• Title, Summary, Keyword: Saturation Factor

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Study on Analysis of Single Phase Induction Motor Considering Saturation Factor (포화계수를 고려한 단상 유도전동기의 해석에 관한 연구)

  • Cho, Su-Yeon;Kim, Kwang-Soo;Im, Jong-Bin;Ryu, Gwang-Hyeon;Oh, Se-Young;Ahn, Han-Woong;Lee, Ju
    • Proceedings of the KIEE Conference
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    • pp.846-847
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    • 2011
  • This paper presents the study on analysis of single phase induction motor characteristics by equivalent circuit. For high efficiency of single phase induction motor, the motor parameters used for equivalent circuit analysis is important. The accuracy of equivalent circuit analysis of motor depends on the circuit parameters like saturation factor. Therefore this paper proposed the analysis method considering saturation factor. The saturation factor was calculated by iteration routine and numerical method. this proposed method was verified by FEM analysis results and dynamo test results of the prototype model.

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Characteristics Analysis of Single Phase Induction Motor via Equivalent Circuit Method and Considering Saturation Factor

  • Cho, Su-Yeon;Kim, Won-Ho;Jin, Chang-Sung;Kang, Dong-Woo;Lee, Ju
    • Journal of Electrical Engineering and Technology
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    • v.9 no.1
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    • pp.178-183
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    • 2014
  • This paper presents a motor characteristics analysis method using an equivalent circuit. Motor characteristics analysis via equivalent circuit is very important for designing a high efficiency single phase induction motor. The accuracy of the motor characteristics depends on the accuracy of the parameters, especially saturation factor, which determines the cyclical relationship in the analysis process. Therefore, using the proposed method, the saturation factor was calculated using the iteration routine and numerical technique. The proposed method was verified by comparing the finite element method results and the dynamo test results of manufactured prototype model.

Theoretical Analysis of the Electrical Saturation Behavior of the DH Laser Diode (DH Laser Diode의 전기적 포화현상에 관한 이론적 해석)

  • 박영규;권영기
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.15 no.5
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    • pp.34-38
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    • 1978
  • In this Paper, the saturation behavior in the electrical phenomena of the DH Laser diode is explained theoretically using rate equnations. The carrier density approaches to ns gradually well above the threshold and theoretically expected curve of and calculated value of $\Delta$Vj are exactly equal to the experimental results which was observed, as shown. The carrier saturation factor If is proposed and we show k$\beta$ is a measure of the ideality of the sample diode. In the light of relation, the sample diode's idoality increases as f decreases.

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A Design Method of Iron-cored CTs To Prevent Satruation (포화를 방지하기 위한 보호용 철심 변류기 설계 방법)

  • Lee, Ju-Hun;Gang, Sang-Hui;Gang, Yong-Cheol;Lee, Seung-Jae;Bae, Ju-Cheon;An, Jun-Gi;Lee, Cheong-Hak;Lee, Jeong-Taek
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.2
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    • pp.119-126
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    • 1999
  • Current transformer (CT) saturation may cause a variety of protective relays to malfunction. The conventional CT is designed that it can carry up to 20 times the rated current without exceeding 10% ratio error. However, the possibility of CT saturation still remains if the fault current contains substantial amounts of ac and/or dc components. This paper presents a design method of iron-cored CTs for use with protective relays to prevent CT saturation. The proposed design method determines the core cross section of the CT; it employs the transient dimensioning factor to consider relay's operating time (duty cycle) and dc component as well as ac components contained in the fault current, and symmetrical short-circuit current factor to consider as well as ac components contained in the fault current, and symmetrical short-circuit current factor to consider the biggest fault current. The method designs the cross section of CTs in cases of reclosure and no reclosure.

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Color Saturation Improvement using the Maximum Color Difference Table (최대색차신호 표를 이용한 컬러 채도 향상)

  • Kim, Sun-Jung;Hong, Sung-Hoon
    • Journal of Korea Multimedia Society
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    • v.16 no.2
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    • pp.119-130
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    • 2013
  • In this paper, we propose a new color image enhancement method to improve the color saturation as well as luminance contrast in the YCbCr color space. The proposed method uses the maximum color difference table to compensate the perceived saturation changes due to luminance contrast changes. To improve the color saturation, the method first calculates the weighting factor by using the maximum color difference table and then multiplies the weighting factor to the input color difference signals. In this step, it maps color difference signals to proper color region to prevent the color distortion by considering the correlation of color saturations depending on the luminance and hue. The experimental results show that our method effectively improves color saturation compared to the conventional methods.

Loss Minimization Control of Interior Permanent Magnet Synchronous Motors Considering Self-Saturation and Cross-Saturation

  • Pairo, Hamidreza;Khanzade, Mohammad;Shoulaie, Abbas
    • Journal of Power Electronics
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    • v.18 no.4
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    • pp.1099-1110
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    • 2018
  • In this paper, a loss minimization control method for interior permanent magnet synchronous motors is presented with considering self-saturation and cross saturation. According to variation of the d-axis and q-axis inductances by different values of the d-axis and q-axis components of currents, it is necessary to consider self-saturation and cross saturation in the loss minimization control method. In addition, the iron loss resistance variation due to frequency variation is considered in the condition of loss minimization. Furthermore, the loss minimization control method is compared with maximum torque per ampere (MTPA), unity power factor (UPF) and $i_d=0$ control methods. Experimental results verify the performance and proper dynamic response of the loss minimization control method with considering self-saturation and cross saturation.

Compensation of Periodic Magnetic Saturation Effects for the High-Speed Sensorless Control of PMSM Driven by Inverter Output Power Control-based PFC Strategy

  • Lee, Kwang-Woon
    • Journal of Power Electronics
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    • v.15 no.5
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    • pp.1264-1273
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    • 2015
  • An inverter output power control based power factor correction (PFC) strategy is being extensively used for permanent magnet synchronous motor (PMSM) drives in appliances because such a strategy can considerably reduce the cost and size of the inverter. In this strategy, PFC circuits are removed and large electrolytic DC-link capacitors are replaced with small film capacitors. In this application, the PMSM d-q axes currents are controlled to produce ripples, the frequency of which is twice that of the AC main voltage, to obtain a high power factor at the AC mains. This process indicates that the PMSM operates under periodic magnetic saturation conditions. This paper proposes a back electromotive-force (back-EMF) estimator for the high-speed sensorless control of PMSM operating under periodic magnetic saturation conditions. The transfer function of the back-EMF estimator is analyzed to examine the effect of the periodic magnetic saturation on the accuracy of the estimated rotor position. A simple compensation method for the estimated position errors caused by the periodic magnetic saturation is also proposed in this paper. The effectiveness of the proposed method is experimentally verified with the use of a PMSM drive for a vacuum cleaner centrifugal fan, wherein the maximum operating speed reaches 30,000 rpm.

Discussion on Dilution Factor for Electrical Conductivity Measured by Saturation-paste Extract and 1:5 Soil to Water Extract, and CEC of Korean Soils (한국 토양에 대한 포화침출액법과 1:5 법에 의한 전기전도도 간의 희석배수와 CEC의 관계에 대한 고찰)

  • Jung, Yeong-Sang;Joo, Jin-Ho;Hong, Sun-Dal;Lee, In-Bog;Ro, Hee-Myong
    • Korean Journal of Soil Science and Fertilizer
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    • v.34 no.1
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    • pp.71-75
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    • 2001
  • Linear regression analyses between the electrical conductivity of the saturation-paste extract. ECe, and the electrical conductivity of the 1:5 soil extract, EC1:5, for different soils yielded different dilution factors, or slopes with significant $r^2$ values from 0.842 to 0.905. The dilution factor was inversely proportional to the cation exchange capacity of soil which reflected textural difference. The dilution factors recommended for different textural classes ranged from 6.44 for clay soil to 12.29 for sandy soil based on the CEC's of the textural classes among 350 surface soils recorded in the Taxonomical Classification of Korean Soils except volcanic ash derived soils. Though saturation percentage of the saturation-paste of the soils in this study, CEC should be taken into account for dilution factor between ECe and EC1:5, and the suggested dilution factors might be reasonable estimate for the soil textural classes.

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Geomorphologic Nash Model with Variable Width Function

  • Thuy, Nguyen Thi Phuong;Kim, Joo-Cheol;Jung, Kwansue
    • Proceedings of the Korea Water Resources Association Conference
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    • pp.212-212
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    • 2015
  • So far, geomorphologic dispersion due to the heterogeneity characteristics of flow paths in a basin has been demonstrated as a major factor affecting to the hydrologic response function of a catchment. This effect has considered by many previous studies taking into account flow path length factors, especially in the application of width function. Based upon the analysis of topographic index, another important geomorphologic factor extracted from DEM data, this work presents a new factor named saturation to evaluate its effects to the formation of the well-known instantaneous unit hydrograph (IUH) in Nash model and drainage structure in a river basin. First, the geomorphologic parameters corresponding to different saturation conditions are computed from DEM data with the support of GIS software. Then, in the combination of hydrologic and geomorphologic data, effective rainfall in each saturation degree and the Nash parameters are calculated using excel. Finally, the verification process with direct runoff data is conducted using Fortran programming. This process is applied to five sub-watersheds in Bocheong catchment ($485.21km^2$) in Korea where the necessary data are available and believable. The results from this approach will improve researchers and students'understandings about the relationship between rainfall and runoff and its relation with drainage structure within a catchment.

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A Study on the Development of Sleep Monitoring Smart Wear based on Fiber Sensor for the Management of Sleep Apnea (수면 무호흡증 관리를 위한 섬유센서 기반의 슬립 모니터링 스마트 웨어 개발에 관한 연구)

  • Park, Jin-Hee;Kim, Joo-Yong
    • Science of Emotion and Sensibility
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    • v.22 no.1
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    • pp.89-100
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    • 2019
  • Sleep apnea, a medical condition associated with a variety of complications, is generally monitored by standard sleep polysomnography, which is expensive and uncomfortable. To overcome these limitations, this study proposes an unconstrained wearable monitoring system with stretch-fiber sensors that integrate with the wearer's clothing. The system allows patients to undergo examinations in a familiar environment while minimizing the occurrence of skin allergies caused by adhesive tools. As smart clothing for adult males with sleep apnea, long-sleeved T-shirts embedding fibrous sensors were developed, enabling real-time monitoring of the patients' breathing rate, oxygen saturation, and airflow as sleep apnea diagnostic indicators. The gauge factor was measured as 20.3 in sample 4. The maximum breathing intake, measured during three large breaths, was 2048 ml. the oxygen saturation was measured before and during breath-holding. The oxygen saturation change was 69.45%, showing a minimum measurable oxygen saturation of 70%. After washing the garment, the gauge factor reduced only to 18.0, confirming the durability of the proposed system. The wearable sleep apnea monitoring smart clothes are readily available in the home and can measure three indicators of sleep apnea: respiration rate, breathing flow and oxygen saturation.