JPS58219617A - Constant value controlling method - Google Patents
Constant value controlling methodInfo
- Publication number
- JPS58219617A JPS58219617A JP10205282A JP10205282A JPS58219617A JP S58219617 A JPS58219617 A JP S58219617A JP 10205282 A JP10205282 A JP 10205282A JP 10205282 A JP10205282 A JP 10205282A JP S58219617 A JPS58219617 A JP S58219617A
- Authority
- JP
- Japan
- Prior art keywords
- flow rate
- control valve
- control
- total
- fluid
- 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
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D7/00—Control of flow
- G05D7/06—Control of flow characterised by the use of electric means
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Automation & Control Theory (AREA)
- Feedback Control In General (AREA)
- Flow Control (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は、定値制御方法に係り、特に流体の流量の全量
並びに変動量を定値制御するのに好適な定値制御方法に
関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a constant value control method, and more particularly to a constant value control method suitable for constant value control of the total flow rate and fluctuation amount of fluid.
従来の定値制御方法を第１図、第２図により説明する。A conventional fixed value control method will be explained with reference to FIGS. 1 and 2.
第１図、第２図は、例えば、空気の液化深冷分離装置等
で分離された製品ガスを圧縮機で圧縮し送出する際に、
圧縮機での吸入圧力を一定圧力に制御する吸入圧制御装
置の系統図である。Figures 1 and 2 show, for example, when a product gas separated by an air liquefaction cryogenic separation device is compressed by a compressor and sent out.
FIG. 2 is a system diagram of a suction pressure control device that controls suction pressure in a compressor to a constant pressure.
第１図で、圧縮′Ｉａ１０の吸入側には、例えば、空気
の液化深冷分離装置（以下、分離装置と略）（図示省略
）に連結された導管加が、吐出側には、例えば、使用端
（図示省略）に連結された導管２１がそれぞれ連結され
ている。導管加と導管２１とには、圧縮機ｌＯをバイパ
スし導管ｎが連結されている。導管ｍには、圧力調節計
加が設けられ、導管乙には、調節弁旬が設けられている
。調節弁切は、圧力調節計園に接続されている。In FIG. 1, on the suction side of the compression 'Ia10, there is a conduit connected to, for example, an air liquefaction cryogenic separation device (hereinafter abbreviated as the separation device) (not shown), and on the discharge side, for example, Conduits 21 connected to the use ends (not shown) are connected to each other. A conduit n is connected to the conduit connection and the conduit 21, bypassing the compressor lO. The conduit m is provided with a pressure regulator, and the conduit B is provided with a control valve. The control valve cutter is connected to the pressure regulator.
流体である分離装置で分離された製品ガスは、導管加を
経て圧縮機ｌＯに吸入され、ここで、圧縮された後に吐
出され導管２１を経て使用端へ送出される。一方、圧縮
機１０の吸入圧力は、圧力調節計器により調節弁恥の弁
開度を調節し、これにより導管２１を経て使用端へ送出
される途中で一部分流された流体を調節弁荀を介し導管
区な経て導管加を流通する流体に合流させることで一定
圧力に制御される。 、
今、分離装置から導管加を経て圧縮機１０に供給される
流体の流量（以下、供給流量と略）を８０ＯＮ ｒｌ”
／ ｌ（、圧縮機ｌＯの処理風量を１２０ＯＮｍ”／
Ｈと仮定すれば、必然的に導管２１の途中で分流し調節
弁旬な介し導管ｎを流通する流体の流量（以下、バイパ
ス流量と略）は４０ＯＮｍ’／Ｈとなる。また、供給流
量が極端にＯＮｍ”／Ｈとなった場合には、圧縮機１０
の処理風量が１２０ＯＮｍ”／Ｈでみるため、バイパス
流量を１２０ＯＮｍ’／Ｈとしなければ圧縮機１０の吸
入圧力を一定圧カに保つことができない。したがって、
調節弁旬の流量調節容量（以下、容量と略）は最大１２
０ＯＮｍ’／Ｈ必要となる。一方、圧縮機ｌＯの吸入圧
力を、例えば、１００５ｎＡｑ ：ｌ：約５０ｍＡｑ
４ｍ制御すルニは、導管加のポリ−ニームにもよるが、
圧縮機１ｏに吸入される流体の流量（以下、吸入流量と
略）の変動量を数Ｎｍ”／Ｈ以下に抑制しなければなら
ないＯ
つまり、調節弁荀は数Ｎ ｍ” ／ Ｈの制御が可能で
なくてはならないが、しかし、調節弁切の調節限界範囲
（以下、レンジアビリティ−と称す）は通常３３０〜５
０程度であり、調節弁旬の容量を最大１２００ Ｎｍ”
／Ｈとすれば、調節弁荀の最小限容量は４０〜２４Ｎｍ
”／Ｈであり、したがって、このような吸入圧制御装置
では、吸入流量の全量を一定量に制御できるものの、吸
入流量の変動量を一定量内に制御できないといった欠点
があった。The product gas, which is a fluid, separated by the separator is taken into the compressor lO through a conduit, where it is compressed and then discharged and sent to the use end via the conduit 21. On the other hand, the suction pressure of the compressor 10 is controlled by adjusting the valve opening degree of the control valve using a pressure control instrument, so that the fluid that is partially flowed out while being sent to the use end via the conduit 21 is passed through the control valve. The pressure is controlled at a constant level by connecting the conduit to the flowing fluid through the conduit section. Now, the flow rate of the fluid supplied from the separator to the compressor 10 via conduit addition (hereinafter referred to as supply flow rate) is set to 80ON rl.
/ l(, compressor lO processing air volume is 120ONm”/
If it is assumed that the flow rate is H, the flow rate of the fluid flowing through the intervening conduit n (hereinafter abbreviated as bypass flow rate), which necessarily has a branch control valve in the middle of the conduit 21, will be 40 ONm'/H. In addition, if the supply flow rate becomes extremely ONm"/H, the compressor 10
Since the processing air volume is 120ONm'/H, the suction pressure of the compressor 10 cannot be maintained at a constant pressure unless the bypass flow rate is set to 120ONm'/H.
The maximum flow rate adjustment capacity (hereinafter referred to as capacity) of the control valve is 12
0ONm'/H is required. On the other hand, the suction pressure of the compressor lO is set to, for example, 1005 nAq: l: about 50 mAq
4m control luni depends on the polyneem of the conduit,
The amount of fluctuation in the flow rate of fluid sucked into the compressor 1o (hereinafter abbreviated as suction flow rate) must be suppressed to less than a few Nm''/H. However, the adjustment limit range of the control valve (hereinafter referred to as range ability) is usually 330 to 5.
0, and the capacity of the control valve can be up to 1200 Nm.”
/H, the minimum capacity of the control valve is 40 to 24 Nm.
Therefore, although such a suction pressure control device can control the total suction flow rate to a constant amount, it has a drawback that it cannot control the amount of variation in the suction flow rate to within a constant amount.
第２図で、圧縮機ｌＯの吸入側には、例えば、分離装置
（図示省略）に連結された導管加が、吐出側には、例え
ば、使用端（図示省略）に連結された導管４がそれぞれ
連結されている。導管加と導管２１、とには、圧縮機１
０をバイパスし導管ｎが連結されている。導管加には、
圧力調節針園が設けられ、導管ｎには、調節弁４１が設
けられている。導管ρには、調節弁４１をバイパスし導
管ｎが連結されている。導管囚には、調節弁４２が設け
られている。また、調節弁４１．４２は、圧力調節計間
にそれぞれ接続されている。なお、調節弁４１は、調節
弁４２が全開となりても圧縮機１０の処理風量と比較し
吸入流量の全量が不足している場合に、圧力調節針、（
９）により開作動される。In FIG. 2, on the suction side of the compressor IO, there is a conduit 4 connected to, for example, a separation device (not shown), and on the discharge side, for example, a conduit 4 connected to the use end (not shown). Each is connected. The conduit connection and the conduit 21 are connected to the compressor 1.
A conduit n is connected by bypassing 0. For conduit addition,
A pressure regulating needle is provided, and a regulating valve 41 is provided in the conduit n. A conduit n is connected to the conduit ρ, bypassing the control valve 41. A control valve 42 is provided in the conduit. Further, the control valves 41 and 42 are respectively connected between the pressure regulators. Note that even if the control valve 42 is fully opened, the pressure control needle (
9).
今、供給流量を８０ＯＮｍ”／Ｈ，圧縮機１０の処理風
量を１２０ＯＮｍ”／Ｈと仮定すれば、この場合、バイ
パス流量は４０ＯＮｍ”／Ｈとなる。したがって、調節
弁４２の容量を４０ＯＮｍ”／Ｈ以下とすれば、調節弁
４２が必ず全開となりバイパス流量は調節弁４１でのみ
調節されるようになり調節弁４２を設けた意味がなくな
るため、調節弁４２の容量は最大４０ＯＮｍ’／Ｈ以上
となる必要がある。Now, if we assume that the supply flow rate is 80ONm"/H and the processing air volume of the compressor 10 is 120ONm"/H, then in this case, the bypass flow rate will be 40ONm"/H. Therefore, the capacity of the control valve 42 will be 40ONm"/H. If it is below H, the control valve 42 will always be fully open and the bypass flow rate will be regulated only by the control valve 41, so there is no point in providing the control valve 42, so the maximum capacity of the control valve 42 should be 40 ONm'/H or more. It is necessary to
そこで、調節弁４２の容量を最大４０ＯＮｍ”／Ｈとし
たとしても通常のレンジアビリティ−３０〜５０程度で
は、１３〜８Ｎｍ”／Ｈが最小限容量であり、したがっ
て、このような吸入圧制御装置でも上記した欠点は解消
されない。Therefore, even if the capacity of the control valve 42 is set to a maximum of 40 ONm"/H, the minimum capacity is 13 to 8 Nm"/H in a normal range ability of -30 to 50. Therefore, such a suction pressure control device However, the above-mentioned drawbacks cannot be resolved.
本発明の目的は、上記した従来技術の欠点を解制御でき
る定値制御方法を提供することにある。SUMMARY OF THE INVENTION An object of the present invention is to provide a constant value control method that can overcome the drawbacks of the prior art described above.
本発明の特徴は、流体の流量の変動量を一定量内に制御
可能な容量の調節弁が全開又は全閉時のみ、少なくとも
該調節弁の容量との合計で流体の流量の全量を制御可能
な容量の調節弁を開閉作動させることで、流体の流量の
全量が大きくなってもそれを一定量に制御できると共に
、流体の流量の変動量を一定量内に制御できるようにし
たことにある。A feature of the present invention is that only when a control valve with a capacity that can control fluctuations in the flow rate of fluid within a certain amount is fully open or fully closed, the entire flow rate of fluid can be controlled at least in total with the capacity of the control valve. By opening and closing a control valve with a certain capacity, it is possible to control the total flow rate of the fluid to a constant amount even if it increases, and also to control the amount of fluctuation in the fluid flow rate to within a constant amount. .
本発明の一実施例を第３図により説明する。An embodiment of the present invention will be explained with reference to FIG.
第３図は、本発明を実施した吸入圧制御装置の系統図で
、なお、第３図で、第２図と同一装置。FIG. 3 is a system diagram of a suction pressure control device embodying the present invention, and FIG. 3 is the same device as FIG. 2.
部品等は同一符号で示し説明を省略する。Parts, etc. are indicated by the same reference numerals and explanations are omitted.
第３図で、導管ｎは、流体の流量の変動量、この場合は
、吸入流量の変動を一定量内に制御可能な容量の調節弁
４が設けられている。導管ｎには、調節弁招をバイパス
し導管ｎ′が連結されている。In FIG. 3, the conduit n is provided with a regulating valve 4 having a capacity capable of controlling the fluctuation amount of the fluid flow rate, in this case, the fluctuation of the suction flow rate, within a certain amount. A conduit n' is connected to the conduit n, bypassing the control valve.
導管ぎには、少なくとも調節弁Ｃの容量との合計で流体
の流量の全量、この場合は、吸入流量の全量を一定量に
制御可能な容量の調節弁ａが設けられている。調節弁葛
は圧力調節計（資）に接続され、また、調節弁舗は、調
節弁招が全開又は全閉時のみ調節弁材を開閉作動させる
機能を有するスイッチ父な介して圧力調節計画に接続さ
れている。The conduit is provided with a control valve a having a capacity that can control the total flow rate of fluid, in this case, the total amount of suction flow rate, to a constant amount in total with at least the capacity of the control valve C. The control valve is connected to a pressure regulator (equipment), and the control valve is connected to the pressure control plan via a switch that has the function of opening and closing the control valve material only when the control valve is fully open or fully closed. It is connected.
今、圧縮機１０の処理風量を１２０ＯＮｍ”／Ｈと仮定
し、また、圧縮機１０の吸入圧を、例えば、１００關Ａ
ｑ士約５０ｍＡｑに制御するとすれば、調節弁ｌの容量
は、レンジアビリティ−を３０〜５０として最小限容量
が数Ｎ ｍ’ ／ Ｈとなることが必要で、また、調節
弁祠の容量は、少なくとも調節弁ぐの容量との合計で１
２００ Ｎｍ”／Ｈ必要となる。Now, assume that the processing air volume of the compressor 10 is 120 ONm"/H, and the suction pressure of the compressor 10 is, for example, 100 ONm"/H.
If the control valve is to be controlled at about 50 mAq, the minimum capacity of the control valve l needs to be several N m'/H with a rangeability of 30 to 50, and the capacity of the control valve shrine is , the total capacity of at least the control valve is 1
200 Nm”/H is required.
まず、流体の流量の全量である吸入流量の全量は次のよ
うにして一定量に制御される。First, the total amount of suction flow rate, which is the total amount of fluid flow rate, is controlled to a constant amount in the following manner.
供給流量が例えば、８０ＯＮｍ”／Ｈから５００８ ｍ
’ ／ Ｈに減量されたとすれば、このままでは、吸入
流量の全量は１２０ＯＮｍ’／Ｈから９０ＯＮｒｒＬ葛
／Ｈに減量されてしまい、その結果、吸入圧力が大幅に
低下する。そこで、まず、圧力調節計（９）により調節
弁部を全開させる。しかし、調節弁葛が全開しても圧縮
機１０の処理風量と比較し吸入流量の全量が未だ不足す
る場合には、圧力調節計間よりスイッチ父に信号を出力
し、スイッチ父により調節弁Ｉは、この場合は開作動さ
せられる。こ入流量の全量は圧縮機１０の処理風量１２
０ＯＮｍ’／Ｈとなる。その後、バイパス流量が７０Ｏ
Ｎｍ”／ＨＨ以上すなわち、吸入流量の全量が１２０Ｏ
Ｎ ｍ” ／ Ｈ以上になると圧力調節計（資）により
調節弁招は閉作動させられ、また、スイッチ父は全開位
置からはずれるため、スイッチ（資）による調節弁偶の
開作動が停止され、調節弁柄は所定弁開度で停止する。For example, if the supply flow rate is from 80ONm”/H to 5008m
If the amount is reduced to '/H, the total suction flow rate will be reduced from 120ONm'/H to 90ONrrL/H, and as a result, the suction pressure will drop significantly. Therefore, first, the control valve section is fully opened using the pressure regulator (9). However, even if the control valve KUD is fully opened, if the total suction flow rate is still insufficient compared to the processing air volume of the compressor 10, a signal is output from between the pressure regulators to the switch father, and the switch father outputs a signal to the control valve I. is operated to open in this case. The total amount of air flow is equal to the processing air volume 12 of the compressor 10.
0ONm'/H. After that, the bypass flow rate is 70O
Nm”/HH or more, that is, the total suction flow rate is 120O
When the pressure exceeds N m"/H, the pressure regulator (equipment) closes the control valve pair, and since the switch father is removed from the fully open position, the switch (equipment) stops the opening operation of the control valve pair. The control valve handle stops at a predetermined valve opening.
このようにしてバイパス流量は７０ＯＮｍ”／Ｈ１すな
わち、吸入流量の全量は１２０ＯＮｍ’ ／ Ｈに制御
される。In this way, the bypass flow rate is controlled to 70 ONm''/H1, that is, the total suction flow rate is controlled to 120 ONm'/H.
逆に供給流量が、例えば、８００ Ｎｍ”／Ｈから１ｌ
１００Ｎ”／Ｈに増量された場合には、上記した操作と
逆操作によりバイパス流量は１１００Ｎ’／Ｈ１すなわ
ち、吸入流量の全量は圧縮機１０の処理風量１２０ＯＮ
ｍ’／Ｈに制御される。Conversely, if the supply flow rate is, for example, from 800 Nm”/H to 1 liter
When the flow rate is increased to 100N'/H, the bypass flow rate is 1100N'/H1 by the above-mentioned operation and reverse operation, that is, the total suction flow rate is the processing air volume of the compressor 10 of 120ON.
m'/H.
また、供給流量の変動により生じる流体の流量の変動量
である吸入流量の変動量は、圧力調節計間により調節弁
葛な慕又は閉作動させ、バイパス流量を供給流量の変動
量と対流させ調節することで、圧縮拶１０の吸入圧力が
所定圧力範囲、例えば、１００５關Ａｑ士約５０ｗＡＱ
となるように制御される。In addition, the amount of fluctuation in the suction flow rate, which is the amount of fluctuation in the fluid flow rate caused by fluctuations in the supply flow rate, can be adjusted by operating the control valve between the pressure regulators to open or close the valve, and by causing the bypass flow rate to convect with the fluctuation amount in the supply flow rate. By doing this, the suction pressure of the compressor 10 is within a predetermined pressure range, for example, 1005 cm and about 50 w AQ.
It is controlled so that
本実施例のような定値制御方法は、供給流量が減量又は
増量されたとしても、それに対応してバイパス流量を増
量又は減量させることで吸入流量の全量を圧縮機の処理
風量に制御できると共に、供給流量の変動量に対応して
バイパス流量を調節することで吸入流量の変動量を圧縮
機の吸入圧が所定圧範囲となるように制御することがで
きる。In the constant value control method as in this embodiment, even if the supply flow rate is decreased or increased, by increasing or decreasing the bypass flow rate accordingly, the total amount of the suction flow rate can be controlled to the processing air volume of the compressor, and By adjusting the bypass flow rate in accordance with the amount of variation in the supply flow rate, it is possible to control the amount of variation in the suction flow rate so that the suction pressure of the compressor falls within a predetermined pressure range.
本発明は、以上説明したように、流体の流量の変動量を
一定量内に制御可能な容量の調節弁が全開又は全閉時の
み、少なくとも該調節弁の容量との合計で流体の流量の
全量を制御可能な容量の調節弁を開閉作動させるという
ことで、流体の流量の全量に影響されることなく流体の
流量の変動量を制御できるので、流体の流量の全量が大
きくなっても、それを一定量に制御できると共に、流体
の流量の変動量を一定量内に制御できる効果がある。As explained above, only when a control valve having a capacity that can control the fluctuation amount of the fluid flow rate within a certain amount is fully open or fully closed, the flow rate of the fluid is reduced at least in total with the capacity of the control valve. By opening and closing a control valve with a capacity that can control the total flow rate, it is possible to control the amount of fluctuation in the fluid flow rate without being affected by the total flow rate of the fluid, so even if the total flow rate of the fluid increases, This has the effect of being able to control it to a constant amount and also controlling the amount of fluctuation in the flow rate of the fluid to within a constant amount.
第１図、第２図は、従来の定値制御方法を実施した吸入
圧制御装置の系統図、第３図は、本発明を実施した吸入
圧制御装置の一実施例を示す系統図である。
２２、２３’・・・・・・導管、加・・面圧力調節計、
葛、４４・・・調節弁、刃・・・・・・スイッテ1 and 2 are system diagrams of a suction pressure control device implementing a conventional fixed value control method, and FIG. 3 is a system diagram showing an embodiment of a suction pressure control device implementing the present invention. 22, 23'... Conduit, pressure controller,
Kudzu, 44...Control valve, Blade...Suite
Claims (1)
量の変動量を一定量内に制御する方法において、前記流
体の流量の変動量を一定量内に制御可能な容量の調節弁
が全開又は全閉時のみ、少なくとも該調節弁の容量との
合計で前記流体の流量の全量を一定量に制御可能な容量
の調節弁を開閉作動させることを特徴とする定値制御方
法。1. In a method for heating the entire flow rate of a fluid by a certain amount and controlling the amount of variation in the flow rate of the fluid within a certain amount, a regulating valve having a capacity that can control the amount of variation in the flow rate of the fluid to be within a certain amount. A constant value control method, characterized in that only when the control valve is fully open or fully closed, a control valve having a capacity that can control the total flow rate of the fluid to a constant amount at least in total with the capacity of the control valve is opened and closed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10205282A JPS58219617A (en) | 1982-06-16 | 1982-06-16 | Constant value controlling method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10205282A JPS58219617A (en) | 1982-06-16 | 1982-06-16 | Constant value controlling method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS58219617A true JPS58219617A (en) | 1983-12-21 |
| JPH0529925B2 JPH0529925B2 (en) | 1993-05-06 |
Family
ID=14316990
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10205282A Granted JPS58219617A (en) | 1982-06-16 | 1982-06-16 | Constant value controlling method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58219617A (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5299969A (en) * | 1976-02-18 | 1977-08-22 | Hitachi Ltd | Condensation desalting apparatus |
| JPS56100701U (en) * | 1979-12-27 | 1981-08-08 |
-
1982
- 1982-06-16 JP JP10205282A patent/JPS58219617A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5299969A (en) * | 1976-02-18 | 1977-08-22 | Hitachi Ltd | Condensation desalting apparatus |
| JPS56100701U (en) * | 1979-12-27 | 1981-08-08 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0529925B2 (en) | 1993-05-06 |
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