• Title, Summary, Keyword: Single-phase

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A Study on the Comparision of Performance between Three-phase Full-wave and Single-phase Full-wave X-ray Generators (삼상(三相)12펄스 전파정류장치(全波整流裝置)와 단상(單相) 전파정류장치(全波整流裝置)의 성능(性能) 비교(比較))

  • Kim, Young-Ill;Kim, Chang-Kyun;Huh, Joon
    • Journal of radiological science and technology
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    • v.3 no.1
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    • pp.81-86
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    • 1980
  • To compare three-phase 12-pulse full-wave X-ray generators with single-phase full-wave X-ray generators on their performance of outputs, authors studied the generating X-ray by means of exposure dose and radiographic density. The results were as follows; 1. The exposure doses of three-phase full-wave X-ray generators showed a 30%-60% increase as compared against of single-phase full-wave generators. 2. The transmitted doses of three-phase full-wave generators were more increased than single-phase full-wave X-ray generators. 3. To obtain the same density, 60kVp in three-phase full-wave generators were equivalent to $60{\sim}65kVp$ in single-phase full-wave generators, and 100kVp in those generators were equivalent to $100{\sim}125kVp$ in these generators.

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Comparison of Fault Current Limiting Characteristics between the separated Three-phase Flux-lock Type SFCL and the Integrated Three-phase Flux-lock Type SFCL (분리된 삼상 자속구속형 전류제한기와 일체화된 삼상 자속구속형 전류제한기의 전류제한 특성 비교)

  • Doo, Seung-Gyu;Du, Ho-Ik;Kim, Min-Ju;Park, Chung-Ryul;Kim, Yong-Jin;Lee, Dong-Hyeok;Han, Byoung-Sung
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.22 no.8
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    • pp.689-693
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    • 2009
  • We investigate the comparison of fault current characteristics between the separates three-phase flux-lock type superconducting fault current limiter(SFCL) and integrated three-phase flux-lock type superconducting fault current limiter(SFCL). The single-phase flux-lock type SFCL consists of two coils. The primary coil is wound in parallel to the secondary coil on an iron core and superconducting elements are connected to secondary coil in series. Superconducting elements are used by the YBCO coated conductor. The separated three-phase flux-lock type SFCL consists of single-phase flux-phase type SFCL in each phase. But the integrated three-phase flux-lock type SFCL consists of three-phase flux-reactors wound on an iron core. Flux-reactor consists of the same turn's ratio between coil 1 and coil 2 for each single phase. To compare the current limiting characteristics of the separated three-phase flux-lock type SFCL and integrated three-phase flux-lock type SFCL, the short circuit experiments are carried out fault condition such as the single line-to-ground fault. The experimental result shows that fault current limiting characteristic of the separated three-phase flux-lock type SFCL was better than integrated three-phase flux-lock type SFCL. And the integrated three-phase flux-lock type SFCL has an effect on sound phase.

A Study on the Harmonic Reduction Technique in Three-Phase Square-Wave Inverters Formed by Single-Phase Inverters (단상 인버터로 구성된 3상 구형파 인버터의 고조파 저감기법에 관한 연구)

  • 조승연
    • Proceedings of the KIPE Conference
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    • pp.355-359
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    • 2000
  • This paper deal with the harmonic reduction technique in three-phase square-wave inverter system formed by single-phase inverter. To reduce the harmonics six single-phase inverters are used for forming multi-phase inverter and zig-zag connected output transformer for eliminating the harmonic 6(2k-1)$\pm$1 orders. And an ac filter is furnished at output side. Computer simulations show that the THD of the output voltage can be reduced immensely.

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The speed control of the Single-Phase induction motor using P-I controller (비례 - 적분 제어기를 이용한 단상 유도 전동기의 속도 제어)

  • Sang, Doo-Whan;Cheong, Dal-Ho;Kim, Jung-Chul;Oh, Min-Jin
    • Proceedings of the KIEE Conference
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    • pp.603-605
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    • 1994
  • The Single-Phase induction motor is widely used in home appliances, especially refrigerator, air conditioner and washing machine. Recently many home appliances that use the motor require the speed control to get the various and convenient functions for the customers. Generally it is so hard to control the speed of the Single-Phase induction motor and to get the wide range of the speed variation. In this raper, the speed controller using P-I is designed for the Single-Phase induct ion Motor. The experimental results of the phase controller using P-I show the wide speed control of the Single-Phase induction motor and rebuff control to load change.

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Performances of Current-Waveform Modulated Single-Phase Induction Machine (전류파형을 변조한 단상유도전동기구의 특성에 관한 연구)

  • 황영문;김철우;박용규
    • 전기의세계
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    • v.24 no.1
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    • pp.55-62
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    • 1975
  • A single-phase induction motor with it's stator winding splitted into two series windings, of which the terminals of one winding is switched pulsationally by a thyristor type ON-OFF device so that the motor may operate as a pulsational shaded-pole motor, can modulate current waveforms of it's two series windings. In view of current waveform modulation method, a single-phase single-winding motor operates as a two-phase induction motor with asymmetrical axis windings where the starting torque can be obtained effectively without an auxiliary capacitor attached and it's running speed controlled by shifting phase between current waveforms differently. Equivalent circuit for analysis is modified from a double revolving field equivalent circuit of a single-phase induction motor with asymmetrical windings whose angle is 45.deg.C elet. degrees. Analysis and test results show that ON-OFF action of the pulsational shaded-pole winding has the same effect of a series capacitor, and then at heavy loads this motor operates with a small amonut of the input current than that having the fixed shaded-pole winding.

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Driving Characteristics of Single Phase SRM with Exciting Section (단상 SRM의 여자 구간에 따른 구동 특성)

  • Yeo, Sang-Kyom;Lee, Eun-Woong;Lee, Min-Myung
    • Proceedings of the KIEE Conference
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    • pp.912-914
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    • 2002
  • Single phase SRM(Switched Reluctance Motor) can not be started by itself and torque ripple is more generated than multi-phase SRM. But it is excited by single phase current and has very simple structure. Therefore it can be used in domestic appliance. Torque and speed of single phase SRM is controlled by adjusting exciting current and exciting section. Driver, which is composed with absolute encoder and DSP, is fabricated for control of exciting section on this paper. Then driving characteristics with exciting section is confirmed by using salient pole rotor type single phase SRM, which is fabricated in preceding research.

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Controller Design of Utility-connected Single-phase Inverter using d-q Theory (d-q이론을 이용한 개통 연계형 단상 인버터 제어기 설계기법)

  • Park, Chang-Joo;Kim, Chang-Hyun;Kim, Myung-Chul;Choi, Jae-Young
    • Proceedings of the KIEE Conference
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    • pp.1247-1249
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    • 2003
  • Despite many advantages, d-q theory was available only for three phase system. But recently, some papers proposed the application methods of d-a theory or similar theories for single phase systems. This paper presents the control method of the utility-connected single-phase inverter using d-q theory. The suggested method gives single-phase system instantaneous controllability and also makes the realization of APF(Active Power Filter) without DFT operation and PFC(Power Factor Controller) possible. This paper deals with utility-connected single phase inverter with PFC function. The controller was verified by simulation tool.

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Compensating Characteristics of Voltage Sag Compensator Utilizing Single-Phase Matrix Converter

  • Yamamoto, Kichiro;Ikeda, Keisuke;Iimori, Kenichi
    • Journal of international Conference on Electrical Machines and Systems
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    • v.2 no.1
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    • pp.77-82
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    • 2013
  • By using simulation, compensating characteristics of a voltage sag compensator utilizing single-phase matrix converter is examined. System configuration is described and mathematical model of single-phase matrix converter is derived by using the state space averaging method. In addition, the single-phase matrix converter is stabilized by phase-lead compensation. Finally, compensating characteristics of the compensator is investigated for 500 W R-L load and it is demonstrated that the compensator can operate correctly for loads for the range of power factor 0.6 (lagging) - 0.8 (leading) and for up to 50% voltage sag.

The Auxiliary Winding Control Characteristics of Single-Phase Induction Motor by Universal Starting Switch (범용 기동기에 의한 단상유도전동기의 보조권선 제어 특성)

  • 임홍우;임병옥;정수복;조금배;백형래
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.53 no.6
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    • pp.396-401
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    • 2004
  • Single phase induction motor(SPIM) is one of the most widely used type of low power AC motors in the world, especially for domestic or commercial applications where a three phase power supply is not available. Single phase induction motors have no starting torque their own. So there are several ways of starting single phase induction motors. The most common type is the starting capacitor installed in series with the auxiliary winding to increase the starting torque. In the conventional systems, this function is conducted by a centrifugal switch. But the mechanical centrifugal switch has many problems such as switch malfunction. This paper presents the auxiliary winding control using digital universal starting switch to overcome these shortcomings of centrifugal switch.

Comparison of Dynamic Characteristics of the Single phase induction motor at Single Phase and Two Phase control (단상 유도전동기의 단상 및 2상 제어 운전시 동작특성 비교)

  • Yang, B.Y.;Kwon, S.H.;Kwon, B.I.;Lee, C.G.
    • Proceedings of the KIEE Conference
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    • pp.936-938
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    • 2003
  • The single Phase induction motor is used to small size electronic appliance by production cost of a low-cost. But, it is low efficiency large torque ripple and impossible speed control. However we can change the speed if it similar to the three phase induction motor. And we studied about the two phase induction motor that torque ripple is smaller. So, in this paper the dynamic characteristics of the two phase induction motor are described and compared with the cage-type single phase induction motor to find the characteristics of the torque ripple and current, speed through the time-stepped finite element method.

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