JP2655431B2 - Constant flow control device for centrifugal compressor - Google Patents

Constant flow control device for centrifugal compressor

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Publication number
JP2655431B2
JP2655431B2 JP1082864A JP8286489A JP2655431B2 JP 2655431 B2 JP2655431 B2 JP 2655431B2 JP 1082864 A JP1082864 A JP 1082864A JP 8286489 A JP8286489 A JP 8286489A JP 2655431 B2 JP2655431 B2 JP 2655431B2
Authority
JP
Japan
Prior art keywords
flow rate
centrifugal compressor
pressure
discharge
value
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
Application number
JP1082864A
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Japanese (ja)
Other versions
JPH02259298A (en
Inventor
幸三 井岡
良行 小河
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.)
IHI Corp
Original Assignee
IHI Corp
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 IHI Corp filed Critical IHI Corp
Priority to JP1082864A priority Critical patent/JP2655431B2/en
Publication of JPH02259298A publication Critical patent/JPH02259298A/en
Application granted granted Critical
Publication of JP2655431B2 publication Critical patent/JP2655431B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Description

【発明の詳細な説明】 [産業上の利用分野] この発明は加圧流体をプラントへ連続供給する遠心圧
縮機の運転方法に係り、特に遠心圧縮機のサージング等
を防止しつつ吐出流量を選択した流量値に保持させるよ
うにした遠心圧縮機の定流量制御方法に関する。
The present invention relates to an operation method of a centrifugal compressor for continuously supplying a pressurized fluid to a plant, and particularly to selecting a discharge flow rate while preventing surge of the centrifugal compressor. The present invention relates to a method for controlling a constant flow rate of a centrifugal compressor in which a constant flow rate value is maintained.

[従来の技術] 一定圧力の加圧流体をプラントへ効率よく連続供給す
る圧縮機としては、第4図に示すように構成した遠心圧
縮機1がある。
[Related Art] A centrifugal compressor 1 configured as shown in FIG. 4 is an example of a compressor that efficiently and continuously supplies a pressurized fluid having a constant pressure to a plant.

図示されるようにこの遠心圧縮機1は、遠心圧縮機1
の吸込側に、遠心圧縮機1のインペラに対する吸込み空
気の流入量を変えて遠心圧縮機1の圧力−流量曲線を変
えるガイドベーン2を設け、遠心圧縮機1の吐出下流に
圧縮空気の一部を外部に放出してサージングを防止する
放風制御弁3を設けて主に構成される。
As shown in the figure, the centrifugal compressor 1 is
A guide vane 2 for changing the pressure-flow curve of the centrifugal compressor 1 by changing the flow rate of the suction air into the impeller of the centrifugal compressor 1 is provided on the suction side of the centrifugal compressor 1, and a part of the compressed air is provided downstream of the discharge of the centrifugal compressor 1. Is mainly provided with a blow-off control valve 3 for releasing surging to prevent surging.

この遠心圧縮機1は、遠心圧縮機を駆動する駆動モー
タ(図示せず)の使用負荷をオーバーロード調節計4
で、吐出空気圧を圧力指示調節計5で、遠心圧縮機1の
下流の差圧を計測する差圧発信器6でそれぞれ検出する
ように構成されているオーバーロード調節計4の指示お
よび圧力指示調節計5の指示を比較し一方の指示を優先
する選択器7の分析結果に基づいてガイドベーン2の開
度を自動的に調節する。そして差圧発信器6の計測値に
基づく流量指示調節計8によって放風制御弁3を開閉制
御するようにしている。
The centrifugal compressor 1 uses an overload controller 4 to control the load used by a drive motor (not shown) for driving the centrifugal compressor.
The indication and pressure indication adjustment of the overload controller 4 which is configured to detect the discharge air pressure by the pressure indication controller 5 and the differential pressure transmitter 6 for measuring the differential pressure downstream of the centrifugal compressor 1 respectively. The instructions of the total 5 are compared, and the opening of the guide vane 2 is automatically adjusted based on the analysis result of the selector 7 which gives priority to one of the instructions. Then, the blow-off control valve 3 is controlled to be opened and closed by a flow rate indicating controller 8 based on the measurement value of the differential pressure transmitter 6.

[発明が解決しようとする課題] ところで第3図に示してあるように上述の遠心圧縮機
は、サージング流量以上の流量で使用されているうちは
問題ないが、B点以下の流量域で制御を実行するために
は、放風制御弁3を開作動してサージングを防止しつつ
ラインへの流量を一定に保つ必要がある。しかし、放風
させながら一定圧力に保つ制御は、圧縮された空気を放
出するので、圧縮に使われたエネルギを損失するロスが
ある。
[Problems to be Solved by the Invention] As shown in FIG. 3, the above-described centrifugal compressor has no problem while being used at a flow rate higher than the surging flow rate, but is controlled in a flow rate range below point B. It is necessary to keep the flow to the line constant while opening the blow-off control valve 3 to prevent surging. However, the control of maintaining a constant pressure while blowing air releases the compressed air, so there is a loss of losing the energy used for compression.

[課題を解決するための手段] この発明は上記課題を解決することを目的とし、遠心
圧縮機の吸入側に接続され吸込流量を調節するガイドベ
ーンと、上記圧縮機の特定段の圧気を早くサージングす
る段をバイパスして中間段の吸込側へ戻すバイパス通路
と、そのバイパス通路に接続されたバイパス弁と、上記
圧縮機の吐出側に接続され吐出流量を検出するための差
圧発信器と、吐出圧力を検出する圧力発信器と、差圧発
信器と圧力発信器の検出値が入力されると共にバイパス
弁とガイドベーンとを制御するコントローラとを備え、
上記コントローラに段階的に設定した流量のうち任意の
指定流量を入力し、コントローラが、入力された指定流
量値に基づいてバイパス弁の開閉を行い、かつ、上記差
圧測定値と吐出圧力検出値から吐出流体の重量流量を演
算すると共に、その重量流量が、入力された指定流量値
となるように上記ガイドベーンの開度を制御するように
したものである。
Means for Solving the Problems An object of the present invention is to solve the above problems, and a guide vane connected to a suction side of a centrifugal compressor to adjust a suction flow rate, and to increase the pressure of a specific stage of the compressor quickly. A bypass passage for bypassing the surging stage and returning to the suction side of the intermediate stage, a bypass valve connected to the bypass passage, and a differential pressure transmitter connected to the discharge side of the compressor for detecting a discharge flow rate; A pressure transmitter for detecting the discharge pressure, and a controller for controlling the bypass valve and the guide vane while receiving the detection values of the differential pressure transmitter and the pressure transmitter,
An arbitrary designated flow rate among the flow rates set in steps in the controller is input, the controller opens and closes the bypass valve based on the input designated flow rate value, and the differential pressure measurement value and the discharge pressure detection value , The weight flow rate of the discharge fluid is calculated, and the opening degree of the guide vane is controlled such that the weight flow rate becomes the input designated flow rate value.

[作用] コントローラに段階的に設定した流量のうち任意の指
定流量を入力すると、コントローラは、入力された指定
流量値に基づいてバイパス弁の開閉を行う。そして、差
圧発信器で測定される差圧測定値と圧力発信器で検出さ
れる吐出圧力検出値から吐出流体の重量流量を演算する
と共に、その重量流量が、入力された指定流量値となる
ように上記ガイドベーンの開度を制御する。このため、
遠心圧縮機はサージングを発生させることなく一定流量
で運転される。
[Operation] When an arbitrary designated flow rate is input among the flow rates set stepwise to the controller, the controller opens and closes the bypass valve based on the input designated flow rate value. Then, the weight flow rate of the discharge fluid is calculated from the differential pressure measurement value measured by the differential pressure transmitter and the discharge pressure detection value detected by the pressure transmitter, and the weight flow rate becomes the input designated flow rate value. Thus, the opening degree of the guide vane is controlled. For this reason,
The centrifugal compressor operates at a constant flow rate without generating surging.

[実施例] 以下にこの発明の好適一実施例を添付図面に基づいて
説明する。
Hereinafter, a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

まず遠心圧縮機の構成を第1図のフローシートに基づ
いて説明する。
First, the configuration of the centrifugal compressor will be described based on the flow sheet of FIG.

実施例にあって遠心圧縮機1は、流体(空気)を吸い
込みつつ圧縮して吐出する圧縮部を吐出方向に直列に3
段連結して構成される。
In the embodiment, the centrifugal compressor 1 includes a compression unit that sucks a fluid (air) and compresses and discharges the fluid (air) in series in the discharge direction.
It is configured by connecting in stages.

各圧縮部10〜12はインペラ13と、そのインペラ13を回
転自在に収容する圧縮部ケーシング14から成る。各イン
ペラ13の駆動軸(図示せず)は、フレキシブルカップリ
ングまたはギヤカップリングの駆動力伝達機構(図示せ
ず)で連結される。即ち1つの駆動モータ(図示せず)
でこれら駆動軸を連動するように構成し、3段(多段)
の遠心圧縮機1を構成する。
Each of the compression units 10 to 12 includes an impeller 13 and a compression unit casing 14 that rotatably accommodates the impeller 13. A drive shaft (not shown) of each impeller 13 is connected by a drive force transmission mechanism (not shown) of a flexible coupling or a gear coupling. That is, one drive motor (not shown)
These drive shafts are linked to each other, and are configured in three stages (multistage).
Of the centrifugal compressor 1 of FIG.

1段圧縮部10には、その吸込み側にインペラ13に対す
る吸込空気の吸込空気流量を変え、遠心圧縮機1の圧力
−流量曲線を変えるガイドベーン2が設けられている。
このガイドベーン2は、アクチュエータ(図示せず)等
の駆動機構で駆動される。実施例にあって、3段圧縮部
12の吐出部下流とプラント(図示せず)とを接続する圧
力流体搬送路15の下流には、圧縮空気の一部を、1段圧
縮部10と2段圧縮部11との間に戻してサージングを防止
するバイパス通路16が接続されており、このバイパス通
路16にはバイパス通路16を開閉するバイパス弁17が設け
られている。
The first-stage compression section 10 is provided on its suction side with a guide vane 2 for changing a suction air flow rate of suction air to the impeller 13 and changing a pressure-flow rate curve of the centrifugal compressor 1.
The guide vane 2 is driven by a drive mechanism such as an actuator (not shown). In the embodiment, a three-stage compression unit
A part of the compressed air is returned between the first-stage compression unit 10 and the second-stage compression unit 11 downstream of the pressure fluid conveyance path 15 connecting the downstream of the discharge unit 12 and the plant (not shown). A bypass passage 16 for preventing surging is connected. The bypass passage 16 is provided with a bypass valve 17 for opening and closing the bypass passage 16.

このように、1段圧縮部10のインペラ13の前にガイド
ベーン2を設けることによって遠心圧縮機1の流量を調
節できるように構成し、3段圧縮部12より下流の圧力流
体搬送路15に設けた逆止弁18の上流をバイパス弁17で解
放できるように構成することで遠心圧縮機1の定圧・流
量運転を可能する。
As described above, the guide vane 2 is provided in front of the impeller 13 of the first-stage compression section 10 so that the flow rate of the centrifugal compressor 1 can be adjusted. The configuration in which the upstream of the check valve 18 provided can be released by the bypass valve 17 enables the constant-pressure / flow-rate operation of the centrifugal compressor 1.

ところで、3段圧縮部12と逆止弁18間の圧力流体搬送
路15には、遠心圧縮機1の吐出流量を差圧で計測する差
圧発生器24と差圧発信器6が設けられ、逆止弁18の下流
側の吐出圧力を検出する圧力発信器25が設けられてお
り、差圧発信器6と圧力発信器25は上記ガイドベーン2
の開度を調節し、上記バイパス弁を開閉制御するコント
ローラ(CPU等)19の入力出部(IOポート等)20に検出
差圧値を入力するようにしてある。
By the way, a differential pressure generator 24 and a differential pressure transmitter 6 for measuring the discharge flow rate of the centrifugal compressor 1 by a differential pressure are provided in the pressure fluid conveying path 15 between the three-stage compression section 12 and the check valve 18. A pressure transmitter 25 for detecting the discharge pressure on the downstream side of the check valve 18 is provided, and the differential pressure transmitter 6 and the pressure transmitter 25 are connected to the guide vanes 2.
The detected differential pressure value is input to an input / output unit (IO port or the like) 20 of a controller (CPU or the like) 19 that controls the opening of the bypass valve by controlling the opening of the bypass valve.

実施例にあってコントローラ19は、入出力部20、記憶
部21および演算制御部22等から構成され、その記憶部21
には第2図に示す遠心圧縮機1の流量−吐出圧力に応じ
て上記制御が自動的に出来るプログラムが内蔵されてい
る。
In the embodiment, the controller 19 includes an input / output unit 20, a storage unit 21, an arithmetic control unit 22, and the like.
Has a built-in program that can automatically perform the above control in accordance with the flow rate-discharge pressure of the centrifugal compressor 1 shown in FIG.

ここで、演算制御部22はセレクトスイッチや遠隔コン
トローラ23の切換えあるいは指令にしたがって、上記ガ
イドベーン2の開閉制御をするとともに、上記バイパス
弁17を開閉制御し、遠心圧縮機1の吐出流量を一定流量
に固定する定流量制御を実行するように構成してある。
Here, the arithmetic and control unit 22 controls the opening and closing of the guide vane 2 and the opening and closing of the bypass valve 17 in accordance with the switching or command of the select switch or the remote controller 23, and controls the discharge flow rate of the centrifugal compressor 1 to a constant value. It is configured to execute constant flow rate control that fixes the flow rate.

つまり演算制御部22は第2図に示してあるように、A
点(100%流量)からB点(50%流量)までの流量区間
を複数に区切り(この例だと50,60,70…100%の10%間
隔で区切る)、セレクトスイッチや遠隔コントローラ23
の切換えあるいは指令によって指定された流量値(%)
にガイドベーン2の開度を自動的に制御を実行する一方
で、検出差圧値および吐出圧力値から吐出流体の重量流
量を演算しつつ、その重量流量の演算値が予め規定した
設定値以下のときは上記バイパス弁17を全開にし設定値
以上のときは上記バイパス弁17を適正開度にする補正制
御を実行し、吐出下流の流体の一部を上記1段圧縮部10
と2段圧縮部11との間に戻すように構成してある。
That is, as shown in FIG.
The flow section from point (100% flow rate) to point B (50% flow rate) is divided into multiple sections (in this example, 50,60,70 ... 100% at 10% intervals), select switch and remote controller 23
Value (%) specified by switching or command
While automatically controlling the opening degree of the guide vane 2, while calculating the weight flow rate of the discharge fluid from the detected differential pressure value and the discharge pressure value, the calculated value of the weight flow rate is equal to or less than a predetermined set value. In this case, the bypass valve 17 is fully opened, and when the pressure is equal to or greater than the set value, a correction control is performed to set the bypass valve 17 to an appropriate opening degree.
And between the two-stage compression unit 11.

したがって設定流量の変化に伴って発生するサージン
グを防止することが可能になり、遠心圧縮機1は指定さ
れた一定吐出流量の運転を継続する。
Therefore, it is possible to prevent surging caused by a change in the set flow rate, and the centrifugal compressor 1 continues to operate at the specified constant discharge flow rate.

つまり実質的に流量−吐出圧力性能IIを高流量側から
低流量側へ圧縮された空気を大気放出することなく移動
することが可能になり、遠心圧縮機1の使用範囲を拡張
することができる。
That is, it is possible to substantially move the flow rate-discharge pressure performance II from the high flow rate side to the low flow rate side without releasing the compressed air to the atmosphere, thereby expanding the range of use of the centrifugal compressor 1. .

但し、演算制御部22は、一定の流量値(%)から他の
流量値(%)に変更する場合、事前の流量値(%)の隣
接側から変更側の流量値(%)に順次移動させるように
制御するようにし、この制御によって圧力の急激な変動
による遠心圧縮機1およびプラントの急激な圧力変動を
防止するように構成される。
However, when changing from a certain flow value (%) to another flow value (%), the arithmetic control unit 22 sequentially moves from the adjacent side of the previous flow value (%) to the flow value (%) on the changed side. The centrifugal compressor 1 and the plant are configured to prevent a sudden change in pressure due to a sudden change in pressure.

ところで、上記遠隔コントローラ23を、上記演算制御
部22に制御信号を送信してそのセレクトスイッチのセレ
クトポジションを決定するように構成すると、遠心圧縮
機1の制御側と遠心圧縮機1の操作側とに区別できるか
ら、操作側ではセレクトスイッチの操作のみで遠心圧縮
機1の流量設定が可能になり、制御の単純化を図ること
ができる。
By the way, if the remote controller 23 is configured to transmit a control signal to the arithmetic control unit 22 to determine the select position of the select switch, the control side of the centrifugal compressor 1 and the operation side of the centrifugal compressor 1 Therefore, on the operation side, the flow rate of the centrifugal compressor 1 can be set only by operating the select switch, and the control can be simplified.

[発明の効果] 以上説明したことから明らかなようにこの発明によれ
ば次の如き優れた効果を発揮する。
[Effects of the Invention] As is clear from the above description, according to the present invention, the following excellent effects are exhibited.

圧縮された空気を大気放出することなく遠心圧縮機の
サージングを防止しつつプラントが要求する流量値に遠
心圧縮機を制御することができる。
The centrifugal compressor can be controlled to a flow rate value required by the plant while preventing surging of the centrifugal compressor without releasing the compressed air to the atmosphere.

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

第1図はこの発明の好適一実施例を示すフローシート、
第2図および第3図は遠心圧縮機の流量−圧力性能線
図、第4図は従来例としての遠心圧縮機のフローシート
である。 図中、1は遠心圧縮機、2はガイドベーン、16はバイパ
ス通路、17はバイパス弁、19はコントローラである。
FIG. 1 is a flow sheet showing a preferred embodiment of the present invention;
2 and 3 are flow rate-pressure performance diagrams of the centrifugal compressor, and FIG. 4 is a flow sheet of a conventional centrifugal compressor. In the figure, 1 is a centrifugal compressor, 2 is a guide vane, 16 is a bypass passage, 17 is a bypass valve, and 19 is a controller.

Claims (1)

(57)【特許請求の範囲】(57) [Claims] 【請求項1】遠心圧縮機の吸入側に接続され吸込流量を
調節するガイドベーンと、上記圧縮機の特定段の圧気を
早くサージングする段をバイパスして中間段の吸込側へ
戻すバイパス通路と、そのバイパス通路に接続されたバ
イパス弁と、上記圧縮機の吐出側に接続され吐出流量を
検出するための差圧発信器と、吐出圧力を検出する圧力
発信器と、差圧発信器と圧力発信器の検出値が入力され
ると共にバイパス弁とガイドベーンとを制御するコント
ローラとを備え、上記コントローラに段階的に設定した
流量のうち任意の指定流量を入力し、コントローラが、
入力された指定流量値に基づいてバイパス弁の開閉を行
い、かつ、上記差圧測定値と吐出圧力検出値から吐出流
体の重量流量を演算すると共に、その重量流量が、入力
された指定流量値となるように上記ガイドベーンの開度
を制御することを特徴とする遠心圧縮機の定流量制御方
法。
1. A guide vane connected to the suction side of a centrifugal compressor for adjusting a suction flow rate, a bypass passage for bypassing a stage for rapidly compressing pressure of a specific stage of the compressor and returning to a suction side of an intermediate stage. A bypass valve connected to the bypass passage, a differential pressure transmitter connected to the discharge side of the compressor for detecting discharge flow rate, a pressure transmitter for detecting discharge pressure, a differential pressure transmitter and pressure A controller that controls the bypass valve and the guide vane while the detection value of the transmitter is input, and inputs any designated flow rate among the flow rates set in the controller in a stepwise manner.
The bypass valve is opened and closed based on the input designated flow rate value, and the weight flow rate of the discharge fluid is calculated from the differential pressure measurement value and the discharge pressure detection value. A constant flow rate control method for a centrifugal compressor, characterized in that the opening degree of the guide vanes is controlled so that
JP1082864A 1989-03-31 1989-03-31 Constant flow control device for centrifugal compressor Expired - Lifetime JP2655431B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP1082864A JP2655431B2 (en) 1989-03-31 1989-03-31 Constant flow control device for centrifugal compressor

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1082864A JP2655431B2 (en) 1989-03-31 1989-03-31 Constant flow control device for centrifugal compressor

Publications (2)

Publication Number Publication Date
JPH02259298A JPH02259298A (en) 1990-10-22
JP2655431B2 true JP2655431B2 (en) 1997-09-17

Family

ID=13786198

Family Applications (1)

Application Number Title Priority Date Filing Date
JP1082864A Expired - Lifetime JP2655431B2 (en) 1989-03-31 1989-03-31 Constant flow control device for centrifugal compressor

Country Status (1)

Country Link
JP (1) JP2655431B2 (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4191563B2 (en) * 2003-08-28 2008-12-03 三菱重工業株式会社 Compressor control method
JP2009024582A (en) * 2007-07-19 2009-02-05 Ihi Corp Gas compression device and method for controlling gas compression device
JP5817488B2 (en) * 2011-12-09 2015-11-18 ダイキン工業株式会社 Refrigeration equipment

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS49123607U (en) * 1973-02-16 1974-10-23

Also Published As

Publication number Publication date
JPH02259298A (en) 1990-10-22

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