JPH0753390Y2 - Uninterruptible power system - Google Patents
Uninterruptible power systemInfo
- Publication number
- JPH0753390Y2 JPH0753390Y2 JP1987028026U JP2802687U JPH0753390Y2 JP H0753390 Y2 JPH0753390 Y2 JP H0753390Y2 JP 1987028026 U JP1987028026 U JP 1987028026U JP 2802687 U JP2802687 U JP 2802687U JP H0753390 Y2 JPH0753390 Y2 JP H0753390Y2
- Authority
- JP
- Japan
- Prior art keywords
- power
- output
- inverter
- time
- load
- 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 - Lifetime
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- Stand-By Power Supply Arrangements (AREA)
Description
【考案の詳細な説明】 「産業上の利用分野」 この考案は商用電力受電中はその商用電力を負荷へ供給
し、停電時は内蔵の蓄電池電力をインバータにより交流
に変換して負荷へ供給し、特にこの切替えを、商用電力
と変換交流電力とを同期した状態で行う無停電電源装置
に関する。[Detailed description of the device] "Industrial application field" This device supplies the commercial power to the load while receiving the commercial power, and converts the built-in battery power to AC by an inverter and supplies it to the load during a power failure. In particular, the present invention relates to an uninterruptible power supply device that performs this switching in a state where commercial power and converted AC power are synchronized.
「従来の技術」 従来の小形の無停電電源装置は第４図に示すように、商
用電源11からの商用電力は入力端子12を通じて交流スイ
ッチ13へ供給されると共に充電器14へ供給される。交流
スイッチ13の出力は出力端子15を通じて負荷16へ供給さ
れる。充電器14の出力により内蔵の蓄電池17が充電さ
れ、停電時に蓄電池17の直流出力はインバータ18により
交流に変換されて出力端子15を通じて負荷16へ供給され
る。"Prior Art" In a conventional small uninterruptible power supply, commercial power from a commercial power supply 11 is supplied to an AC switch 13 through an input terminal 12 and a charger 14 as shown in FIG. The output of the AC switch 13 is supplied to the load 16 through the output terminal 15. The built-in storage battery 17 is charged by the output of the charger 14, and the DC output of the storage battery 17 is converted into AC by the inverter 18 and supplied to the load 16 through the output terminal 15 at the time of power failure.
小形無停電電源装置では回路構成の簡易な事から、商用
切替回路に自己消弧形のトライアック等を交流スイッチ
13として利用してきた。しかし、トライアックの消弧を
完全に行う為には第５図Ａに示すように無電圧期間を設
ける必要があり出力波形の一部に欠損が生じる。第６図
Ａに示す抵抗負荷の場合は、出力電圧、出力電流はそれ
ぞれ第５図A,Bに示すように問題はなく、また第６図Ｂ
に示すように直接整流を行うスイッチングレギュレータ
負荷では出力電流は第５図Ｃに示すようになり、なんの
問題もなく、運転が可能であるが、第６図Ｃに示すトラ
ンス入力のコイル入力負荷では磁気回路の正負サイクル
の非対称による直流偏磁を招き、第５図Ｄに示すように
切替時に突入電流を発生し、インバータ出力の低下の原
因となっていた。Because of the simple circuit configuration of the small uninterruptible power supply, a self-extinguishing triac etc. is used as an AC switch in the commercial switching circuit.
I have used it as 13. However, in order to completely extinguish the arc of the triac, it is necessary to provide a no-voltage period as shown in FIG. 5A, and a part of the output waveform is lost. In the case of the resistive load shown in FIG. 6A, the output voltage and the output current have no problem as shown in FIGS. 5A and 5B, respectively.
In the switching regulator load that performs direct rectification as shown in Fig. 5, the output current is as shown in Fig. 5C, and operation is possible without any problems. However, the coil input load of the transformer input shown in Fig. 6C is available. In this case, asymmetrical positive and negative cycles of the magnetic circuit lead to DC bias magnetization, which causes an inrush current at the time of switching as shown in FIG. 5D, which causes a reduction in the inverter output.
この考案の目的は、商用電源出力とインバータ出力との
切替時に、波形歪によって生ずる負荷機器の直流偏磁突
入電流を抑制して、切替時の出力電圧垂下を防止した無
停電電源装置を提供することにある。An object of the present invention is to provide an uninterruptible power supply device which suppresses an output voltage droop at the time of switching, by suppressing a DC inrush current of a load device caused by waveform distortion at the time of switching between a commercial power supply output and an inverter output. Especially.
「問題点を解決するための手段」 この考案によれば商用電力受電中はその商用電力を、自
然消弧形半導体スイッチを通じて負荷へ供給し、その商
用電力に同期した基準発振信号を得、停電検出器により
停電を検出すると、その検出出力により半導体スイッチ
に対するオン駆動を停止し、かつ内蔵蓄電池電力を、イ
ンバータにより上記基準発振信号を基準として交流電力
に変換し、その変換された交流電力を負荷へ、商用電力
と切替えて供給する無停電電源装置において、 停電検出器の検出出力を少なくとも半導体スイッチの自
然消弧時間遅延させて、インバータよりの交流電力の供
給を遅らせて供給電力欠損時間を設ける手段と、インバ
ータへ基準として供給する基準発振信号を、供給電力欠
損時間とほぼ対応した時間だけ遅延させる移相手段とが
設けられる。[Means for Solving Problems] According to the present invention, while commercial power is being received, the commercial power is supplied to a load through a natural arc-extinguishing semiconductor switch, a reference oscillation signal synchronized with the commercial power is obtained, and a power failure occurs. When the detector detects a power failure, the detection output stops the on-driving of the semiconductor switch, and the built-in storage battery power is converted into AC power by the inverter with the reference oscillation signal as the reference, and the converted AC power is loaded. In an uninterruptible power supply that switches to and supplies commercial power, the detection output of the power failure detector is delayed by at least the natural extinction time of the semiconductor switch, and the supply of AC power from the inverter is delayed to provide a power failure time. Means and a phase shift for delaying the reference oscillation signal supplied as a reference to the inverter by a time substantially corresponding to the power supply loss time. And the stage is provided.
前述した負荷の直流偏磁突入電流は、出力切替え時の波
形欠損部分のため、切替え時の極性半サイクルでの電圧
時間積が不足することにより、次半サイクルで鉄心飽和
を招くことから発生する。しかし上述したこの考案では
波形欠損相当時間インバータ基準波形が遅らせるため
に、切替え時の半サイクルのみその期間が通常の半サイ
クル周期より長い波形が発生し、切替え側半サイクルの
電圧時間積が大となり、次半サイクルの電圧時間積とほ
ぼ等しくなり、切替え時の次半サイクルで鉄心飽和を招
くことがなく、突入電流も発生しない。The DC inrush current of the load described above occurs because the voltage-time product in the polarity half cycle at the time of switching is insufficient due to the waveform loss part at the time of switching the output, which causes iron core saturation in the next half cycle. . However, in this invention described above, the waveform corresponding to the waveform loss is delayed because the inverter reference waveform is delayed, so that only a half cycle at the time of switching generates a waveform whose period is longer than the normal half cycle period, and the voltage-time product of the switching side half cycle becomes large. , Which is almost equal to the voltage-time product of the next half cycle, the core saturation does not occur in the next half cycle at the time of switching, and no inrush current occurs.
「実施例」 第１図はこの考案の実施例を示し、第４図と対応する部
分には同一符号を付けてあるが、第４図よりは具体的に
示してある。入力端子12a,12b間に商用電源11が接続さ
れている。入力端子12aと出力端子15a間にトライアック
などの自己消弧形半導体スイッチよりなる交流スイッチ
13が接続され、端子12b,15b間は配線19が接続され、出
力端子15a,15b間に負荷16が接続される。インバータ18
はトランジスタQ1〜Q4をブリッジ接続し、その一対の入
力点間に蓄電池17が出力され、一対の出力点間は、正弦
波に波形整形するための濾波器21を通じて出力端子15a,
15b間に接続される。入力端子12a,12bより商用電圧VIN
が検出制御部22に入力され、その商用電圧VINの大きさ
により停電を検出し、またその商用電圧と同期した基準
発振信号を作り、その出力に応じてトランジスタQ1〜Q4
をスイッチ制御して蓄電池17の直流出力を交流電力に変
換して出力端子15a,15bへ供給する。[Embodiment] FIG. 1 shows an embodiment of the present invention, in which parts corresponding to those in FIG. 4 are designated by the same reference numerals, but are shown more concretely than in FIG. The commercial power supply 11 is connected between the input terminals 12a and 12b. AC switch consisting of self-extinguishing type semiconductor switch such as triac between input terminal 12a and output terminal 15a
13 is connected, a wire 19 is connected between the terminals 12b and 15b, and a load 16 is connected between the output terminals 15a and 15b. Inverter 18
The transistor Q 1 to Q 4 bridge-connected storage battery 17 is outputted between the pair of input points, the pair of output point, the output terminal 15a through the filter 21 for waveform shaping the sine wave,
Connected between 15b. Commercial voltage V IN from input terminals 12a and 12b
Is input to the detection control unit 22, a power failure is detected by the magnitude of the commercial voltage V IN , a reference oscillation signal synchronized with the commercial voltage is generated, and the transistors Q 1 to Q 4 are output according to the output.
Is controlled to convert the DC output of the storage battery 17 into AC power and supply it to the output terminals 15a and 15b.
商用電力受電中は商用電源11の電力は入力端子12a,12
b、自然消弧形半導体の交流スイッチ13、出力端子15a,1
5bを経て負荷16へ直送されている。同時に充電器14は蓄
電池17を充電し、満充電状態に保ち、インバータ18は、
検出制御部22内の基準発振回路を商用電力に同期させた
状態で停電に備える。停電時には検出制御部22内の停電
検出器が、停電検出と同時に交流スイッチ13の遮断信号
と、インバータ制御回路の起動信号を発生して、交流ス
イッチ13の遮断と、インバータ18の起動とを行い、蓄電
池17の電力を交流変換して負荷16へ即時給電を行う。While the commercial power is being received, the power of the commercial power supply 11 is input to the input terminals 12a, 12
b, natural arc extinguishing type semiconductor AC switch 13, output terminals 15a, 1
It is sent directly to the load 16 via 5b. At the same time, the charger 14 charges the storage battery 17 and keeps it fully charged, and the inverter 18
The reference oscillation circuit in the detection control unit 22 is prepared for a power failure while being synchronized with commercial power. At the time of a power failure, the power failure detector in the detection control unit 22 generates a cutoff signal for the AC switch 13 and a start signal for the inverter control circuit simultaneously with the detection of the power failure, shuts off the AC switch 13 and starts the inverter 18. , AC power of the storage battery 17 is converted into AC power is immediately supplied to the load 16.
検出制御部22は例えば第２図に示すように、入力端子12
a,12b間より検出された商用電源電圧VINが停電検出器23
と、特にこの考案で設けられた移相器24とに供給され
る。移相器24の移相量は、停電になった際に生じる供給
電力欠損時間、つまり無電圧区間（第５図Ａ）とほぼ等
しく選定されてある。As shown in FIG. 2, the detection control unit 22 uses the input terminal 12
The commercial power supply voltage V IN detected between a and 12b is the power failure detector 23
And especially to the phase shifter 24 provided in this invention. The amount of phase shift of the phase shifter 24 is selected to be substantially equal to the supply power loss time that occurs when a power failure occurs, that is, the no-voltage section (FIG. 5A).
この移相器24の出力はいわゆる位相同期ループ（PLL）
で構成された基準発振器25へ基準信号として供給され、
これと位相同期した発振出力が得られ、これが基準発振
信号としてPWM制御器26内の乗算器27へ供給される。さ
らに乗算器27には、インバータ18の出力、すなわち出力
端子15a,15b間の電圧V0、インバータ電流I0（配線19よ
り検出）がそれぞれ基準値と比較された出力が供給さ
れ、インバータ18の出力の電圧V0、電流I0がそれぞれ所
定値に保持されるように制御される。乗算器27の出力は
三角波発生器28の出力と比較器29で比較され、その出力
は波形合成器31へ供給され、波形合成器31の出力はそれ
ぞれゲート32〜35を通じ、更に駆動回路36を通じてトラ
ンジスタQ1〜Q4の対応するものをスイッチング制御す
る。The output of this phase shifter 24 is a so-called phase locked loop (PLL).
Is supplied as a reference signal to the reference oscillator 25 composed of
An oscillation output phase-locked with this is obtained, and this is supplied to the multiplier 27 in the PWM controller 26 as a reference oscillation signal. Further, the output of the inverter 18, that is, the voltage V 0 between the output terminals 15a and 15b and the output obtained by comparing the inverter current I 0 (detected from the wiring 19) with the reference value are supplied to the multiplier 27, and the output of the inverter 18 is supplied. The output voltage V 0 and the current I 0 are controlled so as to be maintained at predetermined values. The output of the multiplier 27 is compared with the output of the triangular wave generator 28 by the comparator 29, and the output is supplied to the waveform synthesizer 31, the output of the waveform synthesizer 31 is passed through the gates 32 to 35, respectively, and further through the drive circuit 36. Switching control of corresponding ones of the transistors Q 1 to Q 4 .
停電検出器23の検出出力はONデイレー回路37を通じて少
なくとも交流スイッチ13の自然消弧時間遅らせてゲート
32〜35を開き、また基準発振器25内の位相比較器の出力
が同期検出器38へ供給され、この出力により、停電回復
時に、インバータ出力と復電された商用電力とが同期状
態になるとゲート32〜35が閉じるようにされる。停電検
出器23の出力によりスイッチ駆動回路39を介して交流ス
イッチ13がオン，オフ制御される。The detection output of the power failure detector 23 is delayed by at least the natural extinguishing time of the AC switch 13 through the ON delay circuit 37 and gated.
32 to 35 are opened, and the output of the phase comparator in the reference oscillator 25 is supplied to the synchronization detector 38, which outputs a gate when the inverter output and the restored commercial power are in a synchronized state at the time of power failure recovery. 32-35 will be closed. The AC switch 13 is ON / OFF controlled by the output of the power failure detector 23 via the switch drive circuit 39.
このように構成されているため、出力端子15a,15b間の
出力電圧は商用電力受電中は第３図Ａ中の実線41に示す
ように商用電圧となり、この時、基準発振器の出力波形
（同期波形）は移相器24の存在により点線42に示すよう
にτだけ遅れて同期発振している。With this configuration, the output voltage between the output terminals 15a and 15b becomes the commercial voltage as shown by the solid line 41 in FIG. 3A during commercial power reception, and at this time, the output waveform of the reference oscillator (synchronous Due to the presence of the phase shifter 24, the waveform) is synchronously oscillated with a delay of τ as shown by the dotted line 42.
停電になると、停電検出器23の出力により交流スイッチ
13は直ちに遮断され、交流スイッチ13の自然消弧に必要
な時間0.5〜1ms程度の遅延時間だけONデイレー回路37で
遅延させてゲート32〜35が開かれてインバータ18に対す
る駆動が行われ、無電圧区間ｂが生じる。この区間ｂが
終わると、基準発振器25の出力によりインバータ18が駆
動される。出力端子15a,15bへ供給される出力電圧は第
３図Ａの実線43に示すようになる。このため出力端子15
a,15bに印加される出力電圧は無電圧区間ｂが存在する
半周期T1は位相差τだけ通常の半周期の期間T0より長く
なり、それだけ電圧時間積が従来より長くなり、この半
サイクルの電圧時間積と次の半サイクルの電圧時間積と
がほゞ等しくなり、切替え時の次の半サイクルで鉄心飽
和を招くおそれがなく、突入電流も生じない。When a power failure occurs, the output of the power failure detector 23 causes the AC switch
13 is immediately shut off, the time required for spontaneous extinction of the AC switch 13 is delayed by the ON delay circuit 37 for a delay time of about 0.5 to 1 ms, the gates 32 to 35 are opened, and the inverter 18 is driven. A voltage section b occurs. When this section b ends, the inverter 18 is driven by the output of the reference oscillator 25. The output voltage supplied to the output terminals 15a and 15b is as shown by the solid line 43 in FIG. 3A. Therefore, output terminal 15
In the output voltage applied to a and 15b, the half cycle T 1 in which the non-voltage section b exists is longer than the normal half cycle period T 0 by the phase difference τ, and the voltage-time product becomes longer than that in the conventional case. The volt-time product of the cycle and the volt-time product of the next half cycle become approximately equal, there is no risk of iron core saturation in the next half cycle at the time of switching, and no inrush current occurs.
上述したように、商用電力からインバータ電力への切替
え休止期間ｂに見合う時間だけ、移相器24で商用電圧の
位相を遅らせ、これにインバータ出力を同期させること
により、鉄心飽和による突入電流を抑圧することがで
き、出力切替え時の出力電圧低下を防止できる。なお、
第３図Ｂ中のIPリミッタレベルは第２図中の整流平滑回
路51、差検出回路52により制限されるレベルである。As described above, the phase shifter 24 delays the phase of the commercial voltage for a time period commensurate with the switching period b from the commercial power to the inverter power, and the inverter output is synchronized with this to suppress the inrush current due to the iron core saturation. It is possible to prevent the output voltage from dropping when the output is switched. In addition,
The IP limiter level in FIG. 3B is a level limited by the rectifying / smoothing circuit 51 and the difference detecting circuit 52 in FIG.
上述においては基準発振器25の入力側に移相器24を設け
たが、出力側に移相器24を挿入してもよい。単相待機運
転式無停電電源装置にのみならず、常時運転式無停電電
源装置や３相無停電電源装置にもこの考案を適用するこ
とができる。Although the phase shifter 24 is provided on the input side of the reference oscillator 25 in the above description, the phase shifter 24 may be inserted on the output side. The present invention can be applied not only to the single-phase standby operation type uninterruptible power supply device, but also to the constant operation type uninterruptible power supply device and the three-phase uninterruptible power supply device.
「考案の効果」 以上述べたようにこの考案によれば、抵抗負荷およびス
イッチングレギュレータ負荷に限らずトランス入力のコ
イル入力負荷においても、切替え回路に安価で過負荷耐
量の大きい自己消弧形スイッチ素子を用いた無停電電源
装置を構成することができる。[Advantage of the Invention] As described above, according to the present invention, the self-extinguishing switch element is inexpensive in the switching circuit and has a large overload resistance not only for the resistance load and the switching regulator load but also for the coil input load of the transformer input. It is possible to configure an uninterruptible power supply using the.
第１図はこの考案による無停電電源装置の一例を示す
図、第２図はこの考案の要部と関連した第１図中の検出
制御部22の具体例を示すブロック図、第３図はこの考案
の動作の説明に供するタイムチャート、第４図は従来の
待機式無停電電源装置を示すブロック図、第５図はその
動作の説明に供するタイムチャート、第６図は各種負荷
を示す図である。FIG. 1 is a diagram showing an example of an uninterruptible power supply device according to the present invention, FIG. 2 is a block diagram showing a concrete example of the detection control unit 22 in FIG. 1 related to the main part of the present invention, and FIG. A time chart for explaining the operation of the present invention, FIG. 4 is a block diagram showing a conventional standby uninterruptible power supply, FIG. 5 is a time chart for explaining the operation, and FIG. 6 is a diagram showing various loads. Is.
Claims (1)
消弧形半導体スイッチを通じて負荷へ供給し、その商用
電力に同期した基準発振信号を得、 停電検出器により停電を検出すると、その検出出力によ
り上記半導体スイッチに対するオン駆動を停止し、かつ
内蔵蓄電池電力を、インバータにより上記基準発振信号
を基準として交流電力に変換し、その変換された交流電
力を上記負荷へ切替え供給する無停電電源装置におい
て、 上記停電検出器の検出出力を少なくとも上記半導体スイ
ッチの自然消弧時間遅延させて、上記インバータよりの
交流電力の供給を遅らせて供給電力欠損時間を設ける手
段と、 上記インバータへ基準として供給する基準発振信号を、
上記供給電力欠損時間とほぼ対応した時間だけ遅延させ
る移相手段とを設けたことを特徴とする無停電電源装
置。1. When commercial power is being received, the commercial power is supplied to a load through a natural arc-extinguishing semiconductor switch, a reference oscillation signal synchronized with the commercial power is obtained, and a power failure detector detects a power failure. An uninterruptible power supply that stops the ON drive to the semiconductor switch by the detection output, and converts the built-in storage battery power to AC power by the inverter with the reference oscillation signal as a reference, and switches the converted AC power to the load. In the apparatus, means for delaying the detection output of the power failure detector at least by the natural extinguishing time of the semiconductor switch, delaying the supply of AC power from the inverter to provide a supply power loss time, and supplying it to the inverter as a reference. The reference oscillation signal
An uninterruptible power supply comprising: a phase shift means for delaying a time substantially corresponding to the supply power loss time.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1987028026U JPH0753390Y2 (en) | 1987-02-25 | 1987-02-25 | Uninterruptible power system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1987028026U JPH0753390Y2 (en) | 1987-02-25 | 1987-02-25 | Uninterruptible power system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63137544U JPS63137544U (en) | 1988-09-09 |
| JPH0753390Y2 true JPH0753390Y2 (en) | 1995-12-06 |
Family
ID=30830611
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1987028026U Expired - Lifetime JPH0753390Y2 (en) | 1987-02-25 | 1987-02-25 | Uninterruptible power system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0753390Y2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4586770B2 (en) * | 2006-06-15 | 2010-11-24 | 株式会社明電舎 | Standby uninterruptible power supply system |
| JP4640361B2 (en) * | 2007-03-15 | 2011-03-02 | 日新電機株式会社 | Parallel compensation type instantaneous voltage drop power failure countermeasure device and instantaneous power failure / power failure countermeasure method, series compensation type instantaneous voltage drop countermeasure device and instantaneous power failure countermeasure method, parallel connection type AC / DC converter with independent operation function and AC / DC conversion method thereof |
| JP6155935B2 (en) * | 2013-07-23 | 2017-07-05 | レシップホールディングス株式会社 | Power supply |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2725539C2 (en) * | 1977-06-06 | 1979-05-10 | Siemens Ag, 1000 Berlin Und 8000 Muenchen | Method for the interruptive switchover of a magnetic load between two AC voltage sources of the same frequency |
| JPS576543A (en) * | 1980-06-12 | 1982-01-13 | Mitsubishi Electric Corp | No-break power source starting system |
-
1987
- 1987-02-25 JP JP1987028026U patent/JPH0753390Y2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63137544U (en) | 1988-09-09 |
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