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Optimal Design of Single-Phase Line-Start Permanent Magnet Synchronous Motor by using Design of Experiment (실험계획법을 이용한 단상 유도형 동기전동기의 최적 설계)

  • Kim, Seung-Joo;Jung, Dae-Sung;Lee, Chul-Kyu;Lee, Hyung-Woo;Lee, Ju;Oh, Se-Young
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.4
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    • pp.699-704
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    • 2007
  • In this paper, optimized model was designed for the starting characteristic of the Single-Phase Line-Start Permanent Magnet Synchronous Motor by using the Design of Experiment. A field pole angle, thickness and distance from center axis of permanent magnet were selected as design factor. We executed the transient state characteristic analysis of 8 test models. The transient state characteristic analysis was executed by using the 2 dimensional Finite Element Method and the Time Difference Method. We checked the fact that the selected design factor affected starting characteristic of the Line-Start Permanent Magnet Synchronous Motor. Depend on this result we found the optimized design point by using the response optimization.

Nano-tribology of laser textured hard disk by contact start/stop test (CSS test에 의한 레이저 텍스쳐 디스크의 나노-트라이볼로지)

  • Kim, Woo-Seok;Hwang, Pyung;Kim, Jang-Kyo
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.1589-1595
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    • 2000
  • 레이저 텍스쳐와 미케니칼 텍스쳐 컴퓨터 하드디스크의 마찰과 마코 매카니즘이 Contact Start/Stop test 실행후의 특성들에 대해 연구되었다. 다양한 분석적이고 기계적인 테스트 기술들이 이용되었다. 형상, 조도, 화학적 조성, 기계적 성질, CSS 로부터 기인된 코팅의 마찰특성들에 대해 그 변화들을 조사하였다. 즉, AFM(Atomic Force Microscopy), Nano-Indentation, Nano-Scratch, TOF-SIMS(Time of Flight Secondary Ion Mass Spectroscopy), AES(Auger Electronic Spectroscopy)등이 이 연구에 적용되었다. 레이저 텍스쳐 범프의 표면조도와 미케니칼 텍스쳐 지역의 표면조도는 각각 대략적으로 4nm 와 7nm 감소되었다. 탄성계수와 경도값은 CSS test후에 증가하였고 가장 바깥쪽의 코팅층의 변형강화가 생겨났다. 자성층과 Ni-P 층 사이에 점착성의 문제가 확인되었다. TOF-SIMS 분석은 C 와 $C_2F_5$의 세기에 있어서 감소를 드러냈고 이것은 코팅 표면에 윤활제 요소의 마모를 확실시 할수 있는 결과로 나타났다.

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Comparison of Dynamic Characteristics of the tine Start Permanent Magnet Motor and the Induction Motor

  • Yang, Byoung-Yull;Kwon, Byung-Il;Lee, Chul-Kyu;Woo, Kyung-Il;Kim, Byung-Taek
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • v.2B no.3
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    • pp.90-94
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    • 2002
  • The line start permanent magnet (LSPM) motor has been developed facilitate to the design of the synchronous motor. The rotor of this motor is composed of interior permanent magnets and aluminum bars instead of rotor windings. It is difficult to predict the performance characteristics accurately, because many characteristics are produced by the aluminum rotor bars and the permanent magnets. Therefore, in this paper the dynamic characteristics of the LSPM motor are described and compared via the time-stepped finite element method with those of the cage-type induction motor to find the characteristics of the permanent magnets and the rotor bars in the LSPM motor.

Longitudinal Tension Control at Start and Stop in a Multi-span Continuous Process System (변속시의 멀티 스팬 연속 공정 시스템의 장력제어)

  • 신기현;권순오
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1994.10a
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    • pp.584-589
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    • 1994
  • A time-varying nonlinear mathematical model was derived to consider the effect of change in roll radius on tension varation during winding and unwinding. A variable-gain PID controller was designed for tension control at start and stop in a multi-span continuous process system. The controller gains are updated at every control loop as roll radii continuously change. Computer simulation was carried out by using the mathematical model and the controller developed for a typical operating condition including acceleration and deceleration. When the variable-gain PID controller was used, the tension control performance was improved compared with that of existing control method during start-up and stop.

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Design of Single-Phase Line-Start Permanent Magnet Motor Using Equivalent Circuit Method

  • Kwon, Sun-Hyo;Lee, Chul-Kyu;Kwon, Byung-Il
    • Journal of Electrical Engineering and Technology
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    • v.1 no.4
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    • pp.490-495
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    • 2006
  • In this research, the design procedure and the design method of a single-phase line-start permanent magnet motor (LSPM) are proposed. In the design procedure, the permanent magnet is designed first and the windings and capacitors are designed later. As well, the points of design of each design parameter are explained. In the design of the single-phase LSPM, the equivalent circuit method is combined with the finite element method (FEM) because it has a shorter analysis time than FEM. The 400 watts single-phase LSPM is designed and manufactured. The characteristics of the manufactured single-phase LSPM are analyzed and experimented. From the analysis result and the experiment result, it is verified that the design procedure and the design method of the single-phase LSPM is valid.

Dynamic Characteristic Analysis of Single-Phase Line-Start Permanent Magnet Synchronous Motor by Parameter Variation (단상 유도형 동기전동기의 파라미터 변화에 따른 동특성 해석)

  • Oh, Se-Young;Jung, Dae-Sung;Lim, Seung-Bin;Lee, Ju
    • Proceedings of the KIEE Conference
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    • 2006.07b
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    • pp.763-764
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    • 2006
  • In this paper, optimized model was designed for the starting characteristic of the Single-Phase Line-Start Permanent Magnet Synchronous Motor by using the Design of Experiment. A field pole angle, thickness and distance from center axis of permanent magnet were selected as design factor. We executed the transient state characteristic analysis of 8 test models. The transient state characteristic analysis was executed by using the 2 dimensional Finite Element Method and the Time Difference Method. We checked the fact that the selected design factor affected starting characteristic of the Line-Start Permanent Magnet Synchronous Motor. Depend on this result we found the optimized design point by using the response optimization.

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Novel Soft Starting Algorithm of Single Phase Induction Motors by Using PWM Inverter

  • Kim, Hae-Jin;Hwang, Seon-Hwan;Kim, Jang-Mok
    • Journal of Power Electronics
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    • v.18 no.6
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    • pp.1720-1728
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    • 2018
  • This paper proposes a novel soft starting algorithm by using PWM inverter technique to control an amplitude of the motor starting current at a single-phase induction motor (SPIM). Traditional SPIM starting methods such as a Split-Phase, Capacitor-Start, Permanent-Split Capacitor (PSC), Capacitor-Start Capacitor-Run (CSCR), basically cannot control the magnitude of starting current due to the fixed system structures. Therefore, in this paper, a soft starting algorithm based on a proportional resonant (PR) control with a variable and constant frequency is proposed to reduce the inrush current and starting up time. In addition, a transition algorithm for operation modes is devised to generate a constant voltage and constant frequency (CVCF). The validity and effectiveness of the proposed soft starting method and transition algorithm are verified through experimental results.

A Study on the Start-up of the Water/Steam Receiver for Solar Power Tower (타워형 태양열 흡수기의 시동특성에 관한 연구)

  • Seo, Ho-Young;Kim, Jong-Kyu;Kang, Yong-Heack
    • 한국신재생에너지학회:학술대회논문집
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    • 2008.05a
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    • pp.157-160
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    • 2008
  • Solar receiver in the solar power tower system has a similarity to a boiler of the thermal power plant in many aspects. However Boiler is operated long time without stopping while solar receiver repeats start and stop every day. The objective of this study is to investigate start-up characteristics of solar receiver. The experimental device was constructed in a bench scale. Basic experimental condition of water/steam was set by 25 bar and $223^{\circ}C$. Initially, the heat was added into risers only, then another experiment with input into drum additionally was done. When the heat flux was valid only risers, it took about 300 minutes until the water temperature in drum reached $223^{\circ}C$. Water temperature of drum was increased by $44^{\circ}C$/hr with 91.14 g/s of water circulation. With additional heat input into drum, 200 minutes was required to reach $223^{\circ}C$. In this case temperature was increased $66^{\circ}C$/hr with 96.5 g/s of water circulation.

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Analysis of Start-up Characteristics of a Heat Recovery Steam Generator Considering Thermal Constraints (열적 제한요소를 고려한 열회수 증기발생기의 시동 특성 해석)

  • Kim, Young Il;Kim, Tong Seop;Kim, Jae Hwan;Ro, Sung Tack;Kauh, Sang Ken
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.23 no.11
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    • pp.1410-1417
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    • 1999
  • A thorough understanding of the transient behavior during start-up is essential in the design and operation of the heat recovery steam generator(HRSG). During this period of time, material that is exposed to high temperature and experiences a large temperature variation is subject to high thermal stress. In this work, a transient formulation of the HRSG is constructed including the estimation of the thermal stress and fatigue of the drum wall. Start-up behavior of a single-pressure HRSG is analyzed and the effect of bypassing part of the gas turbine exhaust flow on the thermal stress evolution is examined. It is found that the modulation of the gas flow rate using a bypass damper is very useful in view of reducing the thermal stress of the drum and ensuring the fatigue lifetime.

A Qualitative Case Study on the Success of Fashion Retail Start-up by Young Entrepreneurs (청년 창업가의 패션소매 창업 성공에 관한 질적 사례연구)

  • Oh, Hyun Jeong
    • Journal of the Korean Society of Clothing and Textiles
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    • v.42 no.1
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    • pp.133-147
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    • 2018
  • This study examines the experience structure and success theme in the business experience of successful young entrepreneurs in the fashion field. The study was conducted as a qualitative case study. The participants were three CEOs with more than 10 years fashion businesses experience with small and medium enterprises. Data were collected from July 2016 to June 2017 through in-depth interviews in Seoul and Gwangju as well as literature collected from other journals, newspaper articles, and books. Collected data were first summarized in 284 meaning units and then reduced to 53 common meanings through description, analysis, and interpretation processes that produced 16 sub-themes. Finally, six successful themes were extracted. The study results are as follows. First, the experience structure for successful entrepreneurs is formed by the qualitative difference of experience according to time order. Second, there are six successful themes found in the fashion start-up process. 1. Developing talent as entrepreneurs with a sense of fashion and enthusiasm 2. Passing on trial and error as a chance to communicate with customers 3. Challenge the fashion retail market with global online start-up opportunities 4. Building a system that responds to market environment changes 5. Leading and distinguishing with expertise from entrepreneurs 6. Evolve into the coexistence of members.