• Journal of Power System Engineering
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• 제10권4호
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• pp.165-171
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• 2006

An experiment to observe reduction of pressure fluctuation in the compressing system utilizing snubber has done. The experiment measured pressure at inlet and outlet of snubber. It used an air compressor as a model of hydrogen one. Snubber with buffer and snubber without buffer were used to get comprehensive comparison between both of that snubber. An analysis by using Fast Fourier Transform (FFT) method was conducted to verify working pressure frequency. With this method pure signal of static pressure was filtered from noisy signal. The experiment was run for several speeds of piston movement. It was controlled by adjustable frequency regulator that controled rotation of actuator motor. This was connected to the piston-reciprocating compressor with V-belt. From result obtained, the fluctuation was increasing proportionally when frequency of driver motor was increased.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2004년도 유체기계 연구개발 발표회 논문집
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• pp.697-702
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• 2004

LG Electronics developed linear compressors for a household refrigerator which can reduce energy consumption up to $24\%$ by only Drop-ln instead of a conventional reciprocating compressor. The linear compressor is composed of a linear oscillating motor, a piston directly coupled with the linear motor, a cylinder and the specific discharge system of LG. Because of this free-piston structure, the position of the piston can be changeable according to the voltage variation, load variation and so on. By this reason, LG linear compressor has been in need of an additional unit to control the position of the free-piston stably. In this paper we will introduce the innovative technology which is able to operate the linear compressor without controlling the piston position like a conventional reciprocating compressor.

• The Transactions of The Korean Institute of Electrical Engineers
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• 제56권3호
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• pp.594-599
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• 2007

A dosed-loop sensorless stroke control system for a linear compressor has been designed. The motor parameters are identified as a function of the piston position and the motor current. They are stored in ROM table and used later for the accurate estimation of piston position. Also it was attempted to approximate the identified motor parameters to the 2nd-order surface functions. The 2nd-order surface functions are divided into 2 or 4 sub-sections for more precise identification of motor parameters. Some experimental results are given in order to show the feasibility of the proposed control schemes for linear compressors.

• Proceedings of the KIPE Conference
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• 전력전자학회 2010년도 하계학술대회 논문집
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• pp.438-439
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• 2010

Compressor의 개발 동향은 높은 에너지 효율과 넓은 운전영역의 특성을 갖는 방향으로 성장해 왔다. 특히 기존의 AC Motor를 DC Motor로 대체함으로써 더 높은 효율을 얻을 수 있게 되었다. 본 논문은 압축기의 핵심 부품인 30hp급 용량에 92%의 효율과 3800RPM 가변속 운전이 가능한 BLDC Motor를 맥스웰을 이용하여 시뮬레이션하고 실제 제작을 통해 효율과 가변속 운전을 실험하였다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• 제22권3호
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• pp.34-39
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• 2008

The purpose of this paper is characteristic analysis of multi-disk axial-gap pm motor for turbo compressor. The axial-gap permanent magnet motor has shown a growing interest in high-speed application for its high-efficiency, compact size and low vibration characteristics due to core-less structure. To achieve high-power, the axial-gap PM motor has multi-disk structure of stator and rotor disk. Because of its complicated magnetic flux path, it is not easy to calculate a dynamic characteristics using finite element analysis. In this paper, the simplified 2-D unfolded model to predict EMF characteristic is presented. To verify thesuggested 2-D unfolded model analysis of back-EMF characteristic was calculated and compared 3-D finite element. Finally the proposed method is verified by experimental results and shows good agreement with test results.

• Journal of the Korean Society of Industry Convergence
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• 제27권2_2호
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• pp.325-332
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• 2024

Contemporary power systems demand efficient and sustainable technologies. Single-phase induction motors, while widely used, face efficiency challenges due to inherent rotor losses. Proposed solutions include the Line-start Permanent Magnet Synchronous Motor (LSPMSM), leveraging permanent magnets for enhanced energy density but facing demagnetization and cost issues. Alternatively, the Line-start Synchronous Reluctance Motor (LSRM) operates as a hybrid motor without permanent magnets, reducing rotor losses and potentially improving efficiency. This paper focuses on designing an LSRM rotor for air conditioner compressors, analyzing start-up characteristics and efficiency through finite element analysis. A comparative study with single-phase induction motors provides insights for future motor technology selection, balancing efficiency and other requirements.

• 전기의세계
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• 제26권2호
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• pp.19-20
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• 1977

근래 국민생활수준의 향상에 따라 일반가정에서 필수품으로 애용되고 있는 전기냉장고와 상품용 청량음료, 식품등의 보관에 널리 이요오디는 Show case, ice cream stocker등 냉응용기의 수요가 날로 증대되어 왔고, 이들 제품의 핵심부품인 Compressor의 도입량도 매년 증가되고 있으며 국내가전업계에서 도입하는 부품의 비중으로 볼 때 상당한 부담을 안고있는것으로 간주된다. 당사에서는 그동안 도입에만 의존하던 compressor의 국산화에 착수하여 여러가지 우려곡적을 격은 결과 국산개발을 성공리에 완수하고 제품의 국산화 비율을 높이는 등 여러 측면에서 지대한 성과를 거두었다. 본고에서는 당사의 Compressor국산화 작업에 부수하였던 제반 문제점들을 열거하므로써 국내업계에 조금이나마 도움이 되었으면 한다.

• Transactions of the Korean Society of Mechanical Engineers
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• 제19권8호
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• pp.1964-1971
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• 1995

In the present study, the performance characteristics of a centrifugal air compressor were investigated experimentally. The PC controlled performance test facility for a centrifugal air compressor driven by an electric motor with a gear box to achieve higher compressor rotating speed was set up in the present study. The performance test for a turbocharger compressor of a diesel engine was conducted, and in a case of 34,800 rpm, pressure ratio 1.18, flow rate 0.09kg/s, compressor efficiency 61% were investigated. Adiabatic power for a tested compressor showed maximum value at mass flow ratio 0.8. The value of mass flow ratio of maximum efficiency was about 0.37, it was independent of compressor rotating speed.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2003년도 유체기계 연구개발 발표회 논문집
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• pp.693-696
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• 2003

Hermetic Compressor circulates refrigerant with constant flow rate regardless of operation condition. so, at the operating condition requiring low cooling capacity, too much refrigerant flow deteriorates seasonal energy efficiency ratio(SEER). In this reason, modulated compressor is needed to improve SEER. Among many types of modulated compressor, non-inverter type modulated compressor is required for its low cost and easy to development. In the modulated scroll compressor by bypass method, EER steeply decreases for many loss like re-compression, changes of volume ratio, decrease of motor efficiency by torque variation. So. the range of modulation ratio for optimized SEER must be selected accompany with air conditioner set development.

• Proceedings of the KIEE Conference
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• 대한전기학회 2009년도 춘계학술대회 논문집 에너지변화시스템부문
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• pp.61-63
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• 2009

This paper design a rotor shape of a BLDC motor used for reciprocating compressor. Demagnetization analysis of a basic model is performed by 2D finite element method. This type improved demagnetization characteristics and showed good performance to resist partial demagnetization of ferrite magnet.