JPS6026496A - Voltage type inverter device - Google Patents

Voltage type inverter device

Info

Publication number
JPS6026496A
JPS6026496A JP58133252A JP13325283A JPS6026496A JP S6026496 A JPS6026496 A JP S6026496A JP 58133252 A JP58133252 A JP 58133252A JP 13325283 A JP13325283 A JP 13325283A JP S6026496 A JPS6026496 A JP S6026496A
Authority
JP
Japan
Prior art keywords
voltage
circuit
power
inverter
speed
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
JP58133252A
Other languages
Japanese (ja)
Inventor
Takaaki Miyabe
宮部 隆明
Koichi Miyazaki
晃一 宮崎
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.)
Hitachi Ltd
Original Assignee
Hitachi 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 Hitachi Ltd filed Critical Hitachi Ltd
Priority to JP58133252A priority Critical patent/JPS6026496A/en
Publication of JPS6026496A publication Critical patent/JPS6026496A/en
Pending legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02PCONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P27/00Arrangements or methods for the control of AC motors characterised by the kind of supply voltage
    • H02P27/04Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage
    • H02P27/06Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02PCONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P29/00Arrangements for regulating or controlling electric motors, appropriate for both AC and DC motors
    • H02P29/02Providing protection against overload without automatic interruption of supply
    • H02P29/024Detecting a fault condition, e.g. short circuit, locked rotor, open circuit or loss of load
    • H02P29/025Detecting a fault condition, e.g. short circuit, locked rotor, open circuit or loss of load the fault being a power interruption

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Motor And Converter Starters (AREA)
  • Control Of Ac Motors In General (AREA)
  • Inverter Devices (AREA)

Abstract

PURPOSE:To enable to restart an inverter simultaneously upon recovering by maintaining the slip between the inverter frequency and a load rotating speed substantially zero at a power interruption time. CONSTITUTION:The output voltage of a smoothing circuit is detected by a DC voltage detector 15, the DC output voltage is inputted to a speed correcting circuit 16, a deviation from the preset reference voltage is obtained, and the speed correction signal integrated from the deviation is formed and outputted. This speed correcting signal is inputted to a negative input terminal of a subtractor 18 through a switch 17 closed synchronously with the power interruption period detected by a power interruption detector 14, and the corrected speed signal is outputted to a function generator 8 and a gate controller 11. Thus, the operation of the inverter 5 can be continued even during the power interruption.

Description

【発明の詳細な説明】 〔発明の利用分野〕 本発明は、電圧形インバータ装置に保見特に停電から復
電に至る間のインバータ制御の改良に関する。
DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to the improvement of inverter control in a voltage source inverter device, particularly during the period from power outage to power restoration.

〔発明の背景〕[Background of the invention]

電圧形インバータ装置としては、一般に、第1図に示す
構成のものが広く知られている〆(日立評論、1981
年、第63巻、6月号1)11等)。
Generally, the configuration shown in Figure 1 is widely known as a voltage source inverter device (Hitachi Hyoron, 1981
Year, Volume 63, June Issue 1) 11 etc.).

即ち、交流電源1から供給される交流電力を整流装置2
によって整流し、さらにリアクトル3及びコンデンサ4
とからなる平滑回路によって平滑し、この平滑された直
流をインバータ装置5によって所望の周波数及び電圧を
有する交流に変換し、負荷6に供給するようになってい
る。−夕、速度指令信号は周波数に対応した電圧信号と
して信号入力端7から与えられるようになっている。こ
の速度指令信号は関数発生器8によって電圧指令信号に
変換され、減算回路9を介して自動電圧調整器13に入
力されるようになっている。ゲート制御回路11は入力
される速度指令信号と電圧指令信号とに基づいて、イン
バータ回路5のサイリスタ′又は自己消弧形サイリスタ
の点弧信号を出力するようになっている。インバータ回
路5の一力電圧は出力電圧検出器12によって検出され
、この検出電圧は前記減算回路9のマイナス入力端に入
力されている。
That is, the AC power supplied from the AC power source 1 is transferred to the rectifier 2.
further rectified by reactor 3 and capacitor 4
This smoothed direct current is converted into alternating current having a desired frequency and voltage by an inverter device 5, and is supplied to a load 6. - In the evening, the speed command signal is given from the signal input terminal 7 as a voltage signal corresponding to the frequency. This speed command signal is converted into a voltage command signal by a function generator 8 and is input to an automatic voltage regulator 13 via a subtraction circuit 9. The gate control circuit 11 outputs an ignition signal for the thyristor' or the self-extinguishing thyristor of the inverter circuit 5 based on the input speed command signal and voltage command signal. The output voltage of the inverter circuit 5 is detected by the output voltage detector 12, and this detected voltage is input to the minus input terminal of the subtraction circuit 9.

このように構成されるインバータ装置にあって、交流電
源1に停電が発生すると、負荷6にはコンデンサ4の電
荷が供給されることになる。通常、コンデンサ4の容量
は比較的大きなものであることから、インバータ装置の
運転開始にあたって、別途充電回路を介して初期充電が
なされる。従って、上記停電時にコンデンサ4の電荷が
放電されてしまうと、再起動するためには初期と同様の
操作によシコンデンサを充電しなければならず、比較的
長い始動時間を要することになる。そこで従来は、停電
時にコンデンサ4を放電させないようにするため、停電
を検出してインバータ回路5を停止するようにしていた
In the inverter device configured as described above, when a power outage occurs in the AC power supply 1, the charge of the capacitor 4 is supplied to the load 6. Since the capacitor 4 normally has a relatively large capacity, it is initially charged via a separate charging circuit when the inverter device starts operating. Therefore, if the electric charge in the capacitor 4 is discharged during the power outage, the capacitor must be charged by the same operation as the initial operation in order to restart, and a relatively long startup time is required. Conventionally, in order to prevent the capacitor 4 from discharging during a power outage, the inverter circuit 5 was stopped upon detecting the power outage.

ところが、インバータ回路5の運転を停止してしまうと
、復電時即ち停電が回復したときに負荷6の回転数が不
明になってしまうことから、復電と同時に負荷6を再始
動することができなかった。
However, if the operation of the inverter circuit 5 is stopped, the rotational speed of the load 6 will be unknown when the power is restored, that is, when the power outage is restored, so it is difficult to restart the load 6 at the same time as the power is restored. could not.

例えば復電時の負荷1q転数とインバータ回路5の出力
周波数とが一致せず、滑シが大きくなっていた場合には
、負荷6にコンデンサ4から過電流が流れてしまうとと
になる。
For example, if the load 1q rotation number and the output frequency of the inverter circuit 5 do not match when the power is restored, and the slippage becomes large, an overcurrent will flow from the capacitor 4 to the load 6.

〔発明の目的〕[Purpose of the invention]

本発明の目的は、復電と同時に再始動することができる
電圧形インバータ装置を提供することにある。
An object of the present invention is to provide a voltage source inverter device that can restart at the same time as power is restored.

〔発明の概要〕[Summary of the invention]

本発明は、平滑回路の出力電圧又はインバータ回路の出
力電圧を検出し、この検出電圧と基準電圧との偏差を積
分しこの積分値に応じた値の速度補正信号を形成し、交
流電源の停電期間に同期させて速度指令信号から速度補
正信号を減する補正をすることによシ、復電と同時に再
始動させようとするものである。
The present invention detects the output voltage of a smoothing circuit or the output voltage of an inverter circuit, integrates the deviation between this detected voltage and a reference voltage, forms a speed correction signal of a value corresponding to this integrated value, and By subtracting the speed correction signal from the speed command signal in synchronization with the period, restarting is attempted at the same time as power is restored.

〔発明の実施例〕[Embodiments of the invention]

以下、本発明を実施例に基づいて説明する。第2図に本
発明の一実施例のブロック構成図が示されている。同図
において、第1図図示従来例と同一符号の付されたもの
は、同一機能、同一構成を有するものである。
Hereinafter, the present invention will be explained based on examples. FIG. 2 shows a block diagram of an embodiment of the present invention. In the same figure, parts given the same reference numerals as those in the conventional example shown in FIG. 1 have the same functions and configurations.

第2図に示すように、交流電源1の電圧は電圧検出器1
3によって検出され、この検出電圧が停電検出回路14
に入力されている。この停電検出回路14は、例えば交
流電圧が70%以下に低下したとき停電として検出する
ようになっている。
As shown in FIG. 2, the voltage of the AC power supply 1 is detected by the voltage detector 1.
3, and this detected voltage is detected by the power failure detection circuit 14.
has been entered. This power outage detection circuit 14 is configured to detect a power outage when the AC voltage drops to 70% or less, for example.

一方、平滑回路の出力電圧は直流電圧検出回路15によ
って検出されるようになっている。この直流出力電圧は
速度補正回路16に人力され、ここにおいて予め設定さ
れる基準電圧との偏差がめられ、さらにこの偏差を積分
した速度補正信号が形成出力される。この速度補正信号
は前記停電検出回路14によって検出される停電期間に
同期して閉成されるスイッチ17を介して、減算回路1
8のマイナス入力端に入力されるようになっている。こ
の減算回路18のプラス入力端には速度指令信号が入力
されており、この減算回路18の出力は前記関数発生器
8とゲート制御回路11とに入力されるようになってい
る。
On the other hand, the output voltage of the smoothing circuit is detected by a DC voltage detection circuit 15. This DC output voltage is manually inputted to a speed correction circuit 16, where a deviation from a preset reference voltage is detected, and a speed correction signal obtained by integrating this deviation is formed and output. This speed correction signal is transmitted to the subtraction circuit 1 through a switch 17 that is closed in synchronization with the power outage period detected by the power outage detection circuit 14.
It is designed to be input to the minus input terminal of 8. A speed command signal is input to the plus input terminal of this subtraction circuit 18, and the output of this subtraction circuit 18 is input to the function generator 8 and the gate control circuit 11.

このように構成される実施例の動作について以下に説明
する。
The operation of the embodiment configured in this way will be described below.

停電検出回路14によって停電が検出されると同時にス
イッチ17が閉成される。一方、直流電圧検出回路14
によって検出された直流電圧は、速度補正回路16にお
いて基準電圧との偏差(正負極性)がめられ、さらにと
の偏差を積分した速度補正信号(正負極性)が形成され
る。即ち、速度補正回路16の出力部には積分機能が設
けられておシ、出力される速度補正信号は直流出力電圧
の増減に応じた変化が積分された値となっている。この
速度補正信号は前記スイッチ17の閉成時、即ち交流電
源1の停電のみ減算回路18に出力される。減算回路1
8において速度指令信号は前記速度補正信号の分だけ減
じられ、補正された速度信号が関数発生器8とゲート制
御回路11とに出力される。このようにして停電中であ
ってもインバータ回路5の運転を継続するようにし、こ
れによシ変化するコンデンサ4の電荷量、即ち直流電圧
の増減に基づいてインバータ回路5の出力インバータ周
波数を制御するようにして込る。つ″!シインバ〜り周
波数と負荷回転数との滑シを実質的に零に維持している
のである。即ち、停電中はコンデ/す4と負荷6との間
で無効心力の授受が行なわれるので、例えば、負荷6が
電動運転モードにちると、インバータ周波数と負荷回転
数との滑シが正方向へ増大し、コンデンサ4の電荷が負
荷6へ供給されて、直流電圧が下がる。そこで、この直
流電圧の低下を検出した場合は、インバータ回路5のイ
ンバータ周波数を下げ、負荷回転数との滑シを零近傍に
保持するようにし、かつこれによって直流電圧を一定に
保持するようにしている。他方、負荷6が回生運転モー
ドにあると、滑シが負の方向へ増大し、負荷60回生電
力によシコンデンサ4が充電されて直流電圧が上昇する
。この直流電圧の上昇を検出した場合は、インバータ回
路5のインバータ周波数を上げる制御を行ない、これに
よって滑りを零近傍に保持するようにし、且つ直流電圧
を一定に保持するようにしているのである。
The switch 17 is closed at the same time as the power failure is detected by the power failure detection circuit 14. On the other hand, the DC voltage detection circuit 14
The deviation (positive and negative polarity) of the detected DC voltage from the reference voltage is determined in the speed correction circuit 16, and a speed correction signal (positive and negative polarity) is formed by integrating the deviation. That is, the output section of the speed correction circuit 16 is provided with an integration function, and the output speed correction signal is a value obtained by integrating changes in accordance with increases and decreases in the DC output voltage. This speed correction signal is output to the subtraction circuit 18 only when the switch 17 is closed, that is, when the AC power supply 1 is out of power. Subtraction circuit 1
At 8, the speed command signal is subtracted by the speed correction signal, and the corrected speed signal is output to the function generator 8 and the gate control circuit 11. In this way, the operation of the inverter circuit 5 is continued even during a power outage, and the output inverter frequency of the inverter circuit 5 is controlled based on the changing charge amount of the capacitor 4, that is, the increase/decrease in the DC voltage. Do as you like. In other words, during a power outage, reactive force is exchanged between the power converter 4 and the load 6. Therefore, for example, when the load 6 enters the electric operation mode, the slippage between the inverter frequency and the load rotation speed increases in the positive direction, the charge of the capacitor 4 is supplied to the load 6, and the DC voltage decreases. When this drop in DC voltage is detected, the inverter frequency of the inverter circuit 5 is lowered to maintain the slippage with the load rotation speed near zero, and thereby to maintain the DC voltage constant. On the other hand, when the load 6 is in the regenerative operation mode, the slippage increases in the negative direction, the capacitor 4 is charged by the regenerative power of the load 60, and the DC voltage increases.This increase in DC voltage is detected. In this case, control is performed to increase the inverter frequency of the inverter circuit 5, thereby keeping the slippage near zero and keeping the DC voltage constant.

なお、身ンバータ周波数と負荷回転数との滑シを検出す
る手段として、上述した直流電圧の変動検出に変えて、
インバータ回路5の出力電圧の変動を検出しても同様な
制御が行なえる。
In addition, as a means of detecting the slippage between the inverter frequency and the load rotation speed, instead of the above-mentioned DC voltage fluctuation detection,
Similar control can be performed by detecting fluctuations in the output voltage of the inverter circuit 5.

上述したように、本実施例によれば、停電中にあっても
インバータ回路の運転を継続するようにし、しかもその
インバータ周波数を負荷の回転数に一致させるように制
御していることから、コンデンサを放電させることなく
その端子電圧を一定に保持することができる。これによ
って復電と同時にインバータ装置を再始動させても、コ
ンデンサに突入電流が流れることがないので、復電と同
時に直ちにインバータ装置を始動させることができ、こ
れによって負荷を運転することができる。
As described above, according to this embodiment, the inverter circuit continues to operate even during a power outage, and since the inverter frequency is controlled to match the rotational speed of the load, the capacitor The terminal voltage can be held constant without causing discharge. As a result, even if the inverter device is restarted at the same time as the power is restored, no inrush current will flow through the capacitor, so the inverter device can be started immediately at the same time as the power is restored, thereby allowing the load to be operated.

°第3図と第4図に、停電から復電を再始動に至る従来
例と本実施例による負荷回転数のタイムチャートを示す
。従来例によれば停電と同時にインバータ装置を停止さ
せることから、第3図に示すように、負荷運転中のtI
において停電が発生すると、t2において復電されても
負荷が停止するt3まで再始動させることができない。
3 and 4 show time charts of the load rotation speed according to the conventional example and the present embodiment from power failure to power restoration and restart. According to the conventional example, since the inverter device is stopped at the same time as a power outage, as shown in FIG.
If a power outage occurs at , even if the power is restored at t2, the engine cannot be restarted until t3, when the load stops.

そしてt4において始めて始動を開始し、負荷の始動特
性に応じて回転数が上昇され、t5において停電前の回
転数に立ち上げられることになる。これに対して、本実
施例によれば第4図に示すように、t2における復電と
同時にインバータ装置を再始動させることができ、その
時点の回転数からの立ち上げになるので極めて短い時間
で立ち上げが完了する(t6 )。第3図及び第4図か
ら明らかなように本実施例によれば極めて短い時間でイ
ンバータ装置を再始動させることができるという効果が
ある。また負荷回転数の低下時間を極めて短くすること
ができるという効果がある。
Then, starting is started at t4, the rotational speed is increased according to the starting characteristics of the load, and at t5 the rotational speed is increased to the rotational speed before the power outage. On the other hand, according to the present embodiment, as shown in FIG. 4, the inverter device can be restarted at the same time as the power is restored at t2, and the time is extremely short because the inverter device is started from the rotational speed at that time. The startup is completed (t6). As is clear from FIGS. 3 and 4, this embodiment has the advantage that the inverter device can be restarted in an extremely short time. Further, there is an effect that the time during which the load rotational speed decreases can be extremely shortened.

〔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、復電と同時にイ
ンバータ装置を再始動することができるという効果があ
る。
As explained above, according to the present invention, there is an effect that the inverter device can be restarted at the same time as power is restored.

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

第1図は従来例のブロック構成図、第2図は本発明の一
実施例のブロック構成図、第3図は従来例の負荷回転数
変化を示すタイムチャート、第4図は第2図図示実施例
の負荷回転数変化を示すタイムチャートである。 13・・・電圧検出器、14・・・停電検出回路、15
・・・直流電圧検出回路、16・・・速度補正回路、1
7・・・スイッチ、18・・・減算回路。 代理人 弁理士 鵜沼辰之 第 l刀 第20
Fig. 1 is a block diagram of a conventional example, Fig. 2 is a block diagram of an embodiment of the present invention, Fig. 3 is a time chart showing changes in the load rotation speed of the conventional example, and Fig. 4 is a diagram shown in Fig. 2. It is a time chart which shows the load rotation speed change of an Example. 13... Voltage detector, 14... Power outage detection circuit, 15
...DC voltage detection circuit, 16...Speed correction circuit, 1
7...Switch, 18...Subtraction circuit. Agent Patent Attorney Tatsuyuki Unuma Katana No. 20

Claims (1)

【特許請求の範囲】[Claims] 1、交流電源に接続された整流回路と、該整流回路の出
力を平滑するコンデンサを含んでなる平滑回路と、該平
滑回路の直流出力を与えられる速度指令信号に基づいた
電圧及び周波数を有する交流に変換して負荷に供給する
インバータ回路と、全備えてなる電圧形インバータ装置
において、前記交流電源の停電を検出して停電信号を出
力する停電検出回路と、該停電信号によシ閉略されるス
イッチと、前記平滑回路の出力電圧又は前記インバータ
回路の出力電圧を検出する電圧検出回路と、該電圧検出
回路から出力される検出台電圧と基準電圧の偏差を積分
し該積分値に応じた値の速度補正信号を出力する速度補
正回路と、前記スイッチを介して入力され、る前記速度
補正信号を前記速度指令信号から減する減算回路と、を
設けで構成したことを特徴とする電圧形インバータ装置
1. A rectifying circuit connected to an AC power source, a smoothing circuit including a capacitor for smoothing the output of the rectifying circuit, and an AC having a voltage and frequency based on a speed command signal given the DC output of the smoothing circuit. In the voltage source inverter device, the voltage type inverter device is entirely equipped with an inverter circuit that converts the AC power into a power supply and supplies the power to the load, and a power failure detection circuit that detects a power failure of the AC power source and outputs a power failure signal, and a power failure detection circuit that detects a power failure of the AC power source and outputs a power failure signal; a voltage detection circuit that detects the output voltage of the smoothing circuit or the output voltage of the inverter circuit; and a voltage detection circuit that integrates the deviation between the detection stand voltage output from the voltage detection circuit and a reference voltage and calculates the voltage according to the integrated value. A voltage type device comprising: a speed correction circuit that outputs a speed correction signal of a value; and a subtraction circuit that is input via the switch and subtracts the speed correction signal from the speed command signal. Inverter device.
JP58133252A 1983-07-21 1983-07-21 Voltage type inverter device Pending JPS6026496A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP58133252A JPS6026496A (en) 1983-07-21 1983-07-21 Voltage type inverter device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP58133252A JPS6026496A (en) 1983-07-21 1983-07-21 Voltage type inverter device

Publications (1)

Publication Number Publication Date
JPS6026496A true JPS6026496A (en) 1985-02-09

Family

ID=15100261

Family Applications (1)

Application Number Title Priority Date Filing Date
JP58133252A Pending JPS6026496A (en) 1983-07-21 1983-07-21 Voltage type inverter device

Country Status (1)

Country Link
JP (1) JPS6026496A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63109596U (en) * 1987-01-08 1988-07-14
WO1990015474A1 (en) * 1989-06-09 1990-12-13 Hitachi, Ltd. Motor controller
US6005784A (en) * 1996-06-28 1999-12-21 Mitsubishi Denki Kabushiki Kaisha Voltage type inverter device and method of controlling the same

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5234312A (en) * 1975-09-12 1977-03-16 Fuji Electric Co Ltd Auxiliary device for emergency operation of static type frequency conv erter
JPS564390B2 (en) * 1977-08-29 1981-01-29

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5234312A (en) * 1975-09-12 1977-03-16 Fuji Electric Co Ltd Auxiliary device for emergency operation of static type frequency conv erter
JPS564390B2 (en) * 1977-08-29 1981-01-29

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63109596U (en) * 1987-01-08 1988-07-14
WO1990015474A1 (en) * 1989-06-09 1990-12-13 Hitachi, Ltd. Motor controller
US5196769A (en) * 1989-06-09 1993-03-23 Hiroshi Chiba Motor control device
US6005784A (en) * 1996-06-28 1999-12-21 Mitsubishi Denki Kabushiki Kaisha Voltage type inverter device and method of controlling the same
CN1061799C (en) * 1996-06-28 2001-02-07 三菱电机株式会社 Voltage type inverter and control method thereof

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