• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.125-128
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• 2006

This paper presents a novel type soft switching PWM power frequency AC-AC converter using bidirectional active switches or single phase utility frequency AC-high frequency AC matrix converter. This converter can directly convert utility frequency AC (UFAC, 50Hz/60Hz) power to high frequency AC (HFAC) power ranging more than 20kHz up to 100kHz. A novel soft switching PWM prototype of high frequency multi-resonant PWM controlled UFAC-HFAC matrix converter using antiparallel one-chip reverse blocking IGBTs manufactured by IXYS corp. is based on the soft switching resonance with asymmetrical duty cycle PWM strategy. This single phase UFAC-HFAC matrix converter has some remarkable features as electrolytic capacitor DC busline linkless topology, unity power factor correction and sine-wave line current shaping, simple configuration with minimum circuit components, high efficiency and downsizing. This series load resonant UFAC-HFAC matrix converter, incorporating bidirectional active power switches is developed and implemented for high efficiency consumer induction heated food cooking appliances in home uses and business-uses. Its operating performances as soft switching operating ranges and high frequency effective power regulation characteristics are illustrated and discussed on the basis of simulation and experimental results.

• 전기학회논문지
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• 제58권8호
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• pp.1532-1537
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• 2009

Nowadays the diversity and large-capacity of electric appliances are strong effect on electrical fires augment in an alarming way. But, as the inactive response characteristics of the existing RCD (Residual Current protective Device) used on low voltage power distribution lines, so control of overload and electric short circuit faults, major causes of electrical fires, are not enough. Therefore this paper is confirmed the unreliability of the existing RCD by electrical faults simulation and is proposed a auxiliary trip device of RCD by using a high precision current sensor (namely, reed switch) for the prevention of electrical disasters in low voltage power distribution lines caused by overload or electric short circuit faults. The sensitive reed switch in the proposed ATD (auxiliary trip device) exactly detects the increased magnetic flux with the overload or the short current caused by a number of electrical faults, and then rapidly cuts off the existing RCD. The proposed auxiliary trip device of RCD is confirmed the excellent characteristics in response velocity and accuracy in comparison with the conventional circuit breaker through various operation performance analysis. The proposed ATD can also prevent electrical disaster, like as electrical fires, which resulted from the malfunction and inactive response characteristics of the existing RCD.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.1047-1050
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• 1998

This paper describes an advanced prototype of voltage-fed zero voltage soft-switching PWM resonant inverter with an active voltage clamped capacitor, which is put into practice for high-frequency high-power induction-heated appliances. This application-specific quasi-resonant inverter using the latest generation IGBTs for soft-switching can regulate its output power under a principle of a fixed frequency ZVS-PWM strategy. Its operating principle and unique features are presented as compared with a conventional quasi-resonant ZVS inverter for induction-heated cooker, together with its power regulation characteristics on the basis of its simulation and experimental results. The steady-state performances of this inverter developed for multi-burner type induction-heated food cooking appliance are evaluated and discussed from a practical point of view.

• 한국주거학회논문집
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• 제22권6호
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• pp.31-42
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• 2011

The purpose of the study was to investigate the characteristics of energy use behaviors and energy saving consciousness of multi-family housing residents. The energy referred to in this study includes electric energy, heating energy and water usage. This study was conducted from a survey carried out in Seoul and Gyeonggi-do. The results of the study are as follows: First, among the survey questions, the only positive energy saving behaviors shown by the occupants was turning off the lights and the television, and in the use of kitchen appliances; it could therefore be concluded that, in general, energy saving attitude and consciousness were not sufficient to reduce energy consumption. Second, the results showed high mean scores for the behaviors which were easy to control, such as turning off lights and televisions, and low mean scores for the behaviors which required extra effort to completely cut off electricity energy such as pulling out the plugs of electronic appliances. Third, it was found that the occupants generally showed the tendency to save heating energy. However, in cases where the occupants were required to continuously and directly experience indoor temperatures, they expressed passive attitudes toward saving energy. Fourth, they showed wasteful attitudes toward water usage by leaving the tap running when taking showers and washing their faces. Fifth, while they showed a strong energy saving consciousness, they also showed a passive attitude about putting this into practice; there was therefore some gap between attitude and behavior. Lastly, among the socio-demographic factors, age and family lifecycle were very important factors affecting energy use and energy saving consciousness.

• 한국자동차공학회논문집
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• 제20권1호
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• pp.28-38
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• 2012

The characteristics of vibration and noise of a compressor used for electric appliances have significant influence on the quality of the products. For improvement on the quality of electric appliances, investigations for understanding the dynamic behaviour of the compressor are essential. Since Virtual Lab for the dynamics model and MAXWELL for the electromagnetics model are separate software programs with no interface, the joint simulation of the models could not be performed. This study suggests a way to develop the compressor model capable of the joint simulation with MATLAB/SIMULINK linking a flexible multi-body dynamics model, a torque model, and an electricity control model. The compressor model is found to be able to perform I/O data transfer among the sub-models and joint simulation. The simulation results of the flexible body and rigid body dynamics models were compared to check availability of the joint simulation system. In addition, the simulated vibration and driving torque of the compressor mechanisms were compared with measurements. Through the simulations, the influence of springs and LDT on the dynamic behaviour of the compressor was examined. This study examines the influence of the dynamic behaviour of the compressor mechanisms through joint simulation of the flexible multi-body dynamics model and electromagnetic circuit allows analysis.

• 한국정보통신학회논문지
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• 제9권7호
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• pp.1445-1451
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• 2005

홈 네트워크란 일반적으로 PC를 비롯한 가정 내의 가전기기들이 하나의 네트워크로 통합되어 통신이 가능하도록 하는 것을 의미한다. 21세기에 들어서 홈 네트워크 환경을 위한 여러 가지 기술들이 제시되었다. 대표적으로 HomePNA, IEEE1394, ethernet lan, 블루투스 등이 있다. 일반적으로 홈 네트워크를 구현하는데 있어 가전기기간 데이터를 전송 할 경우 표준 직렬 인터페이스인 RS232를 이용한다. 그러나 RS232를 이용하여 홈 네트워크를 구현할 경우 다음과 같은 문제점이 있다. 즉, point-to-point 방식을 사용하여 각각의 기기를 모두 RS232로 연결해야 한다는 것이다. 이를 경우 기기의 숫자만큼 회선이 늘어남으로 인해 시스템 자체가 복잡해지고 비용도 증가한다. 이러한 문제점을 개선하고자 이 논문에서는 RS422 Multi-drop mode 시리얼 통신를 이용하여 흠 네트워크를 설계하였고 임베디드 리눅스 시스템으로 제어하였다. 그리고 홈 네트워크 가상환경을 구현하기 위해서 PIC를 이용하여 모터 및 센서를 RS422와 연결하였다.

• 산업경영시스템학회지
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• 제32권1호
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• pp.137-146
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• 2009

Researches on after-sales quality have centered on home electric appliances, figuring out how factors influencing after-sales service quality are causally related to customer's behavioral intentions, via consumer satisfaction as an intermediary parameter In most cases of after-sales service in home electric appliances, upon customer's request, service agents make a visit to where the appliance is installed, and check the product and do repairs. However, in case of a small portable device such as a cell phone, which people carry around at all times, most of the times customers themselves show up at the after-sales center, and demand a check-up and repairs. The main difference here is that the after-sales services are provided when a product can no longer perform its basic function and customer dissatisfaction is already up. In this case, the basic function of a product corresponds to must-be factor according to Kano model. The goal of our research is to identify critical factors for effective and efficient after-sales service, and how to monitor them on a routine basis. In our research, the quality after-sales service consists of three dimensions, interactive quality, result quality, and physical environment quality. We set up variables for each dimension, which would measure from customer's perspective key determining factors in service delivery process. Instead of focusing on customer satisfaction aspect, we focused on how after-sales service factors contribute to addressing customer complaints. Additionally, our future research would aim to verify how customer's behavioral intentions are affected, as the resolution of consumer complaints becomes more successful when adjustment of relevant quality factors improves after-sales service quality.

• 상하수도학회지
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• 제25권5호
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• pp.691-697
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• 2011

In this study, by using the Water footprint technique, the water consumption by washing machines, which holds higher ranks in using water than any other electric appliances, was analyzed during their life cycle. The life cycle is defined as raw materials production step, manufacturing step, and using step. In raw materials production step, Input materials were researched by using LCI DB(Life Cycle Inventory Database) and the water consumption was calculated with consideration of approximately 65% Input materials which were based weight. In manufacturing step, the water consumption was calculated by the amount of energy used in assembly factories and components subcontractors and emission factor of energy. In using step, referring to guidelines on carbon footprint labeling, the life cycle is applied as 5 years for a washing machine and 218 cycles for annual bounds of usage. The water and power consumption for operating was calculated by referring to posted materials on the manufacture's websites. The water consumption by nation unit was calculated with the result of water consumption by a unit of washing machine. As a result, it shows that water consumption per life cycle s 110,105 kg/unit. The water consumption of each step is 90,495 kg/unit for using, 18,603 kg for raw materials production and 1,006 kg/unit for manufacturing, which apparently shows that the using step consume the most water resource. The water consumption by nation unit is 371,269,584tons in total based on 2006, 83,385,649 tons in both steps of raw material production and manufacturing, and 287,883,935 tons in using step.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2005년도 추계종합학술대회
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• pp.512-516
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• 2005

홈 네트워크란 일반적으로 PC를 비롯한 가정 내의 가전기기들이 하나의 네트워크로 통합되어 통신이 가능하도록 하는 것을 의미한다. 21세기에 들어서 홈 네트워크 환경을 위한 여러 가지 기술들이 제시되었다. 대표적으로 HomePNA, IEEE1394, ethernet lan, 블루투스 등이 있다. 일반적으로 홈 네트워크를 구현하는데 있어 가전기기간 데이터를 전송 할 경우 표준 직렬 인터페이스인 RS232를 이용한다. 그러나 RS232를 이용하여 홈 네트워크를 구현할 경우 다음과 같은 문제점이 있다. 즉, point-to-point 방식을 사용하여 각각의 기기를 모두 RS232로 연결해야 한다는 것이다. 이를 경우 기기의 숫자만큼 회선이 늘어남으로 인해 시스템 자체가 복잡해지고 비용도 증가한다. 이러한 문제점을 개선하고자 이 논문에서는 RS422 Multi-drop mode 시리얼 통신을 이용하여 홈 네트워크를 설계하였고 임베디드 리눅스 시스템으로 제어하였다. 그리고 홈 네트워크 가상환경을 구현하기 위해서 PIC를 이용하여 모터 및 센서를 RS422와 연결하였다.

• 전기학회논문지
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• 제64권5호
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• pp.779-785
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• 2015

Recently, home energy management system (HEMS) for power consumption reduction has been widely used and studied. The HEMS performs electric power consumption control for the indoor electric device connected to the HEMS. However, a traditional HEMS is used for passive control method using some particular power saving devices. Disadvantages with this traditional HEMS is that these power saving devices should be newly installed to build HEMS environment instead of existing home appliances. Therefore, an HEMS, which performs with existing home appliances, is needed to prevent additional expenses due to the purchase of state-of-the-art devices. In this paper, an intelligent inference algorithm for EMS at home for non-power saving electronic equipment, called legacy devices, is proposed. The algorithm is based on the adaptive network fuzzy inference system (ANFIS) and has a subsystem that notifies retraining schedule to the ANFIS to increase the inference performance. This paper discusses the overview and the architecture of the system, especially in terms of the retraining schedule. In addition, the comparison results show that the proposed algorithm is more accurate than the classic ANFIS-based EMS system.