• Title/Summary/Keyword: Tuned filter

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Single-Tuned Active Filter with Function of Double-Tuned Active Filter (Double Tuned Active Filter 기능을 갖는 Single Tuned Active Filter)

  • Kim Chan-Ki;Yang Byeong-Mo;Jung Gil-Jo
    • The Transactions of the Korean Institute of Power Electronics
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    • v.9 no.6
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    • pp.544-552
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    • 2004
  • This paper deals with the hybrid active filter which can reduce the 11th/13th harmonics in AC network by using the single tuned filter. Since the proposed algorithm uses the detuning compensation capability of the filter, the output voltage of the proposed active power filter is changed according to the capacitance of capacitors, magnitude of harmonic current, resonance frequency and control mode. In this paper, the control characteristics and the design of hybrid active filter is investigated. A new hybrid active filter with new algorithm, which is an active filter with single tuned filter instead of double tuned filter, is proposed.

An ANN Controlled Three-Phase Auto-Tuned Passive Filter for Harmonic and Reactive Power Compensation

  • Sindhu, M.R.;Nair, Manjula;Nambiar, T.N.P.
    • Journal of Power Electronics
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    • v.9 no.3
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    • pp.403-409
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    • 2009
  • Automatically tuned passive filters can improve power quality to a great extent in power systems. A novel three-phase shunt auto-tuned filter is designed to effectively compensate source current harmonics and to provide reactive power required by the non-linear load, which draws a highly reactive, harmonic-rich current from the supply. An artificial neural network (ANN) based controller selects filter component values in accordance with reactive power requirement and harmonic compensation. Traditional passive filters are permanently connected to the system and draw large amounts of source current even under light load conditions. By using auto-tuned filters, the passive filter components can be controlled according to load variations and, hence, draw only required source currents. The selection is done by the ANN with the help of a properly tuned knowledge base to provide instantaneous compensation using a digital controller.

A Study on Tuning Factor(δ) and Quality Factor(Q) Values in Design of Single-Tuned Passive Harmonic Filters (단일동조 수동고조파필터 설계시의 동조계수(δ) 및 양호도(Q)값 연구)

  • Cho, Young-Sik;Cha, Han-Ju
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.59 no.1
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    • pp.64-70
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    • 2010
  • This paper presents how to decide on tuning factor(${\delta}$) and quality factor(Q) values in design of single-tuned passive harmonic filters. Tuning factor(${\delta}$) and quality factor(Q) values have to consider before decision on circuit parameters of passive filters. A Study on these two value has not been scarcely performed and only experienced values has been used in passive harmonic filter design by far. As a experienced value, in cases of 5th and 7th filter, tuning factor(${\delta}$) is about 0.94 and 0.96 respectively and quality factor(Q) is, in all cases of, 50. If Single-tuned passive harmonic filter will be off-tuned, performance of filter will be decreased steeply and occur to parallel resonance between system reactance and filter capacitance. Therefore During the operation, In order not to off-tuning, Filter must be tuned at former order than actual tuning order. This is the same that total impedance of filter must have a reactive impedance. In this paper, Tuning factor(${\delta}$) is decided via example of real system and using the bode-plot and then performance of filters confirmed by filter current absorbtion rate. And Quality factor(Q) decided using the bode plot in example system and then performance of filters confirmed by filter current absorbtion rate also, which makes a calculated filter parameters to satisfy IEEE-519 distortion limits. Finally, Performance of the designed passive harmonic filter using the tuning factor(${\delta}$) and quality factor(Q) values, decided in this paper is verified by experiment and shows that 5th, 7th, 9th, 11th and 13th current harmonic distortions are decreased within IEEE-519 distortion limits, respectively.

A Study on the Design of Triple-tuned Filter for Line Commutated Converter HVDC (HVDC시스템 적용을 위한 Triple-tuned 필터 설계방법 연구)

  • Lee, Seong-Doo;Choi, Soon-Ho;Kim, Chan-Ki;Cha, HanJu
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.64 no.9
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    • pp.1288-1296
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    • 2015
  • The ac side current of a line commutated converter(LCC) high voltage direct current (HVDC) is characterized by highly non-sinusoidal waveform. If the harmonic current is allowed to flow in the connected ac network, it may cause unacceptable levels of distortion. Therefore, ac side filters are required as part of the total HVDC converter station, in order to reduce the harmonic distortion of the ac side current and voltage to acceptably low levels. The ac filters are also employed to compensate the requested reactive power because LCC HVDC also consume substantial reactive power. Among different types of filters, triple-tuned filters have been widely utilized for HVDC system. This paper presents two design methods of triple-tuned filter; equivalent method and parametric method. Using a parametric method, in particular this paper proposes a design algorithm for a triple tuned filter. Finally, the performance of the design algorithm is evaluated for a 250kV HVDC system in Jeju island. The results cleary demonstrate the effectiveness of proposed design method in harmonics reduction.

Harmonic Analysis of Reactor and Capacitor in Single-tuned Harmonic Filter Application

  • Kim, Jong-Gyeum;Park, Young-Jeen;Lee, Dong-Ju
    • Journal of Electrical Engineering and Technology
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    • v.6 no.2
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    • pp.239-244
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    • 2011
  • Industrial power distribution system includes many kinds of non-linear loads, which produce the harmonics during energy conversion transition. The single-tuned passive filter is widely used to absorb the harmonics and attenuate its undesirable effect in the distribution system. However, the passive filter might be severely stressed, and sometimes even damaged, due to the absorption of harmonics. There is voltage rise on the capacitor when the single-turned harmonic filter is applied. When the capacitor voltage rose above the allowable limit, the expected life of the capacitor will considerably deteriorate. On the other hand, the reactor can experience the spike voltage even if the voltage and current of the capacitor are within the allowable limit, and this accumulated voltage stress of the reactor causes its premature fault. In this paper, we analyzed and compared the harmonic voltage and current of the reactor and capacitor in a single-tuned harmonic filter through the EMTP software and verified them with the experimental results.

An Improved Multi-Tuned Filter for High Power Photovoltaic Grid-Connected Converters Based on Digital Control

  • Sun, Guangyu;Li, Yongli;Jin, Wei
    • Journal of Power Electronics
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    • v.18 no.1
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    • pp.160-170
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    • 2018
  • For high power photovoltaic (PV) grid-connected converters, high order filters such as multi-tuned filters and Traps+RC filters with outstanding filtering performance have been widely researched. In this paper, the optimization of a multi-tuned filter with a low damping resistance and research on its corresponding control scheme have been combined to improve the performance of the proposed filter. Based on the characteristics of the switching harmonics produced by PWM, the proposed filter is optimized to further improve its filtering performance. When compared with the more common Traps+RC filter, the advantages of the proposed filter with low damping resistances in attenuating the major switching harmonics have been demonstrated. In addition, a simpler topology and reduced power loss can be achieved. On the other hand, to make the implementation of the proposed filter possible, on the base of the unique frequency response characteristic of the proposed filter, a digital single-loop control scheme has been proposed. This scheme is a simple and effective means to suppress the resonance peak caused by a lack of damping. Therefore, a smaller volume, better efficiency of the proposed filter, and easy implementation of the corresponding control scheme can be realized. Finally, the superiority of the proposed filter topology and control scheme is verified in experiments.

A Study on Frequency Controlled Bandwidth adjustable Bandpass Filter (주파수제어 대역폭조정 대역통과 여파기에 관한 연구)

  • 최갑석
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.12 no.1
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    • pp.18-26
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    • 1975
  • In this paper, a frequency controlled bandwidth adjustable bandpass filter consisting of 4-path system is precented. It is shown that this system has characteristics similar to ihose of the magneticuly coupled double tuned amplifier and the center frequency of the passband is able to be shifted contineolisly. The adjustable range of the bartdwidth of the filter system is anslyzed for she case of the double and single tuned characteristics. The experiment has been conducted to verify the theory of this system and the experimental resulis are in good agreement with the theoretically calculated values.

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Double-tuned Filter Design For HVDC System (HVDC System 적용 Double-tuned 필터의 설계 방법 연구)

  • Lee, Hee-Jin;Nam, Tae-Sik;Son, Gum-Tae;Park, Jung-Wook;Chung, Yong-Ho;Lee, Uk-Hwa;Baek, Seung-Taek;Hur, Kyeon
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.9
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    • pp.1232-1241
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    • 2012
  • The ac side current of an high voltage direct current (HVDC) converter is characterized by highly non-sinusoidal waveform. If the harmonic current is allowed to flow in the connected ac system, it may cause unacceptable levels of distortion. Therefore, ac side filters are required as part of the total HVDC converter station, in order to reduce the harmonic distortion of the ac side current and voltage to acceptably low levels. The ac side filters are also employed to compensate network requested reactive power because HVDC converters also consume substantial reactive power. Among different types of filters, double-tuned filters have been widely utilized for HVDC system. This paper presents two design methods of double-tuned filter; equivalent method and parametric method. Using a parametric method, in particular the paper proposes a new design algorithm for a realistic system. Finally, the performance of the design algorithm is evaluated for a 80kV HVDC system in Jeju island with PSCAD/EMTDC program. The results cleary demonstrate the effectiveness of proposed design method in harmonics elimination and steady-state stability.

A Hybrid Active Power Filter for Electric-Railway Systems Using Multi-Level Inverters (멀티레벨 인버터를 이용한 전기철도용 하이브리드 능동 전력필터)

  • 김윤호;김수홍;이강희
    • Journal of the Korean Society for Railway
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    • v.7 no.4
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    • pp.339-344
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    • 2004
  • This paper proposes transformerless power conversion system consisting of a single-phase diode rectifier and a shunt hybrid filter for the electric-railway system. The hybrid filter consists of a single tuned LC filter per a phase and a low-rated NPC type multi-level inverter. Compared with conventional active filters. transformers are not used. Also, LC filter works as not only a harmonic filter tuned at the 3rd harmonic frequency but also a switching-ripple filter. The rating of the active filter can be decreased by using a NPC type multi-level inverter. The simulation results confirm the validity of the system.

A Hybrid Active Power Filter for Electric-Railway Systems using Multi-Level Inverters (멀티레벨 인버터를 이용한 전기철도용 하이브리드 능동전력필터)

  • Kim Yoon-Ho;Kim Soo-Hong;Rho Sung-Chan;Lee Kang-Hee
    • Proceedings of the KSR Conference
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    • 2004.06a
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    • pp.1334-1339
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    • 2004
  • This paper proposes transformerless power conversion system consisting of a single-phase diode rectifier and a shunt hybrid filter for the electric-railway system. The hybrid filter consists of a single tuned LC filter per a phase and a low-rated NPC type multi-level inverter. Compared with conventional active filters. Transformers are not used. Also, LC filter works as not only a harmonic filter tuned at the 5th harmonic frequency but also a switching-ripple filter. The rating of the active filter can be decreased by using a NPC type multi-level inverter. The simulation results confirm the validity of the system.

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