has been expanded from zero-energy buildings to city units is planned. Doing. In this study, in order to present a quantitative level for the zero-energy city, the energy self-sufficiency rate for various new and renewable energy such as the use of buildings, the expected floor number, the building area, and the usable area of ??the city space is targeted at the pilot city of the zero-energy city. We analyzed solar energy, geothermal energy, and fuel cells in addition to photovoltaic power generation facilities to improve energy independence rate at the city level.Introduced urban energy saving and management factors by presenting a minimum guideline for quantitative energy independence in new cities. can do.