• The Journal of the Korea institute of electronic communication sciences
• /
• v.16 no.2
• /
• pp.255-260
• /
• 2021

The importance of electric vehicles is gradually increasing due to the recent depletion of fossil fuels. In order to use an electric vehicle, the battery built into the vehicle must be frequently charged. Electric vehicles has very good performance in terms of noise and vibration. However, due to the limitations of the battery, the mileage is considerably shorter than that of an internal combustion engine vehicle once it is charged, and the battery charging time is relatively long compared to the refueling time. There are two types of charging methods for electric vehicle batteries: plug-in and wireless charging. In this paper, we introduced the wireless charging technology for electric vehicles and the current state of technology development and standards in major countries.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2018.06a
• /
• pp.349-350
• /
• 2018

본 논문에서는 전기 자동차 충전소의 전력 소모량 추정 알고리즘을 웹 서버에 도입하여, 충전소에 의한 전력소비가 주변 전력 계통에 미치는 영향을 모니터링할 수 있는 시스템을 제안한다. 우선, 관련 기관으로부터 공급 받는 지역 내 실시간 충전소 별 이용 상태 정보로부터 충전 시간과 그 횟수를 도출하고, 이를 충전소 마다 누적하여 소비 전력을 추정한다. 이렇게 추정된 충전소 별 전력 소모량을 웹 페이지를 통해 사용자에게 시각화하여 제공한다. 또한 같은 지역의 구간별 실시간 교통량 또한 같은 방식으로 제공하여, 전기 자동차 충전소 전력소모량의 변화 추이와 교통량의 변화 추이 간 상관관계를 확인할 수 있도록 한다. 따라서 제안하는 시스템은 지역 내 전기 자동차 충전소의 전력 소모량 및 그 변화 추이 관측하고 이를 바탕으로 지역 내 충전소 추가 설치 필요성, 전력 계통 부하 예측, 충전소 재배치 등 전기 자동차 충전소 운영 전략을 수립하는데 사용할 수 있다.

• Proceedings of the KIPE Conference
• /
• 2008.06a
• /
• pp.618-620
• /
• 2008

본 논문에서는 대기 오염 물질의 방출이 적고, 소음이 적은 환경 친화적인 Ni-MH전지를 독립형 태양광 가로등시스템에 적용하였으며 충방전제어기를 구성하여 출력특성을 고찰하였다. 출력특성을 고찰한 결과 충전 및 방전이 원활히 진행됨을 알 수 있었다. 그러나 충전시 정전압 충전방식을 사용하였고 태양 전지 출력측에 MPPT제어가 이루어 지지 않은 탓으로 태양전지 이용률이 떨어지며 화창한 날 태양전지의 등가 발전시간은 약 6시간에서 7시간 정도 나오지만 축전지는 오전 중에 충전이 완료되고 오후발전량은 모두 버리게 됨을 알 수 있었다.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.21 no.5
• /
• pp.885-892
• /
• 2017

In this paper, we proposed a novel crowbar circuit for high-speed discharge charge switching to solve discharge charge-time delay of supply voltage in the conventional crowbar circuit. The proposed circuit is designed to increase the charge-speed after high-speed discharge of supply voltage, thereby reducing the time exposed to radiation damage and, the normal operation time of electronic system after passing the pulse radiation. The simulation of the discharge charge-times before the implement of the hardware is conducted using Cadence's pspice tool, and DUT (Device Under Test) board is fabricated in the device level. The comparison measurement of the crowbar circuits is performed on the satellite-electronic device for 24V. As the result, we confirmed the high-speed function of the proposed circuit by improvement of the discharge-speed 96.8% and the charge-speed 27.3% as compared with the conventional circuit.

• Journal of IKEEE
• /
• v.22 no.2
• /
• pp.369-374
• /
• 2018

In this paper, the energy cost saving in multi-channel electric vehicle charging system. Joint use of the electric car charger battery state of charging proposed a method based charging. A linear programming with two type is used for optimal control, and the time-of-use price is included to calculate the energy costs. Simulation results show that the reductions of energy cost and peak power can be obtained using proposed method.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.87-88
• /
• 2011

전기 자동차는 내연기관 차량을 대체할 차세대 그린카의 대표 차종으로 부각되고 있다. 전기 자동차가 상용화되기 위해서는 전기자동차 자체의 성능뿐만 아니라 충전 인프라 발전이 함께 이뤄져야 한다. 현재 개발된 전기 자동차의 경우 충전 시간이 긴 반면 주행 거리가 짧기 때문에 효용성이 크게 떨어진다. 따라서 충전 시간을 최대한 단축 시키기 위한 급속 충전 시스템 개발이 활발하게 진행되고 있다. 본 논문에서는 전기 자동차용 급속 충전기에 적용되는 실제적인 DC-DC 컨버터를 ATPDraw/MODELS를 이용해 모델링하고 검증하였다.

• Journal of Advanced Navigation Technology
• /
• v.20 no.1
• /
• pp.86-92
• /
• 2016

Recently, solar module is installed in crowded areas to offers services so that people can charge their smartphones or tablets. However, the burden in terms of cost is high to install in areas where utilization ratio is low and installation is difficult in limited spaces. In this paper, a system for collecting and providing the optical power is proposed from the analysis about the person that receives service in each area using the real-time data provided by the state and collected from the actual environment as well as considering the waiting time and the solar charging time in different environments. As a result, This study shows that charge was not delayed since collecting power exceeds charging power. Smartphone was fully charged in ninety-five minutes. we confirmed that with one smartphone, it can be charged a approximately fifty percent of the battery in between ten to twenty minutes, with multiple units they can be charged a approximately twenty percent of the battery in between ten to twenty minutes.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.12 no.1
• /
• pp.121-135
• /
• 2013

This paper propose an efficient algorithm for selecting electric bus charging facility location. In nature, the optimal charging facility location problem is similar to Set Covering Problem. Set Covering Problem is the problem of covering all the rows of an $m{\times}n$ matrix of ones and zeros by a subset of columns with a minimal cost. It has many practical applications of modeling of real world problems. The Set Covering Problem has been proven to be NP-Complete. In order to overcome the computational complexity involved in seeking optimal solutions, this paper present an enhanced greedy algorithm and simulated annealing algorithm. In this paper, we apply the developed algorithm to Seoul's public bus system.

• Vending industry
• /
• v.2 no.4 s.5
• /
• pp.76-77
• /
• 2002

지난 한해 핸드폰 충전자판기는 가히 폭발적이라 할 만큼 시장 특수를 기록한 한해 이었다. 이동전화 가입자수가 3,000만에 육박하는 시대에 있어 적재적소에 핸드폰 충전을 할 수 있게 한 이 자판기의 성공은 시대의 흐름과 유행에 적절히 부합하는 기획상품의 중요성이 얼마나 큰지를 여실히 보여줬다. 이제는 즉석 핸드폰 충전이 낯설지 않은 문화로 자리 잡은 현실에서 최근 이와는 차별화한 휴대폰 관련 자판기가 등장해 큰 관심을 끌고 있다. 충전에 일정시간이 소요되는 충전자판기에 비해 즉석에서 바로 사용할 수 있다는 장점을 가진 휴대폰 건전지 자판기가 바로 그것. 이제피아에 의해 시도되는 새로운 휴대폰 부가 서비스 자판기의 가능성을 진단해 봤다.

• Resources Recycling
• /
• v.7 no.4
• /
• pp.27-34
• /
• 1998

In this research, the processing control of NiCuZn Ferrite (NCZF) had been studied. NiCuZn Ferrite, which calcined at $700^{\circ}C$ for 3 bours, was ball milled for about 60 hours to ill김ke a size of $0.5\mu\;extrm{m}$ followed by granulation using spray dryer Apparent densincatioo rate and initial permeability of NiCuZn Ferrite with an initial packing density had been investigated as f follows. 1.The relative packing density of NCZF green body increas$\xi$d in the range of 48.6-56.8% with an increased forming pressure of 20-170 MPa. 2. The higher the relative pac퍼ng density of NCZF and the sintering temperature are, the higher the initial densification rate. The increased bulk rlcnsity of NCZF was attributed to the densification rate with decreased open pore and increased closed pore as the relative packing density, sintering temperature, and sinteriog tim$\xi$ increased. 3. The initial P permeability of NCZF with constant composition is logarithmically proportional to the bulk density of NCZF sintered at $875~925^{\circ}C$ for 0-5h, and strongly depended on the relative packing density of NCZF green body. The empirical equation is as f follows; log $\mu$i=$G1{\times}BD$+$G2{\times}RPD$+b(0);where, G1, G2; gradient, B.D: bulk density, RPD; relative packing density, b(0); intercept.