• Journal of Power Electronics
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• 제12권6호
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• pp.954-959
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• 2012

A hybrid switch that uses a microelectromechanical system (MEMS) switch as a gate driver of a MOSFET is applied to an energy harvesting system. The power management circuit adopting the hybrid switch provides ultralow leakage, self-referencing, and high current handling capability. Measurements show that solar energy harvester circuit utilizing the MEMS-MOSFET hybrid switch accumulates energy and charges a battery or drive a resistive load without any constant power supply and reference voltage. The leakage current during energy accumulation is less than 10 pA. The power management circuit adopting the proposed hybrid switch is believed to be an ideal solution to self-powered wireless sensor nodes in smart grid systems.

• KEPCO Journal on Electric Power and Energy
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• 제7권1호
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• pp.73-77
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• 2021

As the big data analysis technologies has been developed worldwide, the importance of asset management for electric power facilities based data analysis is increasing. It is essential to secure quality of data that will determine the performance of the RISK evaluation algorithm for asset management. To improve reliability of asset management, asset data must be preprocessed. In particular, the process of cleaning dirty data is required, and it is also urgent to develop an algorithm to reduce time and improve accuracy for data treatment. In this paper, the result of the development of an automatic cleaning algorithm specialized in overhead transmission asset data is presented. A data cleaning algorithm was developed to enable data clean by analyzing quality and overall pattern of raw data.

• 전기학회논문지P
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• 제67권2호
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• pp.70-74
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• 2018

Social infrastructure such as production, transportation, gas, and electrical facilities would be degraded according to time and those facilities might need more maintenances, repairing, and management as time goes by. Especially, in the case of a power transformer, it is important to diagnose the transformer in order to avoid malfunction and failure because they could cause enormous damage. The economic as well as technical aspects of a transformer management must be considered while it is operated. Therefore, the concept of asset management should be applied as an advanced method of transformer management. Asset management refers to a series of processes to make a plan of maintenance and conservation of a power transformer considering the soundness, investment cost, and importance of equipment. It is important to apply the asset management considering calculation of a lifetime loss. In this paper, the lifetime loss calculation method of asset management for a power transformer is suggested.

• 한국안전학회지
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• 제37권6호
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• pp.50-59
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• 2022

In the Construction Technology Promotion Act (CTPA) of the Republic of Korea, safety management cost is enforced as a statutory cost that must be included in the budget of construction projects. However, the construction of underground electric power transmission facilities (UEPTFs) is not included in the category of construction works defined in the CTPA. Consequently, the statutory safety management cost does not apply to the construction of UEPTFs. To overcome this limitation, the clients of UEPTF construction projects generally provide internal guidelines enabling the addition of the safety management cost in the project budget. Nevertheless, even after the execution of the internal guidelines, some important cost items are omitted from the budget owing to the incompleteness of the guidelines. In this context, this paper proposes a complete set of accounting items and their calculation methods for appropriate budgeting of the safety management cost of UEPTF construction projects. To this end, the current budgeting method of the safety management cost of UEPTF construction projects is analyzed, and a questionnaire study is performed to confirm the necessary cost items and their appropriate calculation methods. Based on the results of the questionnaire study, a set of accounting items and their calculation criteria for the budgeting of the safety management cost of UEPTF construction projects are proposed.

• 전기학회논문지
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• 제57권6호
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• pp.1032-1035
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• 2008

In this paper, a DC power management scheme is proposed for efficient battery operation of 60-GHz receivers. It consists of a rectenna and a zero-cross detector. The harmonic rejection capability of a circular sector antenna is used to simplify the rectenna. The zero-cross detector is introduced to increase sensitivity. When the received power density is larger than 0.013 $mW/cm^2$, it can generate enough DC power to activate an RF receiver. Experimental data is used to verify the proposed idea.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.975-980
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• 1993

In accordance with increase, if electronic power demanded, more efficient supervisory control of distribution system will be required. This study contains development of MMI(man-machine-interface) system with GUI(graphic-user-interface), for the automatic power distribution system. The main function of MMI system is to edit network of power distribution and to management of data base for network. The GUI function of MMI system enables more efficient management of power distribution system.

• 디지털산업정보학회논문지
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• 제9권3호
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• pp.49-57
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• 2013

Power-saving PC software enables the inexpensive power control, but the installation of the power-saving software in all computers in the organization is not an easy task. Computer users in the organization are usually not cooperative as they do not think the power-saving cost is directly related to themselves. The PC power-saving system provides advantage to driving active participation in which users installs the power saving software by restricting IP address through the power management server. However, the problem with this approach is the security vulnerability to IP spoofing attacks, therefore we need to solve the problem that disrupt the entire network system rather than saving electric power. This paper proposes the security authentication system that can implement the efficiency saving power by providing high security for the members' computer system of the public institutions based on the PC power-saving system. Also, by analyzing it in comparison with other method, it is possible to check that the prospects of safety and efficiency are strengthened.

• 마이크로전자및패키징학회지
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• 제21권2호
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• pp.13-21
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• 2014

Technology for high power devices has made impressive progress in increasing the current density of power semiconductor, system module, and design optimization, which realize high power systems with heterogeneous functional integration. Depending on the performance development of high power semiconductor, packaging technology of high power device is urgently required for efficiency improvement of the device. Power device packaging must provide superior thermal management due to high operating temperature of power modules. Here we, therefore, review critical challenges of typical power electronics packaging today including core assembly processes, component materials, and reliability evaluation regulations.

• 한국항행학회논문지
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• 제17권6호
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• pp.609-615
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• 2013

어떤 선박에서도 마찬가지로 적정한 전력의 공급은 매우 중요하며, 육지와 거리가 먼 대양 운항 선박에서는 특히 더욱 중요하다. 이와 같이 운항 중인 선박의 전력 공급 시스템의 효율성과 경제성 측면의 문제를 해결하기 위해서 본 논문에서는 선박에서의 전력공급을 지능적으로 제어하는 전력관리 시스템을 제안한다. 본 설계에서의 전력관리 시스템은 부하전력 감지 시스템, 발전기 제어 시스템, 그리고 전력 모니터링 시스템으로 각각 구성된다. 부하전력 감지 시스템에서는 CT 및 PT 센서를 이용하여 전류와 전력량을 측정하며, 그리고 발전기 제어 시스템에서는 여러 가지 다양한 센서로 부터의 취합정보를 이용하여 주/부 발전기를 On/Off 하게 된다. 마지막으로 모니터링 시스템은 부하 전력 감지 시스템과 발전기 관리 시스템에서 수집된 정보를 사용자가 한눈에 알아볼 수 있게 상태 정보를 출력한다. 본 논문에서 구현된 전력관리 시스템은 실시간 실험을 통해서 설계된 바와 같이 잘 작동하는 것을 확인하였으며, 그리고 공인 인증기관으로부터 KSCIEC61892-1:2012 및 KSCIEC60950-1:2008 인증을 획득하였다.

• 한국인터넷방송통신학회논문지
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• 제12권4호
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• pp.103-109
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• 2012

본 논문은 현재 급격히 증가하는 전력을 효율적으로 관리하고 낭비를 최소화하기 위한 전력 관리 시스템을 제안한다. 기업, 공장, 관공서, 학교 등의 환경에 최적화된 USN(Ubiquitous Sensor Network)을 기반으로 한 산업용 전력관리시스템을 구현하였다. 콘센트에 직접 부착하여 전력량 측정 및 전력제어가 가능하다. 전력센서를 PLC(Power Line Communication)와 TCP/IP 통신을 통하여 하나의 네트워크로 구성하고 전력을 감시 및 제어한다. 수집된 데이터를 기반으로 전력을 효율적으로 유지관리 할 수 있으며, 또한 안드로이드 기반 앱을 통하여 언제 어디서나 서버에 접속하여 전력량을 관리하고 낭비되는 전력을 효율적으로 관리할 수 있는 시스템을 구현하였다.