Anomaly monitoring system and anomaly monitoring method

Abstract

In a system that monitors abnormalities in temperature control devices, the pressure abnormalities of the temperature control devices can be easily monitored, and the abnormality is notified before it leads to an emergency shutdown. [Solution] The abnormality monitoring system 100 includes: a pressure estimation unit 21a that estimates the pressure of the refrigerant based on the output values ​​of sensors 10a and 10b installed on the suction side and / or discharge side of the refrigerant R in the compressor CM, which correspond to the temperature of the refrigerant R; a reference pressure setting unit 21b that sets a reference pressure Ps from among the history of the estimated pressure P during a predetermined period T1 while a reference operation is being performed in the temperature control device TM; and an abnormality notification instruction unit 21c that executes an instruction to notify of an abnormality based on a comparison between the estimated pressure P and the preset reference pressure Ps while an operation to be monitored is being performed in the temperature control device TM.

Description

Technical Field

[0001] The present invention relates to an abnormality monitoring system for monitoring abnormalities in a temperature control device including a compression refrigerator, and an abnormality monitoring method.

Background Art

[0002] Generally, temperature control devices such as chillers are provided in semiconductor manufacturing equipment such as etchers, CVD devices, and probers. In the temperature control device, the temperature can be adjusted by driving a compression refrigerator. A pressure detection sensor is usually provided in the refrigerant circuit of the compression refrigerator. When a pressure abnormality in the refrigerant piping circuit is detected by the pressure detection sensor, serious failures of the system are often avoided.

[0003] As this type of technology, the pressure abnormality detection means of Patent Document 1 below is known. In this pressure abnormality detection means, a high and low pressure switch for pressure detection is used. The discharge side pressure (high pressure) and the suction side pressure (low pressure) of the compressor in the compression refrigerator are respectively detected by the high and low pressure switch.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

[0005] According to the pressure abnormality detection means of Patent Document 1 above, when the pressure is abnormally high or low, the electrical control circuit is opened by the high and low pressure switch. Accordingly, the buzzer can sound to notify the user of the abnormality. However, in the technology of Patent Document 1 above, it can be said that there is much room for improvement in the following points.

[0006] In semiconductor manufacturing facilities, multiple devices work together as a production line. Therefore, if an emergency shutdown occurs in one device, all devices on the production line will be forcibly shut down. This can directly impact the product, resulting in defective products, reduced yield, chemical contamination, and missing parts. As a result, large-scale waste of entire batches may occur.

[0007] Furthermore, forced shutdowns can have an impact on equipment and production lines. For example, chamber contamination can occur due to vacuum breakdown caused by the shutdown of vacuum equipment, cracking and delamination due to thermal stress from temperature drops caused by the shutdown of high-temperature furnaces, and pipe blockage due to residues and precipitates from the shutdown of liquid chemicals and gas supply lines.

[0008] This can have a significant impact on production plans. For example, an unplanned downtime of a few hours can lead to delays of several days to several weeks. This raises concerns about contract breaches due to delivery delays and decreased utilization rates in subsequent processes due to bottlenecks caused by the downtime.

[0009] Furthermore, this can have a very significant impact on the restoration of equipment. This is because safety checks of the equipment require restoration checks of the power, gas, and chemical systems, leak checks for vacuum pumps and chambers, and stabilization of chillers. In addition, restarting the production line may require initialization and cleaning of each device by performing chamber cleaning and chemical replacement, readjustment of temperature, pressure, and flow rate, confirmation of process stabilization through prototyping and trial runs, re-evaluation of process variability, confirmation of statistical process control values, and reconstruction of traceability.

[0010] To address the aforementioned problems, it is conceivable to apply the pressure anomaly detection means described in Patent Document 1 to the temperature control device. In this case, high and low pressure switches and devices for detection would be specially installed on the existing equipment so that anomalies could be detected before an emergency shutdown. This would necessitate refrigerant recovery, modification of the refrigerant piping to add high and low pressure switches, and refrigerant refilling. Consequently, this would lead to increased costs, increased risks, and the termination of the manufacturer's warranty due to equipment modifications. Therefore, a system that can monitor and alarm for pressure anomalies without requiring modifications to the temperature control device is preferable.

[0011] In view of the above, the object of the present invention is to provide an abnormality monitoring system and an abnormality monitoring method that can easily monitor pressure abnormalities in a temperature control device and notify of abnormalities before they lead to an emergency shutdown. [Means for solving the problem]

[0012] The technical means of the present invention for solving this technical problem is characterized by the following: The abnormality monitoring system of the present invention is a system for monitoring abnormalities in a temperature control device including a compression type refrigerator in which a compressor is interposed in the refrigerant circuit. The abnormality monitoring system of the present invention comprises: a pressure estimation unit that estimates the pressure of the refrigerant based on the output values ​​of sensors installed on the suction side and / or discharge side of the refrigerant in the compressor, which correspond to the temperature of the refrigerant; a reference pressure setting unit that sets a reference pressure, which is a reference pressure, from the history of the estimated pressure over a predetermined period while a reference operation is being performed in the temperature control device; and an abnormality notification instruction unit that executes an instruction to notify of an abnormality based on a comparison between the estimated pressure and the preset reference pressure while the operation to be monitored is being performed in the temperature control device. The reference pressure setting unit sets the reference pressure to be the maximum value of the estimated pressure after the start of the predetermined period, with the temperature control device being started up, and when the temperature control device is performing an operation to be monitored, the abnormality notification instruction unit determines in a comparison that the estimated pressure has been lower than the reference pressure for a predetermined period, and further includes a pressure correction unit that obtains a corrected value that is lower than the estimated pressure obtained by correcting the pressure estimated by the pressure estimation unit, and when a corrected value is obtained by the pressure correction unit, the abnormality notification instruction unit uses the obtained corrected value instead of the estimated pressure itself when comparing with the reference pressure. .

[0015] In the abnormality monitoring system of the present invention, the abnormality notification instruction unit includes at least one means of notifying the abnormality, which is to display it on an indicator light, to output an alarm sound, and to send an email.

[0016] In the abnormality monitoring system of the present invention, the pressure estimation unit uses a sensor that is detachably installed on the outer surface of the refrigerant piping connected to the suction port of the compressor, and / or on the outer surface of the refrigerant piping connected to the discharge port. [Effects of the Invention]

[0018] According to the present invention, pressure abnormalities in temperature control devices can be easily monitored, and abnormalities can be notified before an emergency shutdown occurs. This makes it possible to know which equipment is experiencing an abnormality, and to transition the production line to a planned shutdown before an emergency shutdown occurs. This helps to minimize damage. Furthermore, upon receiving notification of an abnormality, a replacement temperature control device (e.g., chiller) can be prepared in advance, reducing time loss without stopping the production process. Moreover, it is easy to install and versatile, does not require dedicated ancillary equipment for individual temperature control devices, and monitoring of the prepared replacement device can be performed immediately. [Brief explanation of the drawing]

[0019] [Figure 1] This is an overall schematic diagram of an anomaly monitoring system according to an embodiment of the present invention. [Figure 2] This figure illustrates an example of how the sensor shown in Figure 1 is mounted. [Figure 3] Figure 1 is a functional block diagram of the abnormality monitoring device shown. [Figure 4] This is an example of a dataset corresponding to the relationship between refrigerant temperature and refrigerant pressure, created by the control unit shown in Figure 1. [Figure 5] This figure illustrates an example of setting the reference pressure in the control unit shown in Figure 1. [Figure 6] Figure 1 shows a flowchart illustrating the processing of the program executed by the control unit. [Modes for carrying out the invention]

[0020] Hereinafter, embodiments of the present invention will be described based on the drawings.

[0021] As shown in FIG. 1, an abnormality monitoring system 100 according to an embodiment of the present invention is applied to a temperature control device TM. The temperature control device TM is installed in, for example, a semiconductor manufacturing device or the like and can adjust the temperature. The abnormality monitoring system 100 is a system that monitors abnormalities of the temperature control device TM. The temperature control device TM includes a compression refrigerator RC, and a compressor CM is interposed in the refrigerant circuit of the compression refrigerator RC.

[0022] The abnormality monitoring system 100 includes a sensor 10a, a sensor 10b, and an abnormality monitoring device 20. The sensor 10a and the sensor 10b are installed on the suction side and the discharge side of the refrigerant in the compressor CM. More specifically, the sensor 10a and the sensor 10b are respectively detachably installed on the outer surface of the refrigerant pipe connected to the suction port of the compressor CM and the outer surface of the refrigerant pipe connected to the discharge port.

[0023] As shown in FIG. 2, in the present embodiment, the sensor 10a and the sensor 10b output values corresponding to the temperature of the refrigerant R. More specifically, the temperature of the refrigerant R inside the refrigerant pipe PI is acquired by the sensor 10a and the sensor 10b from the outer surface OS through the pipe PI. When installing the sensor 10a and the sensor 10b, they may be attached to the outer surface OS, and when detaching, the sensor 10a and the sensor 10b may be peeled off from the outer surface OS.

[0024] As shown in FIG. 1, the sensor 10a and the sensor 10b are communicably connected to the abnormality monitoring device 20. The communication format is wired in this embodiment, but it may be wireless instead. The output values of the sensor 10a and the sensor 10b are respectively sent toward the abnormality monitoring device 20.

[0025] In this embodiment, both sensors 10a and 10b are used, but instead, only one of sensors 10a and 10b may be used. That is, the sensor may be installed on only one of the refrigerant suction side or discharge side of the compressor CM.

[0026] The anomaly monitoring device 20 comprises a control unit 21, an input / output device 22, and an anomaly notification device 23. The control unit 21 receives the outputs of the aforementioned sensors 10a and 10b and performs various calculation processes. The control unit 21 is also electrically connected to the input / output device 22 and the anomaly notification device 23 via an interface.

[0027] The input / output device 22 may be, for example, a touch panel monitor. The input / output device 22 can receive activation instructions for the abnormality monitoring device 20 and input / setting parameters through operator operation. The input and set parameters are used in calculation processing by the control unit 21. The input / output device 22 may be configured to display the detected values ​​acquired and the data obtained from calculation processing by the control unit 21.

[0028] The abnormality notification device 23 may be, for example, an indicator light. The abnormality notification device 23 is capable of displaying an output corresponding to the calculation processing of the control unit 21. If the abnormality notification device 23 is an indicator light, it may be configured to change the color and display mode depending on the state. More specifically, for example, when the control unit 21 (abnormality notification instruction unit 21c) gives an instruction to notify of an abnormality, the abnormality notification device 23 may display a red flashing light. On the other hand, under normal circumstances, the abnormality notification device 23 may display a green solid light.

[0029] In this embodiment, the abnormality notification device 23 is an indicator light, but it may be replaced with a speaker that outputs an alarm sound, an email sending terminal, etc. That is, when the control unit 21 (abnormality notification instruction unit 21c) gives an instruction to notify of an abnormality, the notification of the abnormality may be made by outputting an alarm sound or sending an email. If a speaker that outputs an alarm sound is used, a switch 24 for turning off the warning sound may be used. This switch 24 can be operated by the operator when the alarm sound is being output.

[0030] As shown in Figure 3, the control unit 21 includes a pressure estimation unit 21a, a reference pressure setting unit 21b, an abnormality notification instruction unit 21c, and a pressure correction unit 21d. The pressure estimation unit 21a, reference pressure setting unit 21b, abnormality notification instruction unit 21c, and pressure correction unit 21d of the control unit 21 are each composed of electrical / electronic circuits, a CPU, memory, stored programs, etc.

[0031] The pressure estimation unit 21a estimates the refrigerant pressure based on the output values ​​of sensors 10a and 10b corresponding to the refrigerant temperature. Pressure estimation may be performed, for example, by pre-defining the relationship between the refrigerant pressure and temperature for each temperature control device TM, and using this relationship and the output values ​​of sensors 10a and 10b. The output values ​​of sensors 10a and 10b are converted using AD conversion and used in the estimation process. For the relationship between the refrigerant pressure and temperature, depending on the type of refrigerant, a publicly available and known PT diagram may be used. On the other hand, if a refrigerant for which the PT diagram is not known is used, the refrigerant pressure and temperature may be actually obtained, and the relationship may be created using a program described later. In this way, by actually obtaining the pressure and temperature, the relationship between the refrigerant pressure and temperature can be created even when a mixed refrigerant (i.e., a refrigerant for which the PT diagram is not known) is used in the compression chiller RC. Therefore, regardless of whether the PT diagram is known or not for the type of refrigerant, the pressure estimation unit 21a can estimate the pressure with high accuracy.

[0032] As for the relationship between refrigerant pressure and refrigerant temperature, for example, a function (a so-called PT diagram) that uniquely determines the saturation pressure of the refrigerant depending on the refrigerant temperature may be used. This function may be appropriately selected from those defined for each type of refrigerant, and the dataset of the selected function may be stored in memory and used for pressure estimation.

[0033] Furthermore, the relationship between the refrigerant pressure and temperature may be one obtained by actually acquiring the refrigerant pressure and temperature. More specifically, the temperature control device TM may be operated steadily without any abnormalities, and the temperature and corresponding pressure may be acquired. The relationship may be created using the acquired temperature and pressure through calculation processing by the program described below. This program is stored in the memory of the control unit 21. The calculation processing is executed according to the operation of the input / output device 22. Sensors 10a and 10b may be used to acquire the refrigerant temperature, and a pressure indicator installed on the compression chiller may be used to acquire the pressure.

[0034] JPEG0007835486000002.jpg177131

[0035] The implementation process in the control unit 21 may be performed, for example, using the following function block pattern. Multipoint least squares We sequentially add 3 to 8 points while retaining only the mean and variance, and then calculate a linear regression (least squares). Regression equation (Example for low pressure. The same method applies to high pressure.) JPEG0007835486000003.jpg172120JPEG0007835486000004.jpg74121

[0036] When monitoring multiple temperature control devices TM individually, it is preferable to create a relationship between the refrigerant pressure and the refrigerant temperature for each temperature control device TM. In this case, the above-described program may be implemented in parallel to support multiple temperature control devices TM. The program may also be executed for the target temperature control device TM by operating the input / output device 22.

[0037] Figure 4 shows an example of a dataset illustrating the relationship between refrigerant pressure and temperature for R32, R410A, and R404A refrigerants. By using the program described above, the relationship between refrigerant pressure and temperature is created for each of the three temperature control devices TM that use each refrigerant. This dataset corresponding to the relationship between refrigerant pressure and temperature is stored in memory and made available to the pressure estimation unit 21a when estimating the pressure.

[0038] As shown in Figure 3, the reference pressure setting unit 21b pre-sets a reference pressure Ps, which is the reference pressure. This reference pressure Ps is used for determining abnormalities, as described later. When the reference pressure setting unit 21b sets the reference pressure Ps, the temperature control device TM performs a reference operation. It is preferable that this reference operation is performed after eliminating factors that could cause abnormalities in the temperature control device TM. While the reference operation is being performed, the pressure estimation unit 21a estimates the pressure.

[0039] As shown in Figure 5, pressure estimation is performed in the temperature control device TM during a predetermined period T1 while the standard operation is running. Then, the standard pressure Ps is set from the course of the estimated pressure P. The course of the estimated pressure P often follows the following pattern: When the temperature control device TM is operating normally, the estimated pressure P tends to gradually decrease over time from the time of startup ta. Then, after the time of transition to a stable state tb when the operation transitions to a stable state, the estimated pressure P remains at a low value.

[0040] Based on the above findings, the reference pressure setting unit 21b sets the reference pressure Ps to be the maximum value Pm of the estimated pressure P estimated from the time of startup ta onward. In this case, it is preferable that the starting point of the predetermined period T1 is set to the time of startup ta, and the ending point of the predetermined period T1 is set to the time of transition to the stable state tb. Thus, the reference pressure setting unit 21b sets the maximum value Pm of the estimated pressure P during the predetermined period T1 as the reference pressure Ps.

[0041] The reference pressure Ps (i.e., the "maximum value Pm" mentioned above) set by the reference pressure setting unit 21b is stored in memory and made available for use when the abnormality notification instruction unit 21c performs abnormality detection. The reference pressure Ps is set by the reference pressure setting unit 21b in advance before the temperature control device TM performs abnormality monitoring.

[0042] As shown in Figure 3, the abnormality notification instruction unit 21c executes an instruction to notify of an abnormality. This instruction is executed to the abnormality notification device 23 when it is determined that there is an abnormality in the temperature control device TM. The system is configured to determine whether or not there is an abnormality in the temperature control device TM when the operation to be monitored is being performed in the temperature control device TM.

[0043] Anomaly detection is performed based on a comparison between the estimated pressure P and the reference pressure Ps. Here, the estimated pressure P used for anomaly detection is the estimated pressure P estimated by the pressure estimation unit 21a when the operation to be monitored is being performed in the temperature control device. The reference pressure Ps used for anomaly detection is the reference pressure Ps preset by the reference pressure setting unit 21b, as described above.

[0044] As an example of determining an abnormality, the pressure is estimated at arbitrary fixed intervals, and when the estimated pressure P continuously exceeds the reference pressure Ps, the abnormality notification unit 21c signals It may be determined to be abnormal. On the other hand, if the estimated pressure P does not exceed the reference pressure Ps, it is determined not to be abnormal, and no instruction to notify of an abnormality is taken.

[0045] In particular, if it is determined that there is no abnormality, and the estimated pressure P remains below a reference pressure Ps for a predetermined period, it is preferable to correct the estimated pressure P used in the next determination. As an example of the correction, the estimated pressure P obtained by the pressure estimation unit 21a may be corrected downward.

[0046] This is because it is preferable to update the value used to determine abnormalities from the initial estimated pressure P to a corrected value so that it can track minute refrigerant leaks that do not immediately disrupt operation in the temperature control device TM, as well as fluctuations in pressure values ​​due to changes over time. This ensures stable monitoring.

[0047] As shown in Figure 3, based on the above findings, the control unit 21 is further equipped with a pressure correction unit 21d. When the operation to be monitored is being performed in the temperature control device TM, the pressure correction unit 21d acquires a corrected value Pc if, in the comparison by the abnormality notification instruction unit 21c, it is determined that the estimated pressure P has been at a value smaller than the reference pressure Ps for a predetermined period T2.

[0048] Here, the corrected value Pc is a value obtained by correcting the pressure (estimated pressure P) estimated by the pressure estimation unit 21a, and is a value smaller than the estimated pressure P. Furthermore, the predetermined period T2 for obtaining the corrected value Pc may be different from the predetermined period T1 (see Figure 5) described above.

[0049] Thus, when a corrected value Pc is obtained by the pressure correction unit 21d, the abnormality notification instruction unit 21c uses the obtained corrected value Pc instead of the estimated pressure P itself when comparing it with the reference pressure Ps. If the corrected value Pc continues to exceed the reference pressure Ps, the abnormality notification instruction unit 21c may determine that there is an abnormality. On the other hand, if the corrected value Pc does not exceed the reference pressure Ps, it is determined that there is no abnormality, and no instruction to notify of an abnormality is executed.

[0050] The actual operation of the abnormality monitoring system 100 will be explained with reference to the flowchart shown in Figure 6. The program in the abnormality monitoring system 100 causes the abnormality monitoring device 20 (computer) to execute the series of processes shown in Figure 6, thereby monitoring for abnormalities in the temperature control device TM. Note that the program for these processes may be stored in a storage medium, and this storage medium may be installed in the abnormality monitoring device 20.

[0051] When performing abnormality monitoring of the temperature control device TM, the process can be broadly divided into two parts. The first is the process of setting the reference pressure Ps. This process corresponds to the series of steps S1 to S3 in the flowchart of Figure 6. The second is the process of monitoring for abnormalities and, if an abnormality is determined, executing an instruction to notify the abnormality. This process corresponds to the series of steps S4 to S11 in the flowchart of Figure 6.

[0052] First, starting from step S1, the "relationship between refrigerant pressure and refrigerant temperature" in the temperature control device TM is created. To create this "relationship between refrigerant pressure and refrigerant temperature," the temperature and corresponding pressure are acquired while the temperature control device TM is operated steadily without any abnormalities. Sensors 10a and 10b are used to acquire the refrigerant temperature, and a pressure indicator installed in the compression chiller RC is used to acquire the pressure. The created "relationship between refrigerant pressure and refrigerant temperature" is stored in memory.

[0053] Next, in step S2, a reference operation is performed in the temperature control device TM. This operation is performed to set the reference pressure Ps.

[0054] Next, in step S3, the reference pressure Ps is set and stored based on the history of the estimated pressure P obtained from the "relationship between refrigerant pressure and refrigerant temperature" created in step S1. With the reference operation in progress, the output values ​​(i.e., refrigerant temperature) of sensors 10a and 10b are acquired. Based on the acquired output values, the estimated pressure P is searched for and determined from the "relationship between refrigerant pressure and refrigerant temperature".

[0055] Then, the progression of the estimated pressure P over time is drawn. From this progression of the estimated pressure P, the maximum value Pm during a predetermined period T1 is picked, and the reference pressure Ps is set to this maximum value Pm (see Figure 5). The set reference pressure Ps is stored in memory. Here, the estimation of the estimated pressure P is performed by the pressure estimation unit 21a, and the setting of the reference pressure Ps is performed by the reference pressure setting unit 21b.

[0056] Next, in step S4, the temperature control device TM performs the operation to be monitored. This operation is performed to monitor for abnormalities in the temperature control device TM.

[0057] Next, in step S5, the current estimated pressure P is estimated from the "relationship between refrigerant pressure and refrigerant temperature" created in step S1. The output values ​​(i.e., refrigerant temperature) of sensors 10a and 10b are acquired while the operation to be monitored is being performed. Based on the acquired output values, the estimated pressure P is searched and determined from the "relationship between refrigerant pressure and refrigerant temperature". Here, the estimation of the estimated pressure P is performed by the pressure estimation unit 21a.

[0058] Next, in step S6, it is determined whether or not the corrected pressure value Pc has been obtained. At this point, the corrected value Pc has not been obtained, so it is determined to be "No" and the process proceeds to the following step S7.

[0059] In step S7, it is determined whether the estimated pressure P from step S5 is greater than the reference pressure Ps from step S3. If the estimated pressure P is greater than the reference pressure Ps, the result is "Yes," and the process proceeds to step S8.

[0060] In step S8, an instruction is given to the anomaly notification device 23 to notify it of the anomaly. Upon receiving the instruction, the anomaly notification device 23 operates to notify it of the anomaly. Once step S8 is executed, the entire process is temporarily terminated.

[0061] On the other hand, if in step S7 the estimated pressure P is not greater than the reference pressure Ps, it is determined to be "No" and the process proceeds to the following step S9.

[0062] In step S9, it is determined whether the estimated pressure P remained lower than the reference pressure Ps for a predetermined period T2. If this condition is not met, the result is "No," and the process returns to step S5. On the other hand, if this condition is met, the result is "Yes," and the process proceeds to the following step S10.

[0063] In step S10, a corrected value Pc is obtained that is smaller than the estimated pressure P estimated by the pressure estimation unit 21a. The determination in step S9 and the acquisition of the corrected value Pc in step S10 are performed by the pressure correction unit 21d. Then, the process returns to step S5.

[0064] After step S5, step S6 determines whether or not the corrected pressure value Pc has been obtained. At this point, the corrected value Pc has been obtained in step S10, so the result is "Yes," and the process proceeds to step S11.

[0065] In step S11, it is determined whether the corrected value Pc from step S10 is greater than the reference pressure Ps from step S3. In other words, in this case, the corrected value Pc is used instead of the estimated pressure P when determining whether an anomaly is present.

[0066] In step S11, if the corrected value Pc is greater than the reference pressure Ps, it is determined to be "Yes" and the process proceeds to the following step S8. On the other hand, in step S11, if the corrected value Pc is not greater than the reference pressure Ps, it is determined to be "No" and the process returns to step S5 described above. Here, the determinations in steps S6, S7, and S11 described above, and the instruction to notify of an abnormality in step S8, are executed by the abnormality notification instruction unit 21c.

[0067] As described above, the abnormality monitoring system 100 according to the embodiment of the present invention has the following effects. The abnormality monitoring system 100 of this embodiment is a system for monitoring abnormalities in a temperature control device TM including a compression type refrigerator RC in which a compressor CM is interposed in the refrigerant circuit. The abnormality monitoring system 100 includes a pressure estimation unit 21a that estimates the pressure of the refrigerant based on the output values ​​of sensors 10a and 10b installed on the suction side and / or discharge side of the refrigerant R in the compressor CM, which correspond to the temperature of the refrigerant R; a reference pressure setting unit 21b that, during a predetermined period T1 in which a reference operation is being performed in the temperature control device TM, sets a reference pressure Ps from among the estimated pressure P history; and an abnormality notification instruction unit 21c that, when the operation to be monitored is being performed in the temperature control device TM, executes an instruction to notify of an abnormality based on a comparison between the estimated pressure P and the preset reference pressure Ps.

[0068] This allows for easy monitoring of pressure abnormalities in temperature control devices TM, enabling notification of abnormalities before an emergency shutdown occurs. Therefore, it is possible to know which equipment is experiencing an abnormality, and the production line can be transitioned to a planned shutdown before an emergency shutdown occurs. This helps to minimize damage. Furthermore, upon notification of an abnormality, a replacement temperature control device TM (e.g., chiller) can be prepared in advance, reducing time loss without stopping the production process. Moreover, it is easy to install and versatile, does not require dedicated ancillary equipment for individual temperature control devices TM, and monitoring of prepared replacement units can be performed immediately.

[0069] In the abnormality monitoring system 100 according to an embodiment of the present invention, the reference pressure setting unit 21b sets the starting point of the predetermined period T1 to the startup time ta of the temperature control device, and the reference pressure Ps to become the maximum value Pm of the estimated pressure P after the startup time ta.

[0070] The estimated pressure P tends to gradually decrease over time from startup ta when the temperature control device TM is operating normally. Then, after the transition to a stable state tb, when the operation moves to a stable state, the estimated pressure P remains at a low value. With the above configuration, the reference pressure Ps can be set appropriately, reflecting this progression of the estimated pressure P.

[0071] An abnormality monitoring system 100 according to an embodiment of the present invention further includes a pressure correction unit 21d that, when the temperature control device TM is performing an operation to be monitored, and the abnormality notification instruction unit 21c determines that the estimated pressure P has been reduced to a value smaller than the reference pressure Ps for a predetermined period T2, the estimated pressure P estimated by the pressure estimation unit 21a is corrected to obtain a corrected value Pc that is smaller than the estimated pressure P, and when the abnormality notification instruction unit 21c obtains a corrected value Pc by the pressure correction unit 21d, it uses the obtained corrected value Pc instead of the estimated pressure P itself when comparing it with the reference pressure Ps.

[0072] According to this, the value used to determine abnormalities is updated from the initial estimated pressure P to a smaller corrected value Pc. Therefore, the temperature control device TM can track even minute refrigerant leaks that do not immediately disrupt operation, as well as fluctuations in pressure values ​​due to changes over time. Consequently, stable monitoring can be performed.

[0073] In the abnormality monitoring system 100 according to an embodiment of the present invention, the abnormality notification instruction unit 21c includes at least one means of notifying the abnormality, from displaying with an indicator light, outputting an alarm sound, and sending an email.

[0074] According to this, the abnormality notification device 23 can notify of abnormalities in a format suitable for the situation at the site.

[0075] In the abnormality monitoring system 100 according to an embodiment of the present invention, the pressure estimation unit 21a uses sensors detachably installed on the outer surface OS of the refrigerant piping PI connected to the suction port of the compressor CM, and / or on the outer surface OS of the refrigerant piping PI connected to the discharge port, as the sensors 10a and 10b.

[0076] According to this, the compression chiller RC of the temperature control device TM does not need to be modified for sensor installation, and sensors 10a and 10b can be easily installed. Furthermore, when removing sensors 10a and 10b from the compression chiller RC, they can be easily removed without affecting the compression chiller RC. [Explanation of Symbols]

[0077] 10a, 10b... Sensors, 20... Anomaly monitoring device, 21... Control unit, 21a... Pressure estimation unit, 21b... Reference pressure setting unit, 21c... Anomaly notification instruction unit, 21d... Pressure correction unit, 23... Anomaly notification device, 100... Anomaly monitoring system, CM... Compressor, R... Refrigerant, RC... Compression type refrigerator, TM... Temperature control device

Claims

1. In an abnormality monitoring system that monitors abnormalities in a temperature control device including a compression type refrigerator with a compressor interposed in the refrigerant circuit, A pressure estimation unit estimates the pressure of the refrigerant based on the output values ​​of sensors installed on the suction side and / or discharge side of the compressor, which correspond to the temperature of the refrigerant. The temperature control device includes a reference pressure setting unit that, during a predetermined period while the standard operation is being performed, sets a reference pressure, which is the standard pressure, from the estimated pressure history. An abnormality notification instruction unit, which, when the operation to be monitored is being performed in the temperature control device, executes an instruction to notify of an abnormality based on a comparison between the estimated pressure and the preset reference pressure, Equipped with, The aforementioned reference pressure setting unit is The starting point of the predetermined period is the time when the temperature control device is started, and the reference pressure is set to be the maximum value of the estimated pressure after the time of startup. When the temperature control device is performing an operation to be monitored, and the abnormality notification instruction unit determines, through comparison, that the estimated pressure has fallen to a value smaller than the reference pressure for a predetermined period of time, the pressure correction unit acquires a value obtained by correcting the pressure estimated by the pressure estimation unit, which is a corrected value smaller than the estimated pressure. Furthermore, The aforementioned abnormality notification instruction unit, When a corrected value is obtained by the pressure correction unit, the obtained corrected value is used instead of the estimated pressure itself when comparing it with the reference pressure. Anomaly monitoring system.

2. In the abnormality monitoring system according to claim 1, The aforementioned abnormality notification instruction unit, The notification of the aforementioned abnormality includes at least one means of displaying it on an indicator light, outputting an alarm sound, and sending an email. Anomaly monitoring system.

3. In the abnormality monitoring system according to Claim 1 or Claim 2, The pressure estimation unit, The aforementioned sensor is a sensor that is detachably installed on the outer surface of the refrigerant piping connected to the compressor's intake port and / or on the outer surface of the refrigerant piping connected to the compressor's discharge port. Anomaly monitoring system.

Images