JP3427656B2 - Control method of inverter for photovoltaic power generation - Google Patents
Control method of inverter for photovoltaic power generationInfo
- Publication number
- JP3427656B2 JP3427656B2 JP00812497A JP812497A JP3427656B2 JP 3427656 B2 JP3427656 B2 JP 3427656B2 JP 00812497 A JP00812497 A JP 00812497A JP 812497 A JP812497 A JP 812497A JP 3427656 B2 JP3427656 B2 JP 3427656B2
- Authority
- JP
- Japan
- Prior art keywords
- inverter
- current
- output
- transformer
- voltage
- 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.)
- Expired - Fee Related
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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
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/56—Power conversion systems, e.g. maximum power point trackers
Landscapes
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
- Control Of Electrical Variables (AREA)
- Inverter Devices (AREA)
Description
【０００１】[0001]
【発明の属する技術分野】この発明は、太陽電池の出力
を受けこれを所定の交流に変換するインバータの出力電
圧を変圧器を介して適当な電圧に変圧し負荷に給電する
太陽光発電系において、前記変圧器の偏磁を防止し同変
圧器とその出力側コンデンサ間の共振電流の低減を図る
太陽光発電用インバータの制御方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar power generation system for converting an output voltage of an inverter which receives an output of a solar cell into a predetermined alternating current into a proper voltage through a transformer and supplies the load with power. The present invention relates to a method for controlling an inverter for photovoltaic power generation, which prevents magnetic bias of the transformer and reduces a resonance current between the transformer and a capacitor on the output side thereof.
【０００２】[0002]
【従来の技術】従来のこの種の太陽光発電系におけるイ
ンバータ制御としては図３に例示する制御ブロック図の
如く行われるものが知られている。なお、図４の主回路
図は、図３に示す太陽光発電系が外部交流電源系と負荷
を共通として並列運転するか、或いは、前記両電源系が
それぞれ単独に前記負荷に給電するか、何れの運転も可
能な如く構成された主回路の例示である。2. Description of the Related Art As a conventional inverter control in a solar power generation system of this type, there is known a control block diagram illustrated in FIG. In the main circuit diagram of FIG. 4, whether the solar power generation system shown in FIG. 3 operates in parallel with the external AC power supply system with a load in common, or whether the both power supply systems individually supply power to the load, It is an example of a main circuit configured so that any operation is possible.
【０００３】先ず、図４の主回路図において、１は太陽
電池、２Ａはインバータ装置、３は商用電源等の外部交
流電源、４は負荷である。ここに、インバータ装置２Ａ
において、２１は太陽電池１の直流出力を受けこれを所
定の電圧と周波数を有する交流に変換するインバータ、
２２はインバータ２１の出力電圧を所要の負荷給電用電
圧に変換する変圧器、２３はリアクトル、２４は変圧器
２２を経由したインバータ２１の出力平滑用のコンデン
サ、２５はインバータ出力平滑系に発生する共振電流抑
制用の制動抵抗である。First, in the main circuit diagram of FIG. 4, 1 is a solar cell, 2A is an inverter device, 3 is an external AC power source such as a commercial power source, and 4 is a load. Here, the inverter device 2A
In the figure, 21 is an inverter that receives the DC output of the solar cell 1 and converts this to AC having a predetermined voltage and frequency,
Reference numeral 22 is a transformer for converting the output voltage of the inverter 21 into a required load power supply voltage, 23 is a reactor, 24 is a capacitor for smoothing the output of the inverter 21 via the transformer 22, and 25 is generated in the inverter output smoothing system. It is a braking resistor for suppressing resonance current.
【０００４】また、ＭＣは外部交流電源３とインバータ
２１等から成る前記の太陽光発電系との並列運転用の電
磁接触器、ＣＯＳは前記太陽光発電系と外部交流電源３
とがそれぞれ単独に負荷４に給電する場合の給電経路切
替え用の切替開閉器であり、ＣＢ1 〜ＣＢ3 は遮断器で
ある。即ち、電磁接触器ＭＣを開路し、切替開閉器ＣＯ
Ｓを変圧器２２の出力側にて閉路すれば前記太陽光発電
系による負荷４への単独給電となり、また、前記ＭＣを
開路し、前記ＣＯＳを外部交流電源３側にて閉路すれば
この外部交流電源３による負荷４への単独給電となり、
更に、前記のＣＯＳを変圧器２２の出力側にて閉路し前
記ＭＣを前記の太陽光発電系と外部交流電源系との同期
状態にて閉路すればこれら太陽光発電系と外部交流電源
３両者による負荷４への給電となる。Further, MC is an electromagnetic contactor for parallel operation of the external AC power supply 3 and the solar power generation system including the inverter 21 and the like, and COS is the solar power generation system and the external AC power supply 3
And CB3 to CB3 are switching switches for switching the power supply paths when power is independently supplied to the load 4. That is, the electromagnetic contactor MC is opened and the switching switch CO
If S is closed on the output side of the transformer 22, it will be the sole power supply to the load 4 by the solar power generation system, and if the MC is opened and the COS is closed on the external AC power source 3 side, this external The AC power supply 3 will be the sole power supply to the load 4,
Further, if the COS is closed at the output side of the transformer 22 and the MC is closed in synchronization with the solar power generation system and the external AC power supply system, both the solar power generation system and the external AC power supply 3 are connected. Is to supply power to the load 4.
【０００５】なお、前記の太陽光発電系は外部交流電源
３との並列運転を行うために、インバータ２１は、その
出力周波数と変圧器２２で変圧される出力電圧において
外部交流電源３と等しくなる如く制御される。次に、図
３の制御ブロック図は、図４に示す太陽光発電系主回路
のインバータ２１に対する制御系の構成を示すものであ
る。従って、図３に示す主回路要素に関する説明は図４
の場合と同一であり、ここでは省略する。Since the above-mentioned photovoltaic power generation system operates in parallel with the external AC power supply 3, the inverter 21 has the same output frequency and output voltage transformed by the transformer 22 as the external AC power supply 3. Is controlled as follows. Next, the control block diagram of FIG. 3 shows a configuration of a control system for the inverter 21 of the solar power generation system main circuit shown in FIG. Therefore, the description of the main circuit elements shown in FIG.
Since it is the same as the case of, the description thereof is omitted here.
【０００６】図３において、λ設定器３１はＰＷＭ制御
（パルス幅変調制御）における制御パラメータであるλ
を設定するものである。ここに、パラメータλはインバ
ータの所要の出力電圧とその振幅が比例し周波数が同一
である正弦波指令信号の振幅ＶM と三角波搬送信号の振
幅ＶC との比（λ＝ＶM ／ＶC ）で規定される。また、
オフセット設定器３８は変圧器２２の偏磁成分をなすイ
ンバータ出力中の直流分を消滅させるために前記正弦波
指令信号の零レベル移行幅を設定するものであり、正弦
波発生器３２は前記パラメータλにより指定された振幅
を有し且つ前記設定器３８により指定された幅の零レベ
ル移行がなされた正弦波を前記のＰＷＭ制御における正
弦波指令信号として出力するものである。In FIG. 3, a λ setter 31 is a control parameter λ in the PWM control (pulse width modulation control).
Is to be set. Here, the parameter λ is a ratio (λ = V M / V C) between the amplitude V M of the sine wave command signal and the amplitude V C of the triangular wave carrier signal whose amplitude is proportional to the required output voltage of the inverter and whose frequency is the same. ). Also,
The offset setter 38 sets the zero level shift width of the sine wave command signal in order to eliminate the direct current component in the output of the inverter that forms the biased magnetic component of the transformer 22, and the sine wave generator 32 uses the parameter. A sine wave having an amplitude designated by λ and having a width shifted to the zero level designated by the setting unit 38 is output as a sine wave command signal in the PWM control.
【０００７】また、瞬時ＡＶＲ３３は、正弦波発生器３
２の出力する正弦波指令信号と計器用変圧器ＰＴにより
検出された負荷電圧ＶACとの偏差を入力としこの偏差の
修正指令を前記正弦波指令信号の各波形毎に出力する瞬
時動作形の自動電圧調整器であって、前記の電圧偏差修
正指令は正弦波発生器３２の出力する正弦波指令信号に
加算され、新たに前記ＰＷＭ制御における修正された正
弦波指令信号が形成される。The instantaneous AVR 33 has a sine wave generator 3
2 is an instantaneous operation type in which a deviation between the sine wave command signal output by the instrument 2 and the load voltage V AC detected by the instrument transformer PT is input and a correction command for this deviation is output for each waveform of the sine wave command signal. In the automatic voltage regulator, the voltage deviation correction command is added to the sine wave command signal output from the sine wave generator 32 to newly form a corrected sine wave command signal in the PWM control.
【０００８】次に、三角波発生器３５は前記パラメータ
λにより規定された振幅を有し所定の搬送周波数にて変
化する三角波搬送信号をＰＷＭ制御における前記正弦波
指令信号に対する比較信号として出力するものである。
また、ＰＷＭ３６はパルス幅変調制御回路であって、前
記の正弦波指令信号と三角波搬送信号との大小比較演算
の結果に従い各パルス幅が変調されたパルス列をインバ
ータ２１に入力される太陽電池出力直流電圧の断続基本
信号として出力するものである。Next, the triangular wave generator 35 outputs a triangular wave carrier signal having an amplitude defined by the parameter λ and changing at a predetermined carrier frequency as a comparison signal to the sine wave command signal in the PWM control. is there.
The PWM 36 is a pulse width modulation control circuit, which outputs a pulse train whose pulse widths are modulated to the inverter 21 according to the result of the magnitude comparison operation of the sine wave command signal and the triangular wave carrier signal. It is output as an intermittent basic signal of voltage.
【０００９】更に、ゲート信号分配器３７は前記ＰＷＭ
回路の出力するパルス幅変調されたパルス列をインバー
タ２１の出力相数に従う電気的位相差，例えば３相出力
時には電気角１２０度，の各相間位相差を有する３組の
パルス列に変成し、前記インバータ主回路における各相
スイッチング素子に対する断続制御信号として出力する
ものである。Further, the gate signal distributor 37 is the PWM
The pulse width modulated pulse train output from the circuit is transformed into three sets of pulse trains having an electrical phase difference according to the number of output phases of the inverter 21, for example, an electrical angle of 120 degrees when outputting three phases, and three sets of pulse trains having the phase difference. It is output as an intermittent control signal for each phase switching element in the main circuit.
【００１０】[0010]
【発明が解決しようとする課題】一般に、変圧器の偏磁
はその巻線を通過し鉄心励磁電流となる交流電流に直流
分が重畳することに起因して発生する。この励磁電流中
の直流分はその重畳方向の励磁を強めて鉄心励磁におけ
る対称性を崩して変圧器２次出力電圧の波形を歪ませ
る。即ち、変圧器２次出力電圧における高調波成分発生
の原因をなす。In general, the demagnetization of a transformer occurs due to the superposition of a direct current component on an alternating current that passes through its winding and becomes an iron core exciting current. The direct current component in this exciting current strengthens the excitation in the superimposing direction, destroys the symmetry in the iron core excitation, and distorts the waveform of the transformer secondary output voltage. That is, it causes the generation of higher harmonic components in the secondary output voltage of the transformer.
【００１１】なお、本発明に関しては、前記の変圧器励
磁電流はその１次側交流電流である太陽電池出力変換用
インバータの出力電流である。一方、前記の如く従来の
太陽光発電用インバータの制御方法は、前記λ設定器に
よる振幅指定と、前記オフセット設定器により，変圧器
偏磁の原因をなす前記インバータ出力電流中の直流分に
よる零レベル移行幅に対応するオフセット設定と、に従
いその振幅方向に非対称に形成された正弦波指令信号に
対し負荷電圧を等しくする如く制御を行うものである。
なお、前記の負荷電圧の形成要因をなす負荷電流状態を
前記正弦波指令信号の形成に配慮することは行われてい
ない。With respect to the present invention, the transformer exciting current is the output current of the solar cell output converting inverter which is the primary side alternating current. On the other hand, as described above, the conventional method for controlling a photovoltaic power generation inverter uses the λ setting device to specify the amplitude and the offset setting device to eliminate zero due to the direct current component in the inverter output current that causes transformer bias magnetization. According to the offset setting corresponding to the level transition width, control is performed so that the load voltage becomes equal to the sine wave command signal that is formed asymmetrically in the amplitude direction.
It should be noted that no consideration is given to the formation of the sine wave command signal with respect to the load current state which is a factor for forming the load voltage.
【００１２】しかしながら、前記の変圧器偏磁の原因を
なすインバータ出力電流中の直流分は、インバータ主回
路のブリッジ構成における上下各アーム素子のスイッチ
ング特性の差異或いはスイッチング指令信号系の時間特
性の差異等に起因して発生するものであり、その大きさ
は前記インバータの負荷状態或いは入力電圧の変動に伴
って変化し、一定値ではない。However, the direct current component in the inverter output current, which is the cause of the transformer bias magnetism, is different in the switching characteristics of the upper and lower arm elements in the bridge configuration of the inverter main circuit or in the time characteristic of the switching command signal system. And the like, and the magnitude thereof varies with the load state of the inverter or the fluctuation of the input voltage, and is not a constant value.
【００１３】従って、インバータ出力電流中の直流分を
一定と見做し前記正弦波指令信号に対する零レベル移行
幅を定値となす固定オフセット設定を行う従来の制御方
法では、負荷状態の変化或いは入力電圧の変動に伴うオ
フセットレベルの変化に対応することが出来ず、変圧器
２次出力電圧の波形歪みとこれに伴う２次側高調波の発
生を来し、更に、変圧器洩れリアクタンスと出力平滑用
コンデンサとで形成するＬＣ共振系における前記高調波
による共振電流の増大を招く危険があった。Therefore, in the conventional control method in which the direct current component in the inverter output current is regarded as constant and the fixed offset setting in which the zero level transition width for the sine wave command signal is a constant value is set, the load state change or the input voltage is changed. It is not possible to cope with the change in the offset level due to fluctuations in the output voltage, resulting in the waveform distortion of the secondary output voltage of the transformer and the generation of secondary side harmonics accompanying it, and further, the transformer leakage reactance and output smoothing. There is a risk of causing an increase in the resonance current due to the higher harmonics in the LC resonance system formed with the capacitor.
【００１４】上記に鑑みこの発明は、太陽電池の出力を
受けてこれを所定の交流に変換するインバータの出力電
圧を変圧器を介して適当な電圧に変圧し負荷に給電する
太陽光発電系において、前記変圧器の偏磁を防止すると
共に，同変圧器とその出力側コンデンサ間の共振電流の
低減を図るインバータ制御方法の提供を目的とするもの
である。In view of the above, the present invention relates to a solar power generation system in which an output voltage of an inverter which receives an output of a solar cell and converts the output into a predetermined alternating current is transformed into an appropriate voltage through a transformer to supply power to a load. It is an object of the present invention to provide an inverter control method for preventing the demagnetization of the transformer and reducing the resonance current between the transformer and the capacitor on the output side thereof.
【００１５】[0015]
【課題を解決するための手段】上記目的を達成するため
に、この発明の太陽光発電用インバータの制御方法にお
いて、
１）請求項１の発明は、太陽電池の直流出力を受けてこ
れを所定の交流に変換するインバータと、このインバー
タの出力電圧を所要の負荷給電用電圧に変換する変圧器
と、この変圧器の２次側に設けられた変圧器出力平滑用
コンデンサとを以て構成された太陽光発電系における前
記インバータに対して、所要負荷電圧とその振幅が比例
し且つその周波数が同一の正弦波指令信号と前記負荷電
圧の検出信号との間の偏差を入力とし前記指令信号の各
波毎にその波形修正信号を出力する瞬時動作形自動電圧
調整手段の出力を前記指令信号に加算して得た修正され
た正弦波指令信号と三角波搬送信号との比較によるパル
ス幅変調制御を行い、インバータ出力電圧制御を介し前
記負荷電圧をその所要値に維持する如く回路構成された
太陽光発電系における前記インバータの制御方法におい
て、前記インバータと変圧器間におけるインバータ出力
電流の検出手段と、前記平滑用コンデンサと負荷間にお
ける負荷電流の検出手段と、検出された前記のインバー
タ出力電流と変圧比換算された前記負荷電流との間の偏
差をその入力とする自動電流調整手段と、を設け、この
自動電流調整手段の出力信号を前記のパルス幅変調制御
における修正された正弦波指令信号に対する加算補正信
号となすものとする。In order to achieve the above object, in the method for controlling a solar power generation inverter according to the present invention, 1) the invention of claim 1 receives a direct current output of a solar cell and sets it to a predetermined value. A solar converter including an inverter for converting into AC current, a transformer for converting an output voltage of the inverter into a required load power supply voltage, and a transformer output smoothing capacitor provided on a secondary side of the transformer. With respect to the inverter in the photovoltaic system, each wave of the command signal is input with a deviation between a sine wave command signal having a required load voltage and its amplitude proportional and having the same frequency and a detection signal of the load voltage. A pulse width modulation control by comparing the corrected sine wave command signal obtained by adding the output of the instantaneous operation type automatic voltage adjusting means for outputting the waveform correction signal for each time with the command signal and the triangular wave carrier signal. Control method for controlling the inverter in a photovoltaic power generation system configured to maintain the load voltage at its required value through inverter output voltage control, the inverter output current detecting means between the inverter and the transformer. A means for detecting a load current between the smoothing capacitor and the load, and an automatic current adjusting means having as an input a deviation between the detected inverter output current and the load current converted into a transformation ratio, And the output signal of the automatic current adjusting means is used as an addition correction signal for the corrected sine wave command signal in the pulse width modulation control.
【００１６】２）請求項２の発明は、請求項１記載の太
陽光発電用インバータの制御方法において、前記インバ
ータ出力電流の検出手段を、ホール素子をその基本要素
とするホール素子形変流器となすものとする。
３）請求項３の発明は、請求項１記載の太陽光発電用イ
ンバータの制御方法において、前記インバータ出力電流
の検出手段を分流器をその基本要素として構成するもの
とする。2) The invention according to claim 2 is the method for controlling an inverter for photovoltaic power generation according to claim 1, wherein the detecting means of the inverter output current has a hall element as a basic element thereof. And 3) According to the invention of claim 3, in the method for controlling an inverter for photovoltaic power generation according to claim 1, the detecting means of the inverter output current comprises a shunt as a basic element thereof.
【００１７】上記の如くこの発明は、インバータ出力電
流と変圧比換算された負荷電流間の偏差として、前記の
インバータ出力電流中の直流分と変圧器出力側において
形成されるＬＣ共振系における共振電流との両者の合成
状態を検出し、この検出値を自動電流調整器を介して量
的及び時間的に適値となされた電流分補正信号として変
成し、この電流分補正信号を正弦波発生器の出力する正
弦波指令信号に対して前記の電圧分補正信号と共に加算
して得た修正された正弦波指令信号を基準としたＰＷＭ
制御を行ってインバータ出力電圧の形成を行うことによ
り、前記変圧器偏磁の原因をなすインバータ出力電流中
の直流分と、前記偏磁による波形歪みに起因する高調波
による前記ＬＣ共振系共振電流との両者の低減或いは除
去を図るものである。As described above, according to the present invention, as the deviation between the inverter output current and the load current converted into the transformer ratio, the direct current component in the inverter output current and the resonance current in the LC resonance system formed on the transformer output side are obtained. And the combined state of both of them is detected, and this detected value is transformed through an automatic current regulator as a current component correction signal that has been made a proper value quantitatively and temporally, and this current component correction signal is converted into a sine wave generator. PWM based on the corrected sine wave command signal obtained by adding the above voltage correction signal to the sine wave command signal output by
By performing the control to form the inverter output voltage, the direct current component in the inverter output current that causes the transformer bias magnetization and the LC resonance system resonance current due to the harmonics caused by the waveform distortion due to the bias magnetization. Both are intended to be reduced or eliminated.
【００１８】更にまた、請求項２或いは請求項３による
如く、直流分を含む前記インバータ出力電流の検出手段
として、ホール素子形変流器、或いは分流器をその基本
要素として演算増幅器等を以て構成した分流器形を用い
ることにより、直流分含有の如何を問わず正確な電流検
出を図っている。Furthermore, as described in claim 2 or claim 3, as a means for detecting the inverter output current including a DC component, a Hall element type current transformer or a shunt is used as a basic element of the operational amplifier. By using a shunt type, accurate current detection is achieved regardless of the presence of DC component.
【００１９】[0019]
【発明の実施の形態】以下この発明の実施例を図１の制
御ブロック図と図２の主回路図とに従い説明する。な
お、図１と図２及び従来技術の実施例を示す前述の図３
と図４とにおいては、同一機能の構成要素に対しては同
一の表示符号を付している。先ず、図２に示す太陽光発
電系の主回路図は、前記図４と比較し、インバータ２１
と変圧器２２との間に設けたインバータ出力電流検出用
の変流器ＣＴ1 と、ＣＯＳを介し変圧器２２と負荷４と
の間に設けた負荷電流検出用の変流器ＣＴ2とを加える
と共に各ＣＴの出力をインバータ２１に印加し、更にコ
ンデンサ２４に直列接続された共振電流抑制用の抵抗２
５を削除した構成をなすものである。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the control block diagram of FIG. 1 and the main circuit diagram of FIG. 1 and 2 and the above-mentioned FIG. 3 showing the embodiment of the prior art.
4 and FIG. 4, components having the same function are designated by the same reference numeral. First, the main circuit diagram of the solar power generation system shown in FIG.
And a transformer CT1 for detecting an inverter output current provided between the transformer 22 and the transformer 22, and a transformer CT2 for detecting a load current provided between the transformer 22 and the load 4 via COS. The output of each CT is applied to the inverter 21, and the resonance current suppressing resistor 2 connected in series with the capacitor 24 is further provided.
5 is deleted.
【００２０】次に、図１の制御ブロック図は、前記図２
の主回路図における変更を受け前記図３と比較すれば、
変流器ＣＴ1 によるインバータ出力電流の検出信号Ｉ
INV と変流器ＣＴ2 による負荷電流の検出信号ＩACとの
偏差（ＩAC−ＩINV ）を入力とする自動電流調整器であ
るＡＣＲ３４を設けると共に、正弦波発生器３２と瞬時
ＡＶＲ３３両者の出力の和として形成される正弦波指令
信号に対してＡＣＲ３４の出力を加算することにより、
インバータ出力電圧形成用のＰＷＭ制御における新たな
修正された正弦波指令信号を得る構成をなすものであ
る。Next, the control block diagram of FIG. 1 is shown in FIG.
Compared to the above-mentioned FIG. 3 due to the change in the main circuit diagram of
Inverter output current detection signal I by current transformer CT1
Provided with a ACR34 is an automatic current regulator which receives a detection signal I AC and deviation of the load current by INV and the current transformer CT2 (I AC -I INV), a sine wave generator 32 and the instantaneous AVR33 both output By adding the output of the ACR 34 to the sine wave command signal formed as the sum of
The configuration is such that a new modified sine wave command signal is obtained in the PWM control for forming the inverter output voltage.
【００２１】即ち、前記正弦波指令信号に対して前記電
流偏差（ＩAC−ＩINV ）に対応する電流分補正を行うこ
とにより、インバータの運転状態に従って不規則に変化
して変圧器偏磁の原因をなすインバータ出力電流中の直
流分に追従しインバータ出力電圧における零レベル移行
幅を自動的に適値に選定する自動オフセット設定動作が
可能となり、前記インバータ出力電流中の直流分の低減
に伴う変圧器２次出力電圧の波形歪みが低減或いは除去
され、また、これに伴い、前記変圧器２次出力電圧にお
ける含有高調波分も低減或いは除去されて、変圧器洩れ
リアクタンスと平滑用コンデンサとで形成するＬＣ共振
系における前記高調波による共振電流も低減或いは除去
されることになる。[0021] That is, by performing the current component correction corresponding to the current deviation relative to the sine-wave command signal (I AC -I INV), irregularly changed by the transformer magnetic bias of according the operation state of the inverter It is possible to perform an automatic offset setting operation that follows the direct current component in the inverter output current and automatically selects the zero level transition width in the inverter output voltage to an appropriate value. The waveform distortion of the secondary output voltage of the transformer is reduced or removed, and the harmonic content contained in the secondary output voltage of the transformer is also reduced or removed accordingly, so that the transformer leakage reactance and the smoothing capacitor are formed. The resonance current due to the harmonics in the LC resonance system to be formed is also reduced or eliminated.
【００２２】更に、その回路構成を図示するものではな
いが、電流検出手段として図１或いは図２に示す各ＣＴ
の内容は、ホール素子を基本検出素子としこれに所要の
演算増幅器を組み合わせて構成したホール素子形変流
器、或いは、分流器をその基本検出要素としこれに所要
の演算増幅器を組み合わせて構成した分流器形変流器で
ある。Further, although not shown in the drawing, the circuit configuration of each CT shown in FIG. 1 or 2 is used as a current detecting means.
The contents of are the Hall element type current transformer which is configured by combining a hall element as a basic detection element and a required operational amplifier, or a shunt current transformer as its basic detection element and configured by combining the required operational amplifier. It is a shunt type current transformer.
【００２３】[0023]
【発明の効果】この発明によれば、太陽電池の出力を受
けてこれを所定の交流に変換するインバータと、このイ
ンバータの出力電圧を所要の負荷給電用電圧に変換する
変圧器と、変圧器出力平滑用コンデンサとを以て構成さ
れた太陽光発電系における前記インバータに対して、所
要の負荷電圧とその振幅が比例し且つその周波数が同一
の正弦波指令信号と前記負荷電圧の検出信号間の偏差を
入力とする瞬時動作形の自動電圧調整手段の出力を前記
正弦波指令信号の各波毎に加算して得た修正された正弦
波指令信号と三角波搬送信号との比較によるパルス幅変
調（ＰＷＭ）制御を行う前記インバータの制御方法にお
いて、請求項１の如く、前記インバータの出力電流の検
出信号と前記変圧器の変圧比により換算された前記負荷
電流の検出信号間の偏差をその入力とする自動電流調整
手段の出力信号を前記の正弦波指令信号に加算し、前記
ＰＷＭ制御において三角波搬送信号と比較すべき正弦波
指令信号に対し前記電流偏差に対応する電流分補正を行
うことにより、変圧器偏磁の原因をなすインバータ出力
電流中の直流分の変化に追従しインバータ出力電圧にお
ける零レベル移行幅を自動的に適値に選定する自動オフ
セット設定動作が可能となり、前記の如き直流分の低減
に伴う変圧器２次出力電圧の波形歪みが低減或いは除去
され、これに伴い変圧器２次出力電圧における含有高調
波分も低減或いは除去され、従って、変圧器洩れリアク
タンスと平滑用コンデンサとで形成するＬＣ共振系にお
ける前記高調波による共振電流も低減或いは除去される
ことになる。更に、請求項２或いは請求項３の如く、直
流分を含むインバータ出力電流の検出手段として、ホー
ル素子形変流器、或いは分流器をその基本要素として演
算増幅器等を以て構成した分流器形を用いることによっ
て、直流電流或いは高調波電流を含めて正確な電流検出
を行うことが可能となる。According to the present invention, an inverter for receiving an output of a solar cell and converting the output into a predetermined alternating current, a transformer for converting an output voltage of the inverter into a required load power supply voltage, and a transformer Deviation between a sine wave command signal and a detection signal of the load voltage in which the required load voltage and its amplitude are proportional and the frequency is the same with respect to the inverter in the photovoltaic power generation system configured with an output smoothing capacitor. Pulse width modulation (PWM) by comparing the modified sine wave command signal obtained by adding the output of the instantaneous voltage automatic voltage adjusting means for each input of the sine wave command signal with the triangular wave carrier signal. ) In the method of controlling the inverter for controlling, between the detection signal of the output current of the inverter and the detection signal of the load current converted by the transformation ratio of the transformer as in claim 1. An output signal of an automatic current adjusting means having a deviation as its input is added to the sine wave command signal, and a current component correction corresponding to the current deviation is made to the sine wave command signal to be compared with the triangular wave carrier signal in the PWM control. By doing so, it becomes possible to perform an automatic offset setting operation that automatically changes the zero level transition width in the inverter output voltage to an appropriate value by following the change in the direct current component in the inverter output current that causes the transformer bias magnetization. As described above, the waveform distortion of the secondary output voltage of the transformer due to the reduction of the direct current component is reduced or eliminated, and the contained harmonic component in the secondary output voltage of the transformer is also reduced or eliminated, and accordingly, the transformer leakage reactance. Also, the resonance current due to the higher harmonics in the LC resonance system formed by the smoothing capacitor is reduced or eliminated. Further, as described in claim 2 or claim 3, as the detecting means of the inverter output current including the direct current component, a Hall element type current transformer or a shunt type in which an operational amplifier or the like is used as a basic element of the shunt is used. As a result, it becomes possible to accurately detect the current including the direct current or the harmonic current.
【図１】この発明の実施例を示す制御ブロック図FIG. 1 is a control block diagram showing an embodiment of the present invention.
【図２】この発明の実施例を示す主回路図FIG. 2 is a main circuit diagram showing an embodiment of the present invention.
【図３】従来技術の実施例を示す制御ブロック図FIG. 3 is a control block diagram showing an embodiment of the prior art.
【図４】従来技術の実施例を示す主回路図FIG. 4 is a main circuit diagram showing an example of a conventional technique.
１ 太陽電池 ２ インバータ装置 ２Ａ インバータ装置 ３ 外部交流電源 ４ 負荷 ２１ インバータ ２２ 変圧器 ２３ リアクトル ２４ コンデンサ ２５ 抵抗 ３１ λ設定器 ３２ 正弦波発生器 ３３ 瞬時ＡＶＲ（瞬時動作形自動電圧調整器） ３４ ＡＣＲ（自動電流調整器） ３５ 三角波発生器 ３６ ＰＷＭ（パルス幅変調制御回路） ３７ ゲート信号分配器 ３８ オフセット設定器 ＣＢn 遮断器（ｎ＝１〜３) ＣＯＳ 切替開閉器 ＣＴn 計器用変流器（ｎ＝１，２) ＭＣ 電磁接触器 ＰＴ 計器用変圧器1 Solar Battery 2 Inverter Device 2A Inverter Device 3 External AC Power Supply 4 Load 21 Inverter 22 Transformer 23 Reactor 24 Capacitor 25 Resistor 31 λ Setting Device 32 Sine Wave Generator 33 Instantaneous AVR (Instantaneous Action Automatic Voltage Regulator) 34 ACR ( Automatic current regulator) 35 Triangular wave generator 36 PWM (Pulse width modulation control circuit) 37 Gate signal distributor 38 Offset setting device CB n Circuit breaker (n = 1 to 3) COS switching switch CT n Current transformer for instrument ( n = 1, 2) MC Electromagnetic contactor PT Meter transformer
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) H02M 7/48 G05F 1/44 G05F 1/67 H02J 7/35 ─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. 7 , DB name) H02M 7/48 G05F 1/44 G05F 1/67 H02J 7/35
Claims (3)
交流に変換するインバータと、このインバータの出力電
圧を所要の負荷給電用電圧に変換する変圧器と、この変
圧器の２次側に設けられた変圧器出力平滑用コンデンサ
とを以て構成された太陽光発電系における前記インバー
タに対し、所要負荷電圧とその振幅が比例し且つその周
波数が同一の正弦波指令信号と前記負荷電圧の検出信号
との間の偏差を入力とし前記指令信号の各波毎にその波
形修正信号を出力する瞬時動作形自動電圧調整手段の出
力を前記指令信号に加算して得た修正された正弦波指令
信号と三角波搬送信号との比較によるパルス幅変調制御
を行い、インバータ出力電圧制御を介し前記負荷電圧を
その所要値に維持する如く回路構成された太陽光発電系
における前記インバータの制御方法において、前記のイ
ンバータと変圧器間におけるインバータ出力電流の検出
手段と、前記の平滑用コンデンサと負荷間における負荷
電流の検出手段と、検出された前記のインバータ出力電
流と変圧比換算された前記負荷電流との間の偏差をその
入力とする自動電流調整手段と、を設け、この自動電流
調整手段の出力信号を前記のパルス幅変調制御における
修正された正弦波指令信号に対する加算補正信号となす
ことを特徴とする太陽光発電用インバータの制御方法。1. An inverter for receiving a direct current output of a solar cell and converting it into a predetermined alternating current, a transformer for converting an output voltage of the inverter into a required load power supply voltage, and a secondary side of the transformer. The detection of the sine wave command signal and the load voltage whose amplitude is proportional to the required load voltage and whose amplitude is the same as that of the inverter in the photovoltaic power generation system configured with the transformer output smoothing capacitor provided in A corrected sine wave command signal obtained by adding the output of the instantaneous operation type automatic voltage adjusting means for inputting the deviation from the signal and outputting the waveform correction signal for each wave of the command signal to the command signal And a triangular wave carrier signal for pulse width modulation control, and the inverter output voltage control is used to maintain the load voltage at its required value. In the control method of the inverter, a means for detecting an inverter output current between the inverter and the transformer, a means for detecting a load current between the smoothing capacitor and a load, the detected inverter output current and a transformer ratio. An automatic current adjusting means having as input the deviation from the converted load current, and adding the output signal of the automatic current adjusting means to the corrected sine wave command signal in the pulse width modulation control. A control method for a photovoltaic power generation inverter, characterized by using a correction signal.
制御方法において、前記インバータ出力電流の検出手段
を、ホール素子をその基本要素とするホール素子形変流
器とすることを特徴とする太陽光発電用インバータの制
御方法。2. The method for controlling an inverter for photovoltaic power generation according to claim 1, wherein the inverter output current detecting means is a hall element type current transformer having a hall element as its basic element. Photovoltaic inverter control method.
制御方法において、前記インバータ出力電流の検出手段
を、分流器をその基本要素として構成したことを特徴と
する太陽光発電用インバータの制御方法。3. The control method for a photovoltaic power generation inverter according to claim 1, wherein the means for detecting the inverter output current comprises a shunt as a basic element. Method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP00812497A JP3427656B2 (en) | 1997-01-21 | 1997-01-21 | Control method of inverter for photovoltaic power generation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP00812497A JP3427656B2 (en) | 1997-01-21 | 1997-01-21 | Control method of inverter for photovoltaic power generation |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH10210760A JPH10210760A (en) | 1998-08-07 |
| JP3427656B2 true JP3427656B2 (en) | 2003-07-22 |
Family
ID=11684552
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP00812497A Expired - Fee Related JP3427656B2 (en) | 1997-01-21 | 1997-01-21 | Control method of inverter for photovoltaic power generation |
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| Country | Link |
|---|---|
| JP (1) | JP3427656B2 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5560730B2 (en) * | 2009-05-13 | 2014-07-30 | 株式会社明電舎 | Power converter control method, uninterruptible power supply, parallel sag compensator |
| JP6018792B2 (en) * | 2012-04-27 | 2016-11-02 | 東芝三菱電機産業システム株式会社 | Power converter control method |
-
1997
- 1997-01-21 JP JP00812497A patent/JP3427656B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH10210760A (en) | 1998-08-07 |
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