Fault assessment device, fault assessment method, and program

Abstract

The present invention provides a fault assessment method for achieving reliable equipment protection. This fault assessment device comprises: a command unit that outputs a control command value to a device to be controlled; an acquisition unit that acquires an operating state value from the device to be controlled; and a fault assessment unit that assesses a fault to have occurred when a state in which the outputted control command value and the acquired operating state value deviate by at least a predetermined threshold value continues for at least a predetermined standby time. The fault assessment unit assesses the fault on the basis of a previous deviation between the control command value and the control command value by a predetermined delay time.

Description

Abnormal determination device, abnormal determination method, and program

[0001] The present disclosure relates to an abnormal determination device, an abnormal determination method, and a program. The present disclosure claims priority based on Japanese Patent Application No. 2024-172483 filed in Japan on October 1, 2024, and incorporates its content herein by reference.

[0002] When the control of major control components of a turbine, such as a fuel control valve, a steam control valve, an IGV (inlet air guide vane), and a combustor bypass valve, is lost, it becomes difficult to operate the turbine stably, and equipment damage may occur. For example, Patent Document 1 discloses a technique in which when a state where the deviation between the opening degree commanded by a control device of a steam turbine and the actual opening degree deviates from a threshold value by a certain amount or more continues for a certain period of time or more, it is determined as abnormal, an alarm is issued, and the turbine is tripped. If the state where the commanded opening degree value and the actual opening degree deviate from each other is left for a certain period of time or more for abnormal determination, depending on the length of that time, it may become impossible to protect the equipment.

[0003] Japanese Patent Laid-Open No. 63-105204

[0004] In a technique that determines abnormality when a state where the commanded opening degree value and the actual opening degree deviate from each other continues for a certain standby time or more, it is desirable to shorten that standby time.

[0005] The present disclosure provides an abnormal determination device, an abnormal determination method, and a program that can solve the above problems.

[0006] According to one aspect of the present disclosure, an abnormal determination device includes a command unit that outputs a control command value to a controlled device, an acquisition unit that acquires an operating state value of the controlled device, and an abnormal determination unit that determines abnormality when a state where the deviation between the control command value and the operating state value deviates from a predetermined threshold value or more continues for a predetermined standby time or more. The abnormal determination unit makes the determination of the abnormality based on the deviation between the operating state value acquired at a certain time and the control command value at a time that is a predetermined delay time before that time.

[0007] According to one aspect of the present disclosure, an abnormality determination method is an abnormality determination method performed by an abnormality determination device, comprising the steps of: outputting a control command value to a controlled device; acquiring an operating status value of the controlled device; and determining that an abnormality exists if the deviation between the control command value and the operating status value exceeds a predetermined threshold and continues for a predetermined waiting time or longer, wherein the abnormality determination step is performed based on the deviation between the operating status value acquired at a certain time and the control command value that has been in the past for a predetermined delay time from that time.

[0008] According to one aspect of the present disclosure, the program includes the steps of: outputting a control command value to a device to be controlled; acquiring an operating status value of the device to be controlled; and determining that an abnormality exists if the deviation between the control command value and the operating status value exceeds a predetermined threshold for a predetermined waiting period of time or longer, wherein the step of determining an abnormality involves causing the computer to execute a process that determines the abnormality based on the deviation between the operating status value acquired at a certain time and the control command value that was acquired at a predetermined delay time earlier than that time.

[0009] According to the abnormality detection device, abnormality detection method, and program described above, in a technology that determines an abnormality when the state in which the opening degree command value and the actual opening degree deviate from each other continues for a certain waiting period or longer, the waiting period can be shortened.

[0010] This is a schematic diagram of the system to be monitored according to the embodiment. This is a diagram showing an example of the control logic according to the embodiment. This is a diagram showing an example of the waiting time according to the embodiment. This is a flowchart showing an example of the abnormality detection process according to the embodiment. This is a diagram showing an example of the hardware configuration of the control device according to the embodiment.

[0011] <Embodiment> The abnormality detection method according to this embodiment will be described below with reference to the drawings. (System Configuration) Figure 1 is a schematic diagram of the system to be monitored according to the embodiment. Figure 1 shows a part of the system provided by equipment 100. Equipment 100 is various equipment such as steam turbines, gas turbines, nuclear power plants, chemical plants, and boilers. Equipment 100 has a redundant configuration of system 1 and system 2. System 1 is the operational side, and system 2 is the standby side. The fluid flowing through system 1 is supplied to equipment 3. Valve V1 is provided in system 1. If a failure occurs in system 1, it switches to system 2, and the fluid supplied from the upstream side is supplied to equipment 3 through system 2. Valve V2 is provided in system 2.

[0012] The control device 10 controls valves V1 and V2. The control device 10 includes an instruction unit 11, a monitoring unit 12, and an abnormality determination unit 13. The instruction unit 11 determines the opening degree command value for valves V1 and V2, commands valves V1 and V2 with the determined opening degree command value, and outputs the opening degree command value to the abnormality determination unit 13. Regardless of whether system 1 or system 2 is the operating side, the same opening degree command value is commanded to valves V1 and V2.

[0013] The monitoring unit 12 acquires the opening degree (referred to as the actual opening degree) of valves V1 and V2. For example, valves V1 and V2 are equipped with sensors that detect the opening degree, and the monitoring unit 12 acquires the opening degree detected by these sensors. Regardless of whether system 1 or system 2 is the operating side, the monitoring unit 12 acquires the actual opening degrees of valves V1 and V2. The monitoring unit 12 outputs the acquired actual opening degrees of valves V1 and V2 to the abnormality determination unit 13.

[0014] The abnormality determination unit 13 compares the opening degree command value output by the instruction unit 11 with the actual opening degree of valve V1 acquired by the monitoring unit 12. If the deviation between the opening degree command value and the actual opening degree remains above a threshold for a predetermined waiting time or longer, the unit determines that an abnormality has occurred in valve V1. The same applies to valve V2. At this time, there is a delay between the time the instruction unit 11 determines the opening degree command values ​​for valves V1 and V2 and the time valves V1 and V2 actually open to the opening degree of the opening degree command value, due to the processing time and control delay time within the control device 10. Conventionally, sufficient time was often set for the waiting time to account for these delays. However, if the waiting time is too long, the condition of the equipment 100 may deteriorate during that time, and equipment protection may be compromised. Therefore, in this embodiment, the waiting time is set to be as short as possible in order to determine abnormalities more quickly while avoiding false detections, etc.

[0015] Figure 2 shows an example of the abnormality determination logic provided by the abnormality determination unit 13. The abnormality determination unit 13 includes a dead time element 133, a deviation calculation element 134, a deviation calculation element 135, a high / low monitor 136, a high / low monitor 137, an OR element 138, an on-delay time element 139, and a deviation detection element 140. The abnormality determination unit 13 acquires the opening degree command value 130 output by the instruction unit 11, the actual opening degree 131 of valve V1 acquired by the monitoring unit 12, and the actual opening degree 132 of valve V2. The abnormality determination unit 13 outputs the acquired opening degree command value 130 to the dead time element 133. The dead time element 133 outputs the acquired opening degree command value 130 with a predetermined delay time L. For example, the dead time element 133 calculates e - Ls using a predetermined delay time L and outputs a signal of the opening degree command value 130 delayed by the delay time L to the deviation calculation element 134. Here, L is dead time (delay time) and s is the Laplace operator. For example, the delay time L is the sum of the processing time from when the opening degree command value is calculated (determined) until it is output and the time from when the opening degree command value is output until valves V1 and V2 actually start operating according to the opening degree command value. Alternatively, the delay time L is the time from when the opening degree command value is output until valves V1 and V2 actually start operating according to the opening degree command value. On the other hand, the abnormality determination unit 13 outputs the acquired actual opening degree 131 of valve V1 to the deviation calculation element 134. The deviation calculation element 134 receives the actual opening degree 131 of valve V1 and the opening degree command value 130 that was commanded in the past by the delay time L as input. The deviation calculation element 134 receives the previously commanded opening degree value 130 and the actual opening degree at each moment since the time when valve V1 starts operating as a result of that opening degree command value 130. The deviation calculation element 134 calculates the deviation between the actual opening degree 131 and the opening degree command value 130, and outputs the calculated deviation to the high / low monitor 136. The high / low monitor 136 outputs an ON signal if the deviation between the opening degree command value 130 for valve V1 and the actual opening degree 131 of valve V1 exceeds the upper or lower limit. The high / low monitor 136 outputs an OFF signal if the deviation does not exceed the upper or lower limit. The high / low monitor 136 also outputs an OFF signal if system 1 is not the operating side. The ON signal and OFF signal are output to the OR element 138.

[0016] The abnormality detection unit 13 outputs the acquired actual opening degree 132 of valve V2 to the deviation calculation element 135. The deviation calculation element 135 receives the actual opening degree 132 of valve V2 and the opening degree command value 130 that was commanded in the past by a delay time L. The deviation calculation element 135 receives the opening degree command value 130 that was commanded in the past by a delay time L and the actual opening degree 132 at each moment since the time when valve V2 started to operate as a result of that opening degree command value 130. The deviation calculation element 135 calculates the deviation between the actual opening degree 132 of valve V2 and the opening degree command value 130 and outputs the calculated deviation to the high / low monitor 137. The high / low monitor 137 outputs an ON signal if the deviation between the actual opening degree 132 of valve V2 and the opening degree command value 130 exceeds the upper or lower limit. The high / low monitor 137 outputs an OFF signal if the deviation does not exceed the upper or lower limit. Even when system 2 is not the operational side, the high / low monitor 136 outputs an off signal. The on signal and off signal are output to the OR element 138.

[0017] The OR element 138 acquires an ON signal or an OFF signal from the high / low monitor 136 and the high / low monitor 137, respectively, and outputs an ON signal if either is an ON signal. The ON signal is output to the ON delay time element 139. The ON delay time element 139 outputs an ON signal to the deviation detection element 140 if it continues to acquire an ON signal for a predetermined waiting time after the signal acquired from the OR element 138 changes from an OFF signal to an ON signal. Otherwise, the ON delay time element 139 outputs an OFF signal to the deviation detection element 140. When the deviation detection element 140 receives an ON signal, the abnormality determination unit 13 determines that an abnormality has occurred and outputs, for example, a trip signal. When a trip signal is output, the control device 10 stops the equipment 100. Alternatively, the abnormality determination unit 13 may issue an alarm if it determines that an abnormality has occurred.

[0018] To elaborate on the control logic in Figure 2, if a discrepancy of more than a threshold occurs between the actual opening degree and the opening command value of valve V1 for a period of time, the system is controlled to switch to system 2. If, after switching to system 2, there is no discrepancy of more than a threshold between the actual opening degree and the opening command value of valve V2, an off signal is output from both the high / low monitor 136 and the high / low monitor 137, and no abnormality is detected. If the discrepancy of more than a threshold occurs between the actual opening degree and the opening command value of system 1 continues for a period of time, and if the discrepancy of more than a threshold occurs between the actual opening degree and the opening command value of valve V2 continues for a certain period of time even after switching to system 2, an abnormality is detected. The waiting time is set to allow detection of continued abnormalities in system 1 and system 2 after the switch.

[0019] As described above, the dead time element 133 outputs the opening degree command value 130 with a delay of L from the time the opening degree command value is calculated or output until valves V1 and V2 start operating according to the opening degree command value. In contrast, the waiting time is set to the time from when valves V1 and V2 start operating until they achieve the opening degree indicated by the opening degree command value. If there are no problems with valves V1 and V2, the opening degree of valves V1 and V2 should reach the opening degree indicated by the opening degree command value after the time calculated by "delay time L + waiting time" has elapsed from the time the opening degree command value is calculated. Therefore, by setting the time required for valve operation in the waiting time, the waiting time will not be too short, and valve abnormality detection can be performed without problems. By setting the time required for valve operation in the waiting time, the concern that the time until an abnormality is determined to be longer than necessary can be eliminated.

[0020] Figure 3 shows an example of a waiting time. Item 1 in Figure 3 is an example of setting the waiting time to T + α. T is the time required for the valve to go from fully open to fully closed (or from fully closed to fully open). α is a buffer time set to account for individual differences, noise, and to prevent false detections. T can be determined from the valve specifications (for example, within 1 second). α should be set to a value that does not diminish the purpose of shortening the waiting time (for example, within 0.5 seconds). By setting T to the time required for the valve to go from fully open to fully closed, the opening degree indicated by the opening degree command value can be achieved within the waiting time T + α, regardless of the current opening degree of valves V1 and V2 or the next commanded opening degree command value.

[0021] Items 2 and 3 are examples of setting the waiting time according to the current opening degree. Item 2 is an example where the current opening degree is 50%. If the current opening degree is 50%, even if the next opening degree command is 0% or 100%, the opening degree command value can be achieved by operating for a maximum of 50% of the entire stroke (the process of operating the valve from fully closed to fully open). Here, the time required for opening and closing for 50% is about 50% of the time required for the entire stroke. Therefore, if the current opening degree is 50%, any opening degree command value can be handled with half the time required for the entire stroke. Based on this idea, when the current opening degree is 50%, the waiting time is set to 0.5 × T + α. Item 3 is an example where the current opening degree is 70%. If the current opening degree is 70%, then if the next opening degree command is 0%, then 70% of the entire stroke is required, and if the next opening degree command value is 100%, then 30% of the entire stroke is required. In this case, following the same reasoning as in item 2, the waiting time is set to 0.7 × T + α.

[0022] Items 4 and 5 are examples of setting the waiting time according to the current opening degree and the opening degree command value. Item 4 is an example where the current opening degree is 50% and the opening degree command value is 30%. In this case, the time required to change the opening degree from 50% to 30% is about 20% of the total process, so the waiting time is set to 0.2 × T + α. Item 6 is an example where the current opening degree is 50% and the opening degree command value is 80%. In this case, the time required to change the opening degree from 50% to 80% is about 30% of the total process, so the waiting time is set to 0.3 × T + α. By setting the waiting time based on this way of thinking, the waiting time can be shortened.

[0023] (Operation) Next, the abnormality detection process of this embodiment will be described. Figure 4 is a flowchart showing an example of the abnormality detection process according to the embodiment. Assume that the control device 10 has been set in advance to determine which of the following methods (a) to (c) will determine the waiting time. (a) Set the waiting time based on the operation of the entire stroke of valves V1 and V2 (item 1 in Figure 3), (b) Set the waiting time based on the opening degree of valves V1 and V2 (items 2 and 3 in Figure 3), (c) Set the waiting time based on the opening degree of valves V1 and V2 and the opening degree command value (items 4 and 5 in Figure 3).

[0024] The abnormality detection unit 13 acquires the actual opening degree of valves V1 and V2 (step S1). The abnormality detection unit 13 acquires past opening degree command values ​​for a delay time L (step S2). Steps S1 and S2 are executed simultaneously and continuously. The abnormality detection unit 13 retains (stores) the acquired actual opening degree and opening degree command values ​​for a certain period of time.

[0025] Next, the abnormality determination unit 13 determines whether the deviation between the actual opening degree obtained in step S1 and the opening degree command value obtained in step S2 by the past delay time L is greater than or equal to a threshold (step S3). If the deviation is less than the threshold (step S3; No), the process returns to step S1. If the deviation is greater than or equal to the threshold (step S3; Yes), the abnormality determination unit 13 determines whether the state in which the deviation is greater than or equal to the threshold has continued for longer than the waiting time (step S4). In making this determination, the abnormality determination unit 13 first sets the waiting time. In case (a), the abnormality determination unit 13 calculates the waiting time by adding a reserve time α to the time T required for the operation of the entire stroke of valves V1 and V2 (assuming that the specifications of valves V1 and V2 are the same), regardless of the actual opening degree or the opening degree command value. In case (a), there is no need to calculate the waiting time; T + α should be set in the control device 10 in advance. In case (b), the abnormality determination unit 13 selects from the actual opening degrees that have been held for a certain period of time, which are the actual opening degrees before a change of a predetermined value or more occurs in the opening degree command value (or, in cases where there is no change in the opening degree command value but the actual opening degree has changed by a predetermined value or more), calculates how much the selected actual opening degree needs to be changed to accommodate all opening degree command values, and adds α to the calculation result to calculate the waiting time. Specifically, it selects the larger number between (100% - selected actual opening degree) and (selected actual opening degree - 0%), calculates (selected number ÷ 100) × T + α, and sets the calculation result as the waiting time. In case (c), the abnormality determination unit 13 selects from the actual opening degrees that have been held for a certain period of time, such as before a change in the opening degree command value, selects from the opening degree command values ​​that have been held for a certain period of time, which are the opening degree after the change, and calculates the time required for the opening degree change corresponding to the difference between the two. Specifically, it calculates (difference between the two ÷ 100) × T + α and sets the calculation result as the waiting time. If the first determination in step S4 is Yes, a flag is set, and the waiting time is not updated until the next determination in step S4 is No, maintaining the set waiting time. If the condition in which the deviation is greater than or equal to the threshold does not continue for longer than the waiting time (step S4; No), the process returns to step S1. If it continues for longer than the waiting time (step S4; Yes), the abnormality determination unit 13 determines that an abnormality has occurred (step S5). When the abnormality determination unit 13 determines that an abnormality has occurred, it outputs a signal to instruct an alarm or to stop the equipment 100.

[0026] (Effects) As explained above, according to this embodiment, the idle time element 133 allows for a comparison between the opening degree command value, which has been delayed by a delay time L from the time of determination, and the actual opening degree in real time. This reduces the time from the determination of the opening degree command value to the start of valve operation, which is used to determine an abnormality when the discrepancy between the opening degree command value and the actual opening degree persists for a period longer than the waiting time, thereby shortening the waiting time. By setting the waiting time to a time corresponding to the amount of valve opening and closing operation, it is possible to secure the minimum time necessary for abnormality determination while avoiding setting an unnecessarily long waiting time, thereby shortening the waiting time. By shortening the waiting time, abnormality determination can be performed without leaving the discrepancy between the opening degree command value and the actual opening degree unattended, thus ensuring more reliable equipment protection compared to conventional abnormality determination processes.

[0027] In the above embodiment, the case of a redundant configuration of system 1 and system 2 was described as an example, but abnormality detection according to this embodiment is also possible for monitoring equipment with only one system (for example, system 1 only). For example, abnormality detection of system 1 can be performed by removing the actual opening degree 132 of system 2, the deviation calculation element 135, the high / low monitor 137, and the OR element 138 from the control logic of Figure 2, and connecting the high / low monitor 136 and the on-delay time element 139.

[0028] Figure 5 shows an example of the hardware configuration of the control device 10 according to the embodiment. The computer 900 includes a CPU 901, main memory 902, auxiliary storage 903, input / output interface 904, and communication interface 905. The control device 10 described above is implemented in the computer 900. The functions described above are stored in the auxiliary storage 903 in the form of a program. The CPU 901 reads the program from the auxiliary storage 903, expands it in the main memory 902, and executes the above processing according to the program. The CPU 901 allocates a storage area in the main memory 902 according to the program. The CPU 901 also allocates a storage area in the auxiliary storage 903 to store the data being processed according to the program.

[0029] A program for realizing all or part of the functions of the control device 10 may be recorded on a computer-readable recording medium, and the program recorded on this recording medium may be loaded into a computer system and executed to perform processing by each functional unit. Here, "computer system" includes hardware such as the OS and peripheral devices. If a WWW system is used, "computer system" also includes the homepage provisioning environment (or display environment). "Computer-readable recording medium" refers to portable media such as CDs, DVDs, USBs, and storage devices such as hard disks built into the computer system. If this program is distributed to the computer 900 via a communication line, the computer 900 that receives the distribution may load the program into the main memory 902 and execute the above processing. The above program may be for realizing part of the functions described above, and may also be for realizing the above functions in combination with a program already recorded in the computer system.

[0030] As described above, several embodiments relating to this disclosure have been explained, but all of these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be carried out in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents.

[0031] <Note> The abnormality detection device, abnormality detection method, and program described in the embodiment can be understood, for example, as follows.

[0032] (1) The abnormality determination device according to the first embodiment comprises a command unit that outputs a control command value to a device to be controlled, an acquisition unit that acquires an operating status value of the device to be controlled, and an abnormality determination unit that determines an abnormality if the deviation between the control command value and the operating status value deviates by a predetermined threshold or more and continues for a predetermined waiting time or longer, wherein the abnormality determination unit determines the abnormality based on the deviation between the operating status value acquired at a certain time and the control command value that has been in the past for a predetermined delay time from that time. This makes it possible to shorten the waiting time.

[0033] (2) The abnormality determination device according to the second embodiment is the abnormality determination device of (1), wherein the abnormality determination unit delays the control command value output from the command unit by the delay time and calculates the deviation from the operating status value. This makes it possible to shorten the waiting time.

[0034] (3) The abnormality determination device according to the third embodiment is the abnormality determination device of (1) to (2), wherein the delay time is set to the time from when the control command value is determined or output until the controlled device starts operating based on the control command value. This makes it possible to shorten the waiting time.

[0035] (4) The abnormality determination device according to the fourth embodiment is the abnormality determination device according to (1) to (3), wherein the waiting time is set to the time from when the controlled device starts operating based on the control command value until it completes the operation. This makes it possible to set the minimum length of time necessary for abnormality determination in the waiting time and to avoid setting an unnecessarily long time in the waiting time.

[0036] (5) The abnormality determination device according to the fifth embodiment is the abnormality determination device according to (1) to (4), wherein the controlled device is a valve, the control command value is the valve opening command value, and the waiting time is set based on the time required for the valve to go from a fully closed state to a fully open state, or the time required for the valve to go from a fully open state to a fully closed state. This makes it possible to set the waiting time to the minimum length of time necessary for abnormality determination and to avoid setting an unnecessarily long time for the waiting time.

[0037] (6) The abnormality determination device according to the sixth embodiment is the abnormality determination device according to (1) to (5), wherein the controlled device is a valve, the control command value is an opening command value for the valve, the operating state value is the opening of the valve, and the waiting time is set based on the longer of the time required for the valve to fully open from the opening of the valve indicated by the operating state value, or the time required for the valve to fully close from the opening of the valve indicated by the operating state value. This makes it possible to set the waiting time to the minimum length of time necessary for abnormality determination and to avoid setting an unnecessarily long time for the waiting time.

[0038] (7) The abnormality determination device according to the seventh embodiment is the abnormality determination device according to (1) to (6), wherein the controlled device is a valve, the control command value is an opening command value for the valve, the operating state value is the opening of the valve, and the waiting time is set based on the time required for the valve opening indicated by the operating state value to change to the valve opening indicated by the control command value. This makes it possible to set the minimum length of time necessary for abnormality determination as the waiting time and to avoid setting an unnecessarily long time as the waiting time.

[0039] (8) An abnormality determination method according to the eighth aspect is an abnormality determination method performed by an abnormality determination device, comprising the steps of: outputting a control command value to a controlled device; acquiring an operating status value of the controlled device; and determining an abnormality if the deviation between the control command value and the operating status value deviates by a predetermined threshold or more for a predetermined waiting time or longer, wherein the abnormality determination is made based on the deviation between the operating status value acquired at a certain time and the control command value that has been in the past by a predetermined delay time from that time.

[0040] (9) The program according to the ninth aspect includes the steps of: outputting a control command value to a device to be controlled; acquiring an operating status value of the device to be controlled; and determining that an abnormality exists if the deviation between the control command value and the operating status value exceeds a predetermined threshold and continues for a predetermined waiting time or longer, wherein the step of determining an abnormality involves causing the computer to execute a process that determines the abnormality based on the deviation between the operating status value acquired at a certain time and the control command value that has been in the past for a predetermined delay time from that time.

[0041] According to the abnormality detection device, abnormality detection method, and program described above, in a technology that determines an abnormality when the state in which the opening degree command value and the actual opening degree deviate from each other continues for a certain waiting period or longer, the waiting period can be shortened.

[0042] 1, 2... System 3... Equipment V1, V2... Valve 10... Control device 11... Instruction unit 12... Monitoring unit 13... Anomaly detection unit 100... Equipment 900... Computer 901... CPU 902... Main memory 903... Auxiliary memory 904... Input / Output interface 905... Communication interface

Claims

1. An abnormality determination device comprising: a command unit that outputs a control command value to a device to be controlled; an acquisition unit that acquires an operating status value of the device to be controlled; and an abnormality determination unit that determines an abnormality if the deviation between the control command value and the operating status value exceeds a predetermined threshold and continues for a predetermined waiting time or longer, wherein the abnormality determination unit determines the abnormality based on the deviation between the operating status value acquired at a certain time and the control command value that has been in the past for a predetermined delay time from that time.

2. The abnormality determination device according to claim 1, wherein the abnormality determination unit delays the control command value output from the command unit by the delay time and calculates the deviation from the operating status value.

3. The abnormality determination device according to claim 1 or claim 2, wherein the delay time is set to the time from when the control command value is determined or output until the controlled device starts operating based on the control command value.

4. The waiting time is set to the time from when the controlled device starts operating based on the control command value until it completes the operation. The abnormality determination device according to claim 1 or claim 2.

5. The abnormality determination device according to claim 1 or 2, wherein the controlled device is a valve, the control command value is the valve opening command value, and the waiting time is set based on the time required for the valve to move from a fully closed state to a fully open state, or the time required for the valve to move from a fully open state to a fully closed state.

6. The abnormality determination device according to claim 1 or 2, wherein the controlled device is a valve, the control command value is an opening command value for the valve, the operating state value is the opening degree of the valve, and the waiting time is set based on the longer of the time required for the valve to fully open from the opening degree indicated by the operating state value, or the time required for the valve to fully close from the opening degree indicated by the operating state value.

7. The abnormality determination device according to claim 1 or 2, wherein the controlled device is a valve, the control command value is an opening command value for the valve, the operating state value is the opening degree of the valve, and the waiting time is set based on the time required for the valve opening degree indicated by the operating state value to change to the valve opening degree indicated by the control command value.

8. An abnormality determination method performed by an abnormality determination device, comprising: a step of outputting a control command value to a controlled device; a step of acquiring an operating status value of the controlled device; and a step of determining an abnormality if the deviation between the control command value and the operating status value deviates by a predetermined threshold or more for a predetermined waiting time or longer, wherein the abnormality determination step is performed based on the deviation between the operating status value acquired at a certain time and the control command value that was acquired at a predetermined delay time prior to that time.

9. A program that causes a computer to perform the following steps: output a control command value to a device to be controlled; acquire an operating status value of the device to be controlled; and determine that an abnormality exists if the deviation between the control command value and the operating status value exceeds a predetermined threshold and continues for a predetermined waiting time or longer, wherein the step of determining an abnormality involves performing a process to determine the abnormality based on the deviation between the operating status value acquired at a certain time and the control command value from a predetermined delay time prior to that time.

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