JPH04220701A - Fluid control system - Google Patents

Abstract

PURPOSE:To offer the fluid control system which gives a controlled variable as set even when used in an open loop by improving the nonlinearity of a proportional control valve. CONSTITUTION:This system is equipped with a hydraulic pressure line 10 as a system to be controlled, a pressure control valve 20 as the proportional control valve which controls the hydraulic pressure of the hydraulic pressure line 10, a pressure measuring means 30 which measures the hydraulic pressure of the hydraulic pressure line 10, a flow rate measuring means 40 which measures the flow rate of the hydraulic pressure line 10, and a controller 50 which controls the valve opening/closing operation of said pressure control valve 20. This controller 50 has an EEPROM where a static characteristic showing the relation of a controlled variable to an operation signal is stored and held, and a ROM stored with a program wherein a procedure for measuring the static characteristic as to the pressure control valve is described and a program wherein a procedure for generating the operation signal for obtaining the controlled variable corresponding to a target value is described, and a CPU which executes those programs.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a system for controlling the pressure and flow rate of a fluid using an electromagnetic proportional control valve, and in particular, the linearity of the input/output relationship of the proportional control valve.
A fluid control system with improved linearity of a controlled variable relative to a target value, a controller used therein, and
This article relates to a linearization method for proportional control valves.

0002

2. Description of the Related Art Fluid control systems use electromagnetic proportional control valves to control the pressure and flow rate of fluid. An example of a proportional control valve is a pilot relief valve, which is used to control hydraulic pressure.

[0003] This pilot relief valve consists of, for example, a hydraulic mechanism part and a DC solenoid part. The DC solenoid portion includes a coil, a fixed iron core, and a movable iron core, and is configured such that the movable iron core is attracted to the fixed iron core by an electromagnetic force generated in response to a DC current supplied to the coil. On the other hand, the hydraulic mechanism portion includes a valve that operates in conjunction with the movable iron core. With this configuration, the pilot relief valve can change the opening degree of the valve depending on the magnitude of the DC current supplied to the coil.
In a controlled system that uses oil pressure, it is possible to obtain oil pressure that corresponds to the magnitude of direct current.

Further, such a pilot relief valve can handle a larger flow rate by combining with another valve, for example, a balance piston type main valve.

[0005]

This type of proportional control valve has a problem in that the relationship between input and output is nonlinear, and the actual output does not correspond linearly to the target value. Moreover, in the case of a pressure control valve, this nonlinearity has a complicated problem in that it varies depending on the flow rate. FIG. 12 shows the relationship between the input (x-axis) and the output (y-axis) when the balanced piston type main valve is pilot operated by the pilot relief valve. As is clear from the figure, the input/output relationship is nonlinear, and the relationship takes on different curves depending on the flow rate.

When trying to obtain a target pressure in a hydraulic line using such a proportional control valve, even if the target pressure is set as a target value, it is impossible to obtain the desired pressure due to the nonlinearity of the proportional control valve and the flow rate. Due to variations, the actual pressure obtained will differ from the set point. In response, we measure the pressure in the hydraulic line and feed it back.
By determining the deviation from the target value and controlling the deviation to zero, the desired pressure can finally be obtained. However, in the case of a proportional control valve used in an open loop without feedback control, the difference between the target value and the actual pressure cannot be corrected automatically and becomes an error, or must be corrected manually. I have no choice but to.

Conventionally, regarding the problem of nonlinearity when using this type of proportional control valve in an open loop,
No special consideration was given. However, in recent years, in order to realize highly accurate control in hydraulic control systems and the like, there has been a demand for improvement in the nonlinearity of this type of proportional control valve.

[0008] A first object of the present invention is to provide a fluid control system that improves the nonlinearity of a proportional control valve and can obtain a controlled variable according to a set value even when used in an open loop.

A second object of the present invention is to provide a controller that improves the nonlinearity of a proportional control valve so that a controlled amount according to a set value can be obtained even when used in an open loop. It's about doing.

Furthermore, a third object of the present invention is to provide a linearization method for a proportional control valve that improves the nonlinearity of the proportional control valve so that the controlled variable according to the set value can be obtained even when used in an open loop. It is about providing.

[0011]

[Means for Solving the Problems] In order to achieve the above first object, according to a first aspect of the present invention, a fluid line to be controlled and a fluid line are controlled according to an operation signal corresponding to a target value. a proportional control valve for controlling to a target state; a first measuring means for measuring a parameter indicating the state of the fluid in the fluid line; and operating signals and control states of the fluid at a plurality of points in the operating range of the proportional control valve. storage means for storing the results of pre-measurement of the previously specified parameters, and a target value according to the value of the parameter representing the state of the fluid line measured by the first measuring means;
and an operation signal generation means for applying the control state of the fluid stored in the storage means to obtain a corresponding operation signal, and controlling the fluid line by driving the proportional control valve using the operation signal. A fluid control system is provided.

The fluid control system of the present invention includes a second measuring means for measuring the control state of the fluid line to be controlled, and generating operation signals at multiple points in the operating range of the proportional control valve under specified parameters. and a third measuring means for driving the proportional control valve, taking in the corresponding measurement result of the second measuring means, and measuring the correspondence between the operation signal and the control state. be able to.

[0013] In order to achieve the above second object, according to a second aspect of the present invention, a controller is provided which controls a proportional control valve provided in a fluid line by outputting an operation signal corresponding to a target value. and a memory for storing the results of pre-measurement of the correspondence between the operation signal and the fluid control state at a plurality of points in the operating range of the proportional control valve with respect to a pre-designated parameter indicating the state of the fluid in the fluid line. and an operation signal for applying the target value to the fluid control state stored in the storage means according to the value of a parameter representing the state of the fluid line given from the outside to obtain a corresponding operation signal. There is provided a fluid control controller characterized in that the controller includes a generating means and controls a proportional control valve using the operation signal.

The controller of the present invention generates operation signals at multiple points in the operating range of the proportional control valve under specified parameters to drive the proportional control valve, and also generates operation signals at a plurality of points in the operating range of the proportional control valve under specified parameters, and also generates operation signals at a plurality of points in the operating range of the proportional control valve based on designated parameters, and also generates operation signals at a plurality of points in the operating range of the proportional control valve based on specified parameters, and drives the proportional control valve. It is possible to further include a measuring means for taking in the above-mentioned operation signal from the outside and measuring the correspondence between the above-mentioned operation signal and the control state.

Furthermore, in order to achieve the third objective,
According to the third aspect of the present invention, regarding a proportional control valve that controls a fluid to a target state in response to an operation signal corresponding to a target value, the operation signal and the fluid at a plurality of points in the operating range of the proportional control valve Based on the results of measuring the correspondence with the control state in advance, the target value is applied to the control state of the fluid, a corresponding operation signal is obtained, and the proportional control valve is controlled by this operation signal. A proportional control valve linearization scheme is provided.

[0016]

[Operation] The present invention provides a proportional control valve for controlling the fluid to a desired state in accordance with an operation signal corresponding to a target value in a fluid line to be controlled such as a hydraulic line, and the opening of the proportional control valve is can be applied to a system that sets the condition of a fluid line, e.g., fluid pressure, to a desired value by controlling the condition.

When controlling the fluid, the correspondence between the operation signals at multiple points in the operating range of the proportional control valve and the fluid control state, for example, the fluid pressure, is determined by a parameter indicating the fluid state of a prespecified fluid line. (For example, when controlling fluid pressure such as oil pressure, flow rate) is previously measured and stored in the storage means. Then, when controlling the fluid, the above parameters are measured by the measuring means. In addition, the target value is set by the operation signal generation means.
In accordance with the value of a parameter representing the state of the fluid line measured by the measuring means, it is applied to the fluid control state stored in the storage means to obtain a corresponding operation signal. This operation signal can drive the proportional control valve to control the fluid line. Therefore, since the operation signal is obtained inversely from the fluid control state corresponding to the target value, even if the operation signal and the fluid control state (control amount) are nonlinear, they appear linear from the target value. Therefore,
Even in an open loop, linear control is possible. Moreover, since a correspondence relationship between the operation signal and the fluid control state is required for parameters indicating the control state of the fluid specified in advance, such as flow rate, even if there are fluctuations in parameters such as flow rate, non-linearity can be improved.

Note that the number of measurement points that are measured in advance and stored in the storage means is limited. Therefore, during actual control, the data at those measurement points may be subjected to, for example, linear interpolation to obtain the desired amount.

Further, in the fluid control system of the present invention, the system may itself measure the correspondence between the operation signal stored in the storage means and the control state. That is, the measuring means measures the control state of the fluid line to be controlled, generates operation signals at multiple points in the operating range of the proportional control valve under specified parameters, and drives the proportional control valve. , the corresponding measurement result of the measuring means may be taken in to measure the correspondence between the operation signal and the control state.

[0020]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a system diagram showing the configuration of one embodiment of the fluid control system of the present invention.

The fluid control system of this embodiment includes a hydraulic line 10 that is a controlled system, a pressure control valve 20 that is a proportional control valve that controls the hydraulic pressure of this hydraulic line 10, and a hydraulic pressure of the hydraulic line 10 that measures the hydraulic pressure of the hydraulic line 10. It includes a pressure measuring means 30, a flow rate measuring means 40 for measuring the flow rate of the hydraulic line 10, and a controller 50 for controlling the valve opening/closing operation of the pressure control valve 20.

The hydraulic line 10 includes a hydraulic power source 12, a tank 14, a pipe 16 connecting these, and a pressure gauge 18 connected to the pipe 16.

The pressure control valve 20 used in this embodiment is as follows:
It is constructed by combining a pilot relief valve 21 and a balance piston type main valve 22. The pilot relief valve 21 can be a known one, and includes, for example, a hydraulic mechanism part and a DC solenoid part.

The pressure measuring means 30 is a hydraulic sensor that measures the pressure in the hydraulic line 10 and outputs it as an electrical signal. The output signal of this pressure measuring means is sent to the controller 50.

The flow rate measuring means 40 is a flow rate sensor that measures the flow rate of the hydraulic line 10 and outputs it as an electrical signal. The output signal of this flow rate measuring means 40 is inputted to the controller 50 as a flow rate command Q. Note that the flow rate measuring means 40 is not limited to a flow rate sensor. For example, the flow rate can be determined from the input value using a proportional electromagnetic flow control valve that can detect and calculate the flow rate. In addition, if the hydraulic power source is a combination of fixed multi-stage pumps,
The flow rate value can be determined from the pump that is on-load. Furthermore, the hydraulic line using the fixed pump 1 as the hydraulic source is connected to the pressure control valve 2 used in this embodiment.
0 and a flow rate adjustment valve for other drives, the flow rate of the pressure control valve 20 is determined from "pump flow rate (known) - flow rate adjustment valve flow rate (input current value)".

The controller 50 is constituted by a computer system, for example, as shown in FIG. This system includes an A/D converter 51 that performs analog/digital conversion on each of the pressure signal from the pressure sensor 31, the flow rate command Q from the flow rate measurement means 40, and the target value r, and a control operation to be performed by the controller 50. A central processing unit (CPU) 52 to execute and a read-only memory (ROM) to store programs executed by the CPU 52.
) 53 and a rewritable non-volatile memory (EEPRO
M) 54, a random access memory (55) serving as a work area for calculations, an operation input unit 58 for externally giving instructions to the CPU 52, setting parameters, etc., and operations obtained by control calculations of the CPU 52. It is configured to include a D/A converter 56 that converts a signal into an analog voltage, and a V/I converter 57 that converts the converted analog voltage into a current.

The ROM 53 contains a program executed by the CPU 52 which describes a procedure for measuring the static characteristics of an actual pressure control valve, which indicates the relationship between the control amount and the operation signal, and a program that describes the obtained static characteristics. A program describing a procedure for generating an operation signal for obtaining a control amount corresponding to a target value based on the target value, and a program for controlling the controller 50 itself are stored.

Regarding the operation of this embodiment, we will explain the procedure for measuring the static characteristics of an actual pressure control valve, which shows the relationship between the control amount and the operation signal, and the control amount corresponding to the target value based on the obtained static characteristics. This will be explained along with the procedure for generating the operation signal to obtain the following. First, in the normal usage range of the pressure control valve used, the flow rate is divided into large flow rate, medium flow rate, and small flow rate as necessary. In this embodiment, there are three categories: large, medium, and small. The flow rate signal at a large flow rate is Q0, the flow rate signal at a medium flow rate is Q1, and the flow rate signal at a small flow rate is Q2.

The procedure for measuring the static characteristics indicating the relationship between the control amount and the operation signal for an actual pressure control valve will be explained with reference to FIGS. 3, 4, and 5. Here, the measurements are performed in order of decreasing flow rate.

The flow rate can be set from the operation input section 58. Further, this measurement process can also be started from the operation input section 58. The CPU 52 is activated by an instruction from the operation input unit 58, reads out from the ROM 53 a program that describes a procedure for measuring the static characteristics indicating the relationship between the control amount and the operation signal for the actual pressure control valve, and sequentially executes the program. do.

First, the CPU 52 receives the flow rate setting from the operation input section 58 and executes the operation amount-pressure measurement process (steps 301, 302). When this is finished,
Similarly, the CPU 52 executes measurement processing in the order of medium flow rate and large flow rate (steps 303 to 306).

In the operation amount-pressure measurement process 302, as shown in FIG. 4, first, the operation amount X is set to 0 (step 311). Next, this manipulated variable X is sequentially increased and output (step 312). In this case, the manipulated variable X is a ramp voltage that changes slowly or a step voltage that changes in a minute width. This manipulated variable X is converted into an analog voltage by the D/A converter 56, further converted into a current by the V/I converter 57, and input to the pressure control valve 20. As a result, the opening degree of the pressure control valve 20 changes, and the pressure in the hydraulic line 10 changes.

This pressure change in the pressure line 10 is detected by a pressure sensor 31. The detected pressure signal is captured at predetermined sampling intervals and converted into a digital signal by the A/D converter 51. and,
The data is captured by the CPU 52 and stored in the EEPROM 54 (step 313).

Next, the CPU 52 executes the calculation "X=X+ΔX" for the current manipulated variable X, and determines the next manipulated variable to be measured (step 314). Here, since the storage capacity of the EEPROM 54 is limited for the operation amount to be sampled, the number of measurement points for one curve is determined in advance from the storage capacity of the EEPROM 54 and the static characteristic curve. For example, if the maximum input X is Xmax, as shown in FIG.
Measure the pressure Y every -1). ΔX is determined corresponding to the interval between the measurement points. And this X is Xmax
The steps 312 to 314 are repeated until X exceeds Xmax, and when X exceeds Xmax, the measurement for the set flow rate ends (Step 315).

In this way, for each of large, medium, and small flow rates, the static characteristics showing the relationship between the control amount and the operation signal are
Each is stored in the EEPROM 54 and made into a table. FIG. 6 shows an example of the format of this type of table. Of course, the table format is not limited to this.

Note that during this measurement, the hydraulic line 1
0 is assumed to be maintained within the set flow rate range. Furthermore, the above measurements need only be performed once when the fluid control system is installed. However, it goes without saying that it can be executed as appropriate depending on changes in the environment.

Next, the case where the target value r is input to the controller 50 to obtain the desired pressure in the hydraulic line 10 will be described with reference to FIGS. 7, 8, 9, and 10.

First, a procedure will be described in which the CPU 52 is activated upon receiving an instruction from the operation input section 58, and generates an operation signal for obtaining a control amount corresponding to a target value based on the obtained static characteristics. The program is read from the ROM 53 and executed. By executing this program, the CPU 52, together with the EEPROM 54, creates a flow rate determination means 501 that determines whether the flow rate Q is a large flow rate, a medium flow rate, or a small flow rate based on the flow rate signal Q, as shown in FIG. , functions as an operation signal generation means 502 that generates an operation signal according to the determined flow rate classification. This operation signal generation means 502 includes a static characteristic storage means 504 that stores the static characteristics obtained by the above measurement, and a static characteristic storage means 504 that stores the static characteristics obtained by the above measurement.
Using a finite number of previously observed points stored in
By performing linear interpolation between two points, the closest pressure command y is found from the target value r, and this y is used to determine the manipulated variable x.
, and generates and outputs the operation signal X from the linear interpolation means 503.

According to the flowchart of FIG. 8, the CPU 52 first takes in the target pressure value r, and converts this into the A/D.
It is converted into a digital signal by the converter 51 (step 801). Also, take in the flow rate command value (signal) Q,
This is converted into a digital signal by the A/D converter 51 (step 802). It is determined whether the captured flow rate Q is between large, medium, and small (step 803).
). Now, assuming that this flow rate Q is between a large flow rate and a medium flow rate, the manipulated variables x1 and x2 for the target value r are determined for each of the two flow rates (step 804). Then, for those two manipulated variables x1 and x2, 1
Next interpolation is performed to find the final manipulated variable x0 (step 80
5). The obtained manipulated variable x0 is outputted as an analog voltage by the D/A converter 56 (step 806).

By repeating this at regular intervals, even if there is a change in the target value or a fluctuation in the flow rate, the output of the pressure control valve 20 used in the open loop can be made to substantially match the target value.

The linear interpolation algorithm will now be explained with reference to FIG. First, to calculate the manipulated variable x0 for the target value r, take the target value r on the vertical axis y, consider a straight line that passes through the target value r and is parallel to the x-axis, and consider that this straight line is a curve showing the static characteristics of the pressure at a large flow rate Q0. x coordinate of the intersecting point (x1)
seek. In order to obtain this x1, the CPU 52 checks between which measurement points the target value r falls from the table of static characteristics shown in FIG. Now, that point is (x2, y
2), (x3, y3). x1 is obtained by linear interpolation between these two points using the following equation. x1=x2+(r-y2)(x3-x2)
/(y3-y2) Similarly, the x-coordinate (x4) of the point where a straight line passing through the target value r and parallel to the x-axis intersects with the curve showing the static characteristics of the pressure of the medium flow rate Q1 is determined by the following equation. x4=x5+(r-y5)(x6-x5)
/(y6-y5) Furthermore, since the flow rate is between a large flow rate and a medium flow rate, linear interpolation is performed between x1 and x2 with respect to the flow rate Q using the following formula, and the final output (operated amount) x0 seek. x=x1+(x4-x1)(Q-Q0)/(Q1-Q0
) Thereby, even if there is a change in the flow rate, it is possible to accurately linearize the correspondence between the control amount and the target value. Therefore, as shown in FIG. 10, it can be seen that the pressure in the hydraulic line 10 linearly corresponds to the input (target value) to the controller 50, regardless of the magnitude of the flow rate. Also,
In this embodiment, since the static characteristics of the corresponding pressure control valve 20 can be measured by the controller 50 itself, linearization can be performed, including machine differences in the pressure control valve 20, and more accurate control is possible. Become.

Next, regarding another embodiment of the present invention, FIG.
This will be explained with reference to 1. The embodiment shown in FIG. 11 includes a hydraulic line 10, a pressure control valve 20 provided therein, a flow rate measuring means 40, and a controller 60.

[0044] In this embodiment, the controller 60 itself does not have a means for measuring the static characteristic relationship indicating the relationship between the manipulated variable and the pressure, but stores data indicating this relationship measured in advance. This embodiment differs from the embodiment shown in FIG. 1 above in that the embodiment shown in FIG. Note that, in other respects, the configuration is similar to that of the embodiment shown in FIG. 1 above. Therefore, only the differences will be explained here.

[0045] The controller 60 is constituted by a hardware system similar to that of the controller 50 shown in FIG. That is, the A/D converter 51, the CPU 52, the ROM 53, the EEPROM 54, and the RAM 55.
It includes a D/A converter 56 and a V/I converter 57. Here, the first difference from the controller 50 is that the system of this embodiment does not require a pressure sensor, and therefore
This is because the signal from the pressure sensor 31 is not input to the D converter 51. The second difference is that the ROM 5
Third, there is no program installed for this processing. Furthermore, the third difference is that the static characteristics indicating the relationship between the control amount and the operation signal stored in the EEPROM 54 are calculated from pre-measured data and design values before the controller 60 is incorporated into the fluid control system. The point is that it uses data etc.

The fluid control system of this embodiment transmits the flow rate signal Q from the flow rate measuring means 40 and the target value r to the controller 6.
0, the pressure in the hydraulic line 10 in the system can be controlled. As described above, since the system of this embodiment does not take into account the machine difference of the pressure control valve 20, the accuracy in this respect is inferior to the embodiment shown in FIG. 1 above. However, since measurement processing for determining static characteristics is not performed, the burden on the controller can be reduced, and manufacturing can be made at a correspondingly low cost. Therefore, in the case of control that does not require much precision, it can be suitably used when there is little machine difference between the pressure control valves.

Although each of the embodiments described above is an example in which a pilot relief valve and a balance piston type main valve are combined, the present invention is not limited to this. It is also applicable to other types of valves. Furthermore, the present invention is not limited to pressure control valves, but can be applied to fluid control systems that incorporate nonlinear valves that are used in open loops. Furthermore, although each of the above embodiments has been applied to a hydraulic system, the present invention is not limited thereto.

[0048]

According to the present invention, it is possible to improve the nonlinearity of a proportional control valve and realize a fluid control system that can obtain a controlled amount according to a set value even when used in an open loop. Further, according to the present invention, it is possible to realize a controller that improves the nonlinearity of a proportional control valve and controls the proportional control valve so that a controlled amount according to a set value can be obtained even when used in an open loop.

Furthermore, according to the present invention, even when used in an open loop, the control amount can be obtained in accordance with the set value.
Nonlinearity of the proportional control valve can be improved.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing the configuration of an embodiment of a fluid control system of the present invention.

FIG. 2 is a block diagram showing a hardware system configuration of an embodiment of a controller used in the fluid control system of the present invention.

FIG. 3 is a flowchart illustrating an overview of the procedure of a manipulated variable-pressure measurement process in an embodiment of the present invention.

FIG. 4 is a flowchart showing details of the procedure of operation amount-pressure measurement processing in the flowchart shown in FIG. 3;

FIG. 5 is a graph showing the relationship between input points and pressure during operation amount-pressure measurement processing in an embodiment of the present invention.

FIG. 6 is a table showing the relationship between operating point and pressure for each flow rate.

FIG. 7 is a block diagram showing a function of performing linearization processing to obtain a control amount linearly with respect to a target value in an embodiment of the present invention.

FIG. 8 is a flowchart showing a procedure of linearization processing for linearly obtaining a control amount for a target value in an embodiment of the present invention.

FIG. 9 is a graph for explaining interpolation in linearization processing.

FIG. 10 is a graph showing the relationship between input to a controller and its output, which is an embodiment of the present invention.

FIG. 11 is a system diagram showing the configuration of another embodiment of the fluid control system of the present invention.

FIG. 12 is a graph showing input/output characteristics of a proportional pressure control valve.

[Explanation of symbols]

10... Hydraulic line, 12... Hydraulic source, 14... Tank, 16
... Piping, 20... Pressure control valve, 21... Pilot relief valve, 22... Main valve, 30... Pressure measuring means, 40... Flow rate measuring means, 50, 60... Controller.

Claims (10)

[Claims] 1. A fluid line to be controlled, a proportional control valve that controls the fluid to a desired state according to an operation signal corresponding to a target value, and a proportional control valve that measures a parameter indicating the state of the fluid in the fluid line. 1, a storage means for storing the results of pre-measurement of the correspondence between the operation signal and the fluid control state at a plurality of points in the operating range of the proportional control valve with respect to the pre-designated parameters; and a target value. is applied to the control state of the fluid stored in the storage means according to the value of the parameter representing the state of the fluid line measured by the first measurement means, and an operation signal corresponding to the control state is obtained. 1. A fluid control system comprising: a signal generating means, the operating signal driving a proportional control valve to control a fluid line. 2. A second measuring means for measuring a control state of the fluid line to be controlled;
Generate operating signals at multiple points in the operating range of the proportional control valve under specified parameters to drive the proportional control valve, take in the corresponding measurement results of the second measuring means, and generate the operating signals. A fluid control system further comprising: third measuring means for measuring the correspondence between the control state and the control state. 3. A controller that controls a proportional control valve installed in a fluid line by outputting an operation signal corresponding to a target value, the controller controlling a proportional control valve provided in a fluid line by outputting an operation signal corresponding to a target value, the controller controlling a proportional control valve provided in a fluid line by outputting an operation signal corresponding to a target value, a storage means for storing a result of pre-measurement of a parameter indicating a state of the fluid in the fluid line specified in advance as a correspondence relationship with the control state;
an operation signal generation means for applying the target value to the fluid control state stored in the storage means according to the value of a parameter representing the state of the fluid line given from the outside to obtain a corresponding operation signal; A controller for fluid control, comprising: a controller for controlling a fluid; and controlling a proportional control valve using the operation signal. 4. According to claim 3, generating operation signals at a plurality of points in the operating range of the proportional control valve under specified parameters to drive the proportional control valve;
A controller for fluid control, further comprising a measuring means for externally importing a measurement result of a corresponding fluid control state and measuring the correspondence between the operation signal and the control state. 5. The fluid control system according to claim 1, wherein the first measuring means measures a flow rate as a parameter indicating the state of the fluid in the fluid line. 6. In claim 2, the first measuring means measures the flow rate as a parameter indicating the state of the fluid in the fluid line, and the second measuring means measures the flow rate of the fluid to be controlled. A fluid control system that measures fluid pressure as a line control condition. 7. The fluid control controller according to claim 3, wherein the proportional control valve to be controlled is a pressure control valve. 8. The fluid control system according to claim 1, wherein the fluid line to be controlled is a hydraulic line. 9. The fluid control controller according to claim 3, wherein the proportional control valve to be controlled is for hydraulic pressure. 10. Regarding a proportional control valve that controls a fluid to a target state in response to an operation signal corresponding to a target value, a correspondence relationship between the operation signal and the control state of the fluid at a plurality of points in the operating range of the proportional control valve. Based on the results of pre-measurement of
A proportional control valve linearization method that applies a target value to the fluid control state, obtains a corresponding operation signal, and controls the proportional control valve using this operation signal.