• Title/Summary/Keyword: Sinusoidal input

Search Result 388, Processing Time 0.022 seconds

A Study on the Cycloconverter with a LC Resonant Circuit (LC 공진 회로를 이용한 사이크로콘버터에 관한 연구)

  • Kim, Young-Suk;Cho, Kyu-Min;Park, Sung-Jin
    • Proceedings of the KIEE Conference
    • /
    • 1990.07a
    • /
    • pp.376-379
    • /
    • 1990
  • This parer presents a cycloconverter with a LC resonant circuit for a induction motor drive. The cycloconverter can provide variable voltage and frequency three phase output while keeping the input displacement factor at 1.0. The input current wave for is are sinusoidal,and the wide output frequency range is appropriate for variable speed AC motor drives.

  • PDF

10KVA Series-Parallel compensated UPS (10KVA 급 직병렬 보상형 무정전 전원 장치)

  • Jeon, Seong-Jeub;Cho, Gyu-Hyeong
    • Proceedings of the KIEE Conference
    • /
    • 2000.07b
    • /
    • pp.1083-1086
    • /
    • 2000
  • In this paper a development of 10KVA series-parallel compensated UPS is shown, which has high input power factor and sinusoidal output voltage regulation capability. Compared to conventional cascaded UPS, the size can be reduced significantly with high quality input and output waveforms. The front converter and the main inverter can be considered decoupled, hence the front converter and the main inverter can be designed independent of each other. In this paper, analysis and experimental results for an 10 KVA prototype are presented.

  • PDF

The Load Current Observer Design for Torque Control of DC Meter (직류 전동기의 속도 토크 제어를 위한 부하 전류 관측기 설계)

  • Seo Young-Soo;Kim Eun-Gi;Kim Yong-Ju
    • Proceedings of the KIPE Conference
    • /
    • 2001.07a
    • /
    • pp.155-158
    • /
    • 2001
  • In this paper, the Load Current Observer Design for 3-phase Voltage Type PWM Converter with DC Meter Load. The sinusoidal input current and unity input power factor are realised based on the estimated source voltage performed by the Load Current Observer using actual currents and DC link voltage.

  • PDF

Analysis of Input·Output Characteristics in the PWM Converter with Unbalance Supply Voltage (불평형 전원 전압을 갖는 PWM 컨버터의 입·출력 특성 분석)

  • Khoo, Ja-Kyeung;Kim, Sang-Hoon
    • Journal of Industrial Technology
    • /
    • v.25 no.B
    • /
    • pp.203-210
    • /
    • 2005
  • The PWM(Pulse Width Modulated) converter for the AC to DC rectification has become attractive in the industrial variable-speed drive application and the electric utilities due to the following benefits: Nearly the sinusoidal input current with unity power factor; Controllable DC link voltage; Bidirectional power flow. This paper presents a quantitative analysis of single and three phase PWM converter's input and output characteristics as a function of the input filter inductance under balanced and unbalanced conditions. Also, its performance under the supply voltage including harmonics is investigated by simulation with Matlab Simlulink and experiments. These results provide a reference for selecting the reasonable converter's input filter inductance for given harmonics or power factor criterion.

  • PDF

Voltage Sensorless Control for Three-Phase Voltage Source PWM Converter (3상 전압형 PWM 컨버터의 전압 센서리스 제어)

  • Heo, Tae-Won;Cho, Kwang-Seung;Kim, Young-Bin;Seo, Jung-Ki;Cho, Yong-Gil;Woo, Jung-In
    • Proceedings of the KIEE Conference
    • /
    • 1999.07f
    • /
    • pp.2656-2658
    • /
    • 1999
  • This paper presents a control scheme for a three-phase PWM converter system without any voltage sensors. Two input currents and one load current are measured. In a general PWM converter system, the required AC input and DC output voltage values in order to control the converter are estimated using the differential equations of the converter from the measured input currents and load current values in the switch modes of the converter circuit. The PI controller is used as DC voltage controller and sinusoidal tracking controller which tracks directly AC input current is used as input current controller. The Proposed method is verified by simulations. This paper describes the estimation method and configuration of the controller, and discusses steady state and transient performances of the converter

  • PDF

The Analysis of The Three Phase Rectifier (다중 3상 PWM 정류기의 해석)

  • Shin, D.H.;Youn, K.S.;Cho, J.G.;Kwon, W.H.
    • Proceedings of the KIEE Conference
    • /
    • 1995.11a
    • /
    • pp.242-245
    • /
    • 1995
  • In this paper the multiple three rectifiers for the power factor correction are proposed, analyzed and designed. The multiple three phase rectifiers draw sinusoidal ac currents from the ac voltage sources with nearly unity input power factor and operate with PWM making the control circuit simple and system cost low. Outstandingly it reduces the rated power capacity of devices and the input filter size by reducing input current ripples. Moreover design rules can be obtained from input and output current equations. With the proposed rules, input power factor and output power capacity are determined approximately. Finally these design rules are verified with computer simulations.

  • PDF

A Novel Switching Mode for High Power Factor Correction and Low THD

  • Park, Gyumin;Eum, Hyunchul;Yang, Seunguk;Hwang, Minha;Park, Inki
    • Proceedings of the KIPE Conference
    • /
    • 2018.07a
    • /
    • pp.210-212
    • /
    • 2018
  • A new switching mode has been proposed to obtain high power factor and low THD in single stage AC-DC converter. The conventional voltage mode control in critical conduction mode distorts input current shape with poor THD in flyback topology. Once TRIAC dimmer is connected, visible flicker in the LED lamp is easily detected due to a lack of TRAIC holding current near the input voltage zero cross. The newly proposed method can shape the input current by providing a desired reference voltage so that low THD is obtained by ideal sinusoidal input current in case of no dimmer connection and flat input current performs good TRIAC dimmer compatibility in phase-cut dimming condition. To confirm the validity of the proposed method, theoretical analysis and experimental result from 8W dimmable LED lighting system are presented.

  • PDF

Reduction of Input Current Harmonics for Three Phase PWM Converter Systems under a Distorted Utility Voltage

  • Park, Nae-Chun;Mok, Hyung-Soo;Kim, Sang-Hoon
    • Journal of Power Electronics
    • /
    • v.10 no.4
    • /
    • pp.428-433
    • /
    • 2010
  • This paper proposes a harmonics reduction technique for the input currents of three phase PWM converters. The quality of the phase angle information on the utility voltage connected to the PWM converters affects their control performance. Under a distorted utility voltage, the extracted phase angle based on the synchronous reference frame PLL method is distorted. This causes large harmonics in the input currents of a PWM converter. In this paper, a harmonics reduction method that makes the input currents in the PWM converter sinusoidal even under distorted utility conditions is proposed. By the proposed method, without additional hardware, the THD (Total Harmonic Distortion) of the input currents can be readily limited to below 5% which is the harmonic current requirements of IEEE std. 519. Its validity is verified by simulations and experimental results.

Analysis of input current in a Boost AC-DC converter using the partial resonant method (부분공진 승압형 AC-DC 컨버터의 입력전류 해석)

  • Kwak, Dong-Kurl;Lee, Kyung-Chin;Park, Jum-Mun;Lee, Jin-Ho;Kim, Young-Mun;Lee, Hyun-Woo
    • Proceedings of the KIEE Conference
    • /
    • 1995.07a
    • /
    • pp.185-187
    • /
    • 1995
  • A boost converter proposed in this paper operates with high power factor due to input current of sinusoidal waveform. If there were no input LPF, the current is got to be discontinuos form in proportion to AC input voltage magnitude under the constant duty factor switching. Thereupon, the harmonics of input current waveform is reduced and the LPF is made with few elaboration and the control circuit is simple. The switching devices in proposed circuit are operated with soft switching by the partial resonant method. The patial resonant circuit makes use of a reactor using step-up and a capacitor of loss-less snubber. The result is that switching loss is very low and efficiency of system is high.

  • PDF

A Study on the Rejection of Dynamic Disturbance Forces in a Magnetically Suspended System Using Flux Feedback (자기력 부상 시스템에서 자속궤한을 이용한 동적 외란력의 제거에 관한 연구)

  • Kim, Jong-Ki;Lee, Key-Seo;Lee, Jun-Ho
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.16 no.3 s.108
    • /
    • pp.283-290
    • /
    • 2006
  • This study is concerned with static and sinusoidal disturbance rejection for a single periodic input disturbance with known period. In the area of active elimination of a disturbance force, the control input should have two different kinds of gains: one is to deliver a stable control and the other is a force component to cancel the external disturbance force. In this paper we employ a simple state feedback control law to make the balance beam stable and employ a linear observer to estimate the states which represent the external disturbance force components. Simulation results verify our proposed control method to reject a static and sinusoidal disturbance force.