Flow control device and flow correcting method therefor

Abstract

A flow rate control device and a flow rate correction method are disclosed, which allow the set fluid discharge amount and the actual discharged flow rate to match each other regardless of the external environment. A flow rate correction method is a method for correcting a flow rate discharged using a flow rate control device, comprising: a step of deriving a first table representing the relative ratio of the temperature of a constant environment, the internal temperature of the flow rate control device, the temperature of the incoming fluid, and the flow rate of the incoming fluid in an environment where the fluid discharge setting amount and the actual fluid discharge amount are constant; a step of deriving a second table representing the relative ratio of the difference between the fluid discharge setting amount and the actual fluid discharge amount and the difference between the internal temperature and the incoming fluid temperature in an environment where the fluid discharge setting amount and the actual fluid discharge amount are different; and a step of correcting the actual fluid discharge amount using the first table and the second table so that the actual fluid discharge amount becomes equal to the fluid discharge setting amount in an environment where the fluid discharge setting amount and the actual fluid discharge amount are different.

Description

Technology Field

[0001] The present invention relates to a flow rate control device and a flow rate correction method, and more specifically, to a flow rate control device and a flow rate correction method capable of correcting a discharged flow rate. Background Technology

[0002] A mass flow controller (MFC) is a device that precisely controls the flow rate of gas. Recently, as mass flow controllers are being applied to semiconductor manufacturing equipment that mass-produces high-density components, there is increasing demand and interest in mass flow controllers that can precisely control fluid flow at high speeds.

[0003] A typical mass flow meter includes a temperature sensor for measuring the temperature of the incoming fluid, a control valve for regulating the flow rate by opening and closing the flow path, a cooling element, a flow sensor for detecting the discharged flow rate, and a controller.

[0004] These mass flow meters set the discharge flow rate at the controller and transmit a control signal value corresponding to the set discharge amount to the control valve to regulate the flow rate of the incoming fluid.

[0005] Conventional mass flow meters have a problem in which the set discharge flow rate differs from the actual discharge flow rate depending on the installation environment, which leads to a decrease in the precision of flow control. Prior art literature

[0006] (Patent Document 0001) JP 2117842 B2 The problem to be solved

[0007] The present invention aims to solve the above-mentioned problems by providing a flow control device and a flow correction method capable of discharging fluid at a set value regardless of the environment in which the flow control device is installed. means of solving the problem

[0008] A flow rate correction method according to embodiments of the present invention for solving the above problem is a method for correcting a flow rate discharged using a flow rate control device, comprising: a step of deriving a first table in which, in an environment where a fluid discharge setting amount and an actual fluid discharge amount are constant, the temperature of the constant environment, the internal temperature of the flow rate control device, the temperature of the incoming fluid of the flow rate control device, and the relative ratio of the flow rate of the incoming fluid; a step of deriving a second table in which, in an environment where a fluid discharge setting amount and an actual fluid discharge amount are different, the temperature of the different environment, the difference value between the fluid discharge setting amount and the actual fluid discharge amount, and the difference value between the internal temperature and the temperature of the incoming fluid; and a step of correcting the actual fluid discharge amount using the first table and the second table in an environment where a fluid discharge setting amount and an actual fluid discharge amount are different, so that the actual fluid discharge amount becomes equal to the fluid discharge setting amount.

[0009] The step of correcting the actual discharge amount of the above fluid is a flow rate correction method that calculates a control signal value for controlling the inflow amount of the above fluid through the following relationship.

[0010] [Relationship]

[0011] y = y' + (k * a * r * x)

[0012] (Here, y is a control signal value corrected so that the fluid discharge setting amount and the actual fluid discharge amount are equal, y' is a control signal value before the fluid discharge setting amount is corrected, k is a value obtained by multiplying the ratio of the internal temperature of the flow control device in a constant environment to the internal temperature of the flow control device in a different environment by a proportionality constant, a is a value obtained by dividing the control signal value corresponding to the fluctuation amount by 1°C, r is a percentage value relative to the fluid discharge setting amount, and x is the difference between the expected temperature of the incoming fluid corresponding to the fluid discharge setting amount and the measured actual temperature of the incoming fluid when the internal temperature of the flow control device in a different environment is matched to the internal temperature of the first table.)

[0013] The step of deriving the first table comprises: placing the flow control device within an ideal circumstance; changing the temperature of the ideal circumstance to different temperatures and measuring the internal temperature, the temperature of the incoming fluid, and the flow rate of the fluid at each of the different temperatures to calculate a relative ratio; and deriving relative ratios for all temperatures between the minimum and maximum temperatures among the different temperatures using a plurality of relative ratios measured at each of the different temperatures.

[0014] The step of calculating the relative ratio comprises: a step of calculating a first ratio representing a relative ratio regarding the difference between the internal temperature and the temperature of the incoming fluid, by setting the abnormal environment to a first abnormal environment temperature; and a step of calculating a second ratio representing a relative ratio regarding the difference between the internal temperature and the temperature of the incoming fluid, by setting the abnormal environment to a second abnormal environment temperature; and the step of deriving the relative ratios comprises: a step of interpolating the first ratio and the second ratio to calculate the first table, which is a table of relative ratios regarding the difference between the internal temperature and the temperature of the incoming fluid, the maximum flow rate to the minimum flow rate of the flow control device, and the temperature of the incoming fluid.

[0015] The step of calculating the first ratio comprises: measuring the first internal temperature of the flow control device at the first abnormal environment temperature; setting the flow control device to discharge a first flow rate fluid and measuring the first inlet temperature of the inlet fluid flowing into the flow control device; calculating the difference between the first internal temperature and the first inlet temperature and the first-1 ratio representing the relative ratio of the first flow rate; setting the flow control device to discharge a second flow rate fluid and measuring the second inlet temperature of the inlet fluid flowing into the flow control device; calculating the difference between the first internal temperature and the second inlet temperature and the first-2 ratio representing the relative ratio of the second flow rate; setting the flow control device to discharge a third flow rate fluid and measuring the third inlet temperature of the inlet fluid flowing into the flow control device; and calculating the difference between the first internal temperature and the third inlet temperature and the first-3 ratio representing the relative ratio of the third flow rate. The method includes the step of calculating the first ratio, which represents the relative ratio of the difference between the internal temperature and the temperature of the incoming fluid, using the first-1 ratio, the first-2 ratio, and the first-3 ratio, which are in constant proportion to each other.

[0016] The step of calculating the second ratio comprises: measuring the second internal temperature of the flow control device at the second abnormal environment temperature; setting the flow control device to discharge a first flow rate fluid and measuring the fourth inlet temperature of the inlet fluid flowing into the flow control device; calculating the difference between the second internal temperature and the fourth inlet temperature and the second-1 ratio representing the relative ratio of the first flow rate; setting the flow control device to discharge a second flow rate fluid and measuring the fifth inlet temperature of the inlet fluid flowing into the flow control device; calculating the difference between the second internal temperature and the fifth inlet temperature and the second-2 ratio representing the relative ratio of the second flow rate; setting the flow control device to discharge a third flow rate fluid and measuring the sixth inlet temperature of the inlet fluid flowing into the flow control device; and calculating the difference between the second internal temperature and the sixth inlet temperature and the second-3 ratio representing the relative ratio of the third flow rate. The method includes the step of calculating the second ratio, which represents the relative ratio of the difference between the internal temperature and the temperature of the incoming fluid, using the second-1 ratio, the second-2 ratio, and the second-3 ratio, which are in constant proportion to each other.

[0017] The step of deriving the second table comprises: a step of placing the flow control device within a real circumstance; a step of changing the temperature of the real circumstance to different temperatures and, at each temperature, measuring the fluctuation amount, which is the difference between the fluid discharge setting amount and the actual fluid discharge amount, and the difference between the internal temperature and the temperature of the incoming fluid, and calculating a relative ratio; and a step of deriving relative ratios for all temperatures between the minimum temperature and the maximum temperature among the different temperatures using a plurality of relative ratios measured at each of the different temperatures.

[0018] The step of calculating the relative ratio comprises: a step of setting the real environment to a first real environment temperature and calculating a third ratio representing the relative ratio of the difference between the expected temperature of the inflow fluid confirmed through the first table and the actual temperature of the inflow fluid measured, with respect to the fluctuation amounts of each of the maximum to minimum flow rates of the flow control device; and a step of setting the ideal environment to a second real environment temperature and calculating a fourth ratio representing the relative ratio of the difference between the expected temperature of the inflow fluid confirmed through the first table and the actual temperature of the inflow fluid measured, with respect to the fluctuation amounts of each of the maximum to minimum flow rates of the flow control device; and the step of deriving the relative ratios comprises: a step of interpolating the third ratio and the fourth ratio to each other to calculate the second table, which is a table of relative ratios for the difference between the expected temperature of the inflow fluid and the actual temperature of the inflow fluid measured, with respect to the fluctuation amounts of each of the maximum to minimum flow rates of the flow control device and the first real environment temperature to the second real environment temperature.

[0019] The step of calculating the third ratio comprises: measuring the third internal temperature in the first real environment; setting the flow control device to discharge a fluid of the first flow rate and, based on the state where the third internal temperature is matched to the corresponding internal temperature in the first table, checking the first expected temperature of the incoming fluid corresponding to the first flow rate; measuring the first actual temperature of the incoming fluid and calculating the first difference value between the measured first actual temperature and the first expected temperature; measuring the actual fluid discharge amount and calculating the first fluctuation amount, which is the difference between the measured actual fluid discharge amount and the first flow rate; calculating the third-1 ratio representing the relative ratio between the first difference value and the first fluctuation amount; setting the flow control device to discharge a fluid of the second flow rate and, based on the state where the third internal temperature is matched to the corresponding internal temperature in the first table, checking the second expected temperature of the incoming fluid corresponding to the second flow rate; The method comprises: a step of measuring a second actual temperature of the incoming fluid and calculating a second difference value between the measured second actual temperature and the second expected temperature; a step of remeasuring the actual discharge amount of the fluid and calculating a second fluctuation amount which is the difference between the remeasured actual discharge amount of the fluid and the second flow rate; a step of calculating a third-2 ratio representing the relative ratio between the second difference value and the second fluctuation amount; and a step of calculating the third ratio representing the relative ratio between the difference value between the expected temperature and the measured actual temperature and the fluctuation amounts of the maximum to minimum flow rates of the flow rate control device, using the third-1 ratio and the third-2 ratio which are proportionally equal to each other.

[0020] The step of calculating the fourth ratio comprises: measuring the fourth internal temperature in the second real environment; setting the flow control device to discharge a fluid of the first flow rate and, based on the state where the fourth internal temperature is matched to the corresponding internal temperature in the first table, checking the third expected temperature of the incoming fluid corresponding to the first flow rate; measuring the third actual temperature of the incoming fluid and calculating the third difference value between the measured third actual temperature and the third expected temperature; measuring the actual fluid discharge amount and calculating the third fluctuation amount, which is the difference between the measured actual fluid discharge amount and the first flow rate; calculating the 4-1 ratio representing the relative ratio between the third difference value and the third fluctuation amount; setting the flow control device to discharge a fluid of the second flow rate and, based on the state where the third internal temperature is matched to the corresponding internal temperature in the first table, checking the fourth expected temperature of the incoming fluid corresponding to the second flow rate; The method comprises: a step of measuring a fourth actual temperature of the incoming fluid and calculating a fourth difference value between the measured fourth actual temperature and the second expected temperature; a step of remeasuring the actual discharge amount of the fluid and calculating a fourth fluctuation amount which is the difference between the remeasured actual discharge amount of the fluid and the second flow rate; a step of calculating a 4-2 ratio representing the relative ratio between the fourth difference value and the fourth fluctuation amount; and a step of calculating the 4 ratio representing the relative ratio between the difference value between the expected temperature and the measured actual temperature and the fluctuation amounts of the maximum to minimum flow rates of the flow rate control device, using the 4-1 ratio and the 4-2 ratio which are constantly proportional to each other.

[0021] The step of correcting the actual fluid discharge amount above involves deriving 'a', a control signal value corresponding to the fluid fluctuation amount in the above relationship, by using a third table, which is a table of the control signal value of the flow rate control device and the preset fluctuation amount of the flow rate control device in the above constant environment, to verify the control signal value corresponding to the fluctuation amount.

[0022] A flow control device according to one embodiment of the present invention comprises: a housing; a fluid pipe installed inside the housing and having an inlet pipe for introducing fluid and a discharge pipe for discharging fluid; a cooling element coupled to the fluid pipe and for cooling the fluid passing through the fluid pipe; a sensor module for measuring an external temperature of the housing, an internal temperature of the housing, a temperature of an inlet fluid entering the housing, and a flow rate of a discharged fluid; and a controller connected to the sensor module and correcting the discharge amount of fluid using a first table indicating the relative ratio of the internal temperature, the temperature of the inlet fluid, and the flow rate of the inlet fluid, and a second table indicating the relative ratio of the difference between the set discharge amount of the fluid and the actual discharge amount of the fluid and the difference between the internal temperature and the temperature of the inlet fluid.

[0023] The above housing is provided inside a facility that uses a fluid, and the sensor module includes a first sensor installed in the housing and measuring the temperature of the facility, a second sensor installed in the housing and measuring the internal temperature of the housing, a third sensor installed in the inlet pipe and measuring the temperature of the inlet fluid, and a fourth sensor installed in the discharge pipe and measuring the flow rate of the discharged fluid, and the controller receives signals from the first to the fourth sensors and uses the received signals to adjust the degree of opening of the inlet pipe.

[0024] The above fluid piping includes a valve that controls the internal diameter into which the fluid flows; and the controller generates a corrected control signal value through the following relationship and controls the valve with the corrected control signal value so that the actual discharge amount of fluid in the discharge piping becomes equal to the set discharge amount of the fluid.

[0025] [Relationship]

[0026] y = y' + (k * a * r * x)

[0027] (Here, y is a control signal value corrected so that the fluid discharge setting amount and the actual fluid discharge amount are equal, y' is a control signal value before the fluid discharge setting amount is corrected, k is a value obtained by multiplying a proportionality constant by the ratio of the internal temperature of the housing in an ideal environment not placed inside the facility to the internal temperature of the housing in a real environment placed inside the facility, a is a value obtained by dividing the control signal value corresponding to the fluctuation amount, which is the difference between the fluid discharge setting amount and the actual fluid discharge amount, by 1°C, r is a percentage value relative to the fluid discharge setting amount, and x is the difference between the expected temperature of the incoming fluid corresponding to the fluid discharge setting amount and the measured actual temperature of the incoming fluid when the internal temperature of the flow control device placed inside the facility is matched to the internal temperature of the first table.) Effects of the invention

[0028] According to the present invention, the discharge amount of the fluid being discharged can be corrected by using the internal temperature of the flow control device and the temperature of the fluid flowing into the flow control device.

[0029] In addition, through fluid discharge volume correction, fluid can be discharged at a set value regardless of the operating environment of the fluid control device, and the precision of flow rate control is improved. Brief explanation of the drawing

[0030] FIG. 1 is a drawing illustrating the structure of a flow rate control device according to one embodiment of the present invention. FIG. 2 is a flowchart of a flow rate correction method according to one embodiment of the present invention. Figure 3 is a graph showing the relationship between the internal temperature and the temperature of the incoming fluid when the flow control device is adjusted to the first abnormal environment temperature in an abnormal environment. Figure 4 is a graph showing the relationship between the internal temperature and the temperature of the incoming fluid when the flow control device is adjusted to the second abnormal environment temperature in an abnormal environment. Figure 5 is a graph regarding the first table. Figure 6 is a graph showing the relationship between the temperature of the incoming fluid and the fluid flow rate in a real environment where the flow control device is controlled to the first ideal environment temperature. Figure 7 is a graph showing the relationship between the temperature of the incoming fluid and the fluid flow rate in a real environment where the flow control device is controlled to the second ideal environment temperature. Figure 8 is a graph regarding the second table. Figure 9 is a graph regarding the third table. Specific details for implementing the invention

[0031] The embodiments described in this specification may be modified in various ways. Specific embodiments may be depicted in the drawings and described in detail in the detailed description. However, specific embodiments disclosed in the accompanying drawings are intended only to facilitate understanding of various embodiments. Accordingly, the technical concept is not limited by specific embodiments disclosed in the accompanying drawings, and it should be understood that it includes all equivalents or substitutions that fall within the spirit and scope of the invention.

[0032] Terms including ordinal numbers, such as first, second, etc., may be used to describe various components, but these components are not limited by the aforementioned terms. The aforementioned terms are used solely for the purpose of distinguishing one component from another.

[0033] In this specification, terms such as “comprising” or “having” are intended to specify the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof. When a component is described as being “connected” or “connected” to another component, it should be understood that it may be directly connected to or connected to that other component, or that there may be other components in between. On the other hand, when a component is described as being “directly connected” or “directly connected” to another component, it should be understood that there are no other components in between.

[0034] Meanwhile, a "module" or "part" for a component as used in this specification performs at least one function or operation. Furthermore, a "module" or "part" may perform a function or operation by hardware, software, or a combination of hardware and software. Additionally, a plurality of "modules" or a plurality of "parts," excluding a "module" or "part" that must be performed on specific hardware or on at least one processor, may be integrated into at least one module. A singular expression includes a plural expression unless the context clearly indicates otherwise.

[0035] Furthermore, in describing the present invention, if it is determined that a detailed description of related known functions or configurations may unnecessarily obscure the essence of the invention, such detailed description is abbreviated or omitted.

[0036] Various embodiments are described in more detail below with reference to the attached drawings.

[0038] FIG. 1 is a drawing illustrating the structure of a flow rate control device according to one embodiment of the present invention.

[0039] Hereinafter, with reference to FIG. 1, the structure of a flow rate control device (100) according to one embodiment of the present invention will be described. It is a device for controlling a large flow rate of fluid supplied to a facility (10) to a preset low flow rate, which is applied to a facility that uses fluid (e.g., semiconductor manufacturing equipment).

[0040] A flow control device (100) according to one embodiment of the present invention includes a housing (110), a fluid pipe (120), a sensor module (130), a cooling element (140), and a controller (150).

[0041] The housing (110) is installed inside the facility (10) and has an internal space (S).

[0042] In addition, a first sensor (131) is installed on the outer surface of the housing (110).

[0043] Additionally, in the internal space (S) of the housing (110), a part of the inlet pipe (121) (connecting pipe (122)), a cooling element (140), a part of the sensor module (130) (second sensor (132)), and a controller (150) are installed.

[0044] The fluid pipe (120) is connected to the housing (110) and is a passage through which fluid travels.

[0045] The fluid piping (120) includes an inlet pipe (121), a connecting pipe (122), a discharge pipe (123), and a valve (124).

[0046] The inlet pipe (121) is installed at the front of the outer surface of the housing (110). The inlet pipe (121) is connected to the inlet pipe (11) of the equipment (10) and is a passage through which a large volume of fluid flowing in through the inlet pipe (11) is introduced into the flow control device (100). The inner diameter of the inlet pipe (121) is formed to be smaller than the inner diameter of the inlet pipe (11).

[0047] Additionally, a valve (124) is installed in the inlet pipe (121). The internal diameter of the inlet pipe (121) is controlled through the valve (124).

[0048] In addition, a third sensor (133) is installed in the inlet pipe (121).

[0049] The connecting pipe (122) is installed inside the housing (110) and connects the inlet pipe (121) and the discharge pipe (123) to each other.

[0050] A cooling element (140) is installed in the connecting pipe (122), and a large flow rate of fluid is controlled to a preset low flow rate through the cooling element (140).

[0051] The discharge pipe (123) is installed at the rear end of the outer surface of the housing (110). The discharge pipe (123) is connected to the discharge pipe (12) of the equipment (10) and is a passage through which fluid is discharged, the flow rate of which is controlled to a low flow rate by the cooling element (140) in the connecting pipe (122). The inner diameter of the discharge pipe (123) can be formed to be the same as the inner diameter of the discharge pipe (12).

[0052] In addition, a fourth sensor (134) is installed in the discharge pipe (123).

[0053] The valve (124) controls the inner diameter of the inlet pipe (121) into which fluid flows. The valve (124) is operated by receiving a control signal value from the controller (150). The valve (124) may be provided as a piezo valve.

[0054] The sensor module (130) measures the external temperature of the housing (110) (i.e., the internal temperature of the facility (10)), the internal temperature of the housing (110), the temperature of the inflow fluid flowing into the housing (110), and the flow rate of the discharged fluid.

[0055] The sensor module (130) includes a first sensor (131), a second sensor (132), a third sensor (133), and a fourth sensor (134).

[0056] The first sensor (131) is installed on the outer surface of the housing (110) and measures the internal temperature (i.e., internal atmosphere temperature) of the equipment (10).

[0057] A second sensor (132) is installed on the inner surface of the housing (110) and measures the internal temperature (i.e., internal atmosphere temperature) of the housing (110). Through the second sensor (132), the internal temperature (i.e., first internal temperature to fourth internal temperature) is measured.

[0058] A third sensor (133) is installed in the inlet pipe (121) and measures the temperature of the fluid flowing into the inlet pipe (121). Through the third sensor (133), the temperature of the inlet fluid (i.e., the first inlet temperature to the sixth inlet temperature) is measured.

[0059] The fourth sensor (134) is installed in the discharge pipe (123) and measures the flow rate of the discharged fluid. Through the fourth sensor (134), the actual discharge amounts of the fluid are measured.

[0060] A cooling element (140) is connected to a connecting pipe (122) and cools the fluid passing through the connecting pipe (122) so that a large flow rate of fluid in the connecting pipe (122) is controlled to a low flow rate. The cooling element (140) may be provided as a Peltier element.

[0061] The controller (150) is installed inside the housing (110) and connected to the sensor module (130), and controls the degree of opening of the inlet pipe (121) using signals transmitted from the first sensor (131) to the fourth sensor (134) of the sensor module (130). The controller (150) controls the operation of the valve (124) installed in the inlet pipe (121) to control the internal diameter of the inlet pipe (121).

[0062] The controller (150) corrects the fluid discharge amount using a first table showing the relative ratio of the internal temperature of the housing (110), the temperature of the incoming fluid, and the flow rate of the incoming fluid, and a second table showing the relative ratio of the difference between the fluid discharge setting amount and the actual fluid discharge amount and the difference between the internal temperature of the housing (110) and the temperature of the incoming fluid.

[0063] The controller (150) creates a first table and a second table and stores the tables. Additionally, the controller (150) stores a third table in advance, which is a table showing the correlation between the control signal value and the fluctuation amount (and fluid flow rate) used by the flow control device (100) to calculate the initial control signal value.

[0064] The controller (150) generates a correction control signal value through the following relationship and controls the valve (124) with the correction control signal value so that the actual discharge amount of fluid from the discharge pipe (123) becomes equal to the set discharge amount of fluid.

[0065] [Relationship]

[0066] y = y' + (k * a * r * t)

[0067] (Here, y is a control signal value corrected so that the fluid discharge setting amount and the actual fluid discharge amount are equal, y' is a control signal value before the fluid discharge setting amount is corrected, k is a value obtained by multiplying a proportionality constant by the ratio of the internal temperature of the housing in an ideal environment not placed inside the facility to the internal temperature of the housing in a real environment placed inside the facility, a is a value obtained by dividing the control signal value corresponding to the fluctuation amount, which is the difference between the fluid discharge setting amount and the actual fluid discharge amount, by 1°C, r is a percentage value relative to the fluid discharge setting amount, and x is the difference between the expected temperature of the incoming fluid corresponding to the fluid discharge setting amount and the measured actual temperature of the incoming fluid when the internal temperature of the flow control device placed inside the facility is matched to the internal temperature of the first table.)

[0068] Accordingly, the discharge amount of the fluid being discharged is corrected through the internal temperature of the flow control device (100) and the temperature of the fluid flowing into the flow control device (100), and the discharge amount of the fluid is controlled so that the set discharge amount of the fluid and the actual discharged flow rate match each other regardless of the external environment.

[0070] FIG. 2 is a flowchart of a flow rate correction method according to an embodiment of the present invention, FIG. 3 is a graph showing the relationship between the internal temperature and the temperature of the incoming fluid when the flow rate control device is controlled to a first ideal environment temperature in an ideal environment, FIG. 4 is a graph showing the relationship between the internal temperature and the temperature of the incoming fluid when the flow rate control device is controlled to a second ideal environment temperature in an ideal environment, FIG. 5 is a graph regarding the first table, FIG. 6 is a graph showing the relationship between the temperature of the incoming fluid and the fluid flow rate when the flow rate control device is controlled to a first ideal environment temperature in a real environment, FIG. 7 is a graph showing the relationship between the temperature of the incoming fluid and the fluid flow rate when the flow rate control device is controlled to a second ideal environment temperature in a real environment, FIG. 8 is a graph regarding the second table, and FIG. 9 is a graph regarding the third table.

[0071] Hereinafter, a flow rate correction method according to an embodiment of the present invention will be described with reference to FIGS. 1 to 9.

[0072] A flow rate correction method according to one embodiment of the present invention is a method for correcting a flow rate discharged using a flow rate control device (100). A flow rate correction method according to one embodiment of the present invention is a method for correcting a discharged flow rate of a flow rate control device (100) that controls a large flow rate of fluid supplied to equipment (10), such as semiconductor manufacturing equipment, to a preset low flow rate.

[0073] In the following description of the flow rate correction method, an environment in which the fluid discharge setting amount of the flow rate control device (100) and the actual fluid discharge amount of the flow rate control device (100) are constant is the ideal circumstance, and an environment in which the fluid discharge setting amount of the flow rate control device (100) and the actual fluid discharge amount of the flow rate control device (100) are different is the real circumstance.

[0074] The ideal environment is a constant environment in which the conditions of the space where the flow control device (100) is installed do not change, for example, an environment in which the surrounding air of the flow control device (100) circulates and the surrounding temperature of the flow control device (100) is maintained at a constant level.

[0075] The real environment is an environment in which external factors of the flow control device (100) fluctuate, for example, an environment in which the operation of the equipment (i.e., semiconductor device) is stopped and the air inside the equipment (10) is not circulated, so the ambient temperature of the flow control device (100) is not constant, or an environment in which the air inside the equipment (10) is not circulated smoothly even when the equipment (10) is operating, so the ambient temperature of the flow control device (100) is not constant. In the real environment, since the flow rate of the fluid flowing into the flow control device (100) cannot be directly measured, the flow rate of the fluid flowing into the flow control device (100) is controlled based on the flow rate of the fluid discharged from the flow control device (100) in order to control the flow rate of the fluid flowing into the flow control device (100).

[0076] A flow rate correction method according to one embodiment of the present invention comprises the step (S110) of deriving a first table representing the relative ratio of the temperature of a constant environment, the internal temperature of a flow rate control device (100), the temperature of the incoming fluid of the flow rate control device (100), and the flow rate of the incoming fluid in an environment where the fluid discharge setting amount and the actual fluid discharge amount are constant; the step (S120) of deriving a second table representing the relative ratio of the difference between the fluid discharge setting amount of the flow rate control device (100) and the actual fluid discharge amount of the flow rate control device (100), and the difference between the internal temperature of the flow rate control device (100) and the temperature of the incoming fluid in an environment where the fluid discharge setting amount and the actual fluid discharge amount of the flow rate control device (100) are different, using the first table and the second table, so that the actual fluid discharge amount of the flow rate control device (100) becomes equal to the fluid discharge setting amount of the flow rate control device (100); and, in an environment where the fluid discharge setting amount of the flow rate control device (100) and the actual fluid discharge amount of the flow rate control device (100) are different, using the first table and the second table, the actual fluid discharge amount of the flow rate control device (100) It includes a step (S130) of correcting the discharge amount.

[0077] First, a first table is derived in an environment where the fluid discharge setting amount of the flow control device (100) and the actual fluid discharge amount of the flow control device (100) are constant (S110).

[0078] Referring to FIGS. 1 to 3, a flow control device (100) is placed in an ideal environment.

[0079] In the following, an example is described of the case where the ideal environment in which the flow control device (100) is placed to derive the first table is a clean room environment in which the ambient temperature of the flow control device (100) is constant.

[0080] Afterward, the temperature of the abnormal environment (the temperature of the cleanroom) is changed to different temperatures, and the sensor module (130) of the flow control device (100) measures the internal temperature of the housing (110) of the flow control device (100), the temperature of the inflow fluid flowing in through the inflow pipe (121) of the flow control device (100), and the flow rate of the fluid flowing into the inflow pipe (121) at each changed temperature, and the controller (150) of the flow control device (100) receives the measured data and calculates the relative ratio of each of the above-described elements.

[0081] Referring to FIG. 3, the abnormal environment is set to a first abnormal environment temperature, and a first ratio is calculated representing the relative ratio of the difference between the maximum flow rate to the minimum flow rate of the flow control device (100), the internal temperature of the housing (110), and the temperature of the inflow fluid flowing into the inflow pipe (121).

[0082] An abnormal environment set to the first abnormal environment temperature may have an internal temperature that is equal to or lower than the first abnormal environment temperature. In calculating the first ratio, a first sensor (131) installed in the housing (110) measures the internal temperature of the abnormal environment in order to accurately measure the internal temperature of the abnormal environment.

[0083] Next, within an abnormal environment (clean room) set to the first abnormal environment temperature, the first internal temperature is measured through the second sensor (132).

[0084] Next, the controller (150) of the flow rate control device (100) is set so that a first flow rate of fluid is discharged from the discharge pipe (123), and the third sensor (133) of the flow rate control device (100) measures the first inflow temperature of the inflow fluid flowing into the flow rate control device (100) through the inflow pipe (121). The case where the first flow rate is 20% of the maximum flow rate of fluid that the flow rate control device (100) can receive is described as an example.

[0085] Next, the difference between the first internal temperature inside the housing (110) measured through the first sensor (131) and the first inflow temperature of the inflow fluid measured through the third sensor (133), and the relative ratio of the first flow rate flowing into the inflow pipe (121) are calculated. The controller (150) calculates the 1-1 ratio by calculating the ratio of the first internal temperature, the first inflow temperature, and the first flow rate. The above-described first internal temperature is affected by the temperature of the abnormal environment, and the first internal temperature can be determined by the first abnormal environment temperature, which is the temperature of the abnormal environment.

[0086] Afterwards, the discharge of fluid discharged at the first flow rate from the flow rate control device (100) is stopped.

[0087] Next, the controller (150) is configured to discharge a second fluid flow rate having a flow rate value different from the first fluid flow rate, and the third sensor (133) measures the second inflow temperature of the inflow fluid flowing into the flow control device (100) through the inflow pipe (121). The second fluid flow rate is exemplarily described as being 60% of the maximum fluid flow rate that the flow control device (100) can receive.

[0088] Next, the difference between the first internal temperature measured by the first sensor (131) and the second inflow temperature of the inflow fluid measured through the third sensor (133), and the relative ratio of the second flow rate are calculated. The controller (150) calculates the first-2 ratio by calculating the difference between the first internal temperature and the second inflow temperature and the ratio of the second flow rate.

[0089] Afterwards, the discharge of fluid discharged at the second flow rate from the flow rate control device (100) is stopped.

[0090] Next, the controller (150) is configured to discharge a third fluid flow rate having a flow rate value different from that of the first and second fluid flow rates, and the third sensor (133) measures the third inflow temperature of the inflow fluid flowing into the flow control device (100) through the inflow pipe (121). The third fluid flow rate is exemplarily described as being 80% of the maximum fluid flow rate that the flow control device (100) can receive.

[0091] Next, the difference between the first internal temperature measured by the first sensor (131) and the third inflow temperature of the inflow fluid measured through the third sensor (133), and the relative ratio of the third flow rate are calculated. The controller (150) calculates the first-third ratio by calculating the difference between the first internal temperature and the third inflow temperature and the ratio of the third flow rate.

[0092] Afterwards, the discharge of fluid discharged at the third flow rate from the flow rate control device (100) is stopped.

[0093] When the 1-1 ratio, the 1-2 ratio, and the 1-3 ratio are calculated, the controller (150) calculates a first ratio representing the relative ratio of the difference between the internal temperature of the housing (110) and the temperature of the incoming fluid, using the 1-1 ratio, the 1-2 ratio, and the 1-3 ratio, which are proportional to each other at a constant rate, to the maximum flow rate or minimum flow rate of the fluid that the flow control device (100) can receive. The controller (150) calculates the first ratio and creates a graph regarding the first ratio shown in FIG. 3.

[0094] Referring to FIG. 4, the abnormal environment is set to a second abnormal environment temperature, and a second ratio is calculated representing the relative ratio of the difference between the maximum flow rate to the minimum flow rate of the flow control device (100), the internal temperature of the housing (110), and the temperature of the incoming fluid flowing into the inflow pipe (121).

[0095] An abnormal environment set to a second abnormal environment temperature may have an internal temperature that is equal to or lower than the second abnormal environment temperature. In calculating the second ratio, a first sensor (131) installed in the housing (110) re-measures the internal temperature of the abnormal environment in order to accurately measure the internal temperature of the abnormal environment.

[0096] Next, within the abnormal environment (clean room) set to the second abnormal environment temperature, the second internal temperature is measured through the second sensor (132).

[0097] Next, the controller (150) of the flow rate control device (100) is set so that a first flow rate of fluid is discharged from the discharge pipe (123), and the third sensor (133) of the flow rate control device (100) measures the fourth inflow temperature of the inflow fluid flowing into the flow rate control device (100) through the inflow pipe (121).

[0098] Next, the difference between the second internal temperature inside the housing (110) measured by the first sensor (131) and the fourth inflow temperature of the inflow fluid measured by the third sensor (133), and the relative ratio of the first flow rate flowing into the inflow pipe (121) are calculated. The controller (150) calculates the 2-1 ratio by calculating the ratio of the difference between the second internal temperature and the fourth inflow temperature and the first flow rate.

[0099] Afterwards, the discharge of fluid discharged at the first flow rate from the flow rate control device (100) is stopped.

[0100] Next, the controller (150) sets the second flow rate of fluid to be discharged from the discharge pipe (123), and the third sensor (133) measures the fifth inflow temperature of the inflow fluid flowing into the flow control device (100) through the inflow pipe (121).

[0101] Next, the difference between the second internal temperature measured by the first sensor (131) and the fifth inflow temperature of the inflow fluid measured through the third sensor (133), and the relative ratio of the second flow rate are calculated. The controller (150) calculates the second-to-second ratio by calculating the difference between the second internal temperature and the fifth inflow temperature and the ratio of the second flow rate.

[0102] Afterwards, the discharge of fluid discharged at the second flow rate from the flow rate control device (100) is stopped.

[0103] Next, the controller (150) sets the discharge pipe (123) to discharge a third flow rate of fluid, and the third sensor (133) measures the sixth inflow temperature of the inflow fluid flowing into the flow control device (100) through the inflow pipe (121).

[0104] Next, the difference between the second internal temperature measured by the first sensor (131) and the sixth inflow temperature of the inflow fluid measured through the third sensor (133), and the relative ratio of the third flow rate are calculated. The controller (150) calculates the second-third ratio by calculating the difference between the second internal temperature and the sixth inflow temperature and the ratio of the third flow rate.

[0105] Afterwards, the discharge of fluid discharged at the third flow rate from the flow rate control device (100) is stopped.

[0106] When the 2-1 ratio, the 2-2 ratio, and the 2-3 ratio are calculated, the controller (150) calculates a second ratio representing the relative ratio of the difference between the internal temperature of the housing (110) and the temperature of the incoming fluid, using the 2-1 ratio, the 2-2 ratio, and the 2-3 ratio, which are proportional to each other at a constant rate, to the maximum flow rate or minimum flow rate of the fluid that the flow control device (100) can receive. The controller (150) calculates the second ratio and creates a graph regarding the second ratio shown in FIG. 4.

[0107] In one embodiment of the present invention, to calculate the first ratio and the second ratio, the fluid discharge setting amount is set to the first flow rate to the third flow rate to calculate the first ratio and the second ratio, but the first ratio and the second ratio may also be calculated by setting a plurality of flow rates with a predetermined difference of 10% based on the maximum flow rate of fluid that the flow rate control device (100) can receive.

[0108] When the first ratio and the second ratio are calculated, the controller (150) derives the first table by using the respective measured multiple relative ratios (first ratio and second ratio) at different temperatures (first abnormal environment temperature and second abnormal environment temperature) to derive the relative ratios for all temperatures between the minimum temperature (e.g., first abnormal environment temperature) and the maximum temperature (e.g., second abnormal environment temperature) among the different temperatures (first abnormal environment temperature and second abnormal environment temperature).

[0109] Referring to FIG. 5, the controller (150) interpolates the first ratio and the second ratio to indirectly derive the relative ratios for the difference between the internal temperature of the housing (110) and the temperature of the incoming fluid, and the maximum flow rate to minimum flow rate of the flow control device (100) for the entire range of the first abnormal environment temperature to the second abnormal environment temperature. When the controller (150) indirectly derives the ratios for each element, a first table (see FIG. 5) is produced, which is a table of relative ratios for the difference between the internal temperature of the housing (110) and the temperature of the incoming fluid, and the maximum flow rate to minimum flow rate of the flow control device (100) for the range of the first abnormal environment temperature to the second abnormal environment temperature.

[0110] Next, a second table is derived in an environment where the fluid discharge setting amount of the flow control device (100) and the actual fluid discharge amount of the flow control device (100) are different (S120).

[0111] When the first table is calculated, the flow control device (100) moves out of the ideal environment and is placed in the real environment.

[0112] In the following, to derive the second table, an example is given in which the actual environment in which the flow control device (100) is placed is the interior of a facility (10) that has ceased operation. Since the operation of the facility (i.e., semiconductor manufacturing equipment) has ceased, the air inside the facility (10) is not circulated, so the environment may be one in which the ambient temperature of the flow control device (100) is not constant.

[0113] Afterward, the temperature of the real environment is changed to different temperatures, and the sensor module (130) measures the difference between the fluid discharge setting amount and the actual fluid discharge amount at each temperature, and the difference between the internal temperature of the housing (110) and the temperature of the incoming fluid flowing into the inlet pipe (121), and the controller (150) calculates the relative ratio of each element using the data regarding the specified difference values.

[0114] Referring to FIG. 6, the real environment is set to the first real environment temperature, and a third ratio is calculated representing the relative ratio of the difference between the expected temperature of the inflow fluid confirmed through the first table and the actual temperature of the inflow fluid actually measured in the inflow pipe (121), and the fluctuation amounts of the maximum and minimum flow rates of the flow control device (100).

[0115] The real environment set to the first real environment temperature may have an internal temperature that is the same as or lower than the first real environment temperature. In calculating the third ratio, in order to accurately measure the internal temperature of the real environment, the first sensor (131) installed in the housing (110) measures the internal temperature of the real environment (i.e., the internal temperature of the non-operating equipment (10).

[0116] Next, in a real environment set to a second ideal environment temperature, a third internal temperature, which is the internal atmosphere temperature of the housing (110), is measured through the second sensor (132).

[0117] Next, the controller (150) of the flow rate control device (100) sets the first flow rate of fluid to be discharged from the discharge pipe (123). Afterward, the controller (150) matches the measured third internal temperature to the internal temperature of the first table corresponding to the numerical value (i.e., temperature value) of the third internal temperature based on the first table. Afterward, the controller (150) checks the first expected temperature of the incoming fluid corresponding to the first flow rate based on the internal temperature corresponding to the numerical value of the third internal temperature in the first table.

[0118] For example, if the third internal temperature is measured at 49.5°C and the controller (150) is set so that the fluid of the first flow rate is 20%, then point A corresponding to the internal temperature of 49.5°C for the first flow rate of 20% is identified in the first table as shown in FIG. 5.

[0119] With point A confirmed, the first real environment temperature, where the third internal temperature is measured, is constant and the flow rate of the discharged fluid is equal to the flow rate of the incoming fluid; therefore, the first predicted temperature of the incoming fluid may be point B, which corresponds to 20% of the flow rate of the incoming fluid (i.e., the same flow rate as the first flow rate) while the x-axis (i.e., the ideal environment temperature, which is a variable corresponding to the first real environment temperature) is the same. Thus, it can be confirmed that the first predicted temperature is 21.5℃.

[0120] Next, the third sensor (133) measures the first actual temperature of the incoming fluid. The controller (150) receives the measurement value from the third sensor (133) and calculates a first difference value, which is the difference between the measured first actual temperature and the first predicted temperature that was previously checked.

[0121] Next, the fourth sensor (134) measures the actual fluid discharge amount. The controller (150) receives the measurement value measured by the fourth sensor (134) and calculates a first variation amount, which is the difference between the measured actual fluid discharge amount and the fluid discharge set amount (i.e., the first flow rate).

[0122] Next, the controller (150) calculates a third-1 ratio representing the relative ratio of the calculated first difference value and the first variation amount.

[0123] Afterwards, the discharge of fluid discharged at the first flow rate from the flow rate control device (100) is stopped.

[0124] Next, the controller (150) is configured to discharge a second flow rate fluid having a flow rate value different from the first flow rate. An example is given where the second flow rate is 60% of the maximum flow rate of fluid that the flow rate control device (100) can receive.

[0125] Subsequently, the controller (150) matches the measured third internal temperature to the internal temperature of the first table corresponding to the third internal temperature value (i.e., temperature value) based on the first table. Subsequently, the controller (150) checks the second expected temperature of the inflow fluid corresponding to the second flow rate based on the internal temperature corresponding to the third internal temperature in the first table.

[0126] For example, if the third internal temperature is measured at 49.5°C and the controller (150) is set so that the fluid of the first flow rate is 60%, then, as shown in FIG. 5, point C corresponding to the internal temperature of 49.5°C for the first flow rate of 60% is identified in the first table.

[0127] With point C confirmed, the first real environment temperature, where the third internal temperature is measured, is constant and the flow rate of the discharged fluid is equal to the flow rate of the incoming fluid; therefore, the second predicted temperature of the incoming fluid may be point D, which corresponds to 60% of the flow rate of the incoming fluid (i.e., the same flow rate as the second flow rate), while the x-axis (i.e., the ideal environment temperature, which is a variable corresponding to the first real environment temperature) is the same. Thus, it can be confirmed that the second predicted temperature is 21.0℃.

[0128] Next, the third sensor (133) measures the second actual temperature of the incoming fluid. The controller (150) receives the measurement value from the third sensor (133) and calculates a second difference value, which is the difference between the measured second actual temperature and the second predicted temperature that was previously checked.

[0129] Next, the fourth sensor (134) measures the actual fluid discharge amount. The controller (150) receives the measurement value measured by the fourth sensor (134) and calculates a second variation amount, which is the difference between the measured actual fluid discharge amount and the fluid discharge set amount (i.e., the first flow rate).

[0130] Next, the controller (150) calculates a third-2 ratio representing the relative ratio of the calculated second difference value and the second variation amount.

[0131] Afterwards, the discharge of fluid discharged at the first flow rate from the flow rate control device (100) is stopped.

[0132] When the 3-1 ratio and the 3-2 ratio are calculated, the controller (150) uses the 3-1 ratio and the 3-2, which are in constant proportion to each other, to calculate a 3 ratio representing the relative ratio of the difference between the expected temperature of the incoming fluid and the actual measured temperature, and the fluctuation amounts of the maximum flow rate and minimum flow rate of the fluid that the flow control device (100) can receive. The controller (150) calculates the 3 ratio and creates a graph of the 3 ratio shown in FIG. 6.

[0133] Referring to FIG. 7, the real environment is set to the second real environment temperature, and a fourth ratio is calculated representing the relative ratio of the difference between the expected temperature of the inflow fluid confirmed through the first table and the actual temperature of the inflow fluid actually measured in the inflow pipe (121), and the fluctuation amounts of the maximum and minimum flow rates of the flow control device (100).

[0134] The real environment set to the second real environment temperature may have an internal temperature that is the same as or lower than the second real environment temperature. In calculating the fourth ratio, in order to accurately measure the internal temperature of the real environment, the first sensor (131) installed in the housing (110) measures the internal temperature of the real environment.

[0135] Next, within an environment set to a second ideal environment temperature, a fourth internal temperature, which is the internal atmosphere temperature of the housing (110), is measured through the second sensor (132).

[0136] Next, the controller (150) of the flow rate control device (100) sets the first flow rate of fluid to be discharged from the discharge pipe (123). Afterwards, the controller (150) matches the measured fourth internal temperature to the internal temperature of the first table corresponding to the value (i.e., temperature value) of the fourth internal temperature based on the first table. Afterwards, the controller (150) checks the third expected temperature of the incoming fluid corresponding to the first flow rate based on the internal temperature corresponding to the value of the fourth internal temperature in the first table.

[0137] Next, the third sensor (133) measures the third actual temperature of the incoming fluid. The controller (150) receives the measurement value from the third sensor (133) and calculates a third difference value, which is the difference between the measured third actual temperature and the previously confirmed third expected temperature.

[0138] Next, the fourth sensor (134) measures the actual fluid discharge amount. The controller (150) receives the measurement value measured by the fourth sensor (134) and calculates a third variation amount, which is the difference between the measured actual fluid discharge amount and the fluid discharge set amount (i.e., the first flow rate).

[0139] Next, the controller (150) calculates a 4-1 ratio representing the relative ratio of the calculated 3rd difference value and the 3rd variation amount.

[0140] Afterwards, the discharge of fluid discharged at the first flow rate from the flow rate control device (100) is stopped.

[0141] Next, the controller (150) sets the fluid of a second flow rate, which has a flow rate value different from the first flow rate, to be discharged.

[0142] Subsequently, the controller (150) matches the measured fourth internal temperature to the internal temperature of the first table corresponding to the fourth internal temperature value (i.e., temperature value) based on the first table. Subsequently, the controller (150) checks the fourth expected temperature of the inflow fluid corresponding to the second flow rate based on the internal temperature corresponding to the fourth internal temperature in the first table.

[0143] Next, the third sensor (133) measures the fourth actual temperature of the incoming fluid. The controller (150) receives the measurement value from the third sensor (133) and calculates a fourth difference value, which is the difference between the measured fourth actual temperature and the previously confirmed fourth expected temperature.

[0144] Next, the fourth sensor (134) measures the actual fluid discharge amount. The controller (150) receives the measurement value measured by the fourth sensor (134) and calculates a fourth variation amount, which is the difference between the measured actual fluid discharge amount and the fluid discharge set amount (i.e., the first flow rate).

[0145] Next, the controller (150) calculates a 4-2 ratio representing the relative ratio of the calculated 4th difference value and the 4th variation amount.

[0146] Afterwards, the discharge of fluid discharged at the second flow rate from the flow rate control device (100) is stopped.

[0147] When the 4-1 ratio and the 4-2 ratio are calculated, the controller (150) uses the 4-1 ratio and the 3-2 ratio, which are in constant proportion to each other, to calculate a 4 ratio representing the relative ratio of the difference between the expected temperature of the incoming fluid and the actual measured temperature, and the fluctuation amounts of the maximum flow rate and minimum flow rate of the fluid that the flow control device (100) can receive. The controller (150) calculates the 4 ratio and creates a graph of the 4 ratio shown in FIG. 7.

[0148] In one embodiment of the present invention, to calculate the third ratio and the fourth ratio, the fluid discharge setting amount was set to the first flow rate and the second flow rate to calculate the third ratio and the fourth ratio, but the third ratio and the fourth ratio may also be calculated by setting a plurality of flow rates with a predetermined difference of 10% based on the maximum flow rate of fluid that the flow rate control device (100) can receive.

[0149] When the third ratio and the fourth ratio are calculated, the controller (150) derives the second table by using the respective measured multiple relative ratios (third ratio and fourth ratio) at different temperatures (first real environment temperature and second real environment temperature) to derive the relative ratios for all temperatures between the minimum temperature (first real environment temperature) and the maximum temperature (second real environment temperature) among the different temperatures (first real environment temperature and second real environment temperature).

[0150] Referring to FIG. 8, the controller (150) interpolates the third ratio and the fourth ratio to indirectly derive the relative ratio of the difference between the expected temperature of the incoming fluid and the measured actual temperature of the incoming fluid, and the amount of variation of each of the maximum flow rate to the minimum flow rate of the flow control device (100) for the entire range of the first and second real environment temperatures. When the controller (150) indirectly derives the ratios for each element, a second table (see FIG. 8) is produced, which is a table of the relative ratios between the difference between the expected temperature of the incoming fluid and the measured actual temperature of the incoming fluid, and the amounts of variation of each of the first and second real environment temperatures and the maximum and minimum flow rates of the flow control device (100).

[0151] Afterwards, in an environment where the fluid discharge setting amount and the fluid actual discharge amount are different, the actual discharge amount of the fluid discharged by the fluid control device (100) is corrected using the first table and the second table so that the actual discharge amount of the fluid of the flow control device (100) becomes equal to the fluid discharge setting amount of the flow control device (100) (S130).

[0152] First, the flow control device (100) is placed in an environment where the fluid discharge setting amount and the actual fluid discharge amount are different. Below, an example is described of the environment in which the flow control device is placed (an environment where the fluid discharge setting amount and the actual fluid discharge amount are different), as shown in FIG. 2, in which the facility (10) is operated but the air inside the facility (10) does not circulate smoothly, and the ambient temperature of the flow control device (100) is not constant.

[0153] Subsequently, the controller (150) sets the fluid discharge setting amount of the flow control device (100). The controller (150) transmits a control signal value (hereinafter referred to as the initial control signal value) that matches the above-described fluid discharge setting amount to a valve (124) that controls the diameter of the inlet pipe (121) so that the set fluid discharge setting amount is discharged.

[0154] Afterward, the controller (150) measures the actual fluid discharge amount using the third sensor (133) and determines whether the actual fluid discharge amount is the same as the set fluid discharge amount.

[0155] If it is determined that the actual fluid discharge amount is not the same as the set fluid discharge amount, the controller (150) corrects the actual fluid discharge amount.

[0156] The controller (150) calculates a control signal value (hereinafter referred to as a corrected control signal value) for controlling the amount of inflow of the inflow fluid through the following relationship.

[0157] y = y' + (k * a * r * x)

[0158] (Here, y is a control signal value corrected so that the fluid discharge setting amount and the actual fluid discharge amount are equal, y' is the initial control signal value before the fluid discharge setting amount is corrected, k is a value obtained by multiplying a proportionality constant by the ratio of the internal temperature of the flow control device in an environment where the fluid discharge setting amount and the actual fluid discharge amount are constant to the internal temperature of the flow control device in an environment where the fluid discharge setting amount and the actual fluid discharge amount are different, a is a value obtained by dividing the control signal value corresponding to the fluctuation amount by 1°C, r is a percentage value relative to the fluid discharge setting amount, and x is the difference between the expected temperature of the incoming fluid corresponding to the fluid discharge setting amount and the measured actual temperature of the incoming fluid when the internal temperature of the flow control device in an environment where the fluid discharge setting amount and the actual fluid discharge amount are different is matched to the internal temperature of the first table.)

[0159] In the process of calculating the correction control signal value, when using a relationship equation, in order to derive a, which is a control signal value corresponding to the amount of fluid fluctuation, the correction control signal value corresponding to the amount of fluctuation is identified by referring to the third table (see FIG. 9), which is a table of the control signal value of the flow rate control device (100) and the pre-set amount of fluctuation of the flow rate control device (100), in an environment where the fluid discharge setting amount and the actual fluid discharge amount are constant. The third table is a table illustrating the correlation between the amount of fluctuation (and fluid flow rate) and the control signal value used by the flow rate control device (100) to calculate the initial control signal value.

[0160] The controller (150) transmits the confirmed correction control signal value to the valve (124) and drives the valve (124) to adjust the diameter inside the inlet pipe (121). Accordingly, the controller (150) controls the valve (124) so ​​that the fluid actual discharge amount of the flow control device (100) is discharged to the amount of the fluid set discharge amount initially set.

[0162] Although embodiments of the present invention have been described in more detail with reference to the attached drawings, the present invention is not necessarily limited to these embodiments and may be modified in various ways within the scope of the technical spirit of the present invention. Accordingly, the embodiments disclosed in the present invention are intended to explain, not to limit, the technical spirit of the present invention, and the scope of the technical spirit of the present invention is not limited by these embodiments. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. The scope of protection of the present invention shall be interpreted by the claims below, and all technical spirits within the equivalent scope shall be interpreted as being included within the scope of rights of the present invention. Explanation of the symbols

[0163] 100: Flow control device 110: Fluid piping 120: Sensor module 130: Cooling element 140: Controller

Claims

Claim 1 A method for correcting a flow rate discharged using a flow rate control device, comprising: a step in which, in an ideal circumstance where a fluid discharge setting amount and an actual fluid discharge amount match, a controller of the flow rate control device derives a first table representing the relative ratio of the temperature of the ideal circumstance, the internal temperature of the flow rate control device, the temperature of the incoming fluid of the flow rate control device, and the flow rate of the incoming fluid; a step in which, in a real circumstance where a fluid discharge setting amount and an actual fluid discharge amount differ, a controller derives a second table representing the relative ratio of the temperature of the real circumstance, the difference value between the fluid discharge setting amount and the actual fluid discharge amount, and the difference value between the internal temperature and the temperature of the incoming fluid; and a step in which, in the real circumstance, a controller corrects the actual fluid discharge amount using the first table and the second table so that the actual fluid discharge amount becomes equal to the fluid discharge setting amount. Claim 2 In claim 1, the step of correcting the actual fluid discharge amount is a flow rate correction method for calculating a control signal value for controlling the inflow amount of the inflow fluid through the following relationship: [Relationship] y = y' + (k * a * r * x) (wherein y is a control signal value corrected so that the fluid discharge setting amount and the actual fluid discharge amount become equal, y' is a control signal value before the fluid discharge setting amount is corrected, k is a value obtained by multiplying a proportionality constant by the ratio of the internal temperature of the flow rate control device in an ideal environment to the internal temperature of the flow rate control device in a different real environment, a is a value obtained by dividing the control signal value corresponding to the fluctuation amount by 1°C, r is a percentage value relative to the fluid discharge setting amount, and x is the difference between the expected temperature of the inflow fluid corresponding to the fluid discharge setting amount and the measured actual temperature of the inflow fluid when the internal temperature of the flow rate control device in the real environment is matched to the internal temperature of the first table.) Claim 3 A flow rate correction method according to claim 1, wherein the step of deriving the first table comprises: a step of placing the flow rate control device within the ideal circumstance; a step of changing the temperature of the ideal circumstance to different temperatures and measuring the internal temperature, the temperature of the incoming fluid, and the flow rate of the fluid at each of the different temperatures to calculate a relative ratio; and a step of deriving relative ratios for all temperatures between the minimum temperature and the maximum temperature among the different temperatures using a plurality of relative ratios measured at each of the different temperatures. Claim 4 A flow rate correction method according to claim 3, wherein the step of calculating the relative ratio comprises: a step of calculating a first ratio representing a relative ratio regarding the difference between the internal temperature and the temperature of the incoming fluid, by setting the abnormal environment to a first abnormal environment temperature; and a step of calculating a second ratio representing a relative ratio regarding the difference between the internal temperature and the temperature of the incoming fluid, by setting the abnormal environment to a second abnormal environment temperature; and the step of deriving the relative ratios comprises: a step of interpolating the first ratio and the second ratio to each other to calculate the first table, which is a table of relative ratios regarding the difference between the internal temperature and the temperature of the incoming fluid, and the maximum flow rate to the minimum flow rate of the flow rate control device. Claim 5 In claim 4, the step of calculating the first ratio comprises the step of measuring the first internal temperature of the flow control device at the first ideal environment temperature; A step of setting the flow control device to discharge a first flow rate fluid and measuring a first inlet temperature of the inlet fluid flowing into the flow control device; a step of calculating a 1-1 ratio representing the relative ratio of the first flow rate and the difference between the first internal temperature and the first inlet temperature; a step of setting the flow control device to discharge a second flow rate fluid and measuring a second inlet temperature of the inlet fluid flowing into the flow control device; a step of calculating a 1-2 ratio representing the relative ratio of the second flow rate and the difference between the first internal temperature and the second inlet temperature; a step of setting the flow control device to discharge a third flow rate fluid and measuring a third inlet temperature of the inlet fluid flowing into the flow control device; a step of calculating a 1-3 ratio representing the relative ratio of the third flow rate and the difference between the first internal temperature and the third inlet temperature; and using the 1-1 ratio, the 1-2 ratio, and the 1-3 ratio which are constantly proportional to each other, the maximum flow rate to the minimum flow rate of the flow control device and the internal temperature and the A flow rate correction method comprising the step of calculating the first ratio representing the relative ratio of the temperature difference value of the incoming fluid. Claim 6 In claim 4, the step of calculating the second ratio comprises: measuring the second internal temperature of the flow control device at the second abnormal environment temperature; setting the flow control device to discharge a first flow rate fluid and measuring the fourth inlet temperature of the inlet fluid flowing into the flow control device; calculating the difference between the second internal temperature and the fourth inlet temperature and the second-1 ratio representing the relative ratio of the first flow rate; setting the flow control device to discharge a second flow rate fluid and measuring the fifth inlet temperature of the inlet fluid flowing into the flow control device; calculating the difference between the second internal temperature and the fifth inlet temperature and the second-2 ratio representing the relative ratio of the second flow rate; setting the flow control device to discharge a third flow rate fluid and measuring the sixth inlet temperature of the inlet fluid flowing into the flow control device; calculating the difference between the second internal temperature and the sixth inlet temperature and the second-3 ratio representing the relative ratio of the third flow rate; and the second-1 which are constantly proportional to each other A flow rate correction method comprising the step of calculating the second ratio, which represents the relative ratio of the difference between the internal temperature and the temperature of the incoming fluid, using the ratio, the second-2 ratio, and the third-2 ratio. Claim 7 A flow rate correction method according to claim 3, wherein the step of deriving the second table comprises: a step of placing the flow rate control device within the real circumstance; a step of changing the temperature of the real circumstance to different temperatures and, at each temperature, measuring the difference between the fluid discharge setting amount and the actual fluid discharge amount, and the difference between the internal temperature and the temperature of the incoming fluid to calculate a relative ratio; and a step of deriving relative ratios for all temperatures between the minimum temperature and the maximum temperature among the different temperatures using a plurality of relative ratios measured at each of the different temperatures. Claim 8 A flow rate correction method according to claim 7, wherein the step of calculating the relative ratio comprises: a step of setting the real environment to a first real environment temperature and calculating a third ratio representing the relative ratio of the difference between the expected temperature of the inflow fluid confirmed through the first table and the actual temperature of the inflow fluid measured, wherein the real environment is set to a second real environment temperature and the difference between the expected temperature of the inflow fluid confirmed through the first table and the actual temperature of the inflow fluid measured, wherein the real environment is set to a second real environment temperature and calculating a fourth ratio representing the relative ratio of the difference between the expected temperature of the inflow fluid measured through the first table and the difference between the expected temperature of the inflow fluid measured, wherein the step of deriving the relative ratios comprises: a step of interpolating the third ratio and the fourth ratio to each other to calculate the second table, which is a table of relative ratios for the difference between the expected temperature of the inflow fluid and the actual temperature of the inflow fluid measured, wherein the difference between the first real environment temperature and the second real environment temperature, the variation between the maximum flow rate and the minimum flow rate of the flow control device, and the actual temperature of the inflow fluid measured. Claim 9 In claim 8, the step of calculating the third ratio comprises: measuring the third internal temperature in the first real environment; and setting the flow control device to discharge a fluid of the first flow rate, and based on the state in which the third internal temperature is matched to the corresponding internal temperature in the first table, confirming the first expected temperature of the incoming fluid corresponding to the first flow rate. A step of measuring a first actual temperature of the incoming fluid and calculating a first difference value between the measured first actual temperature and the first expected temperature; a step of measuring the actual discharge amount of the fluid and calculating a first fluctuation amount which is the difference between the measured actual discharge amount of the fluid and the first flow rate; a step of calculating a 3-1 ratio representing the relative ratio between the first difference value and the first fluctuation amount; a step of setting the flow rate control device to discharge a fluid of a second flow rate and, based on the state where the third internal temperature is matched to the corresponding internal temperature in the first table, confirming the second expected temperature of the incoming fluid corresponding to the second flow rate; a step of measuring the second actual temperature of the incoming fluid and calculating a second difference value between the measured second actual temperature and the second expected temperature; a step of re-measuring the actual discharge amount of the fluid and calculating a second fluctuation amount which is the difference between the re-measured actual discharge amount of the fluid and the second flow rate; a step of calculating a 3-2 ratio representing the relative ratio between the second difference value and the second fluctuation amount; the 3-1 which is constantly proportional to each other A flow rate correction method comprising the step of calculating the third ratio, which represents the relative ratio of the difference between the expected temperature and the measured actual temperature, and the fluctuation amounts of each of the maximum flow rate to the minimum flow rate of the flow rate control device, using the ratio and the third-2 ratio. Claim 10 In claim 8, the step of calculating the fourth ratio comprises: measuring the fourth internal temperature in the second real environment; and setting the flow control device to discharge a fluid of the first flow rate, and based on the state in which the fourth internal temperature is matched to the corresponding internal temperature in the first table, confirming the third expected temperature of the incoming fluid corresponding to the first flow rate. A step of measuring the third actual temperature of the incoming fluid and calculating a third difference value between the measured third actual temperature and the third predicted temperature; a step of measuring the actual discharge amount of the fluid and calculating a third fluctuation amount, which is the difference between the measured actual discharge amount of the fluid and the first flow rate; a step of calculating a 4-1 ratio representing the relative ratio between the third difference value and the third fluctuation amount; a step of setting the flow rate control device to discharge a fluid of the second flow rate and, based on the state where the fourth internal temperature is matched to the corresponding internal temperature in the first table, confirming the fourth predicted temperature of the incoming fluid corresponding to the second flow rate; a step of measuring the fourth actual temperature of the incoming fluid and calculating a fourth difference value between the measured fourth actual temperature and the fourth predicted temperature; a step of re-measuring the actual discharge amount of the fluid and calculating a fourth fluctuation amount, which is the difference between the re-measured actual discharge amount of the fluid and the second flow rate; a step of calculating a 4-2 ratio representing the relative ratio between the fourth difference value and the fourth fluctuation amount; the 4-1 which is constantly proportional to each other A flow rate correction method comprising the step of calculating the fourth ratio, which represents the relative ratio of the difference between the expected temperature and the measured actual temperature, and the fluctuation amounts of each of the maximum flow rate to the minimum flow rate of the flow rate control device, using the ratio and the fourth-2 ratio. Claim 11 A flow rate correction method according to claim 2, wherein the step of correcting the actual fluid discharge amount comprises deriving a, which is a control signal value corresponding to the fluid fluctuation amount in the relationship, by using a third table which is a table of the control signal value of the flow rate control device and the preset fluctuation amount of the flow rate control device in the abnormal environment to confirm the control signal value corresponding to the fluctuation amount. Claim 12 A flow rate control device comprising: a housing; a fluid pipe installed inside the housing and having an inlet pipe for introducing fluid and a discharge pipe for discharging fluid; a cooling element coupled to the fluid pipe and for cooling the fluid passing through the fluid pipe; a sensor module for measuring the external temperature of the housing, the internal temperature of the housing, the temperature of the inlet fluid entering the housing, and the flow rate of the discharged fluid; and a controller connected to the sensor module and correcting the fluid discharge amount using a first table representing the relative ratio of the internal temperature, the temperature of the inlet fluid, and the flow rate of the inlet fluid derived in an ideal circumstance where the fluid discharge setting amount and the actual fluid discharge amount match, and a second table representing the relative ratio of the difference between the fluid discharge setting amount and the actual fluid discharge amount and the difference between the internal temperature and the temperature of the inlet fluid derived in a real circumstance where the fluid discharge setting amount and the actual fluid discharge amount differ. Claim 13 In claim 12, the housing is provided inside a facility that uses a fluid, and the sensor module includes a first sensor installed in the housing and measuring the temperature of the facility, a second sensor installed in the housing and measuring the internal temperature of the housing, a third sensor installed in the inlet pipe and measuring the temperature of the inlet fluid, and a fourth sensor installed in the discharge pipe and measuring the flow rate of the discharged fluid, and the controller is a flow rate control device that receives signals from the first to the fourth sensors and controls the degree of opening of the inlet pipe using the received signals. Claim 14 A flow control device according to claim 13, wherein the fluid pipe comprises a valve that controls the internal diameter into which the fluid flows; and the controller generates a corrected control signal value through the following relationship and controls the valve with the corrected control signal value so that the actual discharge amount of the fluid in the discharge pipe becomes equal to the fluid discharge setting amount. [Relationship] y = y' + (k * a * r * x) (wherein y is a control signal value corrected so that the fluid discharge setting amount and the actual discharge amount of the fluid become equal, y' is a control signal value before the fluid discharge setting amount is corrected, k is a value obtained by multiplying a proportionality constant by the ratio of the internal temperature of the housing in an ideal environment not placed inside the facility and the internal temperature of the housing in a real environment placed inside the facility, a is a value obtained by dividing the control signal value corresponding to the fluctuation amount, which is the difference between the fluid discharge setting amount and the fluid actual discharge amount, by 1°C, r is a percentage value relative to the fluid discharge setting amount, and x is placed inside the facility It is the difference between the expected temperature of the incoming fluid corresponding to the fluid discharge setting amount and the measured actual temperature of the incoming fluid, when the internal temperature of the flow control device is matched to the internal temperature of the first table.

Images