• 전력전자학회논문지
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• 제27권5호
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• pp.376-383
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• 2022

The improved performance of computer parts, such as graphic card, CPU, and main board, has led to the need for power supplies with a high power output. The dynamic load profile rapidly changes the usage of power consumption depending on load operations, such as PC power and air conditioner. Under dynamic load profile conditions, power consumption can be classified into maximum, normal, and standby power. Several problems arise in the case of maximum power. Peak power is generated at the system power source in the maximum-power situation. Frequent generation of peak power can cause high-frequency problems and reduce the life of high-pressure parts (especially high-pressure capacitors). For example, when a plurality of PCs are used, system overload occurs due to peak power generation and causes problems, such as power failure and increase in electricity bills due to exceeded contract power. To solve this problem, a system peak power limit/compensation power circuit is proposed for a power supply under dynamic load profile conditions. The proposed circuit detects the system current to determine the power situation of the load. When the system current is higher than the set level, the circuit recognizes that the system current generates peak power and compensates for the load power through a converter using a super capacitor as the power source. Thus, the peak power of loads with a dynamic load profile is limited and compensated for, and problems, such as high-frequency issues, are solved. In addition, the life of high-pressure parts is increased.

• 전기학회논문지P
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• 제52권2호
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• pp.85-90
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• 2003

This paper has presented the efficient implementation of MPEG-4 simple profile video decoder, which is used as video compression standard in mobile video communication. We have used the ARM9 processor in implementing this MPEG-4 simple profile, which requires much processing power and low power implementation. At first we implemented with C-language under the PC environment with ADS(ARM Developer Suite) environment, and then we have tried to reduce a clock cycle for a power consumption optimization through conversion an assembly language for C-code partly. We have verified the processor is operated at 22.47MHz operation after optimization, but 148MHz before optimization.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(2)
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• pp.677-681
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• 2004

This paper presents the design and implementation of a low-profile power supply developed for AC-PDP application systems. In the proposed power supply, planar magnetics and SMD devices are integrated into advanced power conversion techniques to implement a low-profile power supply applicable to most AC-PDP application systems. Engineering details on the design and fabrication of planar magnetic components are presented. The performance of the prototype power supply is also demonstrated to validate the application potentials of the proposed power supply.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2000년도 Proceedings of 5th International Joint Symposium on Microeletronics and Packaging
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• pp.97-102
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• 2000

We have studied etching characteristic of Ta film using Electron Cyclotron Resonance (ECR) etcher system. Microwave source power. RF bias power. and working pressure were varied to investigate the etch Profile. And we have used two step etching method to acquire the goWe have studied etching characteristic of Ta film using Electron Cyclotron Resonance (ECR) etcher system. Microwave source power. RF bias power. and working pressure were varied to investigate the etch Profile. And we have used two step etching method to acquire the good etch profile preventing the microloading effect.od etch profile preventing the microloading effect.

• 한국정밀공학회지
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• 제24권1호
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• pp.37-46
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• 2007

The vibration environment essentially companied by vehicle operation on the ground is determined by the shape of road surface, which is called profile. This paper focuses on development of a profile and severity measurement system for unpaved test courses. In general, the profile and severity of unpaved road is an important issue in the reliability of endurance test. In order to measure unpaved road profile and severity, it is necessary to develop a profilometer system. The developed profilometer system is composed of data processing computer, power unit, air compressor and sensors(encoder, vertical gyro and laser displacement) This paper presents the measuring system configuration, measurement principle of road profile and analysis method of road characteristics used at CPG(Changwon Proving Ground) for this purpose.

• 제어로봇시스템학회논문지
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• 제10권2호
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• pp.164-170
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• 2004

Recently, the demand for micro hard disk drive that provides high-capacity removable storage for handhold electronic devices is growing very rapidly Reducing power consumption is one of the primary control objectives in micro disk drives. The input power delivered to the seek servo system is consumed as heat by the transistors of power amplifier and motor coil resistance. In this paper, we present a new seek servo controller for minimizing the power consumption. We use a Fourier decomposition and nonlinear programming to determine the optimum seek profile that minimizes the power consumption. Also, the trajectory tracking controller is developed for exact tracking of the optimum seek profile. Finally, we present some experimental results using a commercially available micro disk drive in order to demonstrate the superior performance of the proposed controller.

• 융복합기술연구소 논문집
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• 제5권1호
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• pp.19-22
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• 2015

Human powered aircraft (HPA) is an airplane that uses only human power for its propulsion. The human power as a power resource and an engine produce the available power that is very crucial to the success of the HPA. In the present paper, the human power characteristics for completing the mission profile are discussed focusing on the take-off and climbing performance. The mission profile is designed by using an athlete's power generation. It is believed that present analysis can be helpful for the mission profile design and athletes exercise program development for the HPA competitions.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1379-1383
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• 2005

Introducing the market into the electricity industry lets the multiple participants get into new competition. These multiple participants of the market need new business strategies for providing value added services to customer. Therefore they need the accurate customer information about the electricity demand. Demand characteristic is the most important one for analyzing customer information. In this study load profile data, which can be collected through the Automatic Meter Reading System, are analyzed for getting demand patterns of customer. The load profile data include electricity demand in 15 minutes interval. An algorithm for clustering similar demand patterns is developed using the load profile data. As results of classification, customers are separated into several groups. And the representative curves for the groups are generated. The number of groups is automatically generated. And it depends on the threshold value for distance to separate groups. The demand characteristics of the groups are discussed. Also, the compositions of demand contracts and standard industrial classification in each group are presented. It is expected that the classified curves will be used for tariff design, load forecasting, load management and so on. Also it will be a good infrastructure for making a value added service related to electricity.

• 전기전자학회논문지
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• 제23권1호
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• pp.224-229
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• 2019

시트는 운전 중에 운전자와 승차자의 편의를 제공하도록 요구된다. 최근 수동으로 동작하는 시트가 모터를 이용하여 자동으로 동작하는 전동 시트로 변화되고 있다. 시트에 모터를 적용함에 따라 과전류에 의해 발생하는 반전충격음, 진동 및 소음과 같은 문제가 발생하고 있다. 시트 모터의 제어를 통해 문제를 해결하려는 연구가 시도 되고 있다. 본 연구에서는 전동 시트에 사용되는 DC 모터에 흐르는 전류가 소프트 스타트와 소프트 스톱 형태를 갖도록 입력 전압의 형상을 결정하는 4개의 제어변수를 제어하는 기술 제안하였다. 전동 시트의 모델링을 통해 입력 전압에 대한 코일에 흐르는 전류의 관계식을 유도하고, 제어변수에 따른 시뮬레이션을 통해 소프트 스타트와 소프트 스톱 형태를 갖는 최적의 전류 형상의 구현이 가능함을 확인하였다.

• Journal of Electrical Engineering and Technology
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• 제8권2호
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• pp.244-251
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• 2013

This paper presents a study the change of the load profile on the power system by the charging impact of electric vehicles (EVs) in 2020. The impact of charging EVs on the load demand is determined not only by the number of EVs in usage pattern, but also by the number of EVs being charged at once. The charging load is determined on an hourly basis using the number of the EVs based on different scenarios considering battery size, model, the use of vehicles, charging at home or work, and the method of charging, which is either fast or slow. Focusing on the impact of future load profile in Korea with EVs reaching up 10 and 20 percentage, increased power demand by EVs charging is analyzed. Also, this paper analyzes the impact of a time-of-use (TOU) tariff system on the charging of EVs in Korea. The results demonstrate how the penetration of EVs increases the load profile and decreases charging demand by TOU tariff system on the future power system.