JP7532012B2 - Pressure control method and pressure control device for gas pressure transmission equipment - Google Patents

Description

The present invention relates to a pressure control method and a pressure control device for a gas compression facility when the gas pressure at the destination of the gas compressed by a compressor of the gas compression facility fluctuates.

It is generally known that gas compression equipment must perform pressure control so that the supply gas pressure does not change due to fluctuations in the load at the destination, and must maintain a constant supply gas pressure from the destination to the destination of use . There are many prior art control methods for this purpose, such as inverter control of the compressor (see Patent Document 1) and control of the number of compressors (see Patent Document 2).

As control methods for these, various proposals have been made to save energy and maintain the process pressure of the compressed gas at the target point of pressure control in the gas compression piping within the control range, such as control of the number of compressors using a combination pattern according to the detection results of the gas supply flow rate from the gas compression piping to the destination (see Patent Document 3), control of calculating the pipeline resistance of the gas supply piping to the destination and changing the target set value of the pressure control based on the result (see Patent Document 4), and control of calculating the pressure loss in the gas compression piping from the difference between the discharge pressure of the compressor and the process pressure of the compressed gas at the target point of pressure control in the gas compression piping and changing the target set value of the pressure control based on the result (see Patent Document 5).

JP 2000-320467 A Japanese Unexamined Patent Publication No. 58-127216 Japanese Patent Application Publication No. 06-249151 Japanese Patent Application Publication No. 61-201900 JP 2009-013961 A

In the pressure control of a compressor, when the process pressure of the compressed gas at the target point of the pressure control changes and a difference occurs between the process pressure and the target set value of the pressure control, the motor inverter and the discharge valve opening are controlled by a well-known PID (proportional-integral-derivative) control to increase or decrease the compressor discharge flow rate and raise or lower the discharge pressure to the gas pressure transmission pipe, thereby controlling the process pressure . For example, Fig. 6 shows an example of a conventional gas pressure transmission facility, which includes a compressor (CMP) 2 and a discharge valve 3 in series at one end of a gas pressure transmission pipe 1, and a pressure gauge 4 at the pressure control target point at the other end of the gas pressure transmission pipe 1. A pressure indicating controller ( PIC) 5 controls the opening of the discharge valve 3 and controls the operation of the drive motor of the compressor 2 via an inverter (INV) 6 so that the process pressure P1 of the compressed gas measured by the pressure gauge 4 approaches a separately given target set value (target pressure) SP of the pressure control . This gas pressure transmission equipment also has a flow meter 7 and a discharge valve 8 in series on the other end of the gas pressure transmission piping 1, and a flow indicator controller (FIC) 9 controls the opening of the discharge valve 8 based on the gas flow rate measured by the flow meter 7 to adjust the supply gas flow rate from the gas pressure transmission piping 1 to a mixed gas line (MGL) 10, which is the destination of the gas pressure transmission, and measures the gas pressure P2 in the mixed gas line 10 with a pressure meter 11, and supplies the mixed gas from the mixed gas line 10 to each user (USR) 12, such as a factory.

6, in the control described in Patent Document 4, when the flow rate of the compressed gas to the mixed gas line 10, which is the destination of the compressed gas, is increased, the process pressure P1 of the compressed gas at the pressure control target point decreases, and the process pressure P1 is maintained at the target set value SP by increasing the discharge flow rate of the compressor 2. Also, when the flow rate of the compressed gas to the mixed gas line 10, which is the destination of the compressed gas, is decreased, the process pressure P1 of the compressed gas at the pressure control target point increases, and the discharge flow rate of the compressor 2 is decreased to maintain the process pressure P1 at the target set value SP.

However, when the gas pressure at the pumping destination fluctuates, the target set value of the pressure control of the compressor must always be set to a value higher than the gas pressure at the pumping destination, taking into consideration the fluctuation of the gas pressure at the pumping destination. This is also true of the control described in Patent Document 5, which calculates the pressure loss from the difference between the compressor's discharge pressure and the process pressure of the pumped gas at the pressure control target point to change the target set value of the pressure control, and the basic target set value must always be set to a value higher than the gas pressure at the pumping destination. Therefore, even if the gas pressure at the pumping destination is decreasing, the compressor is pressurizing the gas more than necessary, and it cannot be said that appropriate energy-saving operation is being performed. In addition, since the compressor increases or decreases the discharge flow rate after the process pressure at the pressure control target point decreases or increases by increasing or decreasing the gas flow rate to the pumping destination, there is a problem that pressure control takes time and response is poor.

In the control described in Patent Document 4, in which the pressure loss is calculated in accordance with the detection results of the gas flow rate to the pumping destination and the target set value of the pressure control is changed, the process pressure at the target point of the pressure control is minimized. However, since the detection of the gas flow rate to the pumping destination is incorporated into the pressure control, there is a problem in that it is costly to implement.

Furthermore, the control methods described in Patent Documents 4 and 5 both have the problem that the calculation formula for pressure loss must be reviewed each time the piping configuration is changed.

Therefore, an object of the present invention is to provide a pressure control method and pressure control device for a gas pressure transmission equipment which advantageously solves the problems of the conventional technology, can achieve energy savings even when the gas pressure of the destination of the compressed gas fluctuates in pressure control of the gas pressure transmission equipment , and can improve the responsiveness of pressure control .

The pressure control method for a gas pressure-transporting facility of the present invention, which achieves the above object, comprises:
When the gas pressure in a gas line that supplies gas to a destination fluctuates, pressure control is performed in a gas pressure transmission facility that includes a compressor and a discharge valve, which pressure-transmits compressed gas through a gas pressure transmission pipe to the gas line as a destination and mixes the compressed gas into the gas pressure transmission pipe,
A target set value serving as a target pressure for pressure control is changed in response to fluctuations in the gas pressure of the destination of compressed gas delivery,
the target set value is based on a value obtained by adding an additive set value, which is a predetermined positive fixed value, to the gas pressure at the pumping destination to obtain a basic set value, and adding to the basic set value an additional set value obtained by multiplying the difference between the basic set value and the process pressure of the pumped gas at a target point of pressure control in the gas pumping piping by a multiplication coefficient value, which is a predetermined positive fixed value;
controlling operation of a drive motor of the compressor via an inverter so as to bring the process pressure close to the target set value, and controlling an opening degree of the discharge valve that discharges the gas compressed by the compressor to the gas pressure feed pipe;
It is characterized by:

In addition, the present invention provides a pressure control device for a gas pressure-transfer facility that achieves the above object,
A pressure control device for controlling pressure in a gas pressure transmission facility including a compressor and a discharge valve, which pressure-transmits compressed gas through a gas pressure transmission pipe to a gas line that supplies gas to a destination and mixes the compressed gas therein when the gas pressure in the gas line fluctuates , comprising:
a gas pressure detection means for detecting a gas pressure at the destination;
a process pressure detection means for detecting a process pressure of the pressurized gas at a target point of pressure control in the gas pressure feed pipe;
a target set value changing means for changing a target set value as a target pressure for pressure control in response to fluctuations in the gas pressure of the destination detected by the destination gas pressure detecting means, the target set value being based on a value obtained by adding an additive set value, which is a predetermined positive fixed value, to the gas pressure of the destination to obtain a basic set value, and adding an additional set value, which is obtained by multiplying the difference between the basic set value and the process pressure of the gas of the destination at the target point of pressure control detected by the process pressure detecting means, by a multiplication coefficient value, which is a predetermined positive fixed value, to the basic set value;
a pressure control means for controlling the operation of a drive motor of the compressor via an inverter so as to bring the process pressure close to the target set value, and for controlling an aperture of the discharge valve for discharging the gas compressed by the compressor to the gas pressure transport pipe;
The present invention is characterized by comprising:

The addition of an additive set value, which is a predetermined positive fixed value, to the gas pressure at the destination to obtain a basic set value, and the addition of an additional set value obtained by multiplying the difference between the basic set value and the process pressure of the compressed gas at the target point of pressure control in the gas compression pipe by a multiplication coefficient value, which is a predetermined positive fixed value, to the basic set value is performed by performing the calculation of the following equation (1).
SP = (P2+α)+(((P2+α)-P1)×β)...(1)
Here,
SP: Target set value for pressure control P1: Process pressure of the compressed gas at the target point of pressure control in the gas compression pipe P2: Gas pressure at the destination P2 + α: Basic set value ((P2 + α) - P1) x β: Additional set value α: Additional set value (variable positive fixed value)
β: Multiplication coefficient value (variable positive fixed value)
It is.

According to the pressure control method and pressure control device for gas pressure transmission equipment of the present invention, in pressure control of a gas pressure transmission equipment having a compressor and a discharge valve that pressure -transfers compressed gas to a gas line that supplies gas to a destination of use through a gas pressure transmission piping and mixes it with the destination, when the gas pressure at the destination of the pressure transmission fluctuates, a basic setting value for pressure control is set to a value obtained by always adding an additive setting value α, which is a predetermined positive fixed value, to the gas pressure at the destination of the pressure transmission in accordance with the fluctuation of the gas pressure at the destination of the pressure transmission, and a target setting value for pressure control is constantly changed based on the basic setting value, and operation of the drive motor of the compressor is controlled via an inverter so that the process pressure of the compressed gas at the target point of the pressure control in the gas pressure transmission piping approaches the changed target setting value, and pressure control is performed to control the opening of the discharge valve that discharges the gas compressed by the compressor into the gas pressure transmission piping, thereby minimizing the increase in pressure of the compressed gas by the compressor, thereby achieving energy savings.

In addition, an additional setting value is obtained by multiplying the difference between the value obtained by adding a predetermined additional setting value α to the gas pressure at the destination and the process pressure of the compressed gas at the target point of pressure control in the gas compression pipe, which is a predetermined positive fixed value, by multiplying the difference between the process pressure of the compressed gas at the target point of pressure control in the gas compression pipe and the target setting value, and by changing the target setting value of the pressure control based on the value obtained by adding the additional setting value to the basic setting value, the difference between the process pressure of the compressed gas at the target point of pressure control and the target setting value temporarily increases, and pressure control in the gas compression pipe is performed to bring the process pressure closer to the changed target setting value, thereby improving the responsiveness of the pressure control .

In this control, when the process pressure of the compressed gas at the target point of pressure control becomes greater than the target set value, the compressor can reduce the pressure increase of the compressed gas more quickly, which also has the effect of saving energy. In addition , since there is no need to install a gas flow meter and incorporate the compressed gas flow rate to the destination into the pressure control, the gas compression equipment can be made less expensive, and even if the piping configuration is changed, there is no need to review the calculation formula for pressure loss each time.

For example, in the case of a gas pumping system in which a compressor compresses the gas in a gas holder that collects flammable by-product gas generated during blowing in a batch-wise steelmaking process, and pumps the gas to a mixed gas line as the pumping destination , improving the responsiveness of the compressor enables the compressor to deliver more flammable by-product gas to the mixed gas line more quickly even when the holder level of the gas holder is high and the gas holder is unable to collect the flammable by-product gas, which is expected to have the effect of reducing the amount of flammable by-product gas emitted.

In order to prevent hunting in the control, a dead band may be set for the change in the target setting value, and upper and lower limits may be set for the change in the target setting value to prevent the value from exceeding the limits of the equipment capacity.

1 is a schematic diagram showing a configuration of a gas compression facility including an embodiment of a compressor pressure control device of the present invention, to which an embodiment of a compressor pressure control method of the present invention is applied. FIG. 2 is a block diagram showing a procedure of a pressure control method of the embodiment in the pressure control device of the embodiment. 5 is a characteristic diagram showing a dead zone and upper and lower limits of a change in a target set value over time in the pressure control method according to the embodiment. FIG. 1 is a trend graph showing changes over time in the compressor discharge flow rate, the target set value of pressure control, the process pressure at the target point of pressure control, and the mixed gas pressure in a comparative example for reference to the pressure control method of the above embodiment. 11 is a trend graph showing changes over time in the compressor discharge flow rate, the target set value of pressure control, the process pressure at the target point of pressure control, and the destination gas pressure in the example of the pressure control method of the embodiment. 1 is a schematic diagram showing a configuration example of a gas pressure-transfer facility including a conventional compressor pressure control device.

The following describes in detail an embodiment of the present invention with reference to the drawings. Here, FIG. 1 is a schematic diagram showing the configuration of an embodiment of a compressor pressure control device of the present invention to which an embodiment of a compressor pressure control method of the present invention is applied, and in FIG. 1, parts similar to those in FIG. 6 are indicated by the same reference numerals.

That is, this gas pressure transfer facility equipped with the compressor pressure control device of this embodiment is equipped with a compressor (CMP) 2 and a discharge valve 3 in series at one end of a gas pressure transfer pipe 1, and is equipped with a pressure gauge 4 as process pressure detection means at a target point of pressure control at the other end of the gas pressure transfer pipe 1, and a pressure indicating regulator (PIC) 5 as pressure control means controls the opening of the discharge valve 3 so that the process pressure P1 of the compressed gas measured by the pressure gauge 4 approaches a separately given target set value (target pressure) SP for pressure control, and also controls the operation of the drive motor of the compressor 2 via an inverter (INV) 6 . This gas pressure transmission equipment also has a flow meter 7 and a discharge valve 8 in series on the other end of the gas pressure transmission piping 1, and a flow indicator controller (FIC) 9 controls the opening of the discharge valve 8 based on the gas flow rate measured by the flow meter 7 to adjust the flow rate of the pressure gas transmitted from the gas pressure transmission piping 1 to a mixed gas line (MGL) 10 which is the destination of the gas transmission. The gas pressure P2 in the mixed gas line 10 is measured by a pressure gauge 11 which serves as a destination gas pressure detection means, and the mixed gas is supplied from the mixed gas line 10 to each user (USR) 12, such as a factory.

Furthermore, the pressure control device of this embodiment is equipped with a normal computer 13 as a target set value changing means, and this computer 13 is a normal one having a central processing unit (CPU), storage means such as a memory and a hard disk drive device, input/output devices such as a keyboard and a display device, and an input/output interface connecting these input/output devices to the CPU, and basically operates based on a pre-given program, and receives as input the process pressure P1 measured by the pressure gauge 4 and the destination (pressure-feed) gas pressure P2 measured by the pressure gauge 11, as well as an additive set value (a settable, positive fixed value) α and a multiplication coefficient value (a settable, positive fixed value) β, and calculates a pressure control target set value SP according to the following equation (1) as shown in FIG. 1 based on the process pressure P1, destination gas pressure P2, additive set value α, and multiplication coefficient value β, and changes the pressure control target set value SP to be given to the pressure indicating regulator 5 to the value determined by this calculation.

ここに、
ＳＰ：圧力制御の目標設定値（ｋＰａ）
Ｐ１：ガス圧送配管１での圧力制御の目標地点の圧送ガスのプロセス圧力（ｋＰａ）
Ｐ２：混合ガスライン１０（圧送先）のガス圧力（ｋＰａ）
Ｐ２＋α：基本設定値
（（Ｐ２＋α）－Ｐ１）×β：付加設定値
α：加算設定値（設定可変の正の固定値）（ｋＰａ）
β：乗算係数値（設定可変の正の固定値）
である。

Here,
SP: Target set value for pressure control (kPa)
P1: process pressure (kPa) of the compressed gas at the target point of pressure control in the gas compression pipe 1
P2: Gas pressure (kPa) of mixed gas line 10 (destination)
P2 + α: Basic setting value ((P2 + α) - P1) × β: Additional setting value α: Additional setting value (variable positive fixed value) (kPa)
β: Multiplication coefficient value (variable positive fixed value)
It is.

In the pressure control of the compressor 2 of the pumping equipment shown in Fig. 1, when the gas pressure P2 of the mixed gas line 10 fluctuates, the pressure control device of this embodiment uses a basic set value (P2 + α), which is a value obtained by always adding an additional set value α to the gas pressure P2 of the mixed gas line 10, as the target set value SP of the pressure control in response to the fluctuation of the gas pressure P2, and constantly changes the target set value SP, thereby minimizing the increase in pressure of the gas in the gas pumping pipe 1 by the compressor 2 and achieving energy savings. Note that the additional set value α is preferably variable so that it can be adjusted during operation, and is preferably set to, for example, α ≧ 0.

Furthermore, according to the pressure control device of this embodiment, the additional set value (((P2+α)-P1)×β) which is the difference ((P2+α)-P1) between the basic set value (P2+α) obtained by adding the additive set value α to the gas pressure P2 in the mixed gas line 10 and the process pressure P1 at the target point of pressure control in the gas pressure delivery pipe 1 and the multiplication coefficient value β is used as the target set value SP of pressure control in addition to the basic set value (P2+α), thereby increasing the difference between the process pressure P1 at the target point of pressure control in the gas pressure delivery pipe 1 and the target set value SP of pressure control , thereby improving the responsiveness of pressure control. Note that the value of the multiplication coefficient value β is preferably variable so that it can be adjusted during operation, and it is preferable to be able to set, for example, β≧0.

FIG. 2 is a block diagram showing the procedure of the pressure control method of the above embodiment in the pressure control device of the above embodiment. The pressure control device of this embodiment further includes an additional set value ((P2+α)-P1)×β) which is a value obtained by multiplying the difference between a basic set value (P2+α) obtained by adding α to the gas pressure P2 in the mixed gas line 10 and the process pressure P1 at the target point of pressure control in the gas pressure transport piping 1 by a multiplication coefficient value β in order to prevent equipment failures of the compressor 2, inverter 6, etc., and a filter for a dead band (non-additive upper and lower limit set value) is provided in consideration of preventing control hunting due to the instrument sensitivity of the pressure gauges 4, 11 and small fluctuations in the process pressure P1. Also, a filter for an additive upper and lower limit set value is provided so that the target set value does not become a pressure control target set value that exceeds the limit of the equipment capacity of the compressor 2, etc., and in addition, a filter for an upper and lower limit set value of the pressure control target set value is provided for the final output pressure control target set value SP.

Figure 3 is a characteristic diagram showing the dead zone and upper and lower limits of the change in the target set value SP over time shown on the horizontal axis in the pressure control method of the above embodiment, and after passing through the filter, there is a dead zone between the non-additive upper and lower limit set values, and the numerical value becomes 0 regardless of the change before passing through the filter. Also, after passing through the filter, it becomes constant above and below the additive upper and lower limit set values, and the numerical value becomes the additive upper and lower limit set values regardless of the change before passing through the filter.

Figures 4 and 5 show trend graphs showing the trends of changes in the discharge flow rate Q of compressor 2 of the pumping equipment of Figure 1, the target set value SP of pressure control , the process pressure P1 at the target point of pressure control, and the gas pressure P2 of the mixed gas line 10 into which the gas is mixed, which are actually controlled using a comparative pressure control method for reference to the pressure control method of the above embodiment, and the pressure control method of the above embodiment, respectively .

4 is a trend graph of a comparative example in which α=1.5 and β=0 are set. The timing when the gas flow rate to the mixed gas line 10 of the mixing destination is increased by +20 kNm ³ /H is 0 seconds on the horizontal axis of the trend graph. As the gas flow rate to the mixing destination increases, the process pressure P1 at the target point of the pressure control starts to decrease, and a difference occurs between the target set value SP of the pressure control and the process pressure P1 at the target point of the pressure control, which shows that the discharge flow rate Q of the compressor 2 is increased by the pressure control . In the case of this comparative example, it took 184 seconds for the discharge flow rate Q of the compressor 2 to increase from 80 kNm ³ /H to 100 kNm ³ /H. It can also be seen that the target set value SP of the pressure control is always 1.5 kPa higher than the gas pressure P2 of the mixing destination. The value of α must be set so that, when the gas flow rate to the destination is increased, the gas pressure P2 at the destination is lower than the reduced value of the process pressure P1 at the target point of pressure control.The value of α is preferably as small as possible.

5 is a trend graph of an embodiment in which α=1.5 and β=1.5 are set. The timing when the gas flow rate to the mixed gas line 10 of the mixing destination is increased by +20 kNm ³ /H is 0 seconds on the horizontal axis of the trend graph. As the gas flow rate to the mixing destination increases, the process pressure P1 of the target point of the pressure control starts to decrease, and the target set value SP of the pressure control is set to the value obtained by multiplying the difference between the basic set value (P2+α) obtained by adding α to the gas pressure P2 of the mixing destination and the process pressure P1 of the target point of the pressure control by the multiplication coefficient value β. The target set value SP of the pressure control temporarily increases, and it can be seen that the difference between the target set value SP of the pressure control and the process pressure P1 of the target point of the pressure control becomes larger than that of the trend graph of FIG. 4. In this embodiment, the time required for the discharge flow rate Q of the compressor 2 to increase from ⁸⁰ kNm3/H to 100 ^kNm3 /H through pressure control was 138 seconds, which is 46 seconds faster than the trend graph of Figure 4. As can be seen from the gradient of the change in the discharge flow rate Q of the compressor 2, good pressure control results with improved responsiveness of the compressor 2 were obtained.

Also, according to this embodiment, when there is not much difference between the target set value SP of the pressure control and the process pressure P1 at the target point of the pressure control , it can be seen that the target set value SP of the pressure control is always 1.5 kPa higher than the gas pressure P2 at the mixing destination. The value of α must be set in consideration of the fact that, when the gas flow rate to the mixing destination is increased, the gas pressure P2 at the mixing destination becomes lower than the reduced value of the process pressure P1 at the target point of the pressure control , and the value is preferably as small as possible. For example, if the process pressure P1 at the target point of the pressure control decreases by a maximum of 1.4 kPa when the gas flow rate to the mixing destination is increased during operation, it is preferable to set the value of 1.6 ≧ α > 1.4. The value of β is preferably large in order to improve the responsiveness of the compressor 2, but it must be set in consideration of the equipment specifications and controllability (overshoot, etc.). For example, if the inverter speed change rate reaches its upper limit or the compressor vibration increases when β = 1.6, it is preferable to set the value of 1.6 > β ≧ 1.4.

Although the above has been explained based on the illustrated example, the present invention is not limited to the above example and can be modified as necessary within the scope of the claims. For example, in the pressure control method of the above embodiment, when there are multiple compressors 2, the pressure control target set value SP obtained as described above can be used as a master pressure control target set value, which can be distributed to the control of each individual compressor 2. In addition, the destination of the gas compressed by the compressor 2 is not limited to the mixed gas line 10 that supplies mixed gas to a user 12 such as a factory, but can be other types of equipment.

Thus, according to the pressure control method and pressure control device for gas pressure transmission equipment of the present invention, energy can be saved in pressure control of the gas pressure transmission equipment even when the gas pressure of the destination of the compressed gas fluctuates, and the responsiveness of the pressure control can be improved.

1 Gas pressure pipe 2 Compressor (CMP)
3, 8 Discharge valve 4, 11 Pressure gauge 5 Pressure indicating controller (PIC)
6 Inverter (INV)
7 Flowmeter 9 Flow rate indicating controller (FIC)
10 Mixed gas line (MGL)
12 Where to use (USR)
13 Computer SP Target set value of pressure control P1 Process pressure of compressed gas at the target point of pressure control P2 Gas pressure of mixed gas line (destination of compressed gas) α Addition set value β Multiplication coefficient value

Claims (5)

When the gas pressure in a gas line that supplies gas to a user fluctuates, pressure control is performed in a gas pressure transmission facility that includes a compressor and a discharge valve, which pressure-transmits compressed gas through a gas pressure transmission pipe to the gas line as a destination and mixes the compressed gas therein,
A target set value serving as a target pressure for pressure control is changed in response to fluctuations in the gas pressure of the destination of compressed gas delivery,
the target set value is based on a value obtained by adding an additive set value, which is a predetermined positive fixed value, to the gas pressure at the pumping destination to obtain a basic set value, and adding to the basic set value an additional set value obtained by multiplying the difference between the basic set value and the process pressure of the pumped gas at a target point of pressure control in the gas pumping piping by a multiplication coefficient value, which is a predetermined positive fixed value;
controlling operation of a drive motor of the compressor via an inverter so as to bring the process pressure close to the target set value, and controlling an opening degree of the discharge valve that discharges the gas compressed by the compressor to the gas pressure feed pipe;
A pressure control method for a gas pressure transmission facility , comprising: 2. The pressure control method for a gas pressure transmission facility according to claim 1, wherein the step of adding an additive setting value, which is a predetermined positive fixed value, to the gas pressure at the pressure destination to obtain a basic setting value, and adding an additional setting value obtained by multiplying the difference between the basic setting value and the process pressure of the pressure transmission gas at a target point of pressure control in the gas pressure transmission piping by a multiplication coefficient value, which is a predetermined positive fixed value, to the basic setting value, is performed by performing a calculation according to the following equation (1).
SP = (P2+α)+(((P2+α)-P1)×β)...(1)
Here,
SP: Target set value for pressure control P1: Process pressure of the compressed gas at the target point of pressure control in the gas compression pipe P2: Gas pressure at the destination P2 + α: Basic set value ((P2 + α) - P1) x β: Additional set value α: Additional set value (variable positive fixed value)
β: Multiplication coefficient value (variable positive fixed value)
It is. 3. The pressure control method for a gas pressure-transport facility according to claim 1, further comprising providing a dead zone for changing the target set value. 4. The pressure control method for a gas pressure-transport facility according to claim 1, further comprising setting upper and lower limits for changing the target set value. A pressure control device for controlling pressure in a gas pressure transmission facility including a compressor and a discharge valve, which pressure-transmits compressed gas through a gas pressure transmission pipe to a gas line that supplies gas to a destination and mixes the compressed gas therein when the gas pressure in the gas line fluctuates , comprising:
a gas pressure detection means for detecting a gas pressure at the destination;
a process pressure detection means for detecting a process pressure of the pressurized gas at a target point of pressure control in the gas pressure feed pipe;
a target set value changing means for changing a target set value as a target pressure for pressure control in response to fluctuations in the gas pressure of the destination detected by the destination gas pressure detecting means, the target set value being based on a value obtained by adding an additive set value, which is a predetermined positive fixed value, to the gas pressure of the destination to obtain a basic set value, and adding an additional set value, which is obtained by multiplying the difference between the basic set value and the process pressure of the gas of the destination at the target point of pressure control detected by the process pressure detecting means, by a multiplication coefficient value, which is a predetermined positive fixed value, to the basic set value;
a pressure control means for controlling the operation of a drive motor of the compressor via an inverter so as to bring the process pressure close to the target set value, and for controlling an aperture of the discharge valve for discharging the gas compressed by the compressor to the gas pressure transport pipe;
A pressure control device for a gas pressure supply facility, comprising:

Images