Input / output module and control device

Abstract

The present disclosure relates to an input / output module capable of functioning as an input module or an output module through execution of control software. The input / output module comprises a transformer, a primary-side current detection unit, a primary-side voltage detection unit, a primary-side voltage control unit, and a transformer drive unit. The transformer includes a primary-side coil connected to an apparatus of a plant facility, and a secondary-side coil corresponding to the primary-side coil. The primary-side current detection unit detects a primary-side current flowing through the primary-side coil. The primary-side voltage detection unit detects a primary-side voltage applied to the primary-side coil. The primary-side voltage control unit controls the primary-side voltage, and the transformer drive unit drives the transformer on the basis of the primary-side voltage controlled by the primary-side voltage control unit. A secondary-side current flowing through the secondary-side coil is calculated on the basis of at least the primary-side current.

Description

Input / Output Module and Control Device

[0001] The present disclosure relates to an input / output module and a control device. This application claims priority based on Japanese Patent Application No. 2024-194252 filed with the Japan Patent Office on November 6, 2024, and incorporates its content herein by reference.

[0002] Plant facilities such as power generation plants are constructed including a number of components, and these components are controlled by a control device which is a control unit. This type of control device includes an arithmetic unit capable of executing control software for performing predetermined control processes, and an input / output module which is an interface for inputting and outputting various signals necessary for the control processes implemented by the arithmetic unit. The interfaces of the input / output module are designed according to its use, such as analog input (AI), analog output (AO), digital input (DI), digital output (DO), LVDT, frequency input, etc. For example, Patent Document 1 discloses a configuration related to an input module capable of inputting analog current from field devices as an example of this type of input / output module.

[0003] Patent No. 5293384

[0004] When modifying the control processes implemented by the control device, software-wise, it can be dealt with by rewriting the software installed in the control device. On the other hand, the input / output module of the control device has its hardware independently designed to correspond to various data handled by the installed control software as described above. Therefore, when the type or number of input / output signals handled by the control device is changed by rewriting the control software, it becomes necessary to newly develop the hardware of the control device including the input / output module. Such new development of hardware requires a great deal of time and cost.

[0005] At least one embodiment of the present disclosure has been made in view of the above circumstances, and an object thereof is to provide an input / output module and a control device that do not require hardware modification when rewriting control software.

[0006] An input / output module according to at least one embodiment of the present disclosure, in order to solve the above problems, is an input / output module that can function as an input module capable of receiving input signals from equipment of a plant facility, or as an output module capable of outputting output signals to the equipment, by the execution of control software, comprising: a transformer including a primary coil connected to the equipment and a secondary coil corresponding to the primary coil; a primary current detection unit for detecting the primary current flowing through the primary coil; a primary voltage detection unit for detecting the primary voltage applied to the primary coil; a primary voltage control unit for controlling the primary voltage; and a transformer drive unit for driving the transformer based on the primary voltage controlled by the primary voltage control unit, wherein the secondary current flowing through the secondary coil is calculated based on at least the primary current.

[0007] To solve the above problems, a control device according to at least one embodiment of the present disclosure comprises: an input / output module according to at least one embodiment of the present disclosure; and a calculation unit for controlling the plant equipment based on data transmitted and received with the input / output module by executing the control software.

[0008] According to at least one embodiment of this disclosure, it is possible to provide an input / output module and a control device that do not require hardware changes when the control software is rewritten.

[0009] This is a schematic diagram showing the overall configuration of a control system according to one embodiment. This is a schematic diagram showing the internal configuration of the input / output module in Figure 1. This is a flowchart showing an example of the operation process of the input / output module in Figure 2 in a control device with the first control software installed. This is a flowchart showing another example of the operation process of the input / output module in Figure 2 in a control device with the second control software installed.

[0010] Hereinafter, several embodiments of this disclosure will be described with reference to the attached drawings. However, the dimensions, materials, shapes, relative arrangements, etc., of the configurations described as embodiments or shown in the drawings are not intended to limit the scope of this disclosure, but are merely illustrative examples.

[0011] First, with reference to Figure 1, the overall configuration of the control system 1 according to at least one embodiment of this disclosure will be described. Figure 1 is a schematic diagram showing the overall configuration of the control system 1 according to one embodiment.

[0012] The control system 1 is a system having at least one control device 4 that controls plant equipment 2, such as a power plant. The plant equipment 2 is composed of various devices, and in Figure 1, one device 6 is typically shown as an example. The device 6 is not limited, but in this embodiment, it is, for example, a transmitter.

[0013] Furthermore, the control system 1 may have multiple control devices 4. In this case, these control devices 4 may perform control independently of each other, or they may perform control in conjunction (synchronized) with each other. Also, each of the multiple control devices 4 may control different devices 6, or they may control devices 6 that are at least partially common.

[0014] The control device 4 is a control unit that controls the device 6, and is composed of, for example, a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), and a computer-readable storage medium. In Figure 1, a typical configuration of the control device 4 is shown, which includes an arithmetic unit 10 that can perform predetermined arithmetic processing by executing pre-installed control software 8, and an input / output module 12 for inputting and outputting various information necessary for said arithmetic processing between the control device 6 and the control device. However, it may also appropriately include general configurations that electronic computing devices have within the scope of common technical knowledge (for example, an input unit, an output unit, or a storage unit).

[0015] The arithmetic unit 10 is configured to perform various calculations necessary for controlling the device 6 by executing control software 8 that is pre-installed on a storage medium or the like. Specifically, it performs calculation processing using data input from the device 6 via the input / output module 12, and can output control signals based on the calculation results obtained from the calculation processing to the device 6 via the input / output module 12.

[0016] The control software 8 executed by the arithmetic unit 10 is pre-stored in a storage medium (not shown), and the CPU constituting the arithmetic unit 10 reads this control software 8 into RAM or the like and performs information processing and calculations to realize various functions. The control software 8 may be pre-installed in ROM or other storage media, provided in a state where it is stored in a computer-readable storage medium, or distributed via wired or wireless communication means. Computer-readable storage media include magnetic disks, magneto-optical disks, CD-ROMs, DVD-ROMs, semiconductor memory, etc.

[0017] The input / output module 12 functions as an interface between the controlled device 6 and the arithmetic unit 10 in the control device 4. Specifically, it can transfer various data acquired from the device 6 to the arithmetic unit 10 as input data, and can also supply control signals received from the arithmetic unit 10 to the device 6 as output data.

[0018] In this case, the input / output module 12 is typically uniquely designed to accommodate the input / output data required by the control software 8 executed by the arithmetic unit 10. However, if the control software 8 is rewritten, a typical input / output module 12 cannot accommodate the input / output data required by the new control software 8. Therefore, the entire hardware of the control device 4, including the input / output module 12, must be newly developed, which requires a great deal of time and cost.

[0019] In contrast, the input / output module 12 according to this embodiment can handle the input / output data required by the new control software 8 even when the control software 8 is rewritten, as described below, thus eliminating the need for such new development. In other words, the input / output module 12 of this embodiment can handle the input / output data required by different control software 8 without changing the hardware configuration.

[0020] For convenience, in the following explanation, the control software 8 before rewriting will be referred to as "first control software 8a," and the control software 8 after rewriting will be referred to as "second control software 8b." The first control software 8a is an example of software that enables the input / output module 12 to function as an input module capable of performing an input current detection operation to detect the current (distribution current) input from the equipment 6 to the control device 4 (in this case, the input / output module 12 also functions as a constant voltage source to supply a constant voltage to each piece of equipment 6 of the plant equipment 2 connected to the control device 4). The second control software 8b, on the other hand, is an example of software that enables the input / output module 12 to function as an output module capable of performing a current output operation to output current to the equipment 6.

[0021] Next, the internal configuration of the input / output module 12 will be explained with reference to Figure 2. Figure 2 is a schematic diagram showing the internal configuration of the input / output module 12 shown in Figure 1.

[0022] The input / output module 12 includes a transformer 20. The transformer 20 includes a primary coil 20a and a secondary coil 20b. A low-pass filter 21, a primary current detection unit 22, a primary voltage detection unit 24, a primary voltage control unit 26, a transformer drive unit 28, and a primary current control capacitor C are connected to the primary coil 20a.

[0023] The primary current detection unit 22 is configured to detect the primary current I1 flowing through the primary coil 20a. In the primary current detection unit 22, the primary current I1 flowing through the primary coil 20a is input as an analog value via a low-pass filter 21. The low-pass filter 21 removes noise components contained in the primary current I1. The primary current detection unit 22 receives the primary current I1 from which the noise components have been removed by the low-pass filter 21, and the AD converter 23 converts it into a digital value, so that the detected value of the primary current I1 can be obtained as digital data.

[0024] The primary voltage detection unit 24 is configured to detect the primary voltage V1 applied to the primary coil 20a. In the primary voltage detection unit 24, the primary voltage V1 applied to the primary coil 20a is input as an analog value via a low-pass filter 21. The low-pass filter 21 removes noise components contained in the primary voltage V1. The primary voltage detection unit 24 receives the primary voltage V1 from which the noise components have been removed by the low-pass filter 21, and converts it into a digital value by the AD converter 25, thereby enabling the acquisition of the detected value of the primary voltage V1 as digital data.

[0025] Furthermore, the primary current I1 detected by the primary current detection unit 22 and the primary voltage V1 detected by the primary voltage detection unit 24 are input to the calculation unit 10 (see Figure 1), respectively, and can be used for various calculation processes executed by the control software 8.

[0026] The primary voltage control unit 26 is configured to control the primary voltage V1 of the transformer 20. Specifically, the primary voltage control unit 26 controls the primary voltage V1 so that the estimated value of the secondary current I2 or secondary voltage V2, calculated in the calculation unit 10 based on at least one of the primary current I1 detected by the primary current detection unit 22 or the primary voltage V1 detected by the primary voltage detection unit 24, becomes a predetermined target value.

[0027] The transformer drive unit 28 is configured to drive the transformer 20 based on the primary voltage V1 controlled by the primary voltage control unit 26.

[0028] The device 6, which is the control target of the control device 4, is connected to the secondary coil 20b of the transformer 20 via a secondary current rectifier 30 and a secondary protection circuit 32. The secondary current rectifier 30 is configured to rectify the secondary current I2 flowing through the secondary coil 20b of the transformer 20. The secondary protection circuit 32 is configured to protect the device 6 connected to the input / output module 12 from excessive secondary current I2 or secondary voltage V2.

[0029] Next, the specific operation of the input / output module 12 in the control device 4 having the above configuration will be described. The operation of the input / output module 12 is switched according to the type of control software 8 installed in the control device 4, thereby enabling it to handle input / output data required by different control software 8.

[0030] First, we will describe the operation of the input / output module 12 in the control device 4, which is equipped with first control software 8a, which implements control functions including input current detection operation for detecting input current (distribution current) from the device 6. In this case, the input / output module 12 functions as an input module. Figure 3 is a flowchart showing an example of the operation process of the input / output module 12 in Figure 2 in the control device 4 equipped with first control software 8a.

[0031] First, in the input / output module 12, the primary voltage detection unit 24 detects the primary voltage V1 of the transformer 20 (step S100). In the primary voltage detection unit 24, the analog value of the primary voltage V1 input from the primary coil 20a of the transformer 20 is input to the AD converter 25 via the low-pass filter 21, and the AD converter 25 converts it to a digital value, thereby detecting the primary voltage V1 as digital data. The primary voltage V1 detected in this way by the primary voltage detection unit 24 is input to the calculation unit 10 on which the first control software 8a is installed.

[0032] Next, the primary current detection unit 22 detects the primary current I1 of the transformer 20 (step S101). In the primary current detection unit 22, the analog value of the primary current I1 input from the primary coil 20a of the transformer 20 is input to the AD converter 23 via the low-pass filter 21, and the AD converter 23 converts it to a digital value, thereby detecting the primary current I1 as digital data. The primary current I1 detected in this way by the primary current detection unit 22 is input to the calculation unit 10 on which the first control software 8a is installed.

[0033] Next, the calculation unit 10 calculates an estimated value of the secondary current I2 based on the primary voltage V1 input in step S100 and the primary current I1 input in step S101 (step S102).

[0034] Here, we will specifically explain the method for calculating the estimated value of the secondary current I2, which is performed by the calculation unit 10 in step S102. First, as a simple calculation method, there is a calculation method based on Faraday's law. Using the primary current I1 detected by the primary current detection unit 22 and the winding ratio R of the transformer (if the number of turns of the primary coil 20a is M1 and the number of turns of the secondary coil 20b is M2, then R = M1 / M2), the estimated value of the secondary current I2 is calculated by the following formula: I2 = I1 × R (1)

[0035] The calculation method using Faraday's law as shown in equation (1) above does not take into account the iron loss, copper loss, and heat loss in the surrounding circuitry of the actual transformer 20, so the accuracy of the calculation of the secondary current I2 may not be sufficient. In this case, the secondary current I2 may be calculated using the statistical method described below.

[0036] In the statistical method, the primary current I1, primary voltage V1, and secondary current I2 are measured (actually measured) for each state in which the load and current values ​​applied to the device 6 are changed, thereby determining in advance the correlation between the secondary current I2 and the primary current I1 and primary voltage V1. This correlation can be expressed using a function fx, for example, as shown in the following equation: I2 = fx(I1, V1) (2) In this case, in step S102, the primary current I1 detected by the primary current detection unit 22 in step S101 and the primary voltage V1 detected by the primary voltage detection unit 24 in step S100 are input to the above function fx, thereby determining the corresponding secondary current I2.

[0037] In this example, the correlation between the secondary current I2 and the primary current I1 and primary voltage V1 is shown as a function fx, but it may also be specified as a table showing this correlation.

[0038] The estimated value of the secondary current I2 calculated in step S102 is treated in the calculation unit 10 as an input detection value from the device 6 in the input / output module 12 which functions as an input module, and becomes available for various calculation processes (step S103).

[0039] Furthermore, in the calculation unit 10, an estimated value of the secondary voltage V2 is calculated based on the primary voltage V1 input in step S100 and the primary current I1 input in step S101 (step S104). Specifically, using the number of turns M1 of the primary coil 20a and the number of turns M2 of the secondary coil 20b of the transformer 20, the relationship between the primary voltage V1 and the secondary voltage V2 is given by the following equation: V1 / V2 = M1 / M2 (3) Therefore, if the primary load (combined resistance) of the transformer 20 is R1, the estimated value of the secondary voltage V2 is calculated by the following equation: V2 = M2 / M1 × I1 × R1 (4)

[0040] Next, the primary voltage control unit 26 controls the primary voltage V1 so that the estimated value of the secondary voltage V2 calculated in step S104 becomes a certain target voltage value (a predetermined power supply voltage value) (step S105).

[0041] When the first control software 8a is executed in the arithmetic unit 10 as described above, the input / output module 12 can detect the input current (distribution current) from the device 6 and function as an input module capable of supplying a constant voltage as the power supply voltage to the device 6.

[0042] Next, a case where the control software 8 executed by the arithmetic unit 10 is rewritten to the second control software 8b for realizing control processing including a current output operation for outputting current to the device 6 will be described. In this case, the input / output module 12 functions as an output module. FIG. 4 is a flowchart showing another example of the operation process of the input / output module 12 in FIG. 2 in the control device 4 in which the second control software 8b is installed.

[0043] First, in the input / output module 12, the primary-side voltage V1 of the transformer 20 is detected by the primary-side voltage detection unit 24 (step S200). In the primary-side voltage detection unit 24, the analog value of the primary-side voltage V1 input from the primary-side coil 20a of the transformer 20 is input to the AD converter 25 via the low-pass filter 21, and is converted into a digital value by the AD converter 25, whereby the primary-side voltage V1 is detected as digital data. The primary-side voltage V1 thus detected by the primary-side voltage detection unit 24 is input to the arithmetic unit 10 in which the second control software 8b is installed as the control software 8.

[0044] Subsequently, the primary-side current I1 of the transformer 20 is detected by the primary-side current detection unit 22 (step S201). In the primary-side current detection unit 22, the analog value of the primary-side current I1 input from the primary-side coil 20a of the transformer 20 is input to the AD converter 23 via the low-pass filter 21, and is converted into a digital value by the AD converter 23, whereby the primary-side current I1 is detected as digital data. The primary-side current I1 thus detected by the primary-side current detection unit 22 is input to the arithmetic unit 10 in which the second control software 8b is installed as the control software 8.

[0045] Subsequently, in the arithmetic unit 10, an estimated value of the secondary current I2 is calculated based on the primary voltage V1 detected in step S200 and the primary current I1 detected in step S200 (step S202). The calculation of the secondary current I2 in step S202 can be performed in the same manner as in step S102 described above.

[0046] Subsequently, the primary voltage control unit 26 acquires a secondary current target value It2, which is an output target value of the secondary current I2 (step S203), and controls the primary voltage V1 so that the estimated value of the secondary current I2 calculated in step S202 becomes the secondary current target value It2 acquired in step S203 (step S204).

[0047] When the second control software 8b is executed in the arithmetic unit 10 in this way, the input / output module 12 can function as an output module capable of outputting a predetermined current to the device 6.

[0048] As described above, according to the above embodiment, without changing the hardware configuration of the input / output module 12, by rewriting the control software 8 installed in the arithmetic unit 10 to the first control software 8a or the second control software 8b, an input / output module capable of functioning as an input module or an output module can be realized.

[0049] In addition, without departing from the spirit of the present disclosure, it is possible to appropriately replace the components in the above-described embodiment with well-known components, and the above-described embodiments may be appropriately combined.

[0050] The content described in each of the above embodiments is understood as follows, for example.

[0051] (1) An input / output module according to one embodiment is an input / output module that can function as an input module capable of receiving input signals from equipment of a plant facility, or as an output module capable of outputting output signals to the equipment, by the execution of control software, comprising: a transformer including a primary coil connected to the equipment and a secondary coil corresponding to the primary coil; a primary current detection unit for detecting the primary current flowing through the primary coil; a primary voltage detection unit for detecting the primary voltage applied to the primary coil; a primary voltage control unit for controlling the primary voltage; and a transformer drive unit for driving the transformer based on the primary voltage controlled by the primary voltage control unit, wherein the secondary current flowing through the secondary coil is calculated based on at least the primary current.

[0052] According to the embodiment described in (1) above, an input / output module capable of functioning as an input module or an output module is obtained by the control software being executed. This input / output module detects the primary current or primary voltage of the transformer, and calculates the secondary current computationally based on at least the primary current. When the input / output module functions as an input module, the secondary current is treated as the input detection value. On the other hand, when the input / output module functions as an output module, the output value can be controlled based on the secondary current. Thus, with this configuration, an input / output module capable of functioning as an input module or an output module can be realized by control software under a common hardware configuration.

[0053] (2) In another embodiment, in the embodiment of (1) above, the secondary current is calculated based on the primary current and the winding ratio of the transformer.

[0054] According to the embodiment of (2) above, the value of the secondary current flowing through the secondary coil of the transformer can be easily determined using the winding ratio of the transformer.

[0055] (3) In other embodiments, in the embodiment of (1) or (2) above, the secondary current is calculated based on the correlation with the primary current and the primary voltage.

[0056] According to the embodiment of (3) above, by pre-determining the correlation between the primary current and primary voltage and the secondary current, the secondary current can be accurately determined based on the primary current and primary voltage detected in the primary coil of the transformer.

[0057] (4) In other embodiments, in any one embodiment of (1) to (3) above, the input module functions as capable of detecting the secondary current as the input current from the device.

[0058] According to the embodiment of (4) above, an input module having the above configuration can be realized that can acquire a secondary current calculated computationally based on at least the primary current as an input detection value.

[0059] (5) In another embodiment, in the embodiment of (4) above, the secondary voltage is calculated based on the primary current and the primary voltage, and the primary voltage control unit controls the primary voltage so that the secondary voltage becomes the output target value.

[0060] According to the embodiment of (5) above, when the input / output module is used as an input module, a predetermined voltage can be supplied to the equipment by controlling the secondary voltage of the transformer, which is calculated based on the primary current and primary voltage, so that it becomes the output target value.

[0061] (6) In other embodiments, the output module functions as an output module capable of supplying the secondary current as an output current to the device in any one embodiment of (1) to (5) above.

[0062] According to the embodiment of (6) above, an output module can be realized in an input / output module having the above configuration that is capable of outputting a secondary current calculated computationally based on at least the primary current.

[0063] (7) In another embodiment, in the embodiment of (6) above, the primary voltage control unit controls the primary voltage so that the secondary current becomes the output target value.

[0064] According to the embodiment of (7) above, by controlling the primary voltage so that the secondary current calculated based on at least the primary current becomes the output target value, an output module capable of outputting a predetermined current can be suitably realized.

[0065] (8) A control device according to one embodiment comprises an input / output module as described in any one of (1) to (7) above, and a calculation unit for controlling the plant equipment based on data transmitted and received with the input / output module by executing the control software.

[0066] According to the embodiment of (8) above, by inputting and outputting various data with the equipment using the input / output module, the control unit can suitably realize control of plant equipment using this data by executing control software. The control software executed in the control unit can be rewritten as needed, and when the control software is rewritten, it is possible to handle the data input and output in accordance with the new control software without changing the hardware of the control device. As a result, new hardware development is not required in response to changes in the control software, and the time and cost required for development can be suitably reduced.

[0067] (9) In other embodiments, in the embodiment of (8) above, the control software is a first control software for controlling the plant equipment using the input current from the equipment detected by the input / output module by causing the input / output module to function as the input module, or a second control software for supplying output current from the input / output module to the equipment in order to control the plant equipment by causing the input / output module to function as the output module.

[0068] According to the embodiment of (9) above, by making the control software executed in the control unit the first control software, the input / output module can function as an input module, while by making the control software executed in the control unit the second control software, the input / output module can function as an output module. As a result, by rewriting the control software to either the first control software or the second control software, it is possible to provide an input / output module that can function as an input module or an output module as needed without requiring a change in the hardware configuration design.

[0069] 1 Control system 2 Plant equipment 4 Control device 6 Equipment 8 Control software 10 Calculation unit 12 Input / output module 20 Transformer 20a Primary coil 20b Secondary coil 21 Low-pass filter 22 Primary current detection unit 24 Primary voltage detection unit 26 Primary voltage control unit 28 Transformer drive unit 30 Secondary current rectification unit 32 Secondary protection circuit C Primary current control capacitor

Claims

1. An input / output module capable of functioning as an input module capable of receiving input signals from equipment in a plant facility, or as an output module capable of outputting output signals to said equipment, by the execution of control software, comprising: a transformer including a primary coil connected to said equipment and a secondary coil corresponding to said primary coil; a primary current detection unit for detecting the primary current flowing through said primary coil; a primary voltage detection unit for detecting the primary voltage applied to said primary coil; a primary voltage control unit for controlling said primary voltage; and a transformer drive unit for driving said transformer based on the primary voltage controlled by said primary voltage control unit, wherein the secondary current flowing through said secondary coil is calculated based on at least said primary current.

2. The input / output module according to claim 1, wherein the secondary current is calculated based on the primary current and the winding ratio of the transformer.

3. The input / output module according to claim 1 or 2, wherein the secondary current is calculated based on the correlation with the primary current and the primary voltage.

4. The input / output module according to claim 1 or 2, which functions as the input module capable of detecting the secondary current as the input current from the device.

5. An input / output module according to claim 4, comprising: calculating a secondary voltage based on the primary current and the primary voltage; and controlling the primary voltage by the primary voltage control unit so that the secondary voltage becomes an output target value.

6. The input / output module according to claim 1 or 2, which functions as the output module capable of supplying the secondary current as the output current to the device.

7. The input / output module according to claim 6, wherein the primary voltage control unit controls the primary voltage so that the secondary current becomes an output target value.

8. A control device comprising: an input / output module according to claim 1 or 2; and a calculation unit for controlling the plant equipment based on data transmitted and received with the input / output module by executing the control software.

9. The control device according to claim 8, wherein the control software is a first control software for controlling the plant equipment using the input current from the equipment detected by the input / output module by causing the input / output module to function as the input module, or a second control software for supplying output current from the input / output module to the equipment in order to control the plant equipment by causing the input / output module to function as the output module.

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