JPH10145972A - Control method for power active filter - Google Patents
Control method for power active filterInfo
- Publication number
- JPH10145972A JPH10145972A JP8298270A JP29827096A JPH10145972A JP H10145972 A JPH10145972 A JP H10145972A JP 8298270 A JP8298270 A JP 8298270A JP 29827096 A JP29827096 A JP 29827096A JP H10145972 A JPH10145972 A JP H10145972A
- Authority
- JP
- Japan
- Prior art keywords
- harmonic
- amplitude
- load current
- component
- data
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/20—Active power filtering [APF]
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、電力系統に生ずる
高調波を吸収する電力用アクティブフィルタの制御方式
に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control system for an active power filter for absorbing harmonics generated in a power system.
【０００２】[0002]
【従来の技術】電力用アクティブフィルタ（ＡＦ）は負
荷電流の高調波成分を検出してこれを電流指令として高
調波成分を打ち消すようにインバータの出力電流を制御
する。2. Description of the Related Art An active power filter (AF) detects a harmonic component of a load current, and controls the output current of an inverter so as to cancel the harmonic component by using this as a current command.
【０００３】ＡＦの制御には図３に示すようなｐ−ｑ演
算法が多く用いられている。これは電流検出器ＣＴLで
検出した３相の負荷電流ＩLを電源電圧位相で座標変換
する３相２相変換回路３１でｐ−ｑ軸電流Ｉｐ，Ｉｑに
変換し、ハイパスフィルタ３３，３４でその交流分を検
出し、２相３相変換回路３５で３相に変換して３相の高
調波分電流を得、これを電流指令値Ｉｈ＊としてインバ
ータ２を制御している。For controlling the AF, a pq calculation method as shown in FIG. 3 is often used. It converts the three-phase two-phase conversion circuit 31 for coordinate transformation of the load current I L of the three-phase detected by the current detector CT L by the power supply voltage phase p-q axis current Ip, the Iq, a high-pass filter 33 The two-phase / three-phase conversion circuit 35 converts the current into three phases to obtain a three-phase harmonic current, which is used as a current command value Ih * to control the inverter 2.
【０００４】このｐ−ｑ演算法の他に図４に示すような
バンドパスフィルタ方式がある。これは電流検出器ＣＴ
Lで検出した負荷電流ＩLを２次〜ｎ次高調波をそれぞれ
通す２次〜ｎ次バンドパスフィルタ４１2〜４１nを用い
てそれぞれ２次〜ｎ次高調波成分を検出し、加算器４２
で加算して高調波分電流とし、これを電流指令値Ｉｈ＊
としてインバータ２を制御するものである。In addition to the pq operation method, there is a band pass filter method as shown in FIG. This is the current detector CT
The second to n-th order harmonic components are respectively detected by using the second to n-th order band-pass filters 41 2 to 41 n which pass the second to n-th order harmonics of the load current I L detected by L , respectively. 42
To obtain a harmonic component current, which is referred to as a current command value Ih *.
To control the inverter 2.
【０００５】[0005]
【発明が解決しようとする課題】ところで、上記図３の
ｐ−ｑ演算法は、高調波成分を一括し検出して制御する
ため各次数に分けて細かく制御することができない。ま
た、図４のバンドパスフィルタ方式は各次高調波成分を
それぞれ各バンドパスフィルタにより検出しているの
で、各次数に分離することは可能であるが、補償しよう
とする次数分のハイパスフィルタ回路が必要となり、ま
た分離した特性がフィルタの回路定数によって決まって
しまう欠点がある。In the pq operation method shown in FIG. 3, since harmonic components are detected and controlled collectively, fine control cannot be performed for each order. Further, in the band-pass filter system shown in FIG. 4, since each higher-order harmonic component is detected by each band-pass filter, it is possible to separate each higher-order component. However, a high-pass filter circuit for the order to be compensated can be used. And there is a disadvantage that the separated characteristics are determined by the circuit constant of the filter.
【０００６】本発明は、従来のこのような問題点に鑑み
てなされたものであり、その目的とするところは、次数
分の回路を用いることなく、各次高調波の振幅及び位相
を細かく制御することができるアクティブフィルタの制
御方法を提供することにある。The present invention has been made in view of such conventional problems, and has as its object to finely control the amplitude and phase of each harmonic without using circuits of the order. An object of the present invention is to provide a control method of an active filter that can perform the control.
【０００７】[0007]
【課題を解決するための手段】本発明は、負荷電流信号
を高速フーリエ変換演算回路でフーリエ解析し、その解
析データからディジタルフィルタ演算回路で負荷電流高
調波の振幅，位相データを求め、このデータを基に各次
高調波合成回路で補償電流指令値を求める。前記ディジ
タルフィルタ演算回路からのデータは各次成分の振幅及
び位相情報が完全に分離されたものとなるので、合成す
る次数成分を選択することにより負荷電流高調波を次数
ごとに補償することが可能となる。According to the present invention, a load current signal is subjected to Fourier analysis by a fast Fourier transform operation circuit, and the amplitude and phase data of the load current harmonic are obtained from the analysis data by a digital filter operation circuit. , A compensation current command value is obtained in each of the higher harmonic synthesis circuits. Since the data from the digital filter operation circuit is obtained by completely separating the amplitude and phase information of each order component, it is possible to compensate the load current harmonic for each order by selecting the order component to be synthesized. Becomes
【０００８】[0008]
実施の形態１ 図１にアクティブフィルタの制御ブロックを示す。同図
において、１はアクティブフィルタ（ＡＦ）、２は系統
に出力するＡＦのインバータ、３は負荷電流検出器ＣＴ
Lで検出した負荷電流ＩLをフーリエ解析するＦＦＴ（高
速フーリエ変換）演算回路、５はフーリエ解析されたデ
ータから負荷電流の各次数成分の振幅及び位相データを
得るディジタルフィルタ演算回路、９はそのデータを合
成してインバータ２へ補償電流指令値Ｉｈ＊を出力する
各次高調波合成回路である。Embodiment 1 FIG. 1 shows a control block of an active filter. In the figure, 1 is an active filter (AF), 2 is an AF inverter that outputs to the system, and 3 is a load current detector CT.
FFT (Fast Fourier Transform) arithmetic circuit for performing Fourier analysis of load current I L detected by L , digital filter arithmetic circuit 5 for obtaining amplitude and phase data of each order component of load current from data subjected to Fourier analysis, 9 Each harmonic synthesis circuit synthesizes data and outputs a compensation current command value Ih * to the inverter 2.
【０００９】本発明は、負荷電流ＩLをＦＦＴ演算回路
３でフーリエ解析し、ディジタルフィルタ演算回路５で
フィルタ演算して負荷電流高調波の各次成分の振幅及び
位相データを求める。このため各次成分の振幅及び位相
情報は完全に分離できる。According to the present invention, the load current IL is subjected to Fourier analysis by the FFT operation circuit 3 and the digital filter operation circuit 5 performs filter operation to obtain the amplitude and phase data of each order component of the load current harmonic. Therefore, the amplitude and phase information of each next component can be completely separated.
【００１０】この分離された各次成分の振幅位相データ
を基に各次高調波合成回路９で補償しようとする各次成
分のデータを合成して補償電流指令値Ｉｈ＊得る。した
がって、ＡＦは負荷電流の高調波を次数毎にきめ細かに
抑制することが可能となる。Based on the separated amplitude and phase data of each of the next-order components, data of each of the next-order components to be compensated by each of the higher-order harmonic synthesis circuits 9 is synthesized to obtain a compensation current command value Ih *. Therefore, the AF can finely suppress the harmonics of the load current for each order.
【００１１】実施の形態２ 図２アクティブフィルタ（ＡＦ）の制御ブロックの他の
例を示す。なお、前記図１に示したものと同一構成部分
は、同一符号を付してその重複する説明を省略する。Embodiment 2 FIG. 2 shows another example of the control block of the active filter (AF). The same components as those shown in FIG. 1 are denoted by the same reference numerals, and the description thereof will not be repeated.
【００１２】図２において、４は電源電流検出器ＣＴS
で検出した電源電流ＩSをフーリエ解析するＦＦＴ演算
回路、６はそのフーリエ解析されたデータから負荷電流
の各次数成分の振幅及び位相データを得るディジタルフ
ィルタ演算回路、７はディジタルフィルタ演算回路４及
び６からの同時検出の負荷電流ＩL及び電源電流ＩSの高
調波の振幅及び位相データを比較して負荷高調波と電源
高調波の伝達特性を求める伝達特性演算回路。In FIG. 2, reference numeral 4 denotes a power supply current detector CT S
In FFT calculation circuit for Fourier analysis of the power current I S detected, 6 digital filter operation circuit for obtaining an amplitude and phase data of each order component of the load current from the Fourier analysis data, 7 digital filter operation circuit 4 and load current I L and the power supply current I S transfer characteristic calculation circuit harmonics by comparing the amplitude and phase data determine the transfer characteristic of the load harmonics and power harmonics of simultaneous detection of six.
【００１３】８はディジタルフィルタ演算回路５からの
負荷電流高調波の振幅及び位相データを上記負荷高調波
と電源高調波の伝達特性で調整する振幅・位相調整回
路、９はこの調整された負荷電流の各次高調波の振幅及
び位相データを合成してインバータ２へ補償電流指令値
Ｉｈ＊を出力する各次高調波合成回路である。Reference numeral 8 denotes an amplitude / phase adjusting circuit for adjusting the amplitude and phase data of the load current harmonic from the digital filter operation circuit 5 by using the transfer characteristics of the load harmonic and the power supply harmonic, and 9 denotes the adjusted load current. , And outputs the compensation current command value Ih * to the inverter 2 by synthesizing the amplitude and phase data of each harmonic.
【００１４】本発明は、負荷電流ＩL及び電源電流ＩSを
同時に検出し、それぞれ高速フーリエ変換回路３及び５
とディジタルフィルタ演算回路４及び６で電流ＩL，ＩS
の高調波を各次数成分に分離し、伝達特性演算回路７で
比較して負荷電流高調波と電源電流高調波の伝達特性を
求め、振幅・位相調整回路８でこの伝達特性に基づいて
フィルタ演算回路５からの分離された負荷電流高調波の
各次成分の振幅及び位相データを調整する。例えば、負
荷高調波電流と電源高調波電流の振幅比（振幅特性）よ
り、電源側の成分が負荷側の成分よりも大きい場合は、
その成分がアクティブフィルタの動作にも関わらず拡大
されていることになる。（系統共振現象）従って、振
幅，位相調整回路８においてその補償成分の振幅や位相
を上記振幅特性が最小になるように調整し、後段の各次
高調波合成回路９にてその他の正常な高調波成分（振幅
特性が拡大傾向にない成分）と合成して補償電流値Ｉｈ
＊を出力すれば高調波の拡大を防止することができる。
即ち、アクティブフィルタは、系統の特性に見合った最
適な補償特性を得ることが可能となる。（系統診断機
能）According to the present invention, the load current I L and the power supply current I S are simultaneously detected, and the fast Fourier transform circuits 3 and 5 are respectively detected.
And the digital filter operation circuits 4 and 6, the currents I L and I S
Are separated into respective order components, and the transfer characteristic calculation circuit 7 compares them to obtain the transfer characteristics of the load current harmonic and the power supply current harmonic. The amplitude / phase adjustment circuit 8 calculates the filter based on the transfer characteristics. The amplitude and phase data of each component of the load current harmonic separated from the circuit 5 is adjusted. For example, according to the amplitude ratio (amplitude characteristic) of the load harmonic current and the power supply harmonic current, when the component on the power supply side is larger than the component on the load side,
That component is expanded in spite of the operation of the active filter. (System resonance phenomenon) Therefore, the amplitude and phase of the compensating component are adjusted in the amplitude and phase adjusting circuit 8 so that the amplitude characteristic is minimized, and the other normal harmonics are synthesized in each subsequent harmonic synthesizing circuit 9 in the subsequent stage. Compensating current value Ih by combining with a wave component (a component whose amplitude characteristic does not tend to expand)
If * is output, the expansion of harmonics can be prevented.
That is, the active filter can obtain an optimum compensation characteristic corresponding to the characteristic of the system. (System diagnosis function)
【００１５】[0015]
【発明の効果】本発明は、上述のとおり構成されている
ので、次に記載する効果を奏する。Since the present invention is configured as described above, the following effects can be obtained.
【００１６】（１）補償しようとする各次高調波の振幅
及び位相を細かく制御することが可能となる。(1) The amplitude and phase of each higher harmonic to be compensated can be finely controlled.
【００１７】（２）負荷電流と電源電流の検出を同時に
行い系統の伝達特性の診断による最適な補償特性が得ら
れる。(2) The load current and the power supply current are detected at the same time, and an optimum compensation characteristic can be obtained by diagnosing the transfer characteristic of the system.
【図１】実施の形態１にかかるアクティブフィルタの制
御ブロック図。FIG. 1 is a control block diagram of an active filter according to a first embodiment.
【図２】実施の形態２にかかるアクティブフィルタの制
御ブロック図。FIG. 2 is a control block diagram of an active filter according to a second embodiment.
【図３】従来例にかかるアクティブフィルタの制御ブロ
ック図。FIG. 3 is a control block diagram of an active filter according to a conventional example.
【図４】他の従来例にかかるアクティブフィルタの制御
ブロック図。FIG. 4 is a control block diagram of an active filter according to another conventional example.
１…アクティブフィルタ（ＡＦ） ２…インバータ ３，５…ＦＦＴ（高速フーリエ変換）演算回路 ４，６…ディジタルフィルタ演算回路 ７…伝達特性演算回路 ８…振幅・位相調整回路 ９…各次高調波合成回路 ３１…３相２相変換回路 ３３，３４…ハイパスフィルタ ３５…２相３相変換回路 ４１2〜４１n…２次〜ｎ次バンドパスフィルタREFERENCE SIGNS LIST 1 Active filter (AF) 2 Inverter 3 5 FFT (fast Fourier transform) operation circuit 4 6 Digital filter operation circuit 7 Transfer characteristic operation circuit 8 Amplitude / phase adjustment circuit 9 Circuit 31 ... three-phase two-phase conversion circuit 33, 34 ... high-pass filter 35 ... two-phase three-phase conversion circuit 41 2 to 41 n ... second to n-th order band-pass filter
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.6 識別記号 ＦＩ Ｈ０２Ｍ 7/48 Ｈ０２Ｍ 7/48 Ｅ ──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. 6 Identification code FI H02M 7/48 H02M 7/48 E
Claims (2)
てインバータを制御して系統に補償電流を出力する電力
用アクティブフィルタにおいて、 負荷電流信号を高速フーリエ変換演算回路でフーリエ解
析し、 このフーリエ解析データをディジタルフィルタ演算して
負荷電流高調波各次成分の振幅，位相データを求め、 この分離された各次成分の振幅，位相データを基に補償
しようとする高調波各次成分を合成して前記補償電流指
令値を求めることを特徴とする電力用アクティブフィル
タの制御方法。1. A power active filter for obtaining a compensation current command value from a load current signal and controlling an inverter to output a compensation current to a system, wherein a Fourier analysis of the load current signal is performed by a fast Fourier transform operation circuit. The analysis data is digitally filtered to obtain the amplitude and phase data of each component of the load current harmonic, and the harmonic components to be compensated are synthesized based on the separated amplitude and phase data of each component. A method for controlling a power active filter, wherein the compensation current command value is obtained by the following method.
てインバータを制御して系統に補償電流を出力する電力
用アクティブフィルタにおいて、 負荷電流信号及び電源電流信号をそれぞれ高速フーリエ
変換演算回路でフーリエ解析し、 この各フーリエ解析データをそれぞれ第１及び第２のデ
ィジタルフィルタ演算回路でフィルタ演算して負荷電流
高調波及び電源電流高調波の各次成分の振幅，位相デー
タを求め、 この分離された負荷電流高調波及び電源高調波の各次成
分の振幅，位相データを伝達特性演算回路で比較して負
荷電流高調波と電源高調波の伝達特性を求め、 第１ディジタルフィルタ演算回路で分離された負荷電流
高調波各次成分の振幅，位相データを前記伝達特性で調
整し、 この調整されたデータを基に補償しようとする負荷電流
高調波の各次成分を合成して前記補償電流指令値を求め
ることを特徴とする電力用アクティブフィルタ。2. An active power filter for obtaining a compensation current command value from a load current signal and controlling an inverter to output a compensation current to a system, wherein the load current signal and the power supply current signal are each subjected to a Fourier transform by a fast Fourier transform operation circuit. The Fourier analysis data is filtered by first and second digital filter calculation circuits to obtain the amplitude and phase data of the respective harmonic components of the load current harmonic and the power supply current harmonic. The transfer characteristic calculation circuit compares the amplitude and phase data of each component of the load current harmonic and the power supply harmonic to determine the transfer characteristic of the load current harmonic and the power supply harmonic, and is separated by the first digital filter calculation circuit. The amplitude and phase data of each component of the load current harmonic are adjusted by the transfer characteristics, and the load to be compensated is adjusted based on the adjusted data. Active filter for power and obtaining the compensation current command value by combining the following components in the flow harmonics.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29827096A JP3528475B2 (en) | 1996-11-11 | 1996-11-11 | Active filter for power |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29827096A JP3528475B2 (en) | 1996-11-11 | 1996-11-11 | Active filter for power |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH10145972A true JPH10145972A (en) | 1998-05-29 |
| JP3528475B2 JP3528475B2 (en) | 2004-05-17 |
Family
ID=17857471
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP29827096A Expired - Lifetime JP3528475B2 (en) | 1996-11-11 | 1996-11-11 | Active filter for power |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3528475B2 (en) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ES2233193A1 (en) * | 2003-11-18 | 2005-06-01 | Enertron, S.L. | Active filter for use in nonlinear load network, has processor comprising block distortion analyzer, and logic block receiving output signal of current sensors for ordering features of inverter bridge |
| CN1305195C (en) * | 2003-06-09 | 2007-03-14 | 清华大学 | Active power filtering method with inversing capacitor regulation and branch impendance controlled decoupling |
| JP2008306829A (en) * | 2007-06-07 | 2008-12-18 | Meidensha Corp | Harmonic current compensator |
| JP2009213322A (en) * | 2008-03-06 | 2009-09-17 | Yanmar Co Ltd | Distributed power supply system |
| JP2010166719A (en) * | 2009-01-16 | 2010-07-29 | Mitsubishi Electric Corp | Motor drive control device, compressor, blower, air conditioner, and refrigerator or freezer |
| JP2010187521A (en) * | 2009-01-16 | 2010-08-26 | Mitsubishi Electric Corp | Motor drive controller, compressor, blower, air conditioner and refrigerator or freezer |
| JP2010288437A (en) * | 2009-05-13 | 2010-12-24 | Meidensha Corp | Control method for power converting device, uninterruptible power supply device, and parallel instantaneous-voltage-drop compensation device |
| JP2012151963A (en) * | 2011-01-18 | 2012-08-09 | Daikin Ind Ltd | Power conversion device |
| DE102014208195A1 (en) | 2013-05-01 | 2014-11-06 | Toshiba Kikai Kabushiki Kaisha | Inverter device and inverter generator |
| CN104635140A (en) * | 2014-12-29 | 2015-05-20 | 国家电网公司 | Low-voltage active power filter testing device and testing method thereof |
| CN104833853A (en) * | 2015-05-14 | 2015-08-12 | 电子科技大学 | Frequency-adaptive slide window DFT harmonic wave detection method |
-
1996
- 1996-11-11 JP JP29827096A patent/JP3528475B2/en not_active Expired - Lifetime
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1305195C (en) * | 2003-06-09 | 2007-03-14 | 清华大学 | Active power filtering method with inversing capacitor regulation and branch impendance controlled decoupling |
| ES2233193A1 (en) * | 2003-11-18 | 2005-06-01 | Enertron, S.L. | Active filter for use in nonlinear load network, has processor comprising block distortion analyzer, and logic block receiving output signal of current sensors for ordering features of inverter bridge |
| JP2008306829A (en) * | 2007-06-07 | 2008-12-18 | Meidensha Corp | Harmonic current compensator |
| JP2009213322A (en) * | 2008-03-06 | 2009-09-17 | Yanmar Co Ltd | Distributed power supply system |
| JP2010166719A (en) * | 2009-01-16 | 2010-07-29 | Mitsubishi Electric Corp | Motor drive control device, compressor, blower, air conditioner, and refrigerator or freezer |
| JP2010187521A (en) * | 2009-01-16 | 2010-08-26 | Mitsubishi Electric Corp | Motor drive controller, compressor, blower, air conditioner and refrigerator or freezer |
| JP2010288437A (en) * | 2009-05-13 | 2010-12-24 | Meidensha Corp | Control method for power converting device, uninterruptible power supply device, and parallel instantaneous-voltage-drop compensation device |
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| DE102014208195A1 (en) | 2013-05-01 | 2014-11-06 | Toshiba Kikai Kabushiki Kaisha | Inverter device and inverter generator |
| CN104635140A (en) * | 2014-12-29 | 2015-05-20 | 国家电网公司 | Low-voltage active power filter testing device and testing method thereof |
| CN104833853A (en) * | 2015-05-14 | 2015-08-12 | 电子科技大学 | Frequency-adaptive slide window DFT harmonic wave detection method |
| CN104833853B (en) * | 2015-05-14 | 2017-08-11 | 电子科技大学 | A kind of adaptive sliding window DFT harmonic detecting methods of frequency |
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