• Journal of international Conference on Electrical Machines and Systems
• /
• 제1권1호
• /
• pp.40-46
• /
• 2012

This paper presents contactless power supply systems using the Valtchev model in transportation systems. The major drawback of contactless systems is that the efficiency is lower than that of contact systems. The coupling coefficient of the contactless transformer is the most influential parameter on the system efficiency. Here, a new computer model for the contactless transfer system developed in the Korea Railroad Research Institute is presented. Also, simulations of the old model and the new model are compared with the prototype measurement to assure the model validity.

• Journal of international Conference on Electrical Machines and Systems
• /
• 제1권4호
• /
• pp.483-491
• /
• 2012

It is expected that, in the future, DC power service will be widely used for photovoltaic home power generation systems, since DC consuming devices are ever increasing. Instead of using multiple converters to convert DC to AC and then AC to DC, the power service could solely be based on DC. This would eliminate the need for converters, reducing the cost, complexity, and possibly increasing the efficiency. However, configuration of direct DC power service with mechanical contacts can cause spark voltage or an electric shock when the switch is turned on and off. To solve these problems, in this paper, a contactless power supply for a DC power service that can transfer electric power produced by photovoltaics to the home electric system using magnetic coupling instead of mechanical contacts has been proposed. The proposed system consists of a ZVS boost converter, a half-bridge LLC resonant converter, and a contactless transformer. This proposed contactless system eliminates the use of DC switches. To reduce the stress and loss of the boost converter switching devices, a lossless snubber with coupled inductor is applied. In this paper, a switching frequency control technique using the contactless voltage sensing circuit is also proposed and implemented for the output voltage control instead of using additional power regulators. Finally, a prototype consisted of 150W boost converter has been designed and built to demonstrate the feasibility of the proposed contactless photovoltaic DC power service. Experimental results show that 74~83% overall system efficiency is obtained for the 10W~80W load.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
• /
• pp.703-706
• /
• 2011

Contactless systems use electromagnetic fields to transport power from railway substation to the traction system. In Korea Railroad Research Institute, KRRI, the RIPS (Railway Inductive Power Supply), has been developed. The RIPS is based on a contactless transformer with a fixed coreless primary and a moving core, compared with E shape and U shape, in the secondary. The primary coil is supply with 20 kHz current which produces a magnetic flux in the secondary core. Further this flux induces a current in the secondary coil.

• 한국산업정보학회논문지
• /
• 제26권1호
• /
• pp.41-54
• /
• 2021

기존의 제조업 기반의 현장에서 적용되고 있는 로봇 및 이송시스템의 선형 전동기 활용에 있어서, 케이블을 통한 전력공급으로 인해 작업 환경 개선 및 기술적 고도화에 어려움을 겪고 있다. 따라서, 본 논문에서는 이러한 문제점의 해결을 위해 적용될 수 있는 비접촉 전력전송 시스템에 대해서 FEM 기반의 물리해석 프로그램을 활용하여, 2D와 3D의 자계 해석을 바탕으로 비접촉 전력전송 시스템용 고주파 코일 형상 및 전력변환 시스템에 관한 특성을 연구하였다.

• 조명전기설비학회논문지
• /
• 제22권5호
• /
• pp.31-40
• /
• 2008

최근 FPD 산업에서 물류이송장비의 전원장치로 비접촉 전원장치에 관한 연구가 활발히 진행되고 있다. 양산 라인에 적용되고 있는 물류장비의 비접촉 전원장치는 주로 직선구간을 왕복하고, 이송대차가 한 대인 경우에 적용하고 있다. 그러나 곡선 구간과 이송대차가 다수인 경우의 물류이송장비에는 적합하지 않다. 따라서 본 논문은 직 곡선 구간이 혼용되어진 구조이고, 이송대차가 한 대 이상으로 구동되는 물류이송장비의 비접촉 전원장치 시작품에 적용하였고, 적용된 비접촉 전원장치의 회로 구조는 풀 브릿지 구조를 갖는 직 병렬 공진 DC/DC 컨버터 회로로 하여 회로해석, 제어방법, 특성평가, 실험을 통한 적용 가능성에 대한 연구를 행하였다. 또한 비접촉 전원장치의 전체 제어는 1차측 전원공급장치에 일정한 공진전류를 제어하기 위해 듀티 제어를 사용하였고, 2차측 전원공급장치의 출력전압을 일정하게 유지하기 위해 다수의 이송대차가 자체 제어를 하도록 구성하였다. 실제 2대의 이송대차를 제작하여 직 곡선 구간을 구성하고, 물류이송장비를 운용하여 양호한 특성으로 적용 가능함을 알 수 있었다.

• 센서학회지
• /
• 제14권2호
• /
• pp.78-84
• /
• 2005

A contactless recharging device for totally implantable middle ear systems has been designed as a pillow type that the user can recharge the implanted battery with taking a rest. The proposed device uses the electromagnetic coupling between the transmitting coil and the receiving coil. To supply sufficient power for the implanted circuits, each coil uses LC resonance and the implanted device uses voltage doubler. A power MOSFET is used for switching the DC voltage of LC parallel circuit and the switching frequency demands on a programmable frequency generator which is controlled by microcontroller. In order to improve the electromagnetic coupling efficiency at specific positions of coil which may vary with the displacement of head, the optimal location of receiving coil was studied, and the 5 transmitting coils in a pillow for recharging the implant module was designed. From such a recharging experiment, it was found that the proposed device could provide the sufficient operating voltage within the distance of 4 cm between pillow and the implanted device.

• 제어로봇시스템학회논문지
• /
• 제17권6호
• /
• pp.566-572
• /
• 2011

In recent semiconductor and FPD (Flat Panel Display) manufacturing processes, high clean-class delivery operation is required more and more for short working time and better product quality. Traditionally SLIM (Single-sided Linear Induction Motor) is widely used in the liner drive applications because of its simplicity in the rail structure. A magnetically levitated (Maglev) unmanned vehicle with SLIM traction, which is powered by a CPS (Contactless Power Supply) can be a high precision delivery solution for this industry. In this paper unmanned FPD-carrying vehicle, which can levitate without contacting the rail structure, is suggested for high clean-class FPD delivery applications. It can be more acceptable for the complex facilities composed with many processes which require longer rails, because of simple rail structure. The test setup consists of a test vehicle and a rounded rail, in which the vehicle can load and unload products at arbitrary position commanded through wireless communications of host computer. The experimental results show that the suggested vehicle and rail have reasonable traction servo and robust electromagnetic suspensions without any contact. The resolution of point servo errors in the SLIM traction system is accomplished under 1mm. The maximum gap error is ${\pm}0.25mm$ with nominal air gap length of 4.0mm in the electromagnetic suspensions. This type of automated delivery vehicle is expected to have significant role in the clean delivery like FPD glass delivery.

• International Journal of Internet, Broadcasting and Communication
• /
• 제14권2호
• /
• pp.79-88
• /
• 2022

Recently, securing stable supply of fresh food is deemed as one of the important tasks. Accordingly, now the presence of cold chain along with the needs of a comfortable and healthy life is growing as the online market expands and the contactless industry grows, however, cold chain is being studied only in the aspect of ground and sea transportation. And, due to global warming and strengthening global environmental regulations, we believe that it is necessary to convert the existing road-centered logistics system into a railway-centered logistics system, a low-carbon transportation means. Therefore, in this paper we calculated the maximum energy required by the reefer container as a basic research necessary for constructing the low temperature distribution and cold chain based on the reefer container railway, and conducted a study on methods of supplying the reefer container power utilizing 1. tramline, 2. battery, 3. generator. The results of this paper can be utilized as a foundational study for building a cold chain based on a reefer container dedicated to freight trains in the future.