Solenoid valve control mechanism and solenoid valve control method

Abstract

To keep a good responsiveness of an open / close control of an electromagnetic valve following a secondary pressure while making a good control of the fluctuation of the secondary pressure, when feedback-controlling the electromagnetic valve for opening / closing a gas pipe for distributing gas based on the secondary side pressure of the electromagnetic valve.SOLUTION: A control device performs an electromagnetic-valve open / close control, in which an electromagnetic valve is in a close state when an open / close control index for a secondary pressure measured by a secondary pressure measuring unit is over a prescribed secondary pressure upper limit threshold, and is in an open state when the index is less than a prescribed secondary pressure lower limit value. Furthermore, the control device performs an electromagnetic-valve open / close suppression control over a prescribed open / close control suppression period after a first switching point at which the electromagnetic valve is switched from the close state to the open state or a second switching point at which it is switched from the open state to the close state, in which opening / closing the electromagnetic valve is suppressed so that the open / close control index is either the secondary pressure just before a switching point or the average value of the secondary pressure during a prescribed period just before the current point.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a solenoid valve control mechanism including a control device for controlling an open / closed state of a solenoid valve that opens and closes a gas flow pipe through which gas flows, and a solenoid valve control method.

Background Art

[0002] Conventionally, a governor as a pressure regulating device has been provided in a gas flow pipe that supplies fuel gas (for example, city gas 13A) to a household or the like where gas-using equipment is installed, in order to control the gas supply pressure to a target pressure (see Patent Document 1). In the pressure regulating device, for example, the secondary pressure, which is the pressure on the secondary side of the pressure regulating device, is transmitted to a pressure regulating chamber provided with a diaphragm, and the opening degree of a main valve body provided in the gas flow pipe and connected to the diaphragm is adjusted by the displacement of the diaphragm caused by the secondary pressure, so that the pressure on the secondary side can be adjusted.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Now, the above-described governor is often used in a gas flow pipe with a medium pressure or higher through which gas of several thousand m 3 N / h flows. However, for example, in a gas flow pipe through which gas with a relatively small flow rate of several tens of m 3 N / h flows, the gas pressure on the secondary side may be controlled by a solenoid valve. In this case, for example, when the secondary pressure becomes less than a predetermined secondary pressure lower threshold value, the solenoid valve is controlled to an open state, and when the secondary pressure exceeds a predetermined secondary pressure upper threshold value, the solenoid valve is controlled to a closed state, so as to control the secondary pressure of the solenoid valve to a predetermined target pressure.

[0005] However, when performing such control, as shown in Figure 2, if the solenoid valve is controlled from a closed state to an open state (or from an open state to a closed state) at a predetermined time ts, the secondary pressure will be disturbed by the stroke of the solenoid valve body over a predetermined period (the period Tf from ts to te in Figure 2). Then, by controlling the opening and closing state of the solenoid valve based on this disturbed secondary pressure, a control malfunction occurs where the secondary pressure oscillates significantly after the predetermined time ts, as shown in Figure 3.

[0006] The present invention has been made in view of the above-mentioned problems, and its object is to provide a solenoid valve control mechanism and a solenoid valve control method that can maintain good responsiveness of opening and closing control of a solenoid valve that follows the secondary pressure while effectively suppressing disturbances in the secondary pressure when feedback control of a solenoid valve that opens and closes a gas pipe through which gas flows based on the pressure on the secondary side of the solenoid valve. [Means for solving the problem]

[0007] The solenoid valve control mechanism for achieving the above objective is: A solenoid valve control mechanism equipped with a control device that controls the open / closed state of a solenoid valve that opens and closes a gas flow pipe through which gas flows, the characteristic configuration of which is: The solenoid valve is equipped with a secondary pressure measuring unit for measuring the secondary pressure on the secondary side, The control device performs solenoid valve opening and closing control such that when the opening / closing control index, which is the secondary pressure measured by the secondary pressure measuring unit, exceeds a predetermined secondary pressure upper threshold, the solenoid valve is closed, and when it falls below a predetermined secondary pressure lower limit, the solenoid valve is opened. From the first switching point, which is the switching point for switching the solenoid valve from the closed state to the open state, or the second switching point, which is the switching point for switching the solenoid valve from the open state to the closed state, solenoid valve opening / closing suppression control is performed to suppress the opening and closing of the solenoid valve for a predetermined opening / closing control suppression period, using either the secondary pressure immediately before the switching point or the average value of the secondary pressure during the predetermined period immediately before the current time as the opening / closing control index. The key feature is that, after the switching point, the amplitude, which is the difference between the maximum and minimum values ​​of the secondary pressure in a predetermined unit time, is derived, and the point in time when this amplitude falls below a predetermined reference amplitude is set as the end of the switching control suppression period.

[0008] A solenoid valve control method for achieving the above objective is: A solenoid valve control method for controlling the open / closed state of a solenoid valve that opens and closes a gas flow pipe through which gas flows, the characteristic configuration thereof is: The solenoid valve opening and closing control is performed such that when the opening and closing control index, which is the secondary pressure measured on the secondary side of the solenoid valve, exceeds a predetermined secondary pressure upper threshold, the solenoid valve is closed, and when it falls below a predetermined secondary pressure lower limit, the solenoid valve is opened. From the first switching point, which is the switching point for switching the solenoid valve from the closed state to the open state, or the second switching point, which is the switching point for switching the solenoid valve from the open state to the closed state, solenoid valve opening / closing suppression control is performed to suppress the opening and closing of the solenoid valve for a predetermined opening / closing control suppression period, using either the secondary pressure immediately before the switching point or the average value of the secondary pressure during the predetermined period immediately before the current time as the opening / closing control index. The key feature is that, after the switching point, the amplitude, which is the difference between the maximum and minimum values ​​of the secondary pressure in a predetermined unit time, is derived, and the point in time when this amplitude falls below a predetermined reference amplitude is set as the end of the switching control suppression period.

[0009] According to the above-described configuration, firstly, when the secondary pressure measured by the secondary pressure measurement unit exceeds a predetermined upper secondary pressure threshold, the solenoid valve is closed, and when it falls below a predetermined lower secondary pressure limit, the solenoid valve is opened. This solenoid valve opening and closing control is performed, thereby controlling the secondary pressure to a target value set between the upper and lower secondary pressure thresholds. However, as mentioned above, this solenoid valve opening and closing control of the secondary pressure results in fluctuations in the secondary pressure. Therefore, in the above-described configuration, after the first switching point, which is the switching point for switching the solenoid valve from a closed state to an open state, or the second switching point, which is the switching point for switching from an open state to a closed state, solenoid valve opening / closing suppression control is performed to suppress the opening and closing of the solenoid valve for a predetermined period of time, by setting the opening / closing control index to either the secondary pressure immediately before the switching point or the average value of the secondary pressure for the predetermined period immediately before the current point, rather than the secondary pressure where the opening / closing control of the solenoid valve is being performed. As a result, even if disturbances in the secondary pressure occur after the switching point when the opening / closing control of the solenoid valve is performed, during the opening / closing control suppression period after the switching point, the opening / closing control index is set to either the secondary pressure immediately before the switching point or the average value of the secondary pressure for the predetermined period immediately before the current point, rather than the secondary pressure where the disturbances are occurring, thereby effectively preventing control failures from occurring after the switching point. Furthermore, with the above-described configuration, compared to a case where the solenoid valve is always controlled using the average value or moving average value of the secondary pressure over a fixed period immediately preceding the present moment as the control indicator, the solenoid valve is controlled in accordance with the secondary pressure except during the control suppression period. Therefore, the responsiveness of the solenoid valve switching to changes in secondary pressure can be improved. Based on the above, it is possible to realize a solenoid valve control mechanism and a solenoid valve control method that, when feedback-controlled based on the pressure on the secondary side of a solenoid valve that opens and closes a gas pipe through which gas flows, can effectively suppress turbulence in the secondary pressure while maintaining good responsiveness of the opening and closing control of the solenoid valve that follows the secondary pressure.

[0010]

[0011] Furthermore, according to the above-described configuration, firstly, the amplitude, which is the difference between the maximum and minimum values ​​of the secondary pressure in a predetermined unit time after the switching point, is derived, and the point in time when this amplitude falls below a predetermined reference amplitude is set as the end of the opening / closing control suppression period. Therefore, the point in time when control failures will no longer occur when the secondary pressure is controlled by solenoid valve opening / closing control can be accurately predicted based on the derived damping ratio.

[0012]

[0013]

[0014] The solenoid valve control mechanism for achieving the above objective is: A solenoid valve control mechanism equipped with a control device that controls the open / closed state of a solenoid valve that opens and closes a gas flow pipe through which gas flows, the characteristic configuration of which is: The solenoid valve is equipped with a secondary pressure measuring unit for measuring the secondary pressure on the secondary side, The control device performs solenoid valve opening and closing control such that when the opening / closing control index, which is the secondary pressure measured by the secondary pressure measuring unit, exceeds a predetermined secondary pressure upper threshold, the solenoid valve is closed, and when it falls below a predetermined secondary pressure lower limit, the solenoid valve is opened. From the first switching point, which is the switching point for switching the solenoid valve from the closed state to the open state, or the second switching point, which is the switching point for switching the solenoid valve from the open state to the closed state, solenoid valve opening / closing suppression control is performed to suppress the opening and closing of the solenoid valve for a predetermined opening / closing control suppression period, using either the secondary pressure immediately before the switching point or the average value of the secondary pressure during the predetermined period immediately before the current time as the opening / closing control index. When the secondary pressure of the solenoid valve is the dependent variable and time is the independent variable, a sine function derivation process is performed to derive a sine function that approximates the secondary pressure with a sine curve at predetermined unit time intervals after the switching point, The key feature is the execution of an end-time setting control, which sets the point in time when the amplitude of the sine function derived in the sine function derivation process becomes less than a predetermined reference amplitude as the end of the opening / closing control suppression period. A solenoid valve control method for achieving the above objective is: A solenoid valve control method for controlling the open / closed state of a solenoid valve that opens and closes a gas flow pipe through which gas flows, the characteristic configuration thereof is: The solenoid valve opening and closing control is performed such that when the opening and closing control index, which is the secondary pressure measured on the secondary side of the solenoid valve, exceeds a predetermined secondary pressure upper threshold, the solenoid valve is closed, and when it falls below a predetermined secondary pressure lower limit, the solenoid valve is opened. After the first switching point as the switching point for switching the electromagnetic valve from the closed state to the open state or the second switching point as the switching point for switching the electromagnetic valve from the open state to the closed state, for a predetermined opening / closing control suppression period, the opening / closing control index is set to either the secondary pressure immediately before the switching point or the average value of the secondary pressure in a predetermined period immediately before the current time point, and electromagnetic valve opening / closing suppression control for suppressing the opening and closing of the electromagnetic valve is executed. When the secondary pressure of the electromagnetic valve is used as the explained variable and time is used as the explanatory variable, a sine function derivation process for deriving a sine function that approximates the secondary pressure as a sine curve every predetermined unit time after the switching point. There is a point of executing an end point setting control for setting the point at which the amplitude of the sine function derived in the sine function derivation process becomes less than a predetermined reference amplitude as the end point of the opening / closing control suppression period.

[0015] As described above, usually, when measuring the secondary pressure of an electromagnetic valve, as shown in FIG. 6, noise called spike noise Sn that greatly deviates from the value of the normal secondary pressure may occur. According to the above characteristic configuration, first, by the sine function derivation process, a sine function that approximates the secondary pressure as a sine curve every predetermined unit time after the switching point is derived. Therefore, the sine function is a function along the amplitude of the normal secondary pressure in a form that sufficiently reduces the influence of spike noise, which has a much smaller number of measurement points than the normal number of measurement points for measuring the secondary pressure. Thus, since the point at which the amplitude of the sine function derived in the sine function derivation process becomes less than a predetermined reference amplitude is set as the end point of the opening / closing control suppression period, the influence of spike noise can be reduced when deriving the end point of the opening / closing control suppression period.

Brief Description of the Drawings

[0016] [Figure 1] It is a schematic configuration diagram of an electromagnetic valve control mechanism according to an embodiment. [Figure 2] It is a graph showing the disturbance of the secondary pressure when the electromagnetic valve is shifted from the closed state to the open state. [Figure 3]This graph illustrates an example of a control failure that occurs when solenoid valve opening and closing control is performed based on a turbulent secondary pressure. [Figure 4] This is a control flow diagram of solenoid valve opening / closing control and solenoid valve opening / closing suppression control related to a reference configuration. [Figure 5] This graph illustrates solenoid valve opening / closing control and solenoid valve opening / closing suppression control in a reference configuration. [Figure 6] This is a graph illustrating the solenoid valve opening / closing control and solenoid valve opening / closing suppression control according to the embodiment. [Figure 7] This is a graph illustrating solenoid valve opening / closing control and solenoid valve opening / closing suppression control according to a different embodiment. [Modes for carrying out the invention]

[0017] The solenoid valve control mechanism 100 and solenoid valve control method according to an embodiment of the present invention are capable of maintaining good responsiveness of opening and closing control of a solenoid valve that follows the secondary pressure while effectively suppressing disturbances in the secondary pressure when feedback control of a solenoid valve that opens and closes a gas pipe through which gas flows, based on the pressure on the secondary side of the solenoid valve. The solenoid valve control mechanism 100 and the solenoid valve control method will be described below based on the drawings. Furthermore, although not included in the scope of the rights of this application, a reference embodiment of a solenoid valve control mechanism and solenoid valve control method will be described below before describing the solenoid valve control mechanism 100 and solenoid valve control method according to the embodiment.

[0018] [Reference form] The reference As shown in Figure 1, the solenoid valve control mechanism 100 comprises a solenoid valve V that opens and closes a gas flow pipe L through which gas (for example, city gas 13A) flows, a pressure sensor P (an example of a secondary pressure measuring unit) that measures the secondary pressure on the secondary side of the solenoid valve V, and a control device C that controls the open / closed state of the solenoid valve V based on the secondary pressure measured by the pressure sensor P.

[0019] More specifically, the control device C is realized through the cooperation of hardware and software, and executes a solenoid valve control method that includes solenoid valve opening and closing control, which closes the solenoid valve V when the opening / closing control index, as a secondary pressure measured by the pressure sensor P, exceeds a predetermined secondary pressure upper threshold (a value higher than the control target pressure (e.g., 2.3 kPa)), and opens the solenoid valve V when it falls below a predetermined secondary pressure lower limit (a value lower than the control target pressure (e.g., 2.3 kPa)), and solenoid valve opening and closing suppression control, which, after the first switching point, which is the switching point for switching the solenoid valve V from the closed state to the open state, or the second switching point, which is the switching point for switching from the open state to the closed state, suppresses the opening and closing of the solenoid valve V for a predetermined opening / closing control suppression period, using the opening / closing control index as the secondary pressure immediately before the switching point.

[0020] Here, we will add an explanation about the derivation process for the opening / closing control suppression period. As illustrated in Figure 5, the control device C, with the secondary pressure of the solenoid valve V as the dependent variable and time as the independent variable, controls the control device C after the aforementioned switching time ts for a predetermined unit time T(T1, T2, ...T k For example, extrapolate the maximum value Pα and minimum value Pβ of the secondary pressure at intervals of 0.1 seconds to 1.0 seconds. ru seki The number F1 is derived from the first 1st Seki Number derivation process and, 1st Seki The number was derived through a numerical derivation process. Taseki The system performs an end-time setting control, which sets the point at which the amplitude ΔP of F1 falls below a predetermined reference amplitude ΔPi (for example, 0.02 kPa if the control target pressure is 2.3 kPa) as the end-time te of the switching control suppression period. In other words, the control device C suppresses the opening and closing control of the solenoid valve V based on the disturbed secondary pressure from the start time ts of the opening and closing control suppression period until the end time te of the opening and closing control suppression period, when it is considered that the disturbance in the secondary pressure caused by the solenoid valve V changing from a closed state to an open state at the start time ts of the opening and closing control suppression period has sufficiently attenuated, thereby preventing malfunction of the secondary pressure control. Incidentally, in the example shown in Figure 5, during the opening / closing suppression period, the control device C does not control the opening or closing of the solenoid valve V, and maintains the current open / closed state, regardless of whether the pressure sensor P exceeds the secondary pressure upper limit threshold or falls below the secondary pressure lower limit threshold (as shown by γ in Figure 5).

[0021] The following provides further details on solenoid valve opening / closing control and solenoid valve opening / closing suppression control, based on the control flow diagram in Figure 4 and the graph in Figure 5. Control device C starts controlling the opening and closing of the solenoid valve and sets the secondary pressure measured by the pressure sensor P as the opening and closing control index (#01, #02). In the solenoid valve opening and closing control, if the opening and closing control index, which is the secondary pressure measured by the pressure sensor P, exceeds the secondary pressure upper threshold (YES in #03), the control device C switches the solenoid valve V to the closed state (#04), and if it falls below the secondary pressure lower limit, Match (YES in #03) solenoid valve Open V Switch to release state (#04) If the opening / closing control index, which is the secondary pressure measured by the pressure sensor P, is below the upper limit threshold of the secondary pressure and above the lower limit threshold of the secondary pressure (NO in #03), the current open / closed state of the solenoid valve V is maintained. When the solenoid valve V is switched open or closed in #04, control device C starts solenoid valve opening / closing suppression control at the time of the switch ts (#05), and sets the opening / closing control index to the secondary pressure (fixed value) immediately before the switching of the solenoid valve V's open / closing state is performed (#06). As a result, the opening / closing control index is fixed while the solenoid valve opening / closing suppression control continues, and the current open / closed state of the solenoid valve V is maintained. Furthermore, the control device C controls the maximum value Pα of the secondary pressure measured by the pressure sensor P at each unit time T. and minimum value Pβ Extract (#07), and based on the maximum and minimum values ​​of the extracted secondary pressure, 1st Seki The number derivation process is executed (#08). 1st Seki In the numerical derivation process, the maximum value of the secondary pressure derived for each unit time T is obtained. and minimum value By extrapolation approximation Riseki Derive the number F1. This will give the maximum value of the secondary pressure per unit time T at a point in time later than the secondary pressure data set obtained at the present time. and minimum value PβThis is predicted. Regarding By using an approximation with the number F1, the influence of spike noise Sn on control can be sufficiently reduced. As shown in Figure 5, the control device C is the 1st Seki The number was derived through a numerical derivation process. Taseki The point at which the amplitude ΔP of F1 becomes less than a predetermined reference amplitude ΔPi is set as the termination point te of the solenoid valve opening / closing suppression control (#09). When the set termination point is reached, the solenoid valve opening / closing suppression control ends and the system returns to solenoid valve opening / closing control (#10). Here, if there is no command to terminate the solenoid valve opening / closing control, i.e., the control device C will not terminate the solenoid valve opening / closing control from an external source. of If no termination control signal is input (in #11) No ), repeat the control from #02 to #10, and if there is a command to terminate the solenoid valve opening and closing control (at #11) Yes ), terminate control.

[0022] the above reference In this configuration, the control device C, in solenoid valve opening / closing suppression control, is shown to use the secondary pressure immediately before the switching point as the opening / closing control index for a predetermined opening / closing control period from the switching point. As another example of control, in solenoid valve opening / closing suppression control, the control device C can use the average value (here, a moving average) of the secondary pressure during the predetermined period immediately preceding the current time (for example, a time of 0.1 seconds or more and 1.0 seconds or less) as the opening / closing control index from the time of switching to a predetermined opening / closing control period.

[0023]

[0024] [Embodiment] In the solenoid valve control mechanism 100 and solenoid valve control method according to this embodiment, Control device C is , place For each fixed unit time T (for example, a time between 0.1 seconds and 1.0 seconds), the secondary pressure is approximated by a sinusoidal curve. do . More specifically, as shown in Figure 6, the control device C, with the secondary pressure of the solenoid valve V as the dependent variable and time as the independent variable, controls the control device C after the switching time ts by a predetermined unit time T(T1, T2, ...T kFor example, the system is configured to perform a sine function derivation process that derives a sine function F2 obtained by approximating the secondary pressure with a sine curve at intervals of 0.1 seconds to 1.0 seconds, and an end-time setting control that sets the point at which the amplitude ΔP of the sine function F2 derived in the sine function derivation process becomes a predetermined reference amplitude ΔPi (for example, 0.02 kPa when the control target pressure is 2.3 kPa) as the end-time te of the switching control suppression period. do . That is, in the solenoid valve control mechanism 100 and solenoid valve control method according to this embodiment, the control device C replaces the "first function derivation process" in the above [reference embodiment] with the "sine function derivation process".

[0025] [Another embodiment] ( 1 As shown in Figure 7, the control device C operates at predetermined unit times T(T1, T2, ...T k For example, the system may be configured to perform an end-time setting control, which derives the amplitude ΔP, which is the difference between the maximum value Pα and the minimum value Pβ of the secondary pressure during a period of 0.1 seconds or more and 1.0 seconds or less, and sets the point in time when this amplitude ΔP becomes less than a predetermined reference amplitude ΔPi (for example, 0.02 kPa when the control target pressure is 2.3 kPa) to be the end time te of the switching control suppression period. That is, in the solenoid valve control mechanism 100 and solenoid valve control method according to the said alternative embodiment, the control device C derives "the amplitude ΔP of the function F1 derived in the first function derivation process" in the above [Reference Embodiment] as "deriving the amplitude ΔP".

[0026] ( 2 In the above embodiment, city gas 13A was used as an example of the gas to be controlled, but the control can be performed effectively even when other gases are targeted, not just this gas.

[0027] Furthermore, the above Reference form and The configurations disclosed in the embodiments (including other embodiments, the same applies hereinafter) can be applied in combination with configurations disclosed in other embodiments, provided that this does not lead to a contradiction. Furthermore, the embodiments disclosed herein are illustrative, and the embodiments of the present invention are not limited thereto and can be modified as appropriate without departing from the object of the present invention. [Industrial applicability]

[0028] The solenoid valve control mechanism and solenoid valve control method of the present invention can be effectively used as a solenoid valve control mechanism and solenoid valve control method that can maintain good responsiveness of opening and closing control of the solenoid valve that follows the secondary pressure while effectively suppressing disturbances in the secondary pressure when feedback control of a solenoid valve that opens and closes a gas pipe through which gas flows based on the pressure on the secondary side of the solenoid valve. [Explanation of Symbols]

[0029] 100: Solenoid valve control mechanism C: Control device F1 : Seki number F2: sine Seki number L : Gas flow piping P: Pressure sensor Pα: Maximum value Pβ: Minimum value T: Unit time V: Solenoid valve te: End point ts: Switching point ΔP: amplitude

Claims

1. A solenoid valve control mechanism comprising a control device for controlling the open / closed state of a solenoid valve that opens and closes a gas flow pipe through which gas flows, The solenoid valve is equipped with a secondary pressure measuring unit for measuring the secondary pressure on the secondary side, The control device performs solenoid valve opening and closing control such that when the opening / closing control index, which is the secondary pressure measured by the secondary pressure measuring unit, exceeds a predetermined secondary pressure upper threshold, the solenoid valve is closed, and when it falls below a predetermined secondary pressure lower limit, the solenoid valve is opened. From the first switching point, which is the switching point for switching the solenoid valve from the closed state to the open state, or the second switching point, which is the switching point for switching the solenoid valve from the open state to the closed state, solenoid valve opening / closing suppression control is performed to suppress the opening and closing of the solenoid valve for a predetermined opening / closing control suppression period, using either the secondary pressure immediately before the switching point or the average value of the secondary pressure during the predetermined period immediately before the current time as the opening / closing control index. A solenoid valve control mechanism that, after the switching point, derives an amplitude which is the difference between the maximum and minimum values ​​of the secondary pressure in a predetermined unit time, and performs an end-time setting control which sets the point in time when the amplitude becomes less than a predetermined reference amplitude as the end of the opening / closing control suppression period.

2. A solenoid valve control mechanism comprising a control device for controlling the open / closed state of a solenoid valve that opens and closes a gas flow pipe through which gas flows, The solenoid valve is equipped with a secondary pressure measuring unit for measuring the secondary pressure on the secondary side, The control device performs solenoid valve opening and closing control such that when the opening / closing control index, which is the secondary pressure measured by the secondary pressure measuring unit, exceeds a predetermined secondary pressure upper threshold, the solenoid valve is closed, and when it falls below a predetermined secondary pressure lower limit, the solenoid valve is opened. From the first switching point, which is the switching point for switching the solenoid valve from the closed state to the open state, or the second switching point, which is the switching point for switching the solenoid valve from the open state to the closed state, solenoid valve opening / closing suppression control is performed to suppress the opening and closing of the solenoid valve for a predetermined opening / closing control suppression period, using either the secondary pressure immediately before the switching point or the average value of the secondary pressure during the predetermined period immediately before the current time as the opening / closing control index. When the secondary pressure of the solenoid valve is the dependent variable and time is the independent variable, a sine function derivation process is performed to derive a sine function that approximates the secondary pressure with a sine curve at predetermined unit time intervals after the switching point, A solenoid valve control mechanism that performs termination point setting control, which sets the point in time when the amplitude of the sine function derived in the sine function derivation process becomes less than a predetermined reference amplitude as the end of the opening / closing control suppression period.

3. A solenoid valve control method for controlling the open / closed state of a solenoid valve that opens and closes a gas flow pipe through which gas flows, The solenoid valve opening and closing control is performed such that when the opening and closing control index, which is the secondary pressure measured on the secondary side of the solenoid valve, exceeds a predetermined secondary pressure upper threshold, the solenoid valve is closed, and when it falls below a predetermined secondary pressure lower limit, the solenoid valve is opened. From the first switching point, which is the switching point for switching the solenoid valve from the closed state to the open state, or the second switching point, which is the switching point for switching the solenoid valve from the open state to the closed state, solenoid valve opening / closing suppression control is performed to suppress the opening and closing of the solenoid valve for a predetermined opening / closing control suppression period, using either the secondary pressure immediately before the switching point or the average value of the secondary pressure during the predetermined period immediately before the current time as the opening / closing control index. A solenoid valve control method that, after the switching point, derives an amplitude which is the difference between the maximum and minimum values ​​of the secondary pressure in a predetermined unit time, and performs an end-time setting control which sets the point in time when the amplitude becomes less than a predetermined reference amplitude as the end of the opening / closing control suppression period.

4. A solenoid valve control method for controlling the open / closed state of a solenoid valve that opens and closes a gas flow pipe through which gas flows, The solenoid valve opening and closing control is performed such that when the opening and closing control index, which is the secondary pressure measured on the secondary side of the solenoid valve, exceeds a predetermined secondary pressure upper threshold, the solenoid valve is closed, and when it falls below a predetermined secondary pressure lower limit, the solenoid valve is opened. From the first switching point, which is the switching point for switching the solenoid valve from the closed state to the open state, or the second switching point, which is the switching point for switching the solenoid valve from the open state to the closed state, solenoid valve opening / closing suppression control is performed to suppress the opening and closing of the solenoid valve for a predetermined opening / closing control suppression period, using either the secondary pressure immediately before the switching point or the average value of the secondary pressure during the predetermined period immediately before the current time as the opening / closing control index. When the secondary pressure of the solenoid valve is the dependent variable and time is the independent variable, a sine function derivation process is performed to derive a sine function that approximates the secondary pressure with a sine curve at predetermined unit time intervals after the switching point, A solenoid valve control method that performs an end-time setting control, which sets the point in time when the amplitude of the sine function derived in the sine function derivation process becomes less than a predetermined reference amplitude as the end of the opening / closing control suppression period.

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