JPH03265461A - Overcurrent detector for power supply - Google Patents

Overcurrent detector for power supply

Info

Publication number
JPH03265461A
JPH03265461A JP2060122A JP6012290A JPH03265461A JP H03265461 A JPH03265461 A JP H03265461A JP 2060122 A JP2060122 A JP 2060122A JP 6012290 A JP6012290 A JP 6012290A JP H03265461 A JPH03265461 A JP H03265461A
Authority
JP
Japan
Prior art keywords
current
power supply
steady
switching
supply device
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
Application number
JP2060122A
Other languages
Japanese (ja)
Inventor
Shoji Hachisuga
生治 蜂須賀
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fujitsu Ltd
Original Assignee
Fujitsu Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP2060122A priority Critical patent/JPH03265461A/en
Publication of JPH03265461A publication Critical patent/JPH03265461A/en
Pending legal-status Critical Current

Links

Landscapes

  • Direct Current Feeding And Distribution (AREA)
  • Dc-Dc Converters (AREA)

Abstract

PURPOSE:To facilitate protection of a power supply against peak overcurrent and steady overcurrent by stopping function at a switching section when the output current from the power supply exceeds preset short term allowable current and steady allowable current. CONSTITUTION:A current of a load line 27 detected through a CT 4 is rectified 21 and fed through a peak load current detecting section 22 and a diode D2 to a steady load current detecting section 23. A transistor in a switching section (not shown) is subjected to PWM modulation 26 under normal operation. When the peak load current exceeds a preset short term allowable current, voltage across a resistor R1 increases and when it exceeds a predetermined voltage V1, a differential amplifier 24 produces a signal for stopping PWM modulation 26. When the steady load current exceeds a predetermined level for a predetermined time, a voltage divided by resistors R2 and R3 exceeds a predetermined voltage V2 and a differential amplifier 25 produces a signal for stopping PWM 26.

Description

【発明の詳細な説明】 〔概要〕 電源装置における過電流検出装置に係り、特にスイッチ
ング部とこのスイッチング部の制御を行なうスイッチン
グ制御部とを備えてなる電源装置の過電流を検出してス
イッチング部の作動を停止させる過電流検出装置に関し
、 ピーク過電流及び定常過電流に対しても電源装置を保護
することができるようにすることを目的とし、 上述のような過電流検出装置において、電源装置の負荷
線の電流を検出する電流検出手段と、上記負荷線の電流
が予め定めた電源装置の短期許容電流を越えたときに上
記スイッチング制御部にスイッチング部の作動を停止さ
せるピーク負荷電流検出手段と、上記負荷線の電流が予
め定めた電源装置の定常許容電流を越えたときに上記ス
イッチング制御部にスイッチング部の作動を停止させる
定常負荷電流検出手段とを備えて構成する。
[Detailed Description of the Invention] [Summary] It relates to an overcurrent detection device in a power supply device, and in particular, a device for detecting an overcurrent in a power supply device comprising a switching section and a switching control section that controls the switching section. With regard to overcurrent detection devices that stop the operation of current detection means for detecting the current in the load line; and peak load current detection means for causing the switching control unit to stop the operation of the switching unit when the current in the load line exceeds a predetermined short-term allowable current of the power supply device. and steady load current detection means for causing the switching control section to stop the operation of the switching section when the current in the load line exceeds a predetermined steady state allowable current of the power supply device.

〔産業上の利用分野〕[Industrial application field]

本発明は、電源装置の過電流検出装置に係り、特にスイ
ッチング部とこのスイッチング部の制御を行なうスイッ
チング制御部とを備えてなる電源装置の過電流を検出し
てスイッチング部の作動を停止させる過電流検出装置に
関する。
The present invention relates to an overcurrent detection device for a power supply device, and more particularly, the present invention relates to an overcurrent detection device for a power supply device that includes a switching section and a switching control section that controls the switching section. This invention relates to a current detection device.

〔従来の技術〕[Conventional technology]

一般に、電源装置として第3図に示すものがある。同図
において、11は交流電源からの交流電力を整流平滑し
て直流電力を発生する一次側整流平滑手段、12は整流
平滑された直流電力をトランシタTrによりスイッチン
グするスイッチング部、13はスイッチングされた交流
電力を降圧する降圧トランス、14は降圧された電力を
整流平滑する二次側整流平滑手段、15はスイッチング
部を制御するスイッチング制御部を示している。
Generally, there is a power supply device shown in FIG. 3. In the figure, 11 is a primary side rectifying and smoothing means that rectifies and smoothes AC power from an AC power source to generate DC power, 12 is a switching unit that switches the rectified and smoothed DC power by a transistor Tr, and 13 is a switching unit. A step-down transformer that steps down the AC power; 14 is a secondary rectifying and smoothing means that rectifies and smoothes the stepped-down power; and 15 is a switching control section that controls the switching section.

そして同図において16は過電流検出手段で降圧1ヘラ
ンス13の瞬時側コイルに流れる電流を検出する検出ト
ランス17からの信号に基づき、上記の電流が電源装置
の定格を越えるときには、上記スイッチング制御手段1
5に停止信号を発生しスイッチング部12の作動を停止
して電源装置を保護するものとしている。
In the same figure, reference numeral 16 denotes overcurrent detection means, which detects the current flowing in the instantaneous side coil of the step-down voltage transformer 13 based on a signal from the detection transformer 17, and when the above-mentioned current exceeds the rating of the power supply device, the switching control means 1
5, a stop signal is generated to stop the operation of the switching section 12, thereby protecting the power supply device.

ところで現在上記の過電流検出手段とし・てピーク負荷
検出OCA (0ver Current Alarm
)がある。
By the way, peak load detection OCA (0ver Current Alarm) is currently used as the above-mentioned overcurrent detection means.
).

これは、第4図に示すように、装置の電源投入時に発生
するピーク電流を対象とし、許容されるピーク負荷電流
値よりも若干高い値を検出点として設定し、規定ピーク
電流以上の電流が流れた時スイッチング制御部に停止信
号を発生ずるものである。
As shown in Figure 4, this is aimed at the peak current that occurs when the device is powered on, and the detection point is set at a value slightly higher than the allowable peak load current value. When the current flows, a stop signal is generated in the switching control section.

また、過電流の検出手段と1ノて、定常負荷検出OCA
がある。これは第4図に示すように許容される定常電流
値より若干高い値を検出点として設定し、規定定常電流
以上の電流が一定時間流れた時スイッチング制御部に停
止信号を発生するものである。
In addition, the steady load detection OCA is used as an overcurrent detection means.
There is. As shown in Figure 4, this is a detection point set at a value slightly higher than the allowable steady-state current value, and a stop signal is generated to the switching control unit when a current exceeding the specified steady-state current flows for a certain period of time. .

〔発明が解決しようとする課題〕[Problem to be solved by the invention]

しかしながら、上述したピーク負荷検出OCAにあって
は瞬間的なピーク電流に対して電源装置を保護すること
はできるが、設定した規定電流以下であって定常電流の
許容値以上の電流が流れたときには過電流を検出するこ
とができず、通常定常状態を基本として設計された電源
装置にこのような電流が流れた場合には電源装置を保護
することができないという問題がある。
However, although the above-mentioned peak load detection OCA can protect the power supply device against instantaneous peak currents, when the current flows below the set specified current and exceeds the allowable steady-state current, There is a problem in that overcurrent cannot be detected, and if such a current flows through a power supply device that is normally designed on the basis of a steady state, the power supply device cannot be protected.

また上述した定常負荷検出OCAにあっては一定時間以
上にわたる定常過負荷の検出を行なうことができるが、
一定時間以下の瞬時ピーク電流が流れた時には電源装置
を保護することができないという問題がある。
Furthermore, the above-mentioned steady load detection OCA can detect a steady overload over a certain period of time;
There is a problem in that the power supply device cannot be protected when an instantaneous peak current flows for a certain period of time or less.

そこで本発明は、ピーク過電流及び定常過電流に対して
も電源装置を保護することができる電源装置における過
電流検出装置を提供することを目的とする。
SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an overcurrent detection device for a power supply device that can protect the power supply device even against peak overcurrent and steady overcurrent.

(課題を解決するための手段) 本発明にあって、上記の課題を解決するための手段は、
第1図に示すように、スイッチング部1とこのスイッチ
ング部1の制御を行なうスイッチング制御部2とを備え
てなる電源装置の過電流を検出してスイッチング部の作
動を停止させる過電流検出装置において、電源装置の負
荷線3の電流を検出する電流検出手段4と、上記負荷線
3の電流が予め定めた電源装置の短期許容電流を越えた
ときに上記スイッチング制御部2にスイッチング部1の
作動を停止させるピーク負荷電流検出手段5と、上記負
荷線3の電流が予め定めた電源装置の定常許容電流を越
えたときに上記スイッチング制御部2にスイッチング部
1、の作動を停止させる定常負荷電流検出手段6とを備
えたことである。
(Means for solving the problems) In the present invention, the means for solving the above problems are as follows:
As shown in FIG. 1, in an overcurrent detection device that detects an overcurrent of a power supply device comprising a switching section 1 and a switching control section 2 that controls the switching section 1 and stops the operation of the switching section. , a current detection means 4 for detecting the current in the load line 3 of the power supply device; and a current detection means 4 for detecting the current in the load line 3 of the power supply device; peak load current detection means 5 for stopping the operation of the switching unit 1, and a steady load current for causing the switching control unit 2 to stop the operation of the switching unit 1 when the current in the load line 3 exceeds a predetermined steady state allowable current of the power supply device. This is because the detection means 6 is provided.

〔作用) 本発明によれば、電流検出手段は電源装置の負荷線の電
流を検出し、ピーク負荷電流検出手段は上記負荷線の電
流が予め定めた電源装置の短期許容電流を越えたときに
上記スイッチング制御部にスイッチング部の作動を停止
させる。また、定常負荷電流検出手段上記負荷線の電流
が予め定めた電源装置の定常許容電流を越えたときに上
記スイッチング制御部にスイッチング部の作動を停止さ
せるから、ピーク過電流及び定常過電流に対しても電源
装置を保護することができる。
[Operation] According to the present invention, the current detection means detects the current in the load line of the power supply device, and the peak load current detection means detects the current in the load line of the power supply device when the current in the load line exceeds a predetermined short-term allowable current of the power supply device. The switching control section is caused to stop the operation of the switching section. In addition, since the steady load current detection means causes the switching control unit to stop the operation of the switching unit when the current in the load line exceeds a predetermined steady state allowable current of the power supply device, peak overcurrent and steady overcurrent can be prevented. It can also protect the power supply.

〔実施例〕〔Example〕

以下本発明に係る電源装置における過電流検出装置の実
施例を図面に基づいて説明する。
Embodiments of an overcurrent detection device in a power supply device according to the present invention will be described below based on the drawings.

第2図は本発明に係る電源装置における過電流検出装置
の実施例を示すものである。本実施例において、21は
負荷線27の負荷電流を検出する電流検出部であるCT
(C:urrent Trans) 、 22はピーク
負荷検出部、23は定常負荷検出部、24.25は作動
増幅器、26はスイッチング制御部であり、スイッチン
グトランジスタのスイッチングパルス幅を制御するPW
M (puls whidthmodulation)
制御部を示している。このPWM制御部は上記の作動増
幅器24.25からの出力によりスイッチング手段のト
ランジスタを停止させる。そして電流検出部21には整
流用のダイオードD1を設ける一方、ピーク負荷電流検
出部22には電流検出部の出力電圧を取り出す抵抗器R
1を設け、この抵抗器R1の一端部からピーク負荷電流
信号を取り出すものとしている。尚この抵抗器R1には
雑音防止用の低容量のコンデンサC1を並列に設けてい
る。
FIG. 2 shows an embodiment of an overcurrent detection device in a power supply device according to the present invention. In this embodiment, reference numeral 21 denotes a current detection unit CT that detects the load current of the load line 27.
(C: current Trans), 22 is a peak load detection section, 23 is a steady load detection section, 24.25 is an operational amplifier, and 26 is a switching control section, in which PW controls the switching pulse width of the switching transistor.
M (puls width modulation)
The control section is shown. This PWM controller stops the transistor of the switching means by the output from the operational amplifier 24, 25 mentioned above. The current detection section 21 is provided with a rectifying diode D1, and the peak load current detection section 22 is equipped with a resistor R for taking out the output voltage of the current detection section.
1 is provided, and the peak load current signal is taken out from one end of this resistor R1. Note that a low capacitance capacitor C1 for noise prevention is provided in parallel with this resistor R1.

そして、定常負荷電流検出部23はこの抵抗R1の両端
からの電圧をダイオードD2を介して取り出し、二つの
抵抗器R2,R3に印加し、抵抗器R3に並列にコンデ
ンサC2を設けるものとし、このコンデンサC2の一端
の電圧を定常負荷電流信号として取り出すものとしてる
。これらの信号が入力される作動増幅器24.25には
、それぞれ前述のピーク負荷検出値及び定常負荷検出値
に相当する電圧を発生する基準電圧発生手段Vl、V2
を負側に設け、入力する測定電圧が基準電圧より高くな
った時のみ信号を出力するためダイオードD3.D4を
介して上述のPWM制御部26に停止信号を発生するも
のとしている。
Then, the steady load current detection section 23 takes out the voltage from both ends of this resistor R1 via a diode D2 and applies it to two resistors R2 and R3, and a capacitor C2 is provided in parallel with the resistor R3. The voltage at one end of the capacitor C2 is taken out as a steady load current signal. The operational amplifiers 24 and 25 to which these signals are input include reference voltage generating means Vl and V2 that generate voltages corresponding to the aforementioned peak load detection value and steady load detection value, respectively.
are provided on the negative side, and a diode D3. A stop signal is generated to the above-mentioned PWM control unit 26 via D4.

次に本実施例にかかる電源装置における過電流検出装置
の作動を説明する。正常運転時にはスイッチング部のト
ランジスタはPWM制御部により制御されスイッチング
を行なっている。
Next, the operation of the overcurrent detection device in the power supply device according to this embodiment will be explained. During normal operation, the transistors in the switching section are controlled by the PWM control section to perform switching.

そしてピーク負荷電流がピーク電流負荷検出値を越える
と抵抗R1の電圧が上昇し、作動増幅器24は停止信号
を出力してスイッチングトランジスタの作動は停止する
Then, when the peak load current exceeds the peak current load detection value, the voltage of the resistor R1 increases, the operational amplifier 24 outputs a stop signal, and the operation of the switching transistor is stopped.

また、定常負荷電流が定常電流負荷検出値を越えると抵
抗R1に表れる電圧は抵抗器R2と抵抗器R3によって
分圧され、出力端子には抵抗R2,R3及びコンデンサ
C2の時定数により遅れた出力電圧が表れ、また、−度
コンデンサC2に蓄えられた電流は上述した時定数によ
り放電される。よって、負荷線27に定常電流設定値よ
り大きい電流が一定時間流れると出力端子は設定電圧値
に到達し、作動増幅器は停止信号を出力してスイッチン
グトランジスタの作動は停止する。
Furthermore, when the steady load current exceeds the steady current load detection value, the voltage appearing on resistor R1 is divided by resistor R2 and resistor R3, and the output terminal is outputted with a delay due to the time constant of resistors R2, R3 and capacitor C2. A voltage appears and the current stored in the -degree capacitor C2 is discharged according to the above-mentioned time constant. Therefore, when a current larger than the steady current setting value flows through the load line 27 for a certain period of time, the output terminal reaches the set voltage value, the operational amplifier outputs a stop signal, and the operation of the switching transistor is stopped.

従って、本実施例によれば、単一の電流検出部を用い、
比較的簡単な回路構成でピーク過電流及び定常過電流に
対しても電源装置を保護することができる。
Therefore, according to this embodiment, using a single current detection section,
The power supply device can be protected against peak overcurrent and steady overcurrent with a relatively simple circuit configuration.

〔発明の効果〕〔Effect of the invention〕

以上説明したように、本発明によれば、電源装置の負荷
線の電流を検出する電流検出手段と、上記負荷線の電流
が予め定めた電源装置の短期許容電流を越えたときに上
記スイッチング制御部にスイッチング部の作動を停止さ
せるピーク負荷電流検出手段と、上記負荷線の電流が予
め定めた電源装置の定常許容電流を越えたときに上記ス
イッチング制御部にスイッチング部の作動を停止させる
定常負荷電流検出手段とを設けることとしたから、ピー
ク過電流及び定常過電流に対しても電源装置を保護する
ことができるという効果を奏する。
As explained above, according to the present invention, there is provided a current detecting means for detecting a current in a load line of a power supply device, and a switching control device that detects a current in a load line of a power supply device when the current in the load line exceeds a predetermined short-term allowable current of the power supply device. peak load current detection means for stopping the operation of the switching section in the section; and a steady load for causing the switching control section to stop the operation of the switching section when the current in the load line exceeds a predetermined steady state allowable current of the power supply device. Since the current detecting means is provided, the power supply device can be protected against peak overcurrent and steady overcurrent.

【図面の簡単な説明】[Brief explanation of drawings]

第1区は本発明の原理図、第2図は本発明に係る電源装
置における過電流検出装置の実施例を示すブロック図、
第3図は従来の電源装置における過電流検出装置を示す
ブロック図、第4図は過電流の検出点を示す図である。 1・・・スイッチング部 2・・・スイッチング制御部 3・・・負荷線 4・・・電流検出手段 5・・・ピーク負荷電流検出手段 6・・・定常負荷電流検出手段 従来の技術 第3図
The first section is a principle diagram of the present invention, and FIG. 2 is a block diagram showing an embodiment of an overcurrent detection device in a power supply device according to the present invention.
FIG. 3 is a block diagram showing an overcurrent detection device in a conventional power supply device, and FIG. 4 is a diagram showing overcurrent detection points. 1...Switching section 2...Switching control section 3...Load line 4...Current detection means 5...Peak load current detection means 6...Steady load current detection means Conventional technology Fig. 3

Claims (1)

【特許請求の範囲】  スイッチング部(1)とこのスイッチング部(1)の
制御を行なうスイッチング制御部(2)とを備えてなる
電源装置の過電流を検出してスイッチング部の作動を停
止させる過電流検出装置において、 電源装置の負荷線(3)の電流を検出する電流検出手段
(4)と、 上記負荷線(3)の電流が予め定めた電源装置の短期許
容電流を越えたときに上記スイッチング制御部(2)に
スイッチング部(1)の作動を停止させるピーク負荷電
流検出手段(5)と、上記負荷線(3)の電流が予め定
めた電源装置の定常許容電流を越えたときに上記スイッ
チング制御部(2)にスイッチング部(1)の作動を停
止させる定常負荷電流検出手段(6)とを備えたことを
特徴とする電源装置における過電流検出装置。
[Claims] An overcurrent system that detects an overcurrent in a power supply device that includes a switching section (1) and a switching control section (2) that controls the switching section (1) and stops the operation of the switching section. The current detection device includes a current detection means (4) for detecting the current in the load line (3) of the power supply device; The switching control unit (2) includes a peak load current detection means (5) for stopping the operation of the switching unit (1), and a peak load current detection means (5) for stopping the operation of the switching unit (1) when the current in the load line (3) exceeds a predetermined steady state allowable current of the power supply device. An overcurrent detection device in a power supply device, characterized in that the switching control section (2) includes steady load current detection means (6) for stopping operation of the switching section (1).
JP2060122A 1990-03-13 1990-03-13 Overcurrent detector for power supply Pending JPH03265461A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2060122A JPH03265461A (en) 1990-03-13 1990-03-13 Overcurrent detector for power supply

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2060122A JPH03265461A (en) 1990-03-13 1990-03-13 Overcurrent detector for power supply

Publications (1)

Publication Number Publication Date
JPH03265461A true JPH03265461A (en) 1991-11-26

Family

ID=13133008

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2060122A Pending JPH03265461A (en) 1990-03-13 1990-03-13 Overcurrent detector for power supply

Country Status (1)

Country Link
JP (1) JPH03265461A (en)

Similar Documents

Publication Publication Date Title
JP2784463B2 (en) AC line stabilization circuit
JPS6159069B2 (en)
JPH03265461A (en) Overcurrent detector for power supply
JPS61244271A (en) Switching regulator
JPS63287364A (en) Auxiliary power circuit for switching regulator
JP2002165454A (en) Ac voltage regulator
KR20080095740A (en) High voltage power supply
JP7413754B2 (en) Semiconductor drive equipment and power conversion equipment
JP2605304Y2 (en) Protection circuit of the switching regulator
JPH1080138A (en) Overcurrent detection circuit
JPH01311819A (en) Protective circuit for overcurrent of semiconductor power conversion device
KR0155104B1 (en) Abnormal voltage protection circuit of power supply
JPH04200276A (en) Power supply device
KR0120963Y1 (en) The protecting circuit for output short in switching power supply
KR0143256B1 (en) Abnormal voltage protection circuit of smps
JPH0343836Y2 (en)
JPH0729708Y2 (en) Power protection circuit
JPH02155424A (en) Protector for inverter controlled power supply
JPH0698537A (en) Switching power supply device
JPH0534228Y2 (en)
KR900009469Y1 (en) Overcurrent protective circuit
JPH09172772A (en) Power supply apparatus having drooping characteristics of output voltage
KR970004437B1 (en) Switching power trans. secondary rectifying short protection circuit
KR890008921Y1 (en) Over current protective circuit
JPS60139174A (en) Switching power source