JPH08168266A - Method for controlling dc-ac converter - Google Patents
Method for controlling dc-ac converterInfo
- Publication number
- JPH08168266A JPH08168266A JP6305771A JP30577194A JPH08168266A JP H08168266 A JPH08168266 A JP H08168266A JP 6305771 A JP6305771 A JP 6305771A JP 30577194 A JP30577194 A JP 30577194A JP H08168266 A JPH08168266 A JP H08168266A
- Authority
- JP
- Japan
- Prior art keywords
- high frequency
- voltage
- output
- cycloconverter
- transformer
- 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.)
- Pending
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
- 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
- Inverter Devices (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】この発明は、例えば燃料電池,太
陽電池などの直流電源より得られる直流電力を絶縁され
た交流電力に変換する直交変換装置の制御方法に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a quadrature conversion device for converting DC power obtained from a DC power supply such as a fuel cell or a solar cell into insulated AC power.
【0002】[0002]
【従来の技術】図6に、この種の直交変換装置の構成図
を示す。図6において、1は燃料電池,太陽電池などの
直流電源、2は半導体スイッチ素子などから構成される
高周波インバータ、3は直流,交流電源間を絶縁する高
周波トランス、4は半導体スイッチ素子などから構成さ
れ、PWM制御した出力電圧パルスを出力するサイクロ
コンバータ、5は前記出力電圧パルスの該PWM周波数
成分を除去するフィルタ、6はこの直交変換装置の負荷
である。2. Description of the Related Art FIG. 6 shows a block diagram of an orthogonal transform device of this type. In FIG. 6, 1 is a DC power source such as a fuel cell or solar cell, 2 is a high frequency inverter composed of semiconductor switching elements, 3 is a high frequency transformer for insulating between DC and AC power sources, 4 is a semiconductor switching element, etc. The cycloconverter 5 outputs a PWM-controlled output voltage pulse, 5 is a filter for removing the PWM frequency component of the output voltage pulse, and 6 is a load of the orthogonal converter.
【0003】図7は、図6に示した直交変換装置の従来
の制御方法を示し、図7(イ)に示すように直流電源1
の直流電圧Edを高周波インバータ2により50%デュ
ーティで正負の交流電圧に変換し、この交流電圧で高周
波トランス3の一次側を励磁する。高周波トランス3の
出力を、図7(ロ)に示すようにサイクロコンバータ4
の制御回路によりPWM搬送波と正弦波の出力電圧指令
とによりPWM制御され、サイクロコンバータ4の出力
波形は図7(ハ)のようになり、フィルタ5の出力に
は、負荷6が要求する図7(ニ)に示す低周波の交流電
圧が発生する。FIG. 7 shows a conventional control method for the orthogonal transformation device shown in FIG. 6, and as shown in FIG.
The DC voltage Ed of is converted into a positive / negative AC voltage with a 50% duty by the high frequency inverter 2, and the primary side of the high frequency transformer 3 is excited by this AC voltage. The output of the high frequency transformer 3 is supplied to the cycloconverter 4 as shown in FIG.
The PWM control is performed by the control circuit of FIG. 7 by the PWM carrier wave and the output voltage command of the sine wave, the output waveform of the cycloconverter 4 is as shown in FIG. 7C, and the output of the filter 5 is required by the load 6. The low-frequency AC voltage shown in (d) is generated.
【0004】[0004]
【発明が解決しようとする課題】図7に示したように、
高周波インバータ2が50%デューティで正負の交流電
圧を出力し、サイクロコンバータ4はPWM制御による
波形整形を行っているので、サイクロコンバータ4が切
り出す電圧パルスの変調率λは、出力電圧の波高値をV
oとして、式(1)で表される。[Problems to be Solved by the Invention] As shown in FIG.
Since the high-frequency inverter 2 outputs a positive / negative AC voltage with a duty of 50% and the cycloconverter 4 performs waveform shaping by PWM control, the modulation factor λ of the voltage pulse cut out by the cycloconverter 4 is the peak value of the output voltage. V
It is represented by Formula (1) as o.
【0005】[0005]
【数1】 λ=Vo/Ed (λ≦1) …(1) すなわち、出力電圧の波高値Voを一定とすれば、変調
率λは直流電圧Edに反比例の関係となる。一方、高周
波トランス3は常時50%デューティで励磁されるた
め、高周波トランス3の最大磁束密度(Bmax)は、
直流電源1の直流電圧Edが最大となる点で発生する。## EQU00001 ## .lamda. = Vo / Ed (.lamda..ltoreq.1) (1) That is, if the peak value Vo of the output voltage is constant, the modulation factor .lamda. Is inversely proportional to the DC voltage Ed. On the other hand, since the high frequency transformer 3 is always excited with 50% duty, the maximum magnetic flux density (Bmax) of the high frequency transformer 3 is
It occurs at the point where the DC voltage Ed of the DC power supply 1 becomes maximum.
【0006】従って、従来の制御方法によると、直流電
圧Edが上昇するにつれて、変調率λは小さくなり、出
力電圧の波高値Voに関与しない高周波トランス3の励
磁分が大きくなり、特に燃料電池,太陽電池などのよう
に、電圧変動の大きい直流電源1をこの直交変換装置に
用いると、高周波トランス3の飽和磁束密度を直流電圧
Edの最大値で発生する磁束密度以上にする必要がある
ため、高周波トランス3が大形化し、コスト高になると
いう問題があった。Therefore, according to the conventional control method, as the DC voltage Ed increases, the modulation factor λ decreases, and the excitation component of the high frequency transformer 3 which is not related to the peak value Vo of the output voltage increases. If a DC power supply 1 with large voltage fluctuations such as a solar cell is used in this orthogonal converter, it is necessary to make the saturation magnetic flux density of the high frequency transformer 3 equal to or higher than the magnetic flux density generated at the maximum value of the DC voltage Ed. There is a problem that the high frequency transformer 3 becomes large and the cost becomes high.
【0007】この発明の目的は、上記問題点を解決する
直交変換装置の制御方法を提供することにある。An object of the present invention is to provide a control method for an orthogonal transform device that solves the above problems.
【0008】[0008]
【課題を解決するための手段】直流電圧を高周波の交流
電圧に変換する高周波インバータと、該高周波インバー
タの出力に接続される高周波トランスと、該高周波トラ
ンスの二次側に接続されるサイクロコンバータと、該サ
イクロコンバータの出力に接続されるフィルタとから構
成される直交変換装置の制御方法において、この第1の
発明では、PWM制御された前記サイクロコンバータの
出力電圧パルスのパルス幅に、前記高周波インバータの
正,負極性で発生する出力電圧パルスのパルス幅をそれ
ぞれ追従させ、また、第2の発明では、前記高周波イン
バータの正,負極性で発生する出力電圧パルスのパルス
幅を、前記直流電圧の変化に反比例させる。A high frequency inverter for converting a DC voltage into a high frequency AC voltage, a high frequency transformer connected to the output of the high frequency inverter, and a cycloconverter connected to the secondary side of the high frequency transformer. And a filter connected to the output of the cycloconverter, the first aspect of the present invention, wherein the high-frequency inverter has the pulse width of the PWM-controlled output voltage pulse of the cycloconverter. The pulse widths of the output voltage pulses generated in the positive and negative polarities are respectively followed, and in the second invention, the pulse widths of the output voltage pulses generated in the positive and negative polarities of the high frequency inverter are set to Make it inversely proportional to change.
【0009】[0009]
【作用】この第1の発明によれば、前述の直交変換装置
において、PWM制御されたサイクロコンバータの出力
電圧パルスを得るのと等しいパルス幅に、高周波インバ
ータの正,負極性で発生する出力電圧パルスのパルス幅
をそれぞれ追従させ、該高周波インバータが出力した電
圧で高周波トランスを励磁するので、不要な励磁期間が
無くなり該高周波トランスが小形化される。According to the first aspect of the present invention, in the above-mentioned orthogonal converter, the output voltage generated by the positive and negative polarities of the high frequency inverter has a pulse width equal to that of the output voltage pulse of the PWM-controlled cycloconverter. Since the pulse width of each pulse is made to follow and the high frequency transformer is excited by the voltage output by the high frequency inverter, an unnecessary excitation period is eliminated and the high frequency transformer is miniaturized.
【0010】また、第2の発明によれば、前述の直交変
換装置において、高周波インバータの正,負極性で発生
する出力電圧パルスのパルス幅を、直流電圧の変動に対
応して、すなわち該直流電圧が高いときには狭く、該直
流電圧が低いときには広くするので、高周波トランスの
不要な励磁期間が少なくなり該高周波トランスが小形化
される。According to the second aspect of the invention, in the above-mentioned quadrature converter, the pulse width of the output voltage pulse generated in the positive and negative polarities of the high frequency inverter corresponds to the fluctuation of the DC voltage, that is, the DC voltage. Since the voltage is narrow when the voltage is high and wide when the DC voltage is low, the unnecessary excitation period of the high frequency transformer is reduced, and the high frequency transformer is downsized.
【0011】[0011]
【実施例】以下に記載するこの発明の実施例において、
図6,図7に示した従来例と同一機能を有するものに
は、同一符号を付して説明を省略し、異なる機能を中心
に説明する。図1は、この発明の実施例を示す単相出力
の直交変換装置の主回路構成図であり、20は半導体ス
イッチ素子T1 〜T4 からなる高周波インバータ主回
路、40は半導体スイッチ素子S1 〜S4 からなるサイ
クロコンバータ主回路である。EXAMPLES In the examples of the present invention described below,
Those having the same functions as those of the conventional example shown in FIGS. 6 and 7 are designated by the same reference numerals, and the description thereof will be omitted. The different functions will be mainly described. FIG. 1 is a main circuit configuration diagram of a single-phase output quadrature conversion device showing an embodiment of the present invention, in which 20 is a high-frequency inverter main circuit including semiconductor switch elements T 1 to T 4 , and 40 is a semiconductor switch element S 1. It is a cycloconverter main circuit composed of S 4 to S 4 .
【0012】図1において、負荷6に正極性の電圧を出
力するときには、高周波トランス3の励磁極性が正の場
合(T1 ,T4 点弧)は、S1 ,S4 をオンさせ、高周
波トランス3の励磁極性が負の場合(T2 ,T3 点弧)
は、S2 ,S3 をオンさせる。また、負荷6に負極性の
電圧を出力するときには、高周波トランス3の励磁極性
が正の場合(T1 ,T4 点弧)は、S2 ,S3 をオンさ
せ、高周波トランス3の励磁極性が負の場合(T2 ,T
3 点弧)は、S1 ,S4 をオンさせる。In FIG. 1, when a positive polarity voltage is output to the load 6, if the exciting magnetic pole property of the high frequency transformer 3 is positive (T 1 and T 4 firing), S 1 and S 4 are turned on to turn on the high frequency. When the exciting magnetic pole property of the transformer 3 is negative (T 2 , T 3 ignition)
Turns on S 2 and S 3 . Further, when the negative polarity voltage is output to the load 6, if the exciting magnetic pole property of the high frequency transformer 3 is positive (T 1 , T 4 firing), S 2 and S 3 are turned on, and the exciting magnetic pole property of the high frequency transformer 3 is turned on. Is negative (T 2 , T
(3 ignition) turns on S 1 and S 4 .
【0013】この発明の第1の実施例による図1の動作
を、図2に示す動作波形図,図3に示す論理回路図を参
照しつつ、以下に説明する。負荷6に正弦波の正極性の
電圧を出力する状態では、サイクロコンバータ主回路4
0の半導体スイッチ素子S1 〜S4 は、図2(イ)に示
すようにPWM制御されたオン・オフ動作をし、図3に
示す複数のアンド素子,インバータ素子,オア素子から
構成される論理回路により、半導体スイッチ素子S1 〜
S4 の動作から高周波インバータ40への点弧パルスを
論理演算して、図2(ロ)に示すような高周波インバー
タ主回路20の半導体スイッチ素子T1 〜T4 への点弧
パルスを発生し、図2(ハ)に示すような出力電圧パル
スで高周波トランス3の一次側を励磁することにより、
高周波トランス3は不要な励磁期間が無くなる。The operation of FIG. 1 according to the first embodiment of the present invention will be described below with reference to the operation waveform diagram shown in FIG. 2 and the logic circuit diagram shown in FIG. In the state where the positive voltage of the sine wave is output to the load 6, the cycloconverter main circuit 4
The semiconductor switch elements S 1 to S 4 of 0 perform on / off operation under PWM control as shown in FIG. 2A, and are composed of a plurality of AND elements, inverter elements, and OR elements shown in FIG. Depending on the logic circuit, the semiconductor switch elements S 1 ~
The firing pulse to the high-frequency inverter 40 is logically calculated from the operation of S 4 to generate the firing pulse to the semiconductor switch elements T 1 to T 4 of the high-frequency inverter main circuit 20 as shown in FIG. By exciting the primary side of the high frequency transformer 3 with an output voltage pulse as shown in FIG.
The high frequency transformer 3 has no unnecessary excitation period.
【0014】次に、この発明の第2の実施例による図1
の動作を、図4に示す演算回路図、図5に示す動作説明
図を参照しつつ、以下に説明する。図4に示す演算回路
図において、この直交変換装置の出力電圧の波高値Vo
を得るための波高値指令値Vo* を直流電源1の直流電
圧Edで割ることによりサイクロコンバータ主回路40
の半導体スイッチ素子S1 〜S4 が切り出す電圧パルス
の変調率λmaxを算出し、このλmax値にPWM搬
送波の振幅のピーク値Cp(図5(イ)参照)を掛けて
高周波インバータ主回路20の出力電圧指令レベルEd
* (図5(イ)参照)を算出する。Next, FIG. 1 according to the second embodiment of the present invention.
The operation will be described below with reference to the arithmetic circuit diagram shown in FIG. 4 and the operation explanatory diagram shown in FIG. In the arithmetic circuit diagram shown in FIG. 4, the peak value Vo of the output voltage of this orthogonal transformation device is
To obtain the peak value command value Vo * by the DC voltage Ed of the DC power supply 1 to obtain the cycloconverter main circuit 40.
Of the voltage pulses cut out by the semiconductor switch elements S 1 to S 4 are calculated, and the λmax value is multiplied by the peak value Cp of the amplitude of the PWM carrier wave (see FIG. 5A) to determine the high frequency inverter main circuit 20. Output voltage command level Ed
* (See Fig. 5 (a)) is calculated.
【0015】この出力電圧指令レベルEd* と前記PW
M搬送波とにより比較,論理演算をして高周波インバー
タ主回路20の半導体スイッチ素子T1 〜T4 への点弧
パルスを発生させる。すなわち、前記点弧パルスのパル
ス幅は直流電圧Edが高いときには狭く(図5(ロ)参
照)、直流電圧Edが低いときには広くなり(図5
(ハ)参照)、高周波トランス3の不要な励磁期間が少
なくなる。The output voltage command level Ed * and the PW
Compared by the M carrier to generate firing pulses to the semiconductor switching element T 1 through T 4 of the high-frequency inverter main circuit 20 and the logical operation. That is, the pulse width of the ignition pulse is narrow when the DC voltage Ed is high (see FIG. 5B), and wide when the DC voltage Ed is low (FIG. 5).
(See (c)), the unnecessary excitation period of the high frequency transformer 3 is reduced.
【0016】図5に示した動作説明図において、PWM
搬送波の振幅のピーク値Cpと、出力電圧指令レベルE
d* と、波高値指令レベルVo* とには、常に、式
(2)に示す関係が成立する必要がある。In the operation explanatory view shown in FIG. 5, PWM
The peak value Cp of the carrier wave amplitude and the output voltage command level E
The relationship shown in Expression (2) must always be established between d * and the peak value command level Vo * .
【0017】[0017]
【数2】 |Cp|≧|Ed* |≧|Vo* | …(2) 以上に記載したこの発明の第1,第2の実施例において
は、単相出力の直交変換装置について説明したが、多
相、例えば三相出力の直交変換装置であっても、この発
明の直交変換装置の制御方法は適用できる。## EQU00002 ## | Cp | .gtoreq. | Ed * | .gtoreq. | Vo * | (2) In the first and second embodiments of the present invention described above, the single-phase output orthogonal transform device has been described. The control method of the orthogonal transform device of the present invention can be applied to a multi-phase, for example, a three-phase output orthogonal transform device.
【0018】[0018]
【発明の効果】この発明の直交変換装置の制御方法によ
れば、燃料電池,太陽電池などのように電圧変動の大き
い直流電源をこの直交変換装置に用いたときにも、高周
波トランスの飽和磁束密度を従来の制御方法に比して少
なく設計でき、高周波トランスが小形化し、装置も小
形,低コストになる効果をもたらす。According to the control method of the orthogonal transformation device of the present invention, even when a DC power source such as a fuel cell or a solar cell having a large voltage fluctuation is used in the orthogonal transformation device, the saturation magnetic flux of the high frequency transformer is increased. The density can be designed to be smaller than that of the conventional control method, the high frequency transformer can be downsized, the device can be downsized, and the cost can be reduced.
【図1】この発明の実施例を示す直交変換装置の主回路
構成図FIG. 1 is a main circuit configuration diagram of an orthogonal transform device showing an embodiment of the present invention.
【図2】この発明の第1の実施例の動作説明図FIG. 2 is an operation explanatory diagram of the first embodiment of the present invention.
【図3】この発明の第1の実施例を示す論理回路構成図FIG. 3 is a logic circuit configuration diagram showing a first embodiment of the present invention.
【図4】この発明の第2の実施例を示す演算回路構成図FIG. 4 is a configuration diagram of an arithmetic circuit showing a second embodiment of the present invention.
【図5】この発明の第2の実施例の動作説明図FIG. 5 is an operation explanatory diagram of the second embodiment of the present invention.
【図6】従来例を示す直交変換装置の構成図FIG. 6 is a block diagram of an orthogonal transform device showing a conventional example.
【図7】図6の動作説明図7 is an explanatory diagram of the operation of FIG.
1…直流電源、2…高周波インバータ、3…高周波トラ
ンス、4…サイクロコンバータ、5…フィルタ、6…負
荷、20…高周波インバータ主回路、40…サイクロコ
ンバータ主回路。DESCRIPTION OF SYMBOLS 1 ... DC power supply, 2 ... High frequency inverter, 3 ... High frequency transformer, 4 ... Cyclo converter, 5 ... Filter, 6 ... Load, 20 ... High frequency inverter main circuit, 40 ... Cyclo converter main circuit.
Claims (2)
周波インバータと、該高周波インバータの出力に接続さ
れる高周波トランスと、該高周波トランスの二次側に接
続されるサイクロコンバータと、該サイクロコンバータ
の出力に接続されるフィルタとから構成される直交変換
装置の制御方法において、 PWM制御された前記サイクロコンバータの出力電圧パ
ルスのパルス幅に、前記高周波インバータの正,負極性
で発生する出力電圧パルスのパルス幅をそれぞれ追従さ
せることを特徴とする直交変換装置の制御方法。1. A high frequency inverter for converting a DC voltage into a high frequency AC voltage, a high frequency transformer connected to the output of the high frequency inverter, a cycloconverter connected to the secondary side of the high frequency transformer, and the cycloconverter. And a filter connected to the output of the high-frequency inverter, wherein the output voltage pulse generated by the high frequency inverter is positive or negative in the pulse width of the PWM-controlled output voltage pulse of the cycloconverter. A method for controlling an orthogonal transformation device, characterized in that each of the pulse widths is tracked.
周波インバータと、該高周波インバータの出力に接続さ
れる高周波トランスと、該高周波トランスの二次側に接
続されるサイクロコンバータと、該サイクロコンバータ
の出力に接続されるフィルタとから構成される直交変換
装置の制御方法において、 前記高周波インバータの正,負極性で発生する出力電圧
パルスのパルス幅を、前記直流電圧の変化に反比例させ
ることを特徴とする直交変換装置の制御方法。2. A high frequency inverter for converting a DC voltage into a high frequency AC voltage, a high frequency transformer connected to the output of the high frequency inverter, a cycloconverter connected to the secondary side of the high frequency transformer, and the cycloconverter. And a filter connected to the output of the high frequency inverter, wherein the pulse width of the output voltage pulse generated in the positive or negative polarity of the high frequency inverter is inversely proportional to the change of the DC voltage. And a method for controlling an orthogonal transform device.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP6305771A JPH08168266A (en) | 1994-12-09 | 1994-12-09 | Method for controlling dc-ac converter |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP6305771A JPH08168266A (en) | 1994-12-09 | 1994-12-09 | Method for controlling dc-ac converter |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH08168266A true JPH08168266A (en) | 1996-06-25 |
Family
ID=17949153
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP6305771A Pending JPH08168266A (en) | 1994-12-09 | 1994-12-09 | Method for controlling dc-ac converter |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH08168266A (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006246673A (en) * | 2005-03-07 | 2006-09-14 | Nagaoka Univ Of Technology | Control unit for isolated direct power conversion device |
WO2015038995A1 (en) * | 2013-09-16 | 2015-03-19 | Enphase Energy, Inc. | Single-phase cycloconverter with integrated line-cycle energy storage |
JP2016067123A (en) * | 2014-09-25 | 2016-04-28 | 株式会社豊田中央研究所 | Power converter |
US9479082B2 (en) | 2011-01-04 | 2016-10-25 | Enphase Energy, Inc. | Method and apparatus for resonant power conversion |
-
1994
- 1994-12-09 JP JP6305771A patent/JPH08168266A/en active Pending
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006246673A (en) * | 2005-03-07 | 2006-09-14 | Nagaoka Univ Of Technology | Control unit for isolated direct power conversion device |
US9479082B2 (en) | 2011-01-04 | 2016-10-25 | Enphase Energy, Inc. | Method and apparatus for resonant power conversion |
US10141868B2 (en) | 2011-01-04 | 2018-11-27 | Enphase Energy, Inc. | Method and apparatus for resonant power conversion |
WO2015038995A1 (en) * | 2013-09-16 | 2015-03-19 | Enphase Energy, Inc. | Single-phase cycloconverter with integrated line-cycle energy storage |
JP2016530872A (en) * | 2013-09-16 | 2016-09-29 | エンフェーズ エナジー インコーポレイテッドEnphase Energy, Inc. | Single-phase cycloconverter with integrated line cycle energy storage |
US9531300B2 (en) | 2013-09-16 | 2016-12-27 | Enphase Energy, Inc. | Single phase cycloconverter with integrated line-cycle energy storage |
JP2016067123A (en) * | 2014-09-25 | 2016-04-28 | 株式会社豊田中央研究所 | Power converter |
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