JP6668411B2 - Control unit of control valve, control valve device, air conditioning system, and control valve control method - Google Patents

Description

  The present invention relates to a control unit, a control method, and a control valve device for a control valve.

  Since the opening-air flow (flow rate) characteristic of the control valve that adjusts the flow rate according to the opening degree of the valve is not a straight line, the responsiveness varies depending on the magnitude of the opening degree. That is, the amount of change in the air volume (flow rate) for the same operation amount differs depending on the magnitude of the opening. The air volume (flow rate) is also affected by the differential pressure across the control valve. Such characteristics differ depending on the type and size of the valve, and also differ among manufacturers of the same type of valve.

  In order to avoid such control complexity, when controlling the flow rate of fluid with a control valve, measure the current flow rate and determine the manipulated variable according to the magnitude of the deviation between the target flow rate and the current flow rate. Feedback control has been performed.

JP-A-9-287798 JP 2010-169306 A JP-A-5-204466 JP 2010-223540 A

  However, in this feedback control, since the responsiveness changes depending on the magnitude of the opening, hunting occurs when the opening is small, and a slow operation occurs when the opening is large. . For this reason, there is a problem that it is necessary to substantially set upper and lower limits in the control range.

  In order to alleviate such restrictions on the control range, various measures have been taken such as devising the flow path shape of the control valve to make the opening-air flow rate (flow rate) characteristic close to a straight line. ) It is difficult to design the characteristics to be sufficiently close to a straight line, and the shape of the flow path becomes complicated.

  Therefore, an object of the present invention is to provide a technique for controlling a control valve that can quickly achieve desired control regardless of the characteristics and instrumental differences of the control valve.

In order to solve the above problems, the control valve device of the present invention,
Having a control valve and a control unit of the control valve,
The control unit comprises:
Opening degree of the control valve for controlling the flow rate of the fluid by opening and closing the valve,
An opening command value that is a value used for performing the control and that can be used to control the valve opening of the control valve by receiving the flow rate of the fluid passing through the control valve or the flow rate of the fluid or another device. A control base value that is
A differential pressure of the fluid passing through the control valve before and after the valve,
A storage unit storing characteristic data indicating the relationship of
A differential pressure recognition unit that recognizes by detecting or calculating the differential pressure before and after the valve,
The differential pressure recognized by the differential pressure recognition unit and the control basic value required for controlling the control valve are acquired from the storage unit or another device, and the control corresponding to the acquired differential pressure and the control basic value required for the control is performed. A processing unit that obtains an opening degree of the valve based on the characteristic data, and outputs an opening degree signal based on the opening degree;
A drive unit that opens and closes the valve so as to have an opening based on the opening signal,
The control valve is:
A channel for the fluid,
The valve for controlling the flow rate of the fluid by opening and closing,
Transmission means for transmitting the differential pressure before and after the valve to the differential pressure recognition unit,
With.

  In the control valve device, the control base value is a flow rate of the fluid or the flow rate of the fluid passing through the control valve, and the control base value required for the control is a required flow rate or a required flow rate to pass through the control valve. The characteristic data may be data indicating the valve opening degree as a function of a flow rate or a flow rate and a differential pressure across the valve.

  In the control valve device, the control base value is a flow rate of the fluid or the flow rate of the fluid passing through the control valve, and the control base value required for the control is a required flow rate or a required flow rate to pass through the control valve. The characteristic data is set for each flow rate or flow rate of the fluid passing through the control valve, and when the flow rate or flow rate changes, the processing unit corresponds to the opening degree of the control valve corresponding to the flow rate or flow rate. It may be determined based on characteristic data to be obtained.

In the control valve device, the characteristic data is set for each of the differential pressures,
The processing unit may determine the opening degree of the control valve based on characteristic data corresponding to the differential pressure.

In order to solve the above problems, the control method of the control valve of the present invention,
Opening of a control valve that controls the flow rate of fluid by opening and closing the valve,
An opening command value that is a value used for performing the control and that can be used to control the valve opening of the control valve by receiving the flow rate of the fluid passing through the control valve or the flow rate of the fluid or another device. A control base value that is
A differential pressure of the fluid passing through the control valve before and after the valve,
Reading the characteristic data from a storage unit storing characteristic data indicating the relationship of
A step of recognizing the differential pressure by detecting or calculating the differential pressure before and after the valve,
A processing unit acquires the differential pressure recognized by the differential pressure recognition unit and a control basic value required for control of the control valve from the storage unit or another device, and acquires the acquired differential pressure and a control basic value required for the control. Obtaining the opening of the control valve corresponding to the characteristic data, and outputting an opening signal based on the opening,
Execute

  In the control method, the control base value is a flow rate of the fluid or a flow rate of the fluid passing through the control valve, and the control base value required for the control is a required flow rate or a required flow rate to pass through the control valve. The characteristic data may be data indicating the valve opening degree as a function of a flow rate or a flow rate and a differential pressure across the valve.

  In the control method, the control base value is a flow rate of the fluid or a flow rate of the fluid passing through the control valve, and the control base value required for the control is a required flow rate or a required flow rate to pass through the control valve. The characteristic data is set for each flow rate or flow rate of the fluid passing through the control valve, and when the flow rate or flow rate changes, the processing unit corresponds to the opening degree of the control valve corresponding to the flow rate or flow rate. It may be characteristic data.

  ADVANTAGE OF THE INVENTION According to this invention, the technique of controlling the control valve which can achieve desired control quickly can be provided irrespective of the characteristic of a control valve, and an instrumental difference.

FIG. 1 is a schematic configuration diagram of the control valve device according to the first embodiment. FIG. 2 is a diagram of characteristic data representing the opening degree of the valve body with respect to the values related to the air volume Q and ΔP. FIG. 3 is a diagram illustrating an example of the characteristic curve. FIG. 4 is an explanatory diagram of a control method of the control valve. FIG. 5 is an explanatory diagram of a specific operation in controlling the control valve when the required flow rate increases. FIG. 6 is an explanatory diagram of a specific operation in controlling the control valve when the required flow rate increases. FIG. 7 is an explanatory diagram of a specific operation in controlling the control valve when the differential pressure increases. FIG. 8 is an explanatory diagram of a specific operation in controlling the control valve when the differential pressure increases. FIG. 9 is a diagram illustrating an example of the characteristic data of the first modification. FIG. 10 is a diagram illustrating an example in which the opening degree of the valve body is obtained using the characteristic data of the first modification. FIG. 11 is a diagram illustrating an example of the characteristic data of the second modification. FIG. 12 is a diagram illustrating an example in which the opening degree of the valve body is obtained using the characteristic data of the second modification. FIG. 13 is a schematic diagram illustrating an air conditioning system according to the second embodiment. FIG. 14 is a diagram illustrating an example of the correction curve. FIG. 15 is an explanatory diagram of the control method of the control valve according to the second embodiment.

<First embodiment>
"Device configuration"
FIG. 1 is a schematic configuration diagram of a control valve device 10 according to the present embodiment. As shown in FIG. 1, a control valve device 10 has a control valve 1 and a control unit 2, is connected to a duct or the like of an air conditioning system, and the control unit 2 controls opening and closing of the control valve 1 to control the control valve 1. The flow rate (air volume) of the air passing through the inside 1 is controlled.

  The control valve 1 includes a main body 11, a valve element (throttle mechanism) 12, and a differential pressure tube (transmission means) 13.

  The main body 11 is a tubular member (tubular body) having an inner air passage as an air flow path, and is connected to, for example, an air supply duct in a VAV type air conditioning system.

  The valve body 12 is opened and closed under the control of the control unit 2, and maximizes the opening area inside the main body 11 in the open state and minimizes the opening area inside the main body 11 in the closed state. (Including stopping). The valve body 12 may be of any type as long as the air volume can be controlled by opening and closing. In this embodiment, the valve body 12 is a butterfly valve having a rotating shaft 121 and a diaphragm blade 122. The diaphragm blade 122 is a plate-like member having an outer shape substantially the same as the shape of the inner space of the main body on a plane orthogonal to the flow direction 19 of the air passing through the main body 11, and is rotatable about the rotary shaft 121. Is held.

  The differential pressure tube 13 is a transmission unit that transmits the differential pressure across the valve body 12 to the control unit 2. Here, the front and rear of the valve body 12 mean that the upstream side is the front side and the downstream side is the rear side in the air flow direction 19 with respect to the valve body 12.

  One end of the differential pressure tube 13 is connected to the main body 11 at the front side of the valve body 12 and communicates with the air flow path, and the other end is connected to the front side tube (front side transmission means) 131 connected to the control unit 2. A rear tube (rear transmission means) 132 is connected to the main body 11 at the rear side of the valve body 12 and communicates with the air flow path, and the other end is connected to the control unit 2.

  Further, the control unit 2 includes a storage unit 21, a differential pressure recognition unit 22, a processing unit 23, and a driving unit 24.

  The storage unit 21 stores data such as a ROM (Read Only Memory), a RAM (Random Access Memory), a PROM (Programmable Read-Only Memory), an EEPROM (Electrically Erasable Programmable Read-Only Memory), and is electrically readable. Storage device. The storage unit 21 stores characteristic data indicating a relationship between an opening degree of the control valve 1, a required flow rate (control basic value) for performing control, and a differential pressure of air passing through the control valve 1 before and after the valve. ing. This characteristic data differs for each commercially available control valve, and is obtained by performing a test (actual measurement) on each of them in advance, and is stored in the storage unit 21. The characteristic data is not limited to the actually measured data, but includes data obtained by correcting the actually measured data, data converted from characteristic data of similar control valves, data estimated from control valve specifications, data calculated by simulation, and the like. There may be.

  The differential pressure recognition unit 22 recognizes by detecting or calculating the differential pressure before and after the valve. The differential pressure recognition unit 22 of the present embodiment is a differential pressure gauge that measures a pressure difference between two points, and one of the input ports (bases) 221 is connected to the front tube 131 and the other is connected to the rear tube 132. Have been. The differential pressure recognition unit 22 displaces a pressure receiving element (for example, a diaphragm) by a difference in pressure transmitted to two input ports, and determines the amount of displacement by a change in resistance of a semiconductor strain gauge, a change in capacitance between electrodes, or the like. The configuration is such that the signal is converted into an electric signal and output as a differential pressure signal. The method of measuring the differential pressure before and after the valve is not limited to this, and pressure sensors for measuring the absolute value of the pressure are installed before (upstream) and after (downstream) the valve, respectively. May be connected to a differential pressure recognition unit via a communication line, and the differential pressure recognition unit may calculate the difference from the numerical values detected by the two pressure sensors. In this case, the communication line constitutes the transmission means of the present application.

  The processing unit 23 obtains an opening degree of the control valve 1 corresponding to the differential pressure and the required flow rate recognized by the differential pressure recognition unit 22 based on the characteristic data, and outputs an opening degree signal based on the opening degree. A device that performs the above processing, for example, a general-purpose processor (CPU, MPU, etc.) that performs the above processing based on a program, an application specific integrated circuit (ASIC) that performs the above processing, and a logic circuit that performs the above processing can be set. Such as a programmable logic device.

  The drive unit 24 has a drive source 241 such as a stepping motor and a power transmission mechanism 242 that transmits the driving force of the drive source 241 to the rotation shaft 121 of the valve body 12. Further, the drive unit 24 may include a sensor (for example, an encoder) for detecting an opening degree of the valve body 12 such as an angle, a position, and a movement amount of the valve body 12.

<< Description of characteristic data >>
When the flow rate (air volume) of the air passing through the control valve 1 is adjusted by opening and closing the valve body 12, for example, if the valve body 12 is closed, that is, if the resistance of the valve body 12 is high, the dynamic pressure is increased. As a result, the pressure increases on the front side of the valve body 12, and the pressure difference between the front and rear of the valve body 12 increases. On the other hand, when the valve element 12 is open, that is, when the resistance of the valve element 12 is low, the pressure increase at the front side of the valve element 12 due to the dynamic pressure is small, and the pressure difference between the front and rear of the valve element 12 is small.

The relationship between the air volume Q, the differential pressure ΔP, and the resistance coefficient ξ is generally represented by the following equation. Here, A is the cross-sectional area of the flow path in which the valve body is installed, and ρ is the density of the fluid.

抵抗係数ξが弁体１２の開度（本例では角度θ）毎に一意に定まる場合、右辺の値に
対応するθは一意に定まる。即ち、右辺の値とθとの関係は、１本の曲線（以下、特性曲線とも称す）で表されることになる。 In Expression 1, when the airflow Q and ΔP, which are input values, are put together on the left side, the right side becomes a function of only the resistance coefficient ξ as shown in Expression 2.

When the resistance coefficient ξ is uniquely determined for each opening degree of the valve body 12 (the angle θ in this example), θ corresponding to the value on the right side is uniquely determined. That is, the relationship between the value on the right side and θ is represented by a single curve (hereinafter also referred to as a characteristic curve).

  FIG. 2 is a characteristic curve showing the relationship between the value θ on the right side of Expression 2 and the angle θ, that is, characteristic data representing the opening degree of the valve body 12 with respect to the values relating to the airflow Q and ΔP (the value on the left side of Expression 2). It is.

  In FIG. 2, this correspondence is shown by a characteristic curve 31 with the value on the left side of Equation 2 taken on the vertical axis and the angle θ of the valve element 12 taken on the horizontal axis. This characteristic curve 31 shows, for each angle θ of the valve element 12 of the control valve 1, the relationship between the air volume Q passing through the control valve 1 and the value related to the differential pressure ΔP before and after the valve element 12, for example, the equipment to be constructed. Are measured in advance in the test facility, and stored in the storage unit as characteristic data such as a correspondence table or a relational expression indicating the correspondence.

  Accordingly, when the target air volume, that is, the air volume required by the control (hereinafter, also referred to as a required air volume) Q and the differential pressure ΔP are input, the processing unit of the control unit 2, as shown in FIG. The value on the left side is determined, and the value 33 of the angle θ with respect to this value 32 is determined based on the characteristic curve 31.

  Here, the angle θ is, for example, 0 ° when the valve body 12 is in a fully closed state, and from the fully closed state to a position of the valve body 12 when the valve body 12 is rotated about an axis of rotation 121 in an opening direction. Is the rotation angle. The opening degree of the valve element 12 is not limited to the angle θ, and may be, for example, 0% in a fully closed state and 100% in a fully open state, and may be indicated as a value from 0% to 100%.

Further, in the example of FIG. 2, as the characteristic data, the correspondence between the value on the left side of Expression 2 and the angle θ is obtained. However, the expression for obtaining the correspondence between the opening (angle θ) of the valve element 12 is as follows. Not limited to this, any equation may be used as long as the equation 1 is separated into variables so that the “resistance coefficient” and the “air volume Q and the differential pressure ΔP” are different sides. For example, Equation 1 may be transformed into Equation 3, and the value on the left side of Equation 3 may be used as a value for determining the correspondence relationship with the opening of the valve body 12. The correspondence between the value on the left side of Equation 3 (resistance coefficient 式) and the opening degree (angle θ) of the valve element 12 may be obtained as characteristic data. If the value taken on the vertical axis is Q / √ΔP (the left side of Equation 2) or its reciprocal, the calculation is simplified, the number of digits of the numerical value is reduced, and the processing speed of the processing unit 23 is improved. Is more preferable.

  Further, when high-precision controllability is required, the influence of the difference in the resistance coefficient when the air volume Q (or the wind speed V) differs may not be negligible. In such a case, the control may be performed using a plurality of characteristic curves for each air volume Q (or wind speed V).

  FIG. 3 shows a case where the characteristic curves 34 to 38 are obtained every 1 m / s from a wind speed of 3 m / s to a wind speed of 7 m / s. As a result, the opening degree (angle θ) of the valve element 12 can be obtained with high accuracy using the characteristic curves 34 to 38 corresponding to the air volume Q (or the wind speed V).

  For example, when the set wind speed is 4.1 m / s and the value of the function of the input value is Ia, the value θ35 of the characteristic curve 35 and the value θ36 of the characteristic curve 36 corresponding to Ia are obtained as shown in FIG. Then, a value θa corresponding to the wind speed of 4.1 m / s during this period is determined.

《Control method》
FIG. 4 is an explanatory diagram of a control method of the control valve 1. When the power is turned on, the control unit 2 operates the differential pressure recognition unit 22 and the processing unit 23 to execute the processing (control method) in FIG.

  First, the differential pressure recognition unit 22 detects a difference between the pressure on the front side of the valve body 12 transmitted via the front tube 131 and the pressure on the rear side of the valve body 12 transmitted via the rear tube 132, An electric signal corresponding to the differential pressure is input to the processing unit 23 (Step S1). The detection of the differential pressure may be performed at a predetermined sampling cycle or may be performed when requested by the processing unit 23 or the like.

  The processing unit 23 starts processing based on a preset program or logic (step S2), and acquires a required air volume (set air volume) Q (step S3). The acquisition of the required air volume Q may be performed by reading a value preset in the storage unit 21 or by receiving an input from another device such as an air conditioning system.

  The processing unit 23 that has received the differential pressure signal and obtained the required air volume obtains the value of the function relating to the differential pressure signal and the required air volume as shown in Expressions 2 and 3 (Step S4), and stores the characteristic data in the storage unit 21. (Step S5), the opening of the valve body 12 (for example, the angle θ) corresponding to the value of the function relating to the differential pressure signal and the required air volume is obtained based on the characteristic data, and transmitted to the drive unit 24 as the opening signal. (Step S6).

The driving unit 24 drives a driving source 241 such as a stepping motor based on the opening signal from the processing unit 23, and transmits the driving force of the driving source 241 to the rotation shaft 121 of the valve body 12 via the power transmission mechanism 242. By transmitting the rotation, the valve body 12 is rotated to adjust the opening degree indicated by the opening degree signal (step S7).
Here, the control base value may be the required flow velocity, and the flow velocity is replaced with the flow velocity by the equation of “flow rate = flow path cross sectional area × flow velocity” between the acquired required flow velocity and the previously acquired flow path cross sectional area. Can be used for control.
When the required flow velocity at the location where the aperture ratio of the flow channel is changed by control is used as the control base value, the input aperture ratio is obtained from the equation of “flow rate = cross-sectional area of flow channel × aperture ratio × flow velocity”. Then, the flow path cross-sectional area acquired in advance and the acquired required flow velocity may be replaced with a flow rate and used for control.

  5 and 6 are explanatory diagrams of specific operations in controlling the control valve 1 when the required air volume (flow rate) increases.

When the required airflow Q1 is flowing from the required airflow Q1 to the differential pressure ΔP1 before and after the valve element 12 and the opening degree θ1 of the valve element 12 (T1), the required airflow increases from Q1 to Q2 ( T2), the processing unit 23 obtains an angle θ2 corresponding to Q2 / √ΔP1 based on the characteristic curve (characteristic data) 51, and sends an opening signal to the driving unit 24 so that the angle of the valve body 12 is set to θ2. (T3).
The drive unit 24 rotates the valve element 12 according to the opening signal, and sets the angle of the valve element 12 to θ2 (T4).

  However, when the angle of the valve body 12 is changed from θ1 to θ2, the valve body 12 moves in the opening direction, so that the differential pressure across the valve body 12 decreases from ΔP1 to, for example, ΔP2 (T5), and the opening degree becomes θ2. Even if it reaches, the air volume does not reach Q2 (Q2 ').

Therefore, when the angle of the valve body 12 reaches θ2 and the differential pressure becomes ΔP2, the processing unit 23 calculates an angle θ3 corresponding to Q2 / √ΔP2, and opens the valve body 12 so that the angle of the valve body 12 is set to θ3. The degree signal is sent to the drive unit 24 (T6).
The drive unit 24 rotates the valve body 12 according to the opening signal, and sets the angle of the valve body 12 to θ3 (T7).

  However, when the angle of the valve body 12 is changed from θ2 to θ3, the valve body 12 moves in the opening direction, so that the differential pressure across the valve body 12 drops below ΔP2 (T8), and the opening reaches θ3. Also the air volume does not reach Q2.

  Thus, the process of obtaining the angle θ and controlling the angle of the valve body 12 is repeated as described above, and when the air volume finally reaches the required air volume Q2, the differential pressure is ΔP3 lower than ΔP2, and the opening is larger than θ2. It converges at θ4 (T9).

  For example, when the valve element 12 is rotated by the stepping motor (drive source 241), the rotation amount gradually decreases as the air volume approaches the required air volume Q2, and the difference between the angle based on the opening signal and the current angle becomes smaller. , And converges to a value equal to or less than the minimum drive amount of the drive unit 24 (for example, 0.18 °).

  As shown in FIG. 5, the control valve device 10 determines the angle (opening) of the valve element corresponding to the current differential pressure based on the characteristic data, and controls the valve element 12 to promptly request the air volume. The same air volume can be obtained.

  For example, in the case of the conventional feedback control, an operation of approaching the required air volume is performed by detecting the current air volume, calculating an air volume deviation from the required air volume, and performing a correction operation of a magnitude proportional to the air volume deviation. . At this time, if the proportionality constant at the time of calculating the correction amount is excessive, an operation (hunting) that alternates with the required air volume occurs. Conversely, since the proportional constant of the feedback control needs to be smaller as the opening of the valve body is smaller, it is necessary to make the operation slower by reducing the proportional constant when trying to use the flow control to a smaller opening. .

On the other hand, in the control valve device of the present embodiment, as described above, when the opening degree changes in the opening direction of the valve, the differential pressure decreases. When the opening degree changes in the direction, the differential pressure increases, so that the amount of air required in one operation slightly exceeds the required air volume. As described above, since the operation by the control valve device of the present application does not pass the required air volume, an operation (hunting) that alternates with the required air volume does not occur. In addition, since such characteristics of the present invention do not depend on the operation speed of the valve body, a stable operation without hunting can be ensured even if the operation speed is set as fast as the limit of the motor performance.

  In the description of FIGS. 5 and 6, in the processes T3, T5, and T9 of FIG. 5, the valve of the valve body corresponding to the differential pressure and the air flow (Q / √ΔP) is obtained from the characteristic curve (characteristic data) 51 shown in FIG. Although the opening degree θ is obtained, the present invention is not limited to this. As shown in FIG. 3, the valve element according to the differential pressure and the control basic value (Q / √ΔP) based on a plurality of characteristic curves for each of the air volume Q or the wind velocity V. May be approximated from a plurality of characteristic curves.

For example, if the required air volume increases to Q2 when the required air volume Q1 flows and the differential pressure is ΔP1, the value of Q2 / √ΔP1 is Ia in FIG. 3, the wind speed is Va, and a plurality of characteristic curves 34 to 38, the opening θ corresponding to the value Ia is obtained from the characteristic curve before and after the wind speed Va, and the opening θ corresponding to the wind speed Va is approximated from each opening θ. That is, if the wind speed Va is 4.1 m / s, the opening degrees θ35 and θ36 corresponding to the value Ia are obtained from the characteristic curve 35 of the wind speed V = 4 m / s and the characteristic curve 36 of the wind speed V = 5 m / s, respectively. The opening degree θa corresponding to the wind speed Va is approximated from the opening degrees θ35 and θ36 of FIG.

  FIGS. 7 and 8 are explanatory diagrams of specific operations in controlling the control valve 1 when the differential pressure increases.

When the required air volume Qa is flowing with the required pressure difference ΔPd before and after the valve element 12 and the opening degree θd of the valve element 12 with respect to the required flow rate Qa (T11), the differential pressure increases from ΔPd to ΔPc ( T12), the processing unit 23 obtains an angle θc corresponding to Qa / √ΔPc based on the characteristic curve (characteristic data) 52, and sends an opening signal to the driving unit 24 so that the angle of the valve body 12 is set to θc. (T13).
The drive unit 24 rotates the valve body 12 according to the opening signal, and sets the angle of the valve body 12 to θc (T14).

  However, when the angle of the valve body 12 is changed from θd to θc, the valve body 12 moves in the closing direction, so that the differential pressure across the valve body 12 increases from ΔPc to, for example, ΔPb (T5), and the opening degree becomes θc. Even then, the air volume rises to Qb.

Therefore, when the angle of the valve body 12 reaches θc and the differential pressure becomes ΔPb, the processing unit 23 obtains an angle θb corresponding to Qa / √ΔPb, and opens the valve body 12 so that the angle of the valve body 12 becomes θb. A degree signal is sent to the drive unit 24 (T16).
The drive unit 24 rotates the valve element 12 according to the opening signal, and sets the angle of the valve element 12 to θb (T17).

  When the angle of the valve body 12 is changed from θc to θb, the valve body 12 moves in the closing direction again, so that the differential pressure across the valve body 12 increases more than ΔPb (T18), and the opening degree becomes θb. Also the air volume becomes higher than Qa.

Therefore, the process of obtaining the angle θ and controlling the angle of the valve body 12 is repeated as described above,
When the air volume finally reaches the required air volume Qa, for example, the differential pressure converges at ΔPa higher than ΔPc and the opening degree θa smaller than θc (T19).

  In the example shown in FIG. 7 as well, the control valve device 10 determines the angle (opening) of the valve element corresponding to the current differential pressure based on the characteristic data, thereby quickly as in the example of FIG. The air volume can be adjusted as required.

<< Effect of Embodiment 1 >>
As described above, according to the present embodiment, the opening degree of the valve element 12 is uniquely determined from the required air volume and the differential pressure before and after the valve element 12, so that the control valve is configured to achieve the required air volume more quickly than in the feedback control. 1 can be controlled.

  Further, according to the present embodiment, high responsiveness is obtained in a wide range from fully closed to fully opened without being affected by the characteristics of the control valve 1, and control with high rangeability is not affected by the responsiveness. Becomes possible.

  The processing unit 23 receives the current value of the opening degree of the control valve 1 and the input of the differential pressure recognized by the differential pressure recognition unit 22, and obtains the current air volume (flow rate) based on the characteristic data. Is also good. By doing so, the current air volume (flow rate) can be confirmed, and it can be monitored whether the actual air volume is quickly controlled until the actual air volume becomes the required air volume after receiving the input of the required air volume. .

<< Modification 1 >>
In the first embodiment described above, the opening is obtained based on the characteristic data indicating the relationship between the differential pressure and the control base value and the opening corresponding thereto. However, the present invention is not limited to this configuration. The opening is determined based on the characteristic data indicating the relationship of the corresponding opening for each control basic value. Since other configurations are the same as those of the first embodiment, the same components are denoted by the same reference numerals and the description thereof will not be repeated.

  FIG. 9 is a diagram illustrating an example of the characteristic data according to the first modification. The characteristic data of FIG. 9 shows the differential pressure ΔP on the vertical axis, the opening θ of the valve body 12 on the horizontal axis, and shows the relationship between the differential pressure ΔP and the opening θ by a plurality of characteristic curves for each wind speed V. Was. This characteristic curve can be obtained by, for example, measuring in advance a valve or a valve used for the facility to be constructed at a test facility. The characteristic data of the first modification is not limited to the characteristic curve for each wind speed V, and may be a characteristic curve for each control basic value such as the airflow Q.

  The characteristic curve is obtained at a predetermined pitch from the minimum value to the maximum value of the required wind speed V and is stored in the storage unit 21. FIG. 9 shows a plurality of characteristic curves 54 to 59 from a wind speed of 1 m / s to a wind speed of 10 m / s. The pitch (interval) of the wind speed for obtaining each characteristic curve may be an equal interval or may be an irregular interval.

FIG. 10 is a diagram illustrating an example in which the opening degree of the valve body 12 is obtained using the characteristic data of the first modification. For example, when the set wind speed is 9.2 m / s and the differential pressure detected by the differential pressure recognition unit 22 is Pa,
First, two characteristic curves sandwiching the set wind speed of 9.2 m / s, that is, a characteristic curve whose wind speed V is lower than 9.2 m / s and a characteristic curve whose wind speed V is higher than 9.2 m / s are selected. In FIG. 10, a characteristic curve 55 closest to the set wind speed 9.2 m / s among the characteristic curves with the low wind speed V and a characteristic curve 55 closest to the set wind speed 9 with the high wind speed V
. A characteristic curve 54 close to 2 m / s is selected.

Next, the openings θ54 and θ55 at the positions where the differential pressure Pa input by the differential pressure recognition unit 22 and the characteristic curves 54 and 55 intersect are determined, and the opening θ55 at a wind speed of 9 m / s and θ54 at a wind speed of 10 m / s are calculated. Wind speed 9.2m / s
To obtain the opening degree θs.

  As described above, according to the first modification, since the opening degree θ of the valve element 12 is uniquely determined from the differential pressure ΔP before and after the valve element 12 and the required wind velocity V, the required wind velocity V is quickly achieved as compared with the feedback control. Control valve 1 can be controlled.

Further, in the first modification, the correspondence between the differential pressure ΔP and the opening degree θ of the valve body 12 is stored as characteristic data. Therefore, at the time of control, the detected differential pressure ΔP is used as it is, and the corresponding valve body is used. 12 can be obtained, and the processing at the time of control can be simplified.

  Further, in the first modification, since the characteristic data is set for each wind speed V or air volume Q, the relationship between the differential pressure ΔP and the opening degree θ of each characteristic curve is determined according to the respective air volume Q or wind speed V. The control valve 1 can be controlled with high accuracy by suppressing the influence of the difference in the relationship between the pressure difference ΔP and the opening θ when the air volume Q or the wind speed V is different.

<< Modification 2 >>
In the first embodiment described above, the opening is obtained based on the characteristic data indicating the relationship between the differential pressure and the control base value and the opening corresponding thereto. However, the present invention is not limited to this configuration. The opening degree of the valve body is determined based on the characteristic data indicating the relationship between and the corresponding opening degree for each differential pressure. Since other configurations are the same as those of the first embodiment, the same components are denoted by the same reference numerals and the description thereof will not be repeated.

  FIG. 11 is a diagram illustrating an example of the characteristic data according to the second modification. The characteristic data of FIG. 11 shows the wind speed V on the vertical axis, the opening θ of the valve body 12 on the horizontal axis, and shows the relationship between the wind speed V and the opening θ by a plurality of characteristic curves for each differential pressure ΔP. . This characteristic curve can be obtained by, for example, measuring in advance a valve or a valve used for the facility to be constructed at a test facility. It should be noted that the characteristic data of the second modification is not limited to the characteristic curve for the wind speed V, and the relationship between the control basic value such as the air flow Q and the opening degree θ of the valve body 12 is represented by a plurality of characteristic curves for each differential pressure ΔP. It may be something.

  This characteristic curve is determined at a predetermined pitch from the minimum value to the maximum value of the differential pressure ΔP and is stored in the storage unit 21. FIG. 11 shows a plurality of characteristic curves 71 to 76 from a differential pressure of 100 Pa to a differential pressure of 1000 Pa. The pitch (interval) of the differential pressure for obtaining each characteristic curve may be an equal interval or may be an irregular interval.

  FIG. 12 is a diagram illustrating an example in which the opening degree of the valve body 12 is obtained using the characteristic data of the second modification. For example, when the set wind speed is Va and the differential pressure detected by the differential pressure recognition unit 22 is 920 Pa, first, two characteristic curves sandwiching the differential pressure 920 Pa, that is, a characteristic curve having a differential pressure lower than the differential pressure 920 Pa and a differential pressure Select a characteristic curve with high In FIG. 11, a characteristic curve 75 closest to 920 Pa in the characteristic curve with a low differential pressure and a characteristic curve 76 closest to 920 Pa in a characteristic curve with a high differential pressure are selected.

  Next, the opening degrees θ75 and θ76 at the position where the set wind speed V intersects the characteristic curves 75 and 76 are obtained, and the opening degree θ75 of the differential pressure 900 Pa and the opening degree θ76 of the differential pressure 1000 Pa are proportionally divided by the differential pressure 920 Pa to obtain the opening degree Find θx.

  As described above, according to the first modification, since the opening degree θ of the valve element 12 is uniquely obtained from the required wind velocity V and the differential pressure ΔP before and after the valve element 12, the required wind velocity V is achieved more quickly than in the feedback control. Control valve 1 can be controlled.

  Further, in the first modification, the correspondence between the required wind speed V and the opening degree θ of the valve body 12 is stored as characteristic data. The opening degree θ can be obtained, and the processing at the time of control can be simplified.

<Embodiment 2>
Embodiment 2 shows an example in which the control valve device 10 is applied to an exhaust path of an air conditioning system 100. FIG. 13 is a schematic diagram illustrating an air conditioning system 100 according to the second embodiment.

As shown in FIG. 13, the air conditioning system 100 includes an air conditioner 4, a constant air volume control device 5, a room pressure gauge 6, a controller (control device) 7, and a control valve device 10, and controls air conditioning in the room 8. System. The room 8 is a room pressure control room in which the amount of air is controlled by controlling the opening and closing of the control valve 1 by controlling the opening and closing of the control valve 1 so that the room pressure is not disturbed by a disturbance when the door is opened and closed. (Also applicable to this use in the first embodiment).
The control valve device 10 has the same configuration as that of the first embodiment. For this reason, the same elements are denoted by the same reference numerals, and the description thereof will not be repeated.

  In the second embodiment, the operation when the required air volume of the control valve device 10 changes or when the differential pressure before and after the valve element 12 changes is the same as that in FIGS. 4 to 8 described above. In the second embodiment, the configuration in which the opening command value from the controller 7 is corrected based on the characteristic data and the opening of the valve body 12 is controlled so as to obtain the corrected opening is different from that of the first embodiment. Is different.

  The air conditioner 4 introduces outside air, adjusts the temperature, humidity, cleanliness, and the like to satisfy predetermined conditions, and supplies the air as air supply.

  The constant air volume control device 5 is disposed in an air supply path 61 through the air supply from the air conditioner 4, and sets the air supply supplied to the room 8 even if the static pressure in the air supply path 61 changes. This is a device that controls the air volume with a control valve (not shown) while measuring the passing wind speed with a wind speed sensor (not shown) so that the air volume becomes the adjusted air volume.

  The room pressure gauge 6 is a pressure gauge that measures the pressure in the room 8, and inputs the measured pressure to the controller 7 as an electric signal (room pressure signal).

  The controller 7 is a device that determines the opening of the control valve device 10 based on the room pressure measured by the room pressure gauge 6 and controls the opening of the control valve device 10 to adjust the pressure in the room 8.

  The control valve device 10 is a device that is disposed in the exhaust path 62 and controls the amount of exhaust air in accordance with an opening command value or the like from the controller 7. The control valve device 10 according to the second embodiment stores the characteristic data (correction curve) in the storage unit 21 for correcting the opening command value from the controller 7.

  FIG. 14 is a diagram illustrating an example of the correction curve. The correction curve determines in advance the correspondence between the opening command value output by the controller 7 to achieve the required air flow and the opening of the valve body 12 of the control valve device 10 when the required air flow is achieved, This is stored as data such as a relational expression or a correspondence table. In other words, the opening command value of the controller 7 is used as a substitute value (control basic value) of the required airflow.

  Further, since the correspondence relationship between the correction curves changes depending on the differential pressure before and after the valve element 12, a plurality of correction curves obtained by changing the differential pressure are stored. In the example of FIG. 14, the correction curves when the differential pressure ΔP is set to 100 Pa, 200 Pa, and 300 Pa, respectively, are obtained.

  FIG. 15 is an explanatory diagram of a control method of the control valve 1 according to the second embodiment. When the power is turned on, the control unit 2 operates the differential pressure recognition unit 22 and the processing unit 23 to execute the processing (control method) in FIG.

  First, the differential pressure recognition unit 22 detects a difference between the pressure on the front side of the valve body 12 transmitted via the front tube 131 and the pressure on the rear side of the valve body 12 transmitted via the rear tube 132, An electric signal corresponding to the differential pressure is input to the processing unit 23 (Step S11).

The processing unit 23 determines whether or not an opening signal (opening command value) as a control base value has been received from the controller 7 (step S12), and if the opening signal has been received (step S12, Yes).
Then, the correction curve (characteristic data) is read from the storage unit 21 (step S13), the opening of the valve body 12 corresponding to the opening signal is obtained based on the correction curve, and transmitted to the driving unit 24 as the opening signal ( Step S14).

  The driving unit 24 drives a driving source 241 such as a stepping motor based on the opening signal from the processing unit 23, and transmits the driving force of the driving source 241 to the rotation shaft 121 of the valve body 12 via the power transmission mechanism 242. By transmitting the rotation, the valve body 12 is rotated to adjust the opening degree indicated by the opening degree signal (step S15). The processing of steps S11 to S15 is repeatedly executed until the power is turned off.

  As described above, according to the second embodiment, the opening degree command value from the controller 7 is corrected based on the characteristic data to control the opening degree of the control valve. Even when the control valve 1 and the controller 7 of such a type are used in combination, appropriate control can be performed.

REFERENCE SIGNS LIST 1 control valve 2 control unit 4 air conditioner 5 constant air volume control device 6 room pressure gauge 7 controller 8 room 10 control valve device 11 main body 12 valve element 13 differential pressure tube 21 storage unit 22 differential pressure recognition unit 23 processing unit 24 drive unit 100 Air conditioning system

Claims (10)

Opening of a control valve that controls the flow rate or flow rate of the fluid by opening and closing the valve,
A control base value that is a value used for performing the control and is a flow rate of the fluid or a flow rate of the fluid that passes through the control valve, and
A storage unit that stores characteristic data indicating a relationship between the pressure difference before and after the valve of the fluid that passes through the control valve,
A differential pressure recognition unit that recognizes by detecting or calculating the differential pressure before and after the valve,
The differential pressure recognized by the differential pressure recognition unit and the control basic value required for control of the control valve are acquired from the storage unit or another device, and correspond to the acquired differential pressure and the control basic value required for the control. determined based on the opening degree of the control valve to the characteristic data, a position signal based on the opening, to force out the drive unit to operate the valve so that the opening degree based on the opening degree signal processing for example Bei and the processing section, the,
The processing unit, when the control base value required for the control is changed, until the control base value of the fluid passing through the control valve reaches the changed control base value required for the control, Repeating the output so that the operation is repeated,
Control valve control unit. Opening of a control valve that controls the flow rate or flow rate of the fluid by opening and closing the valve,
A control base value that is a value used for performing the control and is an opening command value that can be received from another device and operate the valve opening of the control valve, and
A storage unit that stores characteristic data indicating a relationship between the pressure difference before and after the valve of the fluid that passes through the control valve,
A differential pressure recognition unit that recognizes by detecting or calculating the differential pressure before and after the valve,
The differential pressure recognized by the differential pressure recognition unit and the control basic value required for control of the control valve are acquired from the storage unit or another device, and correspond to the acquired differential pressure and the control basic value required for the control. determined based on the opening degree of the control valve to the characteristic data, a position signal based on the opening, to force out the drive unit to operate the valve so that the opening degree based on the opening degree signal processing for example Bei and the processing section, the,
The processing unit, when the control base value required for the control is changed, the opening degree of the control valve corresponds to the changed control base value required for the control, the control valve obtained based on the characteristic data The output is repeated until the operation of the valve is repeated until the opening degree is reached.
Control valve control unit. Opening of a control valve that controls the flow rate or flow rate of the fluid by opening and closing the valve,
A control base value that is a value used for performing the control and is a flow rate of the fluid or a flow rate of the fluid that passes through the control valve, and
A storage unit that stores characteristic data indicating a relationship between the pressure difference before and after the valve of the fluid that passes through the control valve,
A differential pressure recognition unit that recognizes by detecting or calculating the differential pressure before and after the valve,
The differential pressure recognized by the differential pressure recognition unit and the control basic value required for control of the control valve are acquired from the storage unit or another device, and correspond to the acquired differential pressure and the control basic value required for the control. Determine the opening of the control valve based on the characteristic data, output an opening signal based on the opening, if the fluctuation of the differential pressure is recognized, the control base value of the fluid passing through the control valve A processing unit that repeats the output until the control base value required for the control is reached,
Control valve control unit. Opening of a control valve that controls the flow rate or flow rate of the fluid by opening and closing the valve,
A control base value that is a value used for performing the control and is an opening command value that can be received from another device and operate the valve opening of the control valve, and
A storage unit that stores characteristic data indicating a relationship between the pressure difference before and after the valve of the fluid that passes through the control valve,
A differential pressure recognition unit that recognizes by detecting or calculating the differential pressure before and after the valve,
The differential pressure recognized by the differential pressure recognition unit and the control basic value required for control of the control valve are acquired from the storage unit or another device, and correspond to the acquired differential pressure and the control basic value required for the control. The opening degree of the control valve is obtained based on the characteristic data, and an opening degree signal based on the opening degree is output. When the fluctuation of the differential pressure is recognized , the opening degree of the control valve is changed to the changed differential pressure. A processing unit that repeats the output until the opening degree of the control valve obtained based on the characteristic data is reached,
Control valve control unit. A control unit for the control valve according to any one of claims 1 to 4, comprising:
The control valve is:
A channel for the fluid,
The valve for controlling the flow rate of the fluid by opening and closing,
Transmitting means for transmitting the differential pressure before and after the valve to the differential pressure recognition unit,
Control valve device. An exhaust path exhausted from the air-conditioned space or an air supply path supplied to the air-conditioned space is provided with the control valve device according to claim 5.
Air conditioning system. Opening of a control valve that controls the flow rate or flow rate of the fluid by opening and closing the valve,
A control base value that is a value used for performing the control and is a flow rate of the fluid or a flow rate of the fluid that passes through the control valve, and
Reading the characteristic data from a storage unit storing characteristic data indicating a relationship between the pressure difference before and after the valve of the fluid passing through the control valve,
A step in which the differential pressure recognition unit recognizes by detecting or calculating the differential pressure before and after the valve,
A processing unit that obtains the differential pressure recognized by the differential pressure recognition unit and a control basic value required for controlling the control valve from the storage unit or another device, and obtains the acquired differential pressure and the control basic value required for the control. An opening degree of the control valve corresponding to the value is obtained based on the characteristic data, and an opening signal based on the opening degree is transmitted to a driving unit that operates the valve so as to have an opening degree based on the opening degree signal. output
Output comprising the steps of, a run,
In the output step, when the control base value required for the control is changed, the valve is controlled until the control base value of the fluid passing through the control valve reaches the changed control base value required for the control. The output is repeated so that the operation of is repeated,
Control valve control method. Opening of a control valve that controls the flow rate or flow rate of the fluid by opening and closing the valve,
A control base value that is a value used for performing the control and is an opening command value that can be received from another device and operate the valve opening of the control valve, and
Reading the characteristic data from a storage unit storing characteristic data indicating a relationship between the pressure difference before and after the valve of the fluid passing through the control valve,
A step in which the differential pressure recognition unit recognizes by detecting or calculating the differential pressure before and after the valve,
A processing unit that obtains the differential pressure recognized by the differential pressure recognition unit and a control basic value required for controlling the control valve from the storage unit or another device, and obtains the acquired differential pressure and the control basic value required for the control. An opening degree of the control valve corresponding to the value is obtained based on the characteristic data, and an opening signal based on the opening degree is transmitted to a driving unit that operates the valve so as to have an opening degree based on the opening degree signal. run and output step to output power, the,
In the output step, when the control base value required for the control is changed, the opening of the control valve is controlled based on the characteristic data, corresponding to the changed control base value required for the control. Until the opening of the valve is reached, the output is repeated so that the operation of the valve is repeated,
Control valve control method. Opening of a control valve that controls the flow rate or flow rate of the fluid by opening and closing the valve,
A control base value that is a value used for performing the control and is a flow rate of the fluid or a flow rate of the fluid that passes through the control valve, and
Reading the characteristic data from a storage unit storing characteristic data indicating a relationship between the pressure difference before and after the valve of the fluid passing through the control valve,
A step of recognizing the differential pressure by detecting or calculating the differential pressure before and after the valve,
A processing unit that obtains the differential pressure recognized by the differential pressure recognition unit and a control basic value required for controlling the control valve from the storage unit or another device, and obtains the acquired differential pressure and the control basic value required for the control. An opening degree of the control valve corresponding to the value is obtained based on the characteristic data, an opening degree signal based on the opening degree is output, and when the fluctuation of the differential pressure is recognized, the fluid passing through the control valve is output. Repeating the output until the control base value of the control reaches the control base value required for the control, and
Control valve control method. Opening of a control valve that controls the flow rate or flow rate of the fluid by opening and closing the valve,
A control base value that is a value used for performing the control and is an opening command value that can be received from another device and operate the valve opening of the control valve, and
Reading the characteristic data from a storage unit storing characteristic data indicating a relationship between the pressure difference before and after the valve of the fluid passing through the control valve,
A step of recognizing the differential pressure by detecting or calculating the differential pressure before and after the valve,
A processing unit that obtains the differential pressure recognized by the differential pressure recognition unit and a control basic value required for controlling the control valve from the storage unit or another device, and obtains the acquired differential pressure and the control basic value required for the control. An opening degree of the control valve corresponding to the value is obtained based on the characteristic data, an opening degree signal based on the opening degree is output, and when the fluctuation of the differential pressure is recognized , the opening degree of the control valve is changed . And an output step of repeating the output until the opening of the control valve obtained based on the characteristic data is reached , corresponding to the differential pressure .
Control valve control method.

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