JPS6339464A - Series resonance converter - Google Patents
Series resonance converterInfo
- Publication number
- JPS6339464A JPS6339464A JP61181771A JP18177186A JPS6339464A JP S6339464 A JPS6339464 A JP S6339464A JP 61181771 A JP61181771 A JP 61181771A JP 18177186 A JP18177186 A JP 18177186A JP S6339464 A JPS6339464 A JP S6339464A
- Authority
- JP
- Japan
- Prior art keywords
- series
- resonant
- series resonant
- resonance
- frequency
- 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
- 239000003990 capacitor Substances 0.000 abstract description 19
- 239000004065 semiconductor Substances 0.000 description 13
- 238000010586 diagram Methods 0.000 description 6
- 230000007423 decrease Effects 0.000 description 4
- 238000013459 approach Methods 0.000 description 1
- 238000011002 quantification Methods 0.000 description 1
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
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
Landscapes
- Dc-Dc Converters (AREA)
Abstract
Description
【発明の詳細な説明】
「産業上の利用分野」
この発明は直流電圧を負荷に必要な直流電圧に変換する
直列共振コンバータに関するものでル）る。DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a series resonant converter that converts a DC voltage to a DC voltage required for a load.
「従来の技術」
直流電圧を異なった極性あるいは異′なった市川値に変
換する場合に直列共振コンバータが使用きれている。直
列共振コンバー タは、インダクタ及びキャパシタの直
列共１辰回路と、バイポーラトランジスタ、Ｍ ＯＳ
＋−ランジスタ等の半導体スイッチと、ダイオードによ
り構成され、半導体スイッチを交互にオン、オンさせる
ことにより共振電流を流し、その共振電流を整流、）１
′−滑して再び直流電圧を得るコンバータである。``Prior Art'' Series resonant converters have been used to convert DC voltages to different polarities or different Ichikawa values. A series resonant converter consists of a series circuit of an inductor and a capacitor, a bipolar transistor, and a MOS
It consists of semiconductor switches such as +- transistors and diodes, and by alternately turning the semiconductor switches on and on, a resonant current flows, and the resonant current is rectified.)1
' - is a converter that slips and obtains DC voltage again.
共振電流は一般に正弦波状の波形となり、一定時間経過
後、自然に零となるため、半導体スイッチを強制的にオ
ンさせろ必要がなく、またスイッチ素子のターンオン時
に流れる電流もゆるやかに増加することからスイッチン
グ損失は原理的に存在せず、高効率化、低雑音化及び小
形、Φγ量化の効果が期待できろ。Resonant current generally has a sinusoidal waveform and naturally becomes zero after a certain period of time, so there is no need to forcibly turn on the semiconductor switch, and the current that flows when the switch element is turned on also increases gradually, so switching There is no loss in principle, and the effects of higher efficiency, lower noise, smaller size, and Φγ quantification can be expected.
第４図は従来の直列共振コンバータを示す（例えぼ、Ｔ
（、、、’ｊ ＩぐＩＮＧ ： Ｍｏｄｅｌｉｎｇ Ｔ
ｈｅ Ｆｕｌｌ −ＢｒｉｄｇｅＳｃｒｉ〔１ｓ−Ｒｅ
ｓｏｎａｎｔ ’Ｐｏｗｅｒ Ｃｏｎｖｅｒｔｅｒ、
ＨＥＥＥＴｒａｎｓ ｏｎＡＥ、 ＡＥＳ−１８，茄
４ ＪＵｌｒ、Ｙ １９８２ ）。Figure 4 shows a conventional series resonant converter (for example, T
（、、、'j IGUING: Modeling T
he Full-BridgeScri[1s-Re
sonant'Power Converter,
HEEE Trans on AE, AES-18, 4 JUlr, Y 1982).
第４図において、スイッチ素子としてのトランジスタよ
りなる半導体スイッチ１．１．．１４を同時にオンする
と、直流電源２３より半導体スイッチ１１−整流回路２
４−負荷３０（これと並列のキャパシタ２９）−整流回
路２４−キャンくシタ２１−インダクタ２２−半導体ス
イッチ１４の第１の共振ループ１１に直列共振電流が流
れる。インダクタ２２のインダクタンスをＬｏ 、
キャンくシタ２１のキャパシタンスをＣＯ，キャパシタ
２９のキャンくシタンスをＣ１とすると、Ｃｔ：））Ｃ
ｏとされているから前記直列共振電流は流れはじめてか
らπｙ’Ｔｒｏｃｏ時間後に零となり、その時のキャパ
シタ２］は直流電源と逆極性で２倍の大きさの電圧値に
充電される。In FIG. 4, a semiconductor switch 1.1 consisting of a transistor as a switching element is shown. ．． 14 at the same time, the DC power supply 23 connects the semiconductor switch 11 to the rectifier circuit 2.
A series resonant current flows through the first resonant loop 11 of 4-load 30 (capacitor 29 in parallel with this)-rectifier circuit 24-canceller 21-inductor 22-semiconductor switch 14. The inductance of the inductor 22 is Lo,
If the capacitance of the capacitor 21 is CO and the capacitance of the capacitor 29 is C1, then Ct:))C
0, the series resonance current becomes zero after πy'Troco time after it starts flowing, and the capacitor 2 at that time is charged to a voltage value twice as large as that of the DC power supply with the opposite polarity.
このため今度は、第１の共振ループ１１に含まれ、半導
体スイッチ１１．１４とそれぞれ並列ダイオード１５．
１８が導通し、前記直列共振電流とは逆方向の直列共振
電流が流れる。この電流もインダクタ２２とキャパシタ
２１の共振電流となるから、π７７時間後に零となり、
その時のキャパシタ２１は直流電源と逆極性で負荷電圧
の２倍まで減少し、動作の半周期は終了する。For this purpose, the first resonant loop 11 includes a semiconductor switch 11.14 and a parallel diode 15.14, respectively.
18 becomes conductive, and a series resonance current flows in the opposite direction to the series resonance current. This current also becomes a resonant current of the inductor 22 and capacitor 21, so it becomes zero after π77 hours.
At that time, the capacitor 21 has a polarity opposite to that of the DC power supply, and the voltage decreases to twice the load voltage, and a half cycle of operation is completed.
次に半導体スイッチ１３．１２を同時にオンさせること
により、直流電源２３より半嗜体スイッチ］３−インダ
クタ２２−キャパシタ２ ］ −整流回路２４−負荷３
０（キャパシタ２９）−整流回路２４−半導体スイッチ
１２の第２の共振ル−プ１２に直列共振電流が流れる同
様のモードが生じ、この半周期は終了する。Next, by turning on the semiconductor switches 13 and 12 at the same time, the DC power supply 23 is connected to the semi-isolated switch ] 3 - inductor 22 - capacitor 2 ] - rectifier circuit 24 - load 3
A similar mode occurs in which a series resonant current flows in the second resonant loop 12 of 0 (capacitor 29)-rectifier circuit 24-semiconductor switch 12, and this half cycle ends.
第４図の従来の直列共振コンバータにおいて、整流回路
２４を通して負荷３０側へ伝達される電流は、半導体ス
イッチ素子をオン・オフさせる周波数ｆとキャパシタ２
１のキャンくシタンスＣＯに比例するため、負荷３０の
抵抗値をＲ１とすて）と負荷電圧は、ｉ’、Ｃｏ、Ｒに
比例することとプエろ。In the conventional series resonant converter shown in FIG. 4, the current transmitted to the load 30 side through the rectifier circuit 24 has a frequency f for turning on and off the semiconductor switching element and a capacitor 2.
Since the resistance value of the load 30 is assumed to be R1, the load voltage is proportional to i', Co, and R.
従って、負荷抵抗値１（・が変化する場合に、負荷電圧
を一定に保持するための制御は、［またはＣ（）のいず
れかを制御することにより可能となるが、ＣＯを連続的
に制御することは現在のところ困難である。従って一般
に負荷が変動した場合でも負荷電圧を一定値に保持する
ためには動作周波数ｆを制御することにより行っている
。Therefore, control to keep the load voltage constant when the load resistance value 1() changes is possible by controlling either [or C(), but CO is continuously controlled It is currently difficult to do so.Therefore, in order to maintain the load voltage at a constant value even when the load fluctuates, it is generally done by controlling the operating frequency f.
従って負荷抵抗値Ｒの値が増加した場合には動ｒ［周波
数〔を比例して減少させるが、軽負荷時には動作周波数
ｆが可聴周波数となり、騒音が発生するという問題があ
った。Therefore, when the value of the load resistance value R increases, the dynamic r[frequency] decreases proportionally, but when the load is light, the operating frequency f becomes an audible frequency, causing a problem that noise is generated.
この発明の目的は無負荷から全負荷まで定電圧制御を行
う場合、動作周波数の変化範囲を少なくするとともに最
低動作周波数をクランプできる直列共振コンバータを提
供することにある。An object of the present invention is to provide a series resonant converter that can reduce the operating frequency change range and clamp the lowest operating frequency when performing constant voltage control from no load to full load.
１問題点を解決するための手段」
この発明では上記の問題を解決するため、第１スイッチ
素子及び第２スイッチ素子を有する第１直列共振ループ
と、第３スイッチ素子及び第４スイッチ素子を有する第
２直列共振ル−プと、これら第１直列共振ループ及び第
２直列共振ル−プに共通に挿入された整流回路と、上記
第１、第２スイッチ素子の制御により上記第１直列共振
ループに電流を流し、上記第３、第４スイッチ素子の制
御により上記第２直列共振ループに電流を流す直流電源
手段と、上記第１直列共振ループ、上記第２直列共振ル
ープに挿入され、これら第１、第２直列共振ループの直
列共振周波数よりも十分低い可聴周波数以上の共振周波
数をもつ並列共振手段とを具備している。In order to solve the above problem, the present invention has a first series resonant loop having a first switch element and a second switch element, and a third switch element and a fourth switch element. A second series resonant loop, a rectifier circuit inserted in common to the first series resonant loop and the second series resonant loop, and the first series resonant loop controlled by the first and second switch elements. DC power supply means for passing current through the second series resonant loop under the control of the third and fourth switch elements; 1. Parallel resonant means having a resonant frequency equal to or higher than an audible frequency that is sufficiently lower than the series resonant frequency of the second series resonant loop.
従来は定電圧制御を行う場合軽負荷時には動作周波数を
低くして負荷電流の増加をおさえる必要があり、このた
め動作周波数が可聴周波数帯に入り、騒音を発生すると
いう問題があったが、どの発明では軽負荷時において動
作周波数が可聴周波数帯に入る前記並列共振手段が共振
し、そのインピーダンスが著しく大きくなって負荷電流
がおさえられ、無騒音化が達成できる。Conventionally, when performing constant voltage control, it was necessary to lower the operating frequency at light loads to suppress the increase in load current, which caused the problem that the operating frequency fell into the audible frequency band and generated noise. In the present invention, when the load is light, the parallel resonance means whose operating frequency falls within the audible frequency band resonates, and its impedance becomes significantly large, so that the load current is suppressed and noiseless operation can be achieved.
「実施例」 第１図はこの発明の第１の実施例を示す回路図である。"Example" FIG. 1 is a circuit diagram showing a first embodiment of the invention.
この例において並列共振手段３］がキャパシタ３２．イ
ンダクタ３３とで構成され、この並列共振手段３］は、
整流回路２４、キャパシタ２１、インダクタ２２と直列
に接続されて、第１直列共振ループ１１と第２直列共振
ループ１２とに共通に設けられた場合である。その他第
４図と同一符号は同一部分を示す。In this example, the parallel resonant means 3] is a capacitor 32. and an inductor 33, this parallel resonant means 3]
This is a case where it is connected in series with the rectifier circuit 24, the capacitor 21, and the inductor 22, and is provided in common to the first series resonance loop 11 and the second series resonance loop 12. Otherwise, the same reference numerals as in FIG. 4 indicate the same parts.
並列共振手段３］のキャパシタ３２のキャパシタンスな
Ｃｍ 、 インダクタ３３のインダクタンスをＬＴｎ
とすれば、並列共振手段３１の共振周波数ｆ２＝％／π
／ｖ１闇τを、キャパシタ２１．インダクタ２２で構成
される直列共振回路の共振周波数、ｆｏ＝％／π１５よ
り低く設定し、ｆ２をコンバータの最低動作周波数とし
、このｆ２は可聴周波数より高くする。並列共振手段３
１のインピーダンスは、動作周波数が共振周波数ｆ２の
点で最大となり動作周波数が「２より高くなると急減す
る。The capacitance of the capacitor 32 of the parallel resonance means 3 is Cm, and the inductance of the inductor 33 is LTn.
Then, the resonant frequency f2 of the parallel resonant means 31=%/π
/v1 darkness τ, capacitor 21. The resonant frequency of the series resonant circuit constituted by the inductor 22 is set lower than fo=%/π15, and f2 is the lowest operating frequency of the converter, and this f2 is set higher than the audible frequency. Parallel resonance means 3
The impedance of 1 reaches its maximum at the point where the operating frequency is the resonant frequency f2, and rapidly decreases when the operating frequency becomes higher than 2.
令弟１図において半導体スイッチ１．１．７４を同時オ
ンすると従来の直列共振コンバータ（第４図）と同様に
第１の共振ルー プ１１により、直列共振電流が流れる
が、この実施例では１１の中に並列共振手段３１が含ま
れるため、直列共振電流の犬きさが動作周波数により大
きく変化できる。すなわち、動作周波数が並列共振手段
３］の共振周波数より充分に高い場合には並列共振手段
３］のインピーダンスが充分に低いため、直列共振電流
の大きさは第４図に示した従来回路のそれとほぼ同等と
なる。しかし、動作周波数が並列共振手段３１の共振周
波数に近づくと並列共振手段３］のインピーダンスが急
増するため、直列共振電流の大きさは急減する。When the semiconductor switches 1, 1, and 74 are simultaneously turned on in Figure 1, a series resonant current flows through the first resonance loop 11, similar to the conventional series resonant converter (Figure 4). Since the parallel resonant means 31 is included in the parallel resonant means 31, the magnitude of the series resonant current can vary greatly depending on the operating frequency. In other words, when the operating frequency is sufficiently higher than the resonant frequency of the parallel resonant means 3], the impedance of the parallel resonant means 3 is sufficiently low, so the magnitude of the series resonant current is equal to that of the conventional circuit shown in Fig. 4. Almost equivalent. However, as the operating frequency approaches the resonant frequency of the parallel resonant means 31, the impedance of the parallel resonant means 3 increases rapidly, and the magnitude of the series resonant current rapidly decreases.
次に半導体スイッチ１３．１２を同時にオンさせること
により第２の共振ループ１２に直列共振電流が流れ、こ
の電流も上記ｌ］により流れる直列共振電流と同様に動
作周波数により大きく変化する。Next, by simultaneously turning on the semiconductor switches 13 and 12, a series resonant current flows through the second resonant loop 12, and this current also varies greatly depending on the operating frequency, similar to the series resonant current flowing due to 1] above.
従って１２付近においては動作周波数をわずかに変える
ことにより、直列共振電流を大幅に変化させることが可
能となり、出力電圧をＮ制御することができる。Therefore, by slightly changing the operating frequency near 12, it is possible to significantly change the series resonance current, and the output voltage can be controlled by N.
第２図はこの発明の第２の実施例を示す回路図で、直流
入力と直流出力とを直流的に絶縁するためにトランス３
４を使った直列共振コンバータにこの発明を適用したも
のである。ずなわちトランス３４の一次側が並列共振手
段３１．キャパシタ２１、インダクタ２２と直列に接続
され、トランス３４の二次側は整流回路２４の交流側入
力端子と接続される。この第２の実施例による動作は第
１図に示した第１の実施例による動作と同一であるため
説明は省略する。この第２の実施例によれば入力側と出
力側とを直流的に絶縁でき、かつトランス３４の巻数ｎ
＋／ｎ２により出力電圧を自由に設定できる。FIG. 2 is a circuit diagram showing a second embodiment of the present invention, in which a transformer is used to isolate DC input and DC output.
This invention is applied to a series resonant converter using 4. That is, the primary side of the transformer 34 is the parallel resonant means 31. The transformer 34 is connected in series with the capacitor 21 and the inductor 22, and the secondary side of the transformer 34 is connected to the AC side input terminal of the rectifier circuit 24. The operation of this second embodiment is the same as the operation of the first embodiment shown in FIG. 1, so a description thereof will be omitted. According to this second embodiment, the input side and the output side can be isolated in terms of direct current, and the number of turns of the transformer 34 is n.
+/n2 allows the output voltage to be freely set.
第３図はこの発明の第３の実施例を示し、並列共振手段
４１．４２を各直列共振ループ１１．ｈにそれぞれ各別
に挿入した場合である。FIG. 3 shows a third embodiment of the invention, in which parallel resonant means 41, 42 are connected to each series resonant loop 11. This is a case where each is inserted separately into h.
「発明の効果」
以」二説明したようにこの発明は並列共振手段を整流回
路の交流側端子と直列に接続したので、負荷電流の変化
に対して動作周波数の変化範囲を狭くすることができ、
直列共振コンバータを可聴領域以」二の周波数で動作さ
せることが可能となり、無騒音の直列共振コンバータが
実現できる利点がある。``Effects of the Invention'' As explained hereinafter, in this invention, the parallel resonant means is connected in series with the AC side terminal of the rectifier circuit, so the range of change in operating frequency can be narrowed in response to changes in load current. ,
It becomes possible to operate the series resonant converter at a frequency below the audible range, and there is an advantage that a noiseless series resonant converter can be realized.
第１図はこの発明の第１の実施例を示す回路図、第２図
はこの発明の第２の実施例を示す回路１２１、第３図は
この発明の第３の実施例を示す回路図、第４図は従来の
直列共振コンバークを示す回路図である。
１１．１２，１３．１／Ｉ：半導体スイッチ、１５．１
６，１７，１８，２５．２Ｊ ２７゜２８：ダイオー
ド、２３：直流電源、２２．３３＝インダクタ、２１，
２９，３２：キャパシタ、２４：整流回路、３０：負荷
、３１，４１．／１２＝並列共振手段、１１：第１の共
振ルー プ、ｅ２：第２の共振ループ、３４ ： ｌ−
ランス。FIG. 1 is a circuit diagram showing a first embodiment of this invention, FIG. 2 is a circuit diagram 121 showing a second embodiment of this invention, and FIG. 3 is a circuit diagram showing a third embodiment of this invention. , FIG. 4 is a circuit diagram showing a conventional series resonant converter. 11.12, 13.1/I: Semiconductor switch, 15.1
6, 17, 18, 25.2J 27° 28: Diode, 23: DC power supply, 22.33 = Inductor, 21,
29, 32: Capacitor, 24: Rectifier circuit, 30: Load, 31, 41. /12=parallel resonant means, 11: first resonant loop, e2: second resonant loop, 34: l-
Lance.
Claims (1)
第１直列共振ループと、 第３スイッチ素子及び第４スイッチ素子を有する第２直
列共振ループと、 これら第１直列共振ループ及び第２直列共振ループに共
通に挿入された整流回路と、 上記第１、第２スイッチ素子の制御により上記第１直列
共振ループに電流を流し、上記第３、第４スイッチ素子
の制御により上記第２直列共振ループに電流を流す直流
電源手段と、 上記第１直列共振ループ、上記第２直列共振ループに挿
入され、これら第１、第２直列共振ループの直列共振周
波数よりも十分低い可聴周波数以上の共振周波数をもつ
並列共振手段とを具備する直列共振コンバータ。(1) A first series resonant loop having a first switch element and a second switch element; a second series resonant loop having a third switch element and a fourth switch element; these first series resonant loops and second series resonance loops; A rectifier circuit commonly inserted into the loop, and a current flowing through the first series resonant loop by controlling the first and second switch elements, and a current flowing through the second series resonant loop by controlling the third and fourth switch elements. a direct current power supply means that is inserted into the first series resonant loop and the second series resonant loop, and has a resonant frequency equal to or higher than an audible frequency that is sufficiently lower than the series resonant frequencies of the first and second series resonant loops; A series resonant converter comprising parallel resonant means.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61181771A JPH0740787B2 (en) | 1986-08-01 | 1986-08-01 | Series resonance converter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61181771A JPH0740787B2 (en) | 1986-08-01 | 1986-08-01 | Series resonance converter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6339464A true JPS6339464A (en) | 1988-02-19 |
| JPH0740787B2 JPH0740787B2 (en) | 1995-05-01 |
Family
ID=16106597
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61181771A Expired - Fee Related JPH0740787B2 (en) | 1986-08-01 | 1986-08-01 | Series resonance converter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0740787B2 (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58123369A (en) * | 1982-01-14 | 1983-07-22 | Matsushita Electric Ind Co Ltd | Constant-voltage power source |
-
1986
- 1986-08-01 JP JP61181771A patent/JPH0740787B2/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58123369A (en) * | 1982-01-14 | 1983-07-22 | Matsushita Electric Ind Co Ltd | Constant-voltage power source |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0740787B2 (en) | 1995-05-01 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |