• International Journal of Air-Conditioning and Refrigeration
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• 제8권1호
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• pp.29-39
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• 2000

A series of tests were performed to verify the transient characteristics of heat pump in heating and cooling mode when operating speed was varied over the 30 to 102Hz. One of the major issues that has not been addressed so far is transient characteristics during speed modulation. The model for cycle simulation has been developed to predict the cycle performance under conditions of decreasing drive frequency and the results of the theoretical study were compared with the results of the experimental study. The simulated results were in good agreement with the experimental result within 10%. The transient cycle migration of the liquid state refrigerant causes significant dynamic change in system. Thus, the migration of refrigerant was the most important factor whenever do experimental results analysis or develop simulation model.

• 산업기술연구
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• 제30권A호
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• pp.9-15
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• 2010

Recently, Smart Grid is a emerging topic in power and communication industry. Smart Grid refers to a evolution of the electricity supply infrastructure that monitors, protects, and intelligently optimize the operation of the interconnected elements including various type of generators, power grid, building/home automation system and end-use consumers. In order to successful implementation of Smart Grid, energy management function will be the key factor that coordinates and optimally controls the various loads according to the operating condition and environments, and the load patterns in residential and commercial building will be required as fundamental element for load management. In this study, we collects many types of energy usage data of electric appliances, analyze their load curves, and make the general load patterns for electrical appliance.

• 대한전기학회논문지:전력기술부문A
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• 제54권1호
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• pp.31-37
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• 2005

With biological effects by ELF(Extremely Low Frequency) magnetic field generated from power system, the transient magnetic field from electric appliances is a major issue presently. In this paper, we measured magnetic field distributions around electric appliances in view of harmonics and analyzed them by the use of an equivalent magnetic dipole moment method. This method was applied to 19 types of appliances, and their equivalent magnetic dipole moments and harmonic components were determined. The results show that this method is applicable to many appliances and the higher frequency magnetic field may induce higher current inside living bodies.

• 대한전기학회논문지:전력기술부문A
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• 제48권5호
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• pp.487-493
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• 1999

To predict the background level of harmonics produced by household appliances, information on the site, capacity, and usage pattern of these loads arenecessary. However, as household appliances are distributed widely and various in type, it is difficult to know these kinds of information accurately. This paper presents a method for estimation of background level of harmonics produced by distributed harmonic sources with readily available data. Large industrial customers are excluded from this study. In this paper, customers are grouped into three classes, i.e. residential, commercial, and industrial. Typical customers for each class are assumed and characteristics of their equipments are modeled. As the proposed method does not require harmonic measurement, it can be employed to forecast voltage total harmonic distribution (VTHD) in the future. An illustrative example is described.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.848-850
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• 2004

Complex sensorless control scheme is difficult to utilize in field of home appliance system because of cost problem. Therefore, it is necessary to introduce simplified sensorless control scheme that is composed of least calculation to estimate the rotor position. This paper presents the principle of the rotor position estimation with comparison of the estimated flux linkage and reference flux linkage. In order to verify the feasibility of control scheme, simulation with MATLAB and experiment is performed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.1013-1015
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• 2004

SRM (switched reluctance motor) provides an excellent adjustable speed and torque characteristics. SRM has the possibility of maintaining full power over a wide speed range. So, many attempts are being done from home appliances to industrial applications. Especially, a traction drive of an SRM is one of a good application for it's DC-series characteristic. However, because of the switching mechanism and reluctance torque. it has some disadvantage of noise and vibration. It is difficult to adopt to an appliance demanding silency. Performance and noise tests with 6/4 and 12/8 SRM were excuted to compare the characteristics.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 B
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• pp.753-755
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• 2003

The switched reluctance motor(SRM) drive system provides a good adjustable speed and torque characteristics. SRM has the possibility of maintaining full power over a wide speed range. So, many attempts are being done from home appliances to industrial machinery and tools. Especially, a traction drive of an SRM is one of a good application for it's DC-series characteristic. However, because of the switching mechanism, it has some disadvantage of noise and vibration. It is difficult to adopt to an appliance demanding silency. A noise simulation of 6/4 and 12/8 SRM was done in order to compare each other, and the design was done carefully.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 전력전자학술대회 논문집
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• pp.483-486
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• 2001

This Paper the state-of-the art indirect induction heated boiler and induction heated hot air producer using the voltage-fed series resonant high-frequency inverter whice can operate in the frequency range from 20kHz to 50kHz. A specially-designed induction heater composed of laminated stainless assembly with many tiny holes and interconnected spot welding points between stainless plates is inserted into the ceramic type vessel with external working coil connected to the inverter and tubelence fluid through this induction heater in moving fluid generates in the vessel. The operating performances of this unique appliance in next generation and its effectiveness are evaluated and discussed from a practical point of view.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2009년도 춘계학술대회 논문집
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• pp.321-323
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• 2009

When power failure occurs at multi-housing complex, auxiliary generator or emergency generator starts to provide power to households. This power is connected to emergency power ELB(Earth Leakage Breaker) at home distribution panel board and supplies power only for emergency light in living room but for heating system, refrigerator and other inevitable apparatuses that are in need of uninterruptible power. Since those domestic appliance are fed from common power line, they are inoperable during power failure. Our research is to resolve this problem by developing compatible relay-drive common/emergency-power ATS (automatic transfer switch) for home distribution panel board. In case of power failure, it transfers automatically and commences to provide power from emergency generator. Through this, Consumers can reach satisfaction where common power loads operate without any problem under both ordinary and power failure condition.

• 조명전기설비학회논문지
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• 제29권5호
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• pp.41-49
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• 2015

In this paper, we studied an optimal design and efficiency improvement of the BLCD motor used in home electronic appliance. The number of stator slots is chosen depending on the rotor poles, phase number, and the winding configuration. In general, a fractional slots/pole design is preferred to minimize cogging torque. To reduce the winding resistance, we reduced the coil length and we improved the coil space factor. We proposed three types of stator slot shape design for the optimal BLDC motor design. One of them, U-type slot shape is a best optimal design, it proved by the simulated and tested. Optimal design of essential parameters aiming at high winding factor are presented to create for a high-quality system implementation. Design analysis is verified by testing and building a prototype motor.