Thermal storage unit status monitoring system

Abstract

To monitor the status of a heat storage unit disposed in a return circuit that returns a heat medium from a controlled object to a chiller device, and to detect deterioration of the heat storage unit in advance.SOLUTION: A monitoring system 30 is used for a heat exchange system 1 in which a low-temperature heat storage unit 4A is disposed in a low-temperature fluid return circuit L62 that returns a temperature control fluid from a temperature control member 110 to a low-temperature chiller device 120A, and a high-temperature heat storage unit 4B is disposed in a high-temperature fluid return circuit L72 that returns the temperature control fluid from the temperature control member 110 to a high-temperature chiller device 120B. The monitoring system 30 uses a low-temperature inflow temperature sensor 32, a low-temperature outflow temperature sensor 33, a high-temperature inflow temperature sensor 34, and a high-temperature outflow temperature sensor 35 to measure fluid temperature of the temperature control fluid flowing through a low-temperature heat storage unit 4A and a high-temperature heat storage unit 4B, and determines the status of the low-temperature heat storage unit 4A and the high-temperature heat storage unit 4B based on the temperature change.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a thermal storage unit state monitoring system. [Background technology]

[0002] For example, a semiconductor manufacturing system adjusts the temperature of the wafer to a uniform temperature for etching by circulating a temperature control fluid between a temperature control member on which the wafer is placed and a chiller device that stores the temperature control fluid at a predetermined temperature. If the temperature control fluid that has exchanged heat with the temperature control member is returned directly to the chiller device, the load on the chiller device increases because of the large temperature difference between the temperature control fluid returned to the chiller device and the temperature control fluid stored in the chiller device.

[0003] Therefore, the heat exchange system of Patent Document 1 has a heat storage unit disposed in the return circuit that returns the temperature control fluid from the temperature control member to the chiller device. The heat storage unit exchanges heat with the temperature control fluid returned to the chiller device, thereby reducing the temperature difference between the temperature control fluid returned to the chiller device and the temperature control fluid stored in the chiller device. This reduces the load on the chiller device. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2020 / 217800 Summary of the Invention [Problem to be solved by the invention]

[0005] The heat storage unit includes a heat exchange flow path through which a temperature control fluid flows, fins that exchange heat with the temperature control fluid, etc. For example, when deposits adhere to the heat exchange flow path or fins due to deterioration of the temperature control fluid, the heat exchange efficiency of the heat storage unit decreases. Conventionally, there has been no system that monitors the state of the heat storage unit and detects deterioration of the heat storage unit in advance. [Means for solving the problem]

[0006] One aspect of the technology disclosed in this specification is (1) used in a heat exchange system including a return circuit that returns a heat medium circulating between a controlled object and a chiller to the chiller, and a heat storage unit arranged in the return circuit and exchanging heat with the heat medium, and is configured to have a temperature sensor that measures a fluid temperature of the heat medium circulating through the heat storage unit, and a status monitoring unit that uses the temperature sensor to measure a change in temperature of the heat medium circulating through the heat storage unit when the heat exchange system executes a process of changing the temperature of the heat medium circulating through the controlled object and determines the status of the heat storage unit based on the temperature change.

[0007] The heat storage unit status monitoring system having the above configuration measures the temperature change of the heat medium circulating through the heat storage unit when the heat exchange system executes a process, and judges the status of the heat storage unit based on the temperature change. Thus, the heat storage unit status monitoring system monitors the status of the heat storage unit arranged in the return circuit that returns the heat medium from the controlled object to the chiller device, and can detect deterioration of the heat storage unit in advance.

[0008] (2) In the heat storage unit status monitoring system described in (1), it is preferable that the status monitoring unit executes a comparison data acquisition process to acquire comparison data based on a first fluid temperature measured by the temperature sensor at a first timing when the heat exchange system executes specific process conditions, an evaluation data acquisition process to acquire evaluation data corresponding to the comparison data based on a second fluid temperature measured by the temperature sensor at a second timing after executing the comparison data acquisition process when the heat exchange system executes the specific process conditions, and a judgment process to judge the status of the heat storage unit based on the comparison data and the evaluation data.

[0009] The heat storage unit status monitoring system having the above configuration determines the status of the heat storage unit by comparing comparison data based on the fluid temperature actually measured when the heat exchange system is operated to execute a process under the same process conditions with the evaluation data, thereby enabling the status of the heat storage unit to be determined with high accuracy.

[0010] (3) In the heat storage unit state monitoring system described in (2), the temperature sensor is a first temperature sensor that measures an inflow temperature, which is the temperature of the heat medium flowing into the heat storage unit, and a second temperature sensor that measures an outflow temperature, which is the temperature of the heat medium flowing out of the heat storage unit, and the comparison data is a first heat exchange amount calculated from a difference between a first inflow peak value, which is the peak value of the inflow temperature measured by the first temperature sensor, and a first outflow peak value, which is the peak value of the outflow temperature measured by the second temperature sensor, and the evaluation The data is a second heat exchange amount calculated from the difference between a second inflow peak value, which is the peak value of the inflow temperature measured by the first temperature sensor, and a second outflow peak value, which is the peak value of the outflow temperature measured by the second temperature sensor, and the determination process preferably calculates a heat exchange differential value, which is the difference between the first heat exchange amount and the second heat exchange amount, and if the heat exchange differential value is greater than or equal to a differential threshold, determines that the heat storage unit is not degraded, and if the heat exchange differential value is not greater than or equal to the differential threshold, determines that the heat storage unit is degraded.

[0011] The heat storage unit status monitoring system having the above configuration calculates the first heat exchange amount and the second heat exchange amount based on the actual measured values ​​of the inflow temperature and outflow temperature, and compares the difference between them, that is, the heat exchange amount difference value, with a difference threshold value to determine deterioration of the heat storage unit, thereby making it possible to accurately determine deterioration of the heat storage unit.

[0012] (4) In the heat storage unit status monitoring system described in (2), it is preferable that the temperature sensor measures an outflow temperature, which is the temperature of the heat medium flowing out of the heat storage unit, the comparison data is a first peak value, which is the peak value of the outflow temperature measured by the temperature sensor, and the evaluation data is a second peak value, which is the peak value of the outflow temperature measured by the temperature sensor, and the judgment process calculates a peak difference value, which is the difference between the first peak value and the second peak value, and if the peak difference value is equal to or less than a peak threshold, judges that the heat storage unit is not degraded, and if the peak difference value is not equal to or less than the peak threshold, judges that the heat storage unit is degraded.

[0013] The heat storage unit status monitoring system having the above configuration determines the deterioration of the heat storage unit using the first peak value and the second peak value based on the actual measurement value of the outflow temperature, so that the deterioration of the heat storage unit can be determined accurately and simply.

[0014] (5) In the heat storage unit status monitoring system described in any one of (2) to (4), it is preferable that the temperature sensor includes an inflow temperature sensor that measures an inflow temperature, which is the temperature of the heat medium flowing into the heat storage unit, and the status monitoring unit acquires a first inflow temperature measured by the inflow temperature sensor when executing the comparison data acquisition process, acquires a second inflow temperature measured by the inflow temperature sensor when executing the evaluation data acquisition process, and before executing the judgment process, executes a pre-determination process to determine whether an inflow temperature peak difference value, which is the difference between a first inflow temperature peak value that is the peak value of the first inflow temperature and a second inflow temperature peak value that is the peak value of the second inflow temperature, is equal to or greater than an inflow difference threshold, and does not execute the judgment process if it is determined in the pre-determination process that the inflow temperature peak difference value is equal to or greater than the inflow difference threshold, and executes the judgment process if it is determined in the pre-determination process that the inflow temperature peak difference value is not equal to or greater than the inflow difference threshold.

[0015] The temperature of the heat medium flowing into the heat storage unit may change due to an abnormality occurring outside the heat storage unit. The heat exchange amount of the heat storage unit varies depending on the temperature of the heat medium flowing into the heat storage unit. Therefore, when an abnormality occurs outside the heat storage unit, the accuracy of the judgment decreases even if the state of the heat storage unit is judged. Therefore, the heat storage unit state monitoring system having the above configuration does not perform the judgment process when the inflow temperature peak value, which is the difference between the peak value of the inflow temperature acquired when the comparison data acquisition process is executed and the peak value of the inflow temperature acquired when the evaluation data acquisition process is executed, is equal to or greater than the inflow difference threshold value, that is, when the temperature of the heat medium flowing into the heat storage unit abnormally fluctuates, since there is a high possibility that an abnormality exists outside the heat storage unit. This makes it possible to avoid unnecessary judgment processes being performed in a situation where the accuracy of the judgment decreases.

[0016] (6) In the heat storage unit status monitoring system described in any one of (1) to (5), it is preferable that the temperature sensor measures an outflow temperature, which is the temperature of the heat medium flowing out of the heat storage unit, and the status monitoring unit calculates a first rate of change at which the outflow temperature measured by the temperature sensor changes from a steady temperature during a first process, calculates a second rate of change at which the outflow temperature measured by the temperature sensor changes from a steady temperature during a second process executed immediately after the first process, and determines that the heat storage unit is degraded when the second rate of change deviates from the first rate of change by more than a predetermined range.

[0017] The heat storage unit status monitoring system having the above configuration determines a first rate of change based on the actual measured value of the outflow temperature when a first process is executed. The heat storage unit status monitoring system determines a second rate of change based on the actual measured value of the outflow temperature when a second process is executed under the same process conditions as the first process immediately after the first process. The heat storage unit status monitoring system determines that the heat storage unit has deteriorated when the second rate of change deviates from the first rate of change by more than a predetermined range. In this way, the heat storage unit status monitoring system can quickly detect an abnormality in the heat storage unit when, for example, the heat storage unit breaks down due to an abnormal temperature.

[0018] (7) In the heat storage unit status monitoring system described in (1), it is preferable that the temperature sensors are a first temperature sensor that measures an inflow temperature, which is the temperature of the heat medium flowing into the heat storage unit, and a second temperature sensor that measures an outflow temperature, which is the temperature of the heat medium flowing out from the heat storage unit, and when changing the temperature of the heat medium circulating through the controlled object, the status monitoring unit performs a measurement process that measures the inflow temperature using the first temperature sensor and further measures the outflow temperature using the second temperature sensor, an estimation process that estimates an outflow temperature estimate of the heat medium flowing out from the heat storage unit based on the inflow temperature measured in the measurement process, and a judgment process that compares the outflow temperature estimate estimated in the estimation process with the outflow temperature measured in the measurement process to judge the status of the heat storage unit.

[0019] The heat storage unit status monitoring system having the above configuration measures the inflow temperature of the heat medium flowing into the heat storage unit and the outflow temperature of the heat medium flowing out of the heat storage unit when the heat exchange system executes a process. The heat storage unit status monitoring system estimates the normal outflow temperature from the measured inflow temperature. The heat storage unit status monitoring system compares the estimated value of the outflow temperature with the actual measured value to determine the state of the heat storage unit. This makes it possible to determine the state of the heat storage unit when the heat exchange system executes a process even if comparison data has not been obtained in advance, thereby increasing versatility. In addition, it is expected that the state of the heat storage unit can be determined even if the set temperature of the heat medium circulated to the controlled object is changed for each process.

[0020] (8) In the heat storage unit status monitoring system described in any one of (1) to (7), it is preferable that the system has a communication unit connected to a host controller that controls a host system, and the status monitoring unit monitors the temperature change of the heat medium and determines deterioration of the heat storage unit in response to an instruction from the host controller.

[0021] The heat storage unit state monitoring system having the above configuration reduces the burden of managing the timing of measuring the fluid temperature and judging the state of the heat storage unit.

[0022] (9) In the heat storage unit status monitoring system described in any one of (1) to (7), it is preferable that the status monitoring unit monitors the temperature change of the heat medium and determines deterioration of the heat storage unit when the fluid temperature measured by the temperature sensor changes from a steady state by a specified temperature or more.

[0023] The heat storage unit status monitoring system having the above configuration measures the fluid temperature and determines the status of the heat storage unit when the fluid temperature changes from a steady state by more than a specified temperature, so that the heat storage unit status monitoring system can determine the status of the heat storage unit by itself without communicating with an external device.

[0024] (10) In the heat storage unit status monitoring system described in any one of (1) to (7), it is preferable that the system has a communication unit communicatively connected to a host controller that controls a host system, the host controller transmits a process recipe including process conditions for controlling the temperature of the heat medium circulating through the controlled object, and the status monitoring unit receives the process recipe using the communication unit, and monitors the temperature change of the heat medium and determines deterioration of the heat storage unit according to the process conditions included in the received process recipe.

[0025] The heat storage unit status monitoring system having the above configuration measures the fluid temperature and determines the status of the heat storage unit based on the process recipe received from the upper controller, so that the heat storage unit status monitoring system itself can determine the status of the heat storage unit while reducing the number of communications with the upper controller.

[0026] (11) In the heat storage unit status monitoring system described in any one of (2) to (5), it is preferable that the status monitoring unit is configured to execute a mode switching process, and the mode switching process is configured to switch to a test mode in which the comparison data acquisition process is executed when the comparison data has not been acquired or when the acquired comparison data is to be changed, and to switch to a monitoring mode in which the evaluation data acquisition process and the judgment process are executed when the comparison data has been acquired and the acquired comparison data is not to be changed.

[0027] According to the thermal storage unit state monitoring system having the above configuration, for example, when the process recipe is changed, the comparison data can be acquired again, and the state of the thermal storage unit can be determined with high accuracy.

[0028] (12) In the heat storage unit status monitoring system described in any one of (1) to (11), it is preferable that the system has a communication unit that is communicatively connected to a host controller that controls a host system that executes a process using the controlled object, and the status monitoring unit executes a notification process to notify the host controller of temperature data based on the fluid temperature measured by the temperature sensor using the communication unit, and the host controller determines whether or not there is an abnormality in the host system based on the temperature data.

[0029] According to the heat storage unit status monitoring system having the above configuration, for example, when the heat storage unit is in a normal state and the heat medium circulating through the controlled object is not controlled to a set temperature, the upper controller can detect an abnormality in the upper system. Effect of the Invention

[0030] According to the above configuration, the state of the heat storage unit disposed in the return circuit that returns the heat medium from the controlled object to the chiller device can be monitored, making it possible to detect deterioration of the heat storage unit in advance. [Brief description of the drawings]

[0031] [Figure 1] FIG. 2 is a diagram illustrating a circuit of a heat exchange system using the heat storage unit state monitoring system of the first embodiment. [Diagram 2] FIG. 2 is a diagram illustrating a circuit of a heat exchange system. [Diagram 3] FIG. 2 is a diagram illustrating a circuit of a heat exchange system. [Figure 4] FIG. 2 is a diagram showing an electrical configuration of the heat storage unit state monitoring system. [Diagram 5] FIG. 11 is a diagram showing an example of a change in fluid temperature in response to a change in the circulation circuit set temperature. [Figure 6] FIG. 11 is a sequence diagram illustrating a state monitoring operation. [Figure 7] 11 is a flowchart illustrating an example of a procedure of a comparison data acquisition process. [Figure 8] This is a graph showing the temperature change on the high temperature side extracted from FIG. [Figure 9] This is a graph showing the temperature change on the low temperature side extracted from FIG. [Figure 10] 11 is a flowchart illustrating an example of a procedure of an evaluation data acquisition process. [Figure 11] 10 is a flowchart illustrating an example of a procedure for a deterioration determination process. [Figure 12] 10 is a flowchart showing an example of a procedure of a comparison data acquisition process executed by a heat storage unit monitoring system in a second embodiment. [Figure 13] 11 is a flowchart illustrating an example of a procedure of an evaluation data acquisition process. [Figure 14] 10 is a flowchart illustrating an example of a procedure for a deterioration determination process. [Figure 15] FIG. 11 is a sequence diagram illustrating a state monitoring operation executed by the heat storage unit monitoring system in the third embodiment. [Figure 16] FIG. 13 is a sequence diagram illustrating a state monitoring operation executed by a heat storage unit monitoring system in a fourth embodiment. [Figure 17] 10 is a flowchart illustrating a modified example of the deterioration determination process. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] The present specification describes a heat storage unit status monitoring system that is used in a heat exchange system in which a heat storage unit is disposed in a return circuit that returns a heat medium from a controlled object to a chiller device, and that monitors the status of the heat storage unit.

[0033] (First embodiment) The heat exchange system 1 shown in FIG. 1 is incorporated in, for example, a semiconductor manufacturing system that performs an etching process on a wafer. The heat exchange system 1 is disposed on a circulation path that circulates a temperature control fluid between a temperature control member 110, a low-temperature chiller unit 120A, and a high-temperature chiller unit 120B. The semiconductor manufacturing system is an example of a "host system." The temperature control member 110 is an example of a "controlled object." The low-temperature chiller unit 120A and the high-temperature chiller unit 120 are each an example of a "chiller unit." The temperature control fluid is an example of a "heat medium."

[0034] The low-temperature chiller device 120A stores a temperature control fluid (hereinafter referred to as "low-temperature fluid") whose temperature is adjusted to a low-temperature medium setting temperature in a low-temperature tank 122A. The low-temperature fluid is sent to the heat exchange system 1 by a low-temperature pump 124A. The low-temperature medium setting temperature in this embodiment is -10°C. The low-temperature fluid is an example of a "heat medium".

[0035] The high-temperature chiller device 120B stores a temperature control fluid (hereinafter referred to as "high-temperature fluid") whose temperature is adjusted to a high-temperature medium setting temperature in a high-temperature tank 122B. The high-temperature fluid is sent to the heat exchange system 1 by a high-temperature pump 124B. The high-temperature medium setting temperature in this embodiment is 100°C. The high-temperature fluid is an example of a "heat medium".

[0036] The temperature control member 110 is placed in a reaction vessel (not shown), and a wafer (not shown) is placed thereon. The temperature control member 110 is heated and cooled by circulating a temperature control fluid adjusted to a predetermined set temperature (hereinafter referred to as the "circulation circuit set temperature") using a low-temperature fluid and a high-temperature fluid, and can control the temperature of the wafer (not shown).

[0037] The heat exchange system 1 can form an independent temperature control circuit L50 that circulates a temperature control fluid in the temperature control member 110 independently by the output circuit L51, the input circuit L52, and the connection circuit L53 that connects them.

[0038] An output temperature sensor 7 and a flow rate sensor 9 are disposed in the output circuit L51. The output temperature sensor 7 measures the temperature of the temperature control fluid supplied to the temperature control member 110. The flow rate sensor 9 measures the flow rate of the temperature control fluid supplied to the temperature control member 110. An input circuit L52 is disposed with a circulation pump 2 and an input temperature sensor 6. The circulation pump 2 is driven so that the value of the flow rate sensor 9 becomes a designated flow rate. The input temperature sensor 6 measures the temperature of the temperature control fluid output from the temperature control member 110.

[0039] 2, the low-temperature fluid supply circuit L61 connects the output circuit L51 and the low-temperature chiller device 120A. The low-temperature fluid return circuit L62 connects the input circuit L52 and the low-temperature chiller device 120A. The heat exchange system 1 can form a cooling circuit LC that circulates low-temperature fluid between the low-temperature chiller device 120A and the temperature control member 110 to cool the temperature control member 110 by the low-temperature fluid supply circuit L61, the output circuit L51, the input circuit L52, and the low-temperature fluid return circuit L62.

[0040] 3, the high-temperature fluid supply circuit L71 connects the output circuit L51 and the high-temperature chiller device 120B. The high-temperature fluid return circuit L72 connects the input circuit L52 and the high-temperature chiller device 120B. The heat exchange system 1 can form a heating circuit LH that circulates high-temperature fluid between the high-temperature chiller device 120B and the temperature control member 110 to heat the temperature control member 110 by using the high-temperature fluid supply circuit L71, the output circuit L51, the input circuit L52, and the high-temperature fluid return circuit L72.

[0041] A flow rate distribution unit 3 is disposed at a junction P6 where the low-temperature fluid feed circuit L61, the connection circuit L53, and the high-temperature fluid feed circuit L71 connect to the output circuit L51. The flow rate distribution unit 3 is, for example, a spool valve, and includes a first opening proportional unit V1 that adjusts the communication state between the connection circuit L53 and the output circuit L51, a second opening proportional unit V2 that adjusts the communication state between the low-temperature fluid feed circuit L61 and the output circuit L51, and a third opening proportional unit V3 that adjusts the communication state between the high-temperature fluid feed circuit L71 and the output circuit L51. The flow rate distribution unit 3 operates the first to third opening proportional units V1 to V3 in conjunction with each other.

[0042] Check valves CV1, CV2, and CV3 are provided at a branch point P7 where the low-temperature fluid return circuit L62, the connection circuit L53, and the high-temperature fluid return circuit L72 branch off from the input circuit L52. The check valve CV1 is provided in the connection circuit L53 and prevents the temperature control fluid from flowing back from the connection circuit L53 to the input circuit L52. The check valve CV2 is provided in the low-temperature fluid return circuit L62 and prevents the temperature control fluid from flowing back from the low-temperature fluid return circuit L62 to the input circuit L52. The check valve CV3 is provided in the high-temperature fluid return circuit L72 and prevents the temperature control fluid from flowing back from the high-temperature fluid return circuit L72 to the input circuit L52.

[0043] The temperature control fluid that has exchanged heat with the temperature control member 110 is divided into the connection circuit L53, the low-temperature fluid return circuit L62, and the high-temperature fluid return circuit L72 according to the distribution ratio of the flow rate distribution unit 3, and is returned to the low-temperature chiller unit 120A and the high-temperature chiller unit 120B. The returned temperature control fluid has its temperature adjusted by the low-temperature chiller unit 120A and the high-temperature chiller unit 120B, and is supplied to the temperature control member 110.

[0044] In the heat exchange system 1, in order to reduce the temperature adjustment load of the low-temperature chiller unit 120A and the high-temperature chiller unit 120B, a low-temperature heat storage unit 4A is disposed in the low-temperature fluid return circuit L62, and a high-temperature heat storage unit 4B is disposed in the high-temperature fluid return circuit L72. In the low-temperature fluid return circuit L62, a low-temperature throttle valve 8A is disposed between the low-temperature heat storage unit 4A and the low-temperature chiller unit 120A. In the high-temperature fluid return circuit L72, a high-temperature throttle valve 8B is disposed between the high-temperature heat storage unit 4B and the high-temperature chiller unit 120B.

[0045] The low-temperature heat storage unit 4A and the high-temperature heat storage unit 4B store thermal energy during a phase change between solid and liquid. The low-temperature heat storage unit 4A and the high-temperature heat storage unit 4B of this embodiment are filled with a latent heat storage material. The low-temperature heat storage unit 4A and the high-temperature heat storage unit 4B are provided with a heat exchange flow path through which a temperature control fluid flows so as to be able to exchange heat with the latent heat storage material. In order to promote heat exchange between the temperature control fluid and the latent heat storage material, fins are provided in the heat exchange flow path.

[0046] The latent heat storage material of the high temperature heat storage unit 4B has a higher heat storage temperature than the latent heat storage material of the low temperature heat storage unit 4A. The low temperature heat storage unit 4A of this embodiment uses a latent heat storage material with a heat storage temperature of -10°C, and can cool the temperature control fluid returned from the temperature control member 110 to the low temperature chiller device 120A. The high temperature heat storage unit 4B of this embodiment uses a latent heat storage material with a heat storage temperature of 100°C, and can heat the temperature control fluid returned from the temperature control member 110 to the high temperature chiller device 120B.

[0047] The low temperature throttle valve 8A and the high temperature throttle valve 8B adjust the pressure of the temperature adjustment fluid returned from the low temperature heat storage unit 4A and the high temperature heat storage unit 4B to the low temperature chiller device 120A and the high temperature chiller device 120B, respectively.

[0048] The low-temperature fluid forward circuit L61 and the low-temperature fluid return circuit L62 are connected via a low-temperature fluid bypass circuit L63. The low-temperature fluid bypass circuit L63 branches off from the low-temperature fluid forward circuit L61 at a connection point P2A downstream of the flow rate distribution unit 3. The low-temperature fluid bypass circuit L63 is connected to the low-temperature fluid return circuit L62 at a connection point P1A upstream of the low-temperature heat storage unit 4A. The heat exchange system 1 can form a low-temperature independent circuit L60 that circulates low-temperature fluid independently between the low-temperature chiller device 120A and the low-temperature heat storage unit 4A to regenerate the low-temperature heat storage unit 4A by using the low-temperature fluid forward circuit L61, the low-temperature fluid bypass circuit L63, and the low-temperature fluid return circuit L62.

[0049] The high-temperature fluid forward circuit L71 and the high-temperature fluid return circuit L72 are connected via a high-temperature fluid bypass circuit L73. The high-temperature fluid bypass circuit L73 branches off from the high-temperature fluid forward circuit L71 at a connection point P2B downstream of the flow rate distribution unit 3. The high-temperature fluid bypass circuit L73 is connected to the high-temperature fluid return circuit L72 at a connection point P2B upstream of the high-temperature heat storage unit 4B. The heat exchange system 1 can form a high-temperature independent circuit L70 that circulates high-temperature fluid independently between the high-temperature chiller device 120B and the high-temperature heat storage unit 4B to regenerate the high-temperature heat storage unit 4B by using the high-temperature fluid forward circuit L71, the high-temperature fluid bypass circuit L73, and the high-temperature fluid return circuit L72.

[0050] Temperature sensors 5A and 5B are disposed at connection points P2A and P2B, respectively, and measure the temperatures of the low-temperature fluid and the high-temperature fluid supplied to the temperature control member 110.

[0051] 4, the operation of the heat exchange system 1 is controlled by a heat exchange controller 50. The heat exchange controller 50 includes a control unit 51 having a CPU 52 and a memory 53, and a third communication unit 54 and a fourth communication unit 55 are connected to the control unit 51.

[0052] The memory 53 stores various programs and data. The memory 53 is also used as a temporary storage area. The CPU 52 reads out programs from the memory 53 and executes various processes. The third communication unit 54 includes hardware that controls communication with an external device such as a host controller 130 that controls the semiconductor manufacturing system. The fourth communication unit 55 includes hardware that connects to, for example, the circulation pump 2, the flow rate distribution unit 3, the temperature sensor 5A, the temperature sensor 5B, the input temperature sensor 6, the output temperature sensor 7, and the flow rate sensor 9. The communication method of the third communication unit 54 and the fourth communication unit 55 may be wired or wireless.

[0053] In such a heat exchange system 1, the heat exchange controller 50 controls the operation of the flow rate distributor 3 based on the temperatures measured by the temperature sensors 5A and 5B and the temperature measured by the output temperature sensor 7, thereby adjusting the mixing ratio of the temperature control fluid, the low-temperature fluid, and the high-temperature fluid, and adjusting the temperature of the temperature control fluid supplied to the temperature control member 110 to a specified temperature. In this case, the low-temperature heat storage unit 4A and the high-temperature heat storage unit 4B may deteriorate over time because they repeat an operation of cooling or heating the temperature control fluid by heat exchange with the temperature control fluid and an operation of regenerating the temperature control fluid by heat exchange with the low-temperature fluid or the high-temperature fluid.

[0054] Therefore, in the heat exchange system 1, a heat storage unit status monitoring system 30 (hereinafter abbreviated as "monitoring system 30") monitors the status of the low temperature heat storage unit 4A and the high temperature heat storage unit 4B. The monitoring system 30 is composed of a monitoring controller 31, a low temperature inflow temperature sensor 32, a low temperature outflow temperature sensor 33, a high temperature inflow temperature sensor 34, and a high temperature outflow temperature sensor 35.

[0055] As shown in FIG. 1, the low-temperature inflow temperature sensor 32 is disposed between the connection point P1A and the low-temperature heat storage unit 4A, and measures the temperature of the temperature control fluid flowing into the low-temperature heat storage unit 4A (hereinafter referred to as the "low-temperature inflow temperature"). The low-temperature outflow temperature sensor 33 is disposed between the low-temperature heat storage unit 4A and the low-temperature tank 122A, and measures the temperature of the temperature control fluid flowing out from the low-temperature heat storage unit 4A (hereinafter referred to as the "low-temperature outflow temperature"). The high-temperature inflow temperature sensor 34 is disposed between the connection point P1B and the high-temperature heat storage unit 4B, and measures the temperature of the temperature control fluid flowing into the high-temperature heat storage unit 4B (hereinafter referred to as the "high-temperature inflow temperature"). The high-temperature outflow temperature sensor 35 is disposed between the high-temperature heat storage unit 4B and the high-temperature tank 122B, and measures the temperature of the temperature control fluid flowing out from the high-temperature heat storage unit 4B (hereinafter referred to as the "high-temperature outflow temperature").

[0056] The low temperature heat storage unit 4A and the high temperature heat storage unit 4B are examples of "heat storage units." The low temperature inflow temperature sensor 32 and the high temperature inflow temperature sensor 34 are examples of a "temperature sensor" and a "first temperature sensor." The low temperature outflow temperature sensor 33 and the high temperature outflow temperature sensor 35 are examples of a "temperature sensor" and a "second temperature sensor." The low temperature inflow temperature and the high temperature inflow temperature are examples of a "fluid temperature" and a "inflow temperature." The low temperature outflow temperature and the high temperature outflow temperature are examples of a "fluid temperature" and a "outflow temperature."

[0057] As shown in Fig. 4, the monitoring controller 31 includes a control unit 41 having a CPU 42 and a memory 43, and a first communication unit 44, a second communication unit 45, and a notification unit 46 are connected to the control unit 41. The first communication unit 44 is an example of a "communication unit". The memory 43 is an example of a "storage unit". The monitoring controller 31 is an example of a "status monitoring unit".

[0058] The memory 43 stores various programs and data. The memory 43 is also used as a temporary storage area. The CPU 42 reads out programs from the memory 43 and executes various processes. The first communication unit 44 includes hardware that controls communication with an external device such as the upper controller 130. The second communication unit 45 includes hardware that connects to the low-temperature inflow temperature sensor 32, the low-temperature outflow temperature sensor 33, the high-temperature inflow temperature sensor 34, and the high-temperature outflow temperature sensor 35. The communication method of the first communication unit 44 and the second communication unit 45 may be wired or wireless. The notification unit 46 includes hardware that notifies information. The notification unit 46 is, for example, a lamp, a liquid crystal, a speaker, or the like.

[0059] Next, the monitoring operation of the monitoring system 30 will be described. The host controller 130 stores a process recipe for controlling the temperature of the temperature control fluid according to the etching process. The host controller 130 sequentially transmits control signals to the heat exchange controller 50 according to specific process conditions included in the process recipe. The monitoring controller 31 executes various processes for monitoring the states of the low temperature heat storage unit 4A and the high temperature heat storage unit 4B in response to commands from the host controller 130.

[0060] In this embodiment, the process recipe is not changed after the process conditions are determined. Therefore, the heat exchange system 1 repeatedly executes the process under the same process conditions. Therefore, the monitoring controller 31 in this embodiment measures the temperature control fluid flowing through the low-temperature heat storage unit 4A and the high-temperature heat storage unit 4B when the process conditions are determined, and obtains comparison data to be compared in advance.

[0061] Specifically, for example, as shown in the range X0 of Fig. 5, in a low-temperature steady state where the circulation circuit set temperature T5 is maintained at 10°C (arrow A in Fig. 6), the heat exchange system 1 circulates the temperature control fluid, low-temperature fluid, and high-temperature fluid independently through the temperature control independent circuit L50, the low-temperature independent circuit L60, and the high-temperature independent circuit L70, as shown in Fig. 1. In this case, as shown in Fig. 5, the low-temperature inlet temperature T1 and the low-temperature outlet temperature T2 are maintained at -10°C, which is the low-temperature medium set temperature. The high-temperature inlet temperature T3 and the high-temperature outlet temperature T4 are maintained at 100°C, which is the high-temperature medium set temperature.

[0062] 6, when starting an etching process, the upper controller 130 transmits a process start signal to the heat exchange controller 50 (arrow B). Furthermore, the upper controller 130 transmits a first timing determination signal to the monitoring controller 31 (arrow C).

[0063] When the monitoring controller 31 receives the first timing determination signal using the first communication unit 44 (alt: first timing determination signal), it executes a comparison data acquisition process (arrow E). The timing at which the first timing determination signal is received is an example of the "first timing". The first timing determination signal is an example of a "command from a higher-level controller". In this embodiment, the first timing determination signal is output only when the heat exchange system 1 is started for the first time, but it may be output every time the heat exchange system 1 is started. The first timing determination signal may be output periodically, such as once a month, or may be output when a predetermined condition is satisfied, such as every time the number of times the second timing determination signal described later is received is counted a predetermined number of times.

[0064] In the comparison data acquisition process shown in Fig. 7, the CPU 42 of the monitoring controller 31 acquires the low-temperature inflow temperature T1 measured by the low-temperature inflow temperature sensor 32, the low-temperature outflow temperature T2 measured by the low-temperature outflow temperature sensor 33, the high-temperature inflow temperature T3 measured by the high-temperature inflow temperature sensor 34, and the high-temperature outflow temperature T4 measured by the high-temperature outflow temperature sensor 35 using the second communication unit 45, and stores them in the memory 43 (S11). The low-temperature inflow temperature T1 and the high-temperature inflow temperature T3 acquired in S11 are examples of the "first inflow temperature". The CPU 42 uses the first communication unit 44 to determine whether or not a process end signal has been received from the upper controller 130 (S12).

[0065] The CPU 42 continues to store the measured values ​​of the low temperature inlet temperature T1, the low temperature outlet temperature T2, the high temperature inlet temperature T3, and the high temperature outlet temperature T4 in the memory 43 until a process end signal is received (S12: NO). The low temperature inlet temperature T1, the low temperature outlet temperature T2, the high temperature inlet temperature T3, and the high temperature outlet temperature T4 are examples of the "first fluid temperature."

[0066] The process recipe of this embodiment includes, as a specific process condition, a first temperature change condition for changing the circulation circuit set temperature from 10° C. to 80° C. immediately after the start of the process. The upper controller 130 transmits a first temperature change signal based on the first temperature change condition to the heat exchange controller 50.

[0067] When the heat exchange controller 50 receives the first temperature change signal using the third communication unit 54 at t1 in FIG. 5, it calculates the temperature difference between the temperature detected by the output temperature sensor 7 and the circulation circuit set temperature (80°C). Based on the calculated temperature difference and the temperatures detected by the temperature sensors 5A, 5B and the output temperature sensor 7, the heat exchange controller 50 determines the distribution ratio of the flow rate distribution unit 3 so as to raise the temperature of the temperature control fluid supplied to the temperature control member 110. As a result, the high-temperature fluid flows from the high-temperature chiller device 120B to the temperature control member 110. In response to this, the temperature control fluid at 10°C that has been circulating in the temperature control independent circuit L50 flows into the high-temperature fluid return circuit L72. Therefore, as shown in the range X1 in FIG. 5, the high-temperature inflow temperature T3 and the high-temperature outflow temperature T4 drop in temperature.

[0068] The 10°C temperature control fluid that flows into the high-temperature fluid return circuit L72 absorbs heat from the high-temperature heat storage unit 4B and then flows out toward the high-temperature chiller device 120B. Therefore, the high-temperature outflow temperature T4 drops more slowly than the high-temperature inflow temperature T3, and the amount of temperature drop is suppressed. Therefore, the high-temperature chiller device 120B receives the temperature control fluid at a temperature close to that of the high-temperature fluid stored in the high-temperature tank 122B, and the load of heating the temperature control fluid is reduced.

[0069] The process recipe of this embodiment stores, as specific process conditions, a temperature increase processing time, which is the time taken for processing to increase the temperature of the temperature control fluid from 10° C. to 80° C., and a first holding condition, which holds the circulation circuit set temperature T5 at 80° C. after the temperature increase processing time has elapsed. When the temperature increase processing time has elapsed since transmitting the first temperature change signal, the upper controller 130 transmits a first holding signal based on the first holding condition to the heat exchange controller 50.

[0070] When the heat exchange controller 50 receives the first hold signal using the third communication unit 54 at t2 in Fig. 5, it determines the distribution ratio of the flow rate distribution unit 3 so as to maintain the temperature detected by the output temperature sensor 7 at the circulation circuit set temperature (80°C). As a result, for example, a temperature control fluid at 80°C circulates independently in the temperature control independent circuit L50. A high-temperature fluid at 100°C circulates independently in the high-temperature heat storage unit 4B. Therefore, as shown in the range X2 in Fig. 5, the high-temperature inflow temperature T3 and the high-temperature outflow temperature T4 rise.

[0071] In the range X1 in Fig. 5, the high-temperature heat storage unit 4B exchanges heat with a temperature control fluid at, for example, 10°C, and the thermal energy is reduced. The high-temperature fluid circulating in the high-temperature independent circuit L70 dissipates heat to the high-temperature heat storage unit 4B, regenerating the high-temperature heat storage unit 4B. Therefore, the high-temperature outflow temperature T4 rises more slowly than the high-temperature inflow temperature T3 (range X2 in Fig. 5).

[0072] As shown by t3 in FIG. 5, when the high-temperature inflow temperature T3 and the high-temperature outflow temperature T4 reach the high-temperature medium temperature of 100° C., they are maintained in a steady state (range X3 in FIG. 5).

[0073] The process recipe of this embodiment stores, as specific process conditions, a first retention time that specifies the time for which a high-temperature steady state is maintained, and a second temperature change condition that changes the circulation circuit set temperature from 80° C. to 10° C. after the first retention time has elapsed. When the first retention time has elapsed since transmitting the first retention signal, the upper controller 130 transmits a second temperature change signal based on the second temperature change condition to the heat exchange controller 50.

[0074] When the heat exchange controller 50 receives the second temperature change signal using the third communication unit 54 at t4 in FIG. 5 (t4 in FIG. 5), it calculates the temperature difference between the temperature detected by the output temperature sensor 7 and the circulation circuit set temperature (10°C). Based on the calculated temperature difference and the temperatures detected by the temperature sensors 5A, 5B and the output temperature sensor 7, the heat exchange controller 50 determines the distribution ratio of the flow rate distribution unit 3 so as to lower the temperature of the temperature control fluid supplied to the temperature control member 110. As a result, the low-temperature fluid flows from the low-temperature chiller device 120A into the temperature control member 110. In response to this, the temperature control fluid at 80°C that has been circulating through the temperature control independent circuit L50 flows into the low-temperature fluid return circuit L62. Therefore, as shown in the range X4 in FIG. 5, the low-temperature inflow temperature T1 and the low-temperature outflow temperature T2 rise.

[0075] The 80°C temperature control fluid that flows into the low-temperature fluid return circuit L62 absorbs heat from the low-temperature heat storage unit 4A and then flows out toward the low-temperature chiller device 120A. Therefore, the low-temperature outflow temperature T2 rises more slowly than the low-temperature inflow temperature T1, and the amount of temperature rise is suppressed. Therefore, the temperature control fluid flows into the low-temperature chiller device 120A at a temperature close to that of the low-temperature fluid stored in the low-temperature tank 122A, so the load of cooling the temperature control fluid is reduced.

[0076] The process recipe of this embodiment stores, as specific process conditions, a temperature drop processing time, which is the time taken for processing to drop the temperature of the temperature control fluid from 80° C. to 10° C., and a second holding condition, which holds the circulation circuit set temperature T5 at 10° C. after the high temperature processing time has elapsed. When the temperature drop processing time has elapsed after transmitting the second temperature change signal, the upper controller 130 transmits a second holding signal based on the second holding condition to the heat exchange controller 50.

[0077] As shown at t5 in Fig. 5, when the heat exchange controller 50 receives the second hold signal using the third communication unit 54, it determines the distribution ratio of the flow rate distribution unit 3 so as to maintain the temperature detected by the output temperature sensor 7 at the circulation circuit set temperature (10°C). As a result, for example, a temperature control fluid at 10°C circulates independently in the temperature control independent circuit L50. A low-temperature fluid at -10°C circulates independently in the low-temperature heat storage unit 4A. Therefore, as shown in the range X5 in Fig. 5, the low-temperature inflow temperature T1 and the low-temperature outflow temperature T2 drop.

[0078] In the range X4 in Fig. 5, the low-temperature heat storage unit 4A exchanges heat with a temperature control fluid of, for example, 80°C, and the thermal energy is reduced. The low-temperature fluid circulating in the low-temperature independent circuit L60 absorbs heat from the low-temperature heat storage unit 4A and regenerates the low-temperature heat storage unit 4A. Therefore, the low-temperature outflow temperature T2 drops more slowly than the low-temperature inflow temperature T1 (range X5 in Fig. 5).

[0079] As shown by t6 in FIG. 5, when the low-temperature inflow temperature T1 and the low-temperature outflow temperature T2 reach the low-temperature medium temperature of −10° C., they are maintained in a steady state (range X6 in FIG. 5).

[0080] The process recipe of this embodiment stores, as a specific process condition, a second holding time that specifies the time for which the circulation circuit set temperature T5 is held at 10° C. When the second holding time has elapsed since transmitting the second holding signal, the upper controller 130 transmits a process end signal notifying the end of the process to the heat exchange controller 50 and the monitoring controller 31.

[0081] At t7 in Fig. 5, the monitoring controller 31 receives a process end signal using the first communication unit 44. The process end signal is an example of a "command from a higher-level controller." As shown in Fig. 7, when the CPU 42 of the monitoring controller 31 determines that the process end signal has been received (S12: YES), it extracts the inflow peak temperature and the outflow peak temperature (S13).

[0082] For example, as shown in the ranges X1 and X2 in FIG. 8, when the circulation circuit set temperature T5 is changed from a steady state of 10°C to 80°C, the temperature control fluid is heated by heat exchange with the high-temperature heat storage unit 4B. Therefore, a temperature difference ΔFH occurs between the high-temperature inflow temperature T3 and the high-temperature outflow temperature T4. The temperature difference ΔFH when the heat exchange system 1 is in the initial state indicates the initial characteristics of the high-temperature heat storage unit 4B. That is, the amount of heat stored in the high-temperature heat storage unit 4B can be calculated from the temperature change of the high-temperature inflow temperature T3, the temperature change of the high-temperature outflow temperature T4, the specific heat of the temperature control fluid, and the flow rate of the temperature control fluid. In addition, the rate of change K4 of the high-temperature outflow temperature T4 during temperature reduction when the heat exchange system 1 is in the initial state reflects the initial heat exchange capacity of the high-temperature heat storage unit 4B.

[0083] Therefore, the monitoring controller 31 extracts the high-temperature inflow peak temperature PK3 and the high-temperature outflow peak temperature PK4 from the temperature change region (ranges X1 and X2 in Figure 8) when the circulation circuit set temperature T5 is changed from the low-temperature steady temperature of 10°C to 80°C, from the high-temperature inflow peak temperature T3 and the high-temperature outflow temperature T4 stored in the memory 43.

[0084] The high-temperature inflow peak temperature PK3 extracted in S13 is an example of a “first inflow peak value.” The high-temperature outflow peak temperature PK4 is an example of a “first outflow peak value.”

[0085] 7, the CPU 42 of the monitoring controller 31 calculates a first high-temperature heat exchange amount obtained by the difference between the high-temperature inflow peak temperature PK3 and the high-temperature outflow peak temperature PK4 extracted in S13 (S14). The CPU 42 stores the calculated first high-temperature heat exchange amount in a non-volatile area of ​​the memory 43 as high-temperature side comparison data (S15). The first high-temperature heat exchange amount is an example of a "first heat exchange amount."

[0086] Similarly, the temperature difference ΔFC between the low-temperature inflow temperature T1 and the low-temperature outflow temperature T2 in the ranges X4 and X5 in FIG. 9 and the rate of change K2 of the low-temperature outflow temperature T2 during temperature rise reflect the initial characteristics of the low-temperature heat storage unit 4A.

[0087] Therefore, as shown in Fig. 7, the CPU 42 of the monitoring controller 31 extracts the low temperature inflow peak temperature PK1 and the low temperature outflow peak temperature PK2 from the temperature change region (range X4, X5 in Fig. 9) when the circulation circuit set temperature T5 is changed from the high temperature steady temperature 80°C to 10°C from the low temperature inflow peak temperature T1 and the low temperature outflow temperature T2 stored in the memory 43 (S13). The monitoring controller 31 calculates a first low temperature heat exchange amount obtained from the difference between the low temperature inflow peak temperature PK1 and the low temperature outflow peak temperature PK2 (S14), and stores the first low temperature heat exchange amount in the non-volatile region of the memory 43 as low temperature side comparison data (S15). The first low temperature heat exchange amount is an example of the "first heat exchange amount".

[0088] This low-temperature outflow peak temperature is an example of a “first inflow temperature peak value.” The low-temperature outflow peak temperature PK2 is an example of a “first outflow peak temperature.”

[0089] As shown in FIG. 7, when the monitoring controller 31 stores the high temperature side comparison data and the low temperature side comparison data in the memory 43, the monitoring controller 31 ends the comparison data acquisition process.

[0090] Returning to Fig. 6, after executing the comparison data acquisition process and storing the low temperature side comparison data and the high temperature side comparison data in the memory 43, if the monitoring controller 31 receives a second timing judgment signal (alt: second timing judgment signal), it executes the evaluation data acquisition process (arrow I). The timing at which the second timing judgment signal is received is an example of a "second timing". The second timing judgment signal is an example of a "command from a higher-level controller".

[0091] In the evaluation data acquisition process shown in Fig. 10, the CPU 42 of the monitoring controller 31 stores the low temperature inflow temperature T1, the low temperature outflow temperature T2, the high temperature inflow temperature T3, and the high temperature outflow temperature T4, as in the comparison data acquisition process (S21, S22: YES). The low temperature inflow temperature T1, the low temperature outflow temperature T2, the high temperature inflow temperature T3, and the high temperature outflow temperature T4 are examples of the "second fluid temperature". The low temperature inflow temperature T1 and the high temperature inflow temperature T3 acquired in S21 are examples of the "second inflow temperature".

[0092] The CPU 42 extracts the low temperature inflow peak temperature PK1, the low temperature outflow peak temperature PK2, the high temperature inflow peak temperature PK3, and the high temperature outflow peak temperature PK4 from them (S23). The CPU 42 calculates a second high temperature heat exchange amount obtained by the difference between the extracted high temperature inflow peak temperature PK3 and the high temperature outflow peak temperature PK4 (S24), and stores it in the memory 43 as evaluation data on the high temperature side (S25). The CPU 42 also calculates a second low temperature heat exchange amount obtained by the difference between the extracted low temperature inflow peak temperature PK1 and the low temperature outflow peak temperature PK2 (S24), and stores it in the memory 43 as evaluation data on the low temperature side (S25). After that, the CPU 42 ends the evaluation data acquisition process.

[0093] The low temperature inflow peak temperature PK1 and the high temperature inflow peak temperature extracted in S23 are an example of a “second inflow temperature peak value.” The low temperature outflow peak temperature PK2 and the high temperature outflow peak temperature PK4 are an example of a “second outflow peak value.”

[0094] When the evaluation data acquisition process is executed, the heat exchange system 1 executes the process under the same process conditions as when the comparison data acquisition process was executed. When executing this process, the monitoring controller 31 actually measures the low temperature inflow temperature T1, the low temperature outflow temperature T2, the high temperature inflow temperature T3, and the high temperature outflow temperature T4 under the same conditions as when the comparison data was acquired, and acquires low temperature side evaluation data and high temperature side evaluation data. Thus, the low temperature side evaluation data and the high temperature side evaluation data indicate the current characteristics of the low temperature heat storage unit 4A and the high temperature heat storage unit 4B.

[0095] Therefore, as shown in FIG. 6, the monitoring controller 31 executes a determination process for determining the state of the thermal storage unit by comparing the comparison data with the evaluation data (arrow J).

[0096] As shown in FIG. 11, the CPU 42 of the monitoring controller 31 reads out the high temperature side comparison data and the high temperature side evaluation data from the memory 43 (S31).

[0097] The CPU 42 calculates, for example, a low-temperature side inflow temperature peak difference value of the temperature adjustment fluid flowing into the low-temperature heat storage unit 4A (S32). The low-temperature side inflow temperature peak difference value is an example of an "inflow temperature peak difference value". Specifically, the CPU 42 reads out the low-temperature inflow temperature T1 (hereinafter referred to as "first low-temperature inflow temperature T1") stored in the memory 43 in S11 of the comparison data acquisition process shown in FIG. 7, and further reads out the low-temperature inflow temperature T1 (hereinafter referred to as "second low-temperature inflow temperature T1") stored in the memory 43 in S21 of the evaluation data acquisition process shown in FIG. 10. The CPU 42 calculates a low-temperature side inflow temperature peak difference value that is the difference between the first low-temperature inflow temperature peak value, which is the peak value of the read first low-temperature inflow temperature T1, and the second low-temperature inflow temperature peak value, which is the peak value of the second low-temperature inflow temperature T1.

[0098] The memory 43 stores a low-temperature side inflow temperature peak threshold value that is a criterion for determining whether or not an abnormality has occurred outside the low-temperature heat storage unit 4A. The low-temperature side inflow temperature peak threshold value is an example of an "inflow difference threshold value." The CPU 42 determines whether or not the calculated low-temperature side inflow temperature peak difference value is equal to or greater than the low-temperature side inflow temperature peak threshold value stored in the memory 43 (S33). When the CPU 42 determines that the low-temperature side inflow temperature peak difference value is equal to or greater than the low-temperature side inflow temperature peak threshold value (S33: YES), it determines that an abnormality exists outside the low-temperature heat storage unit 4A (S41). In this case, the CPU 42 reports the determination result (S40) and ends the deterioration determination process. That is, the CPU 42 reports an external abnormality without determining the state of the low-temperature heat storage unit 4A.

[0099] The memory 43 stores a high-temperature side inflow temperature peak threshold value that is a criterion for determining whether or not an abnormality has occurred outside the high-temperature heat storage unit 4B. The high-temperature side inflow temperature peak threshold value is an example of an "inflow difference threshold value." As described above, the CPU 42 calculates a high-temperature side inflow temperature peak difference value, which is the difference between the first high-temperature side inflow temperature peak value of the high-temperature inflow temperature T3 (hereinafter referred to as "first high-temperature inflow temperature T3") stored in the memory 43 in S11 of the comparison data acquisition process shown in FIG. 7 and the second high-temperature side inflow temperature peak value of the high-temperature inflow temperature T3 (hereinafter referred to as "second high-temperature inflow temperature T3") stored in the memory 43 in S21 of the evaluation data acquisition process shown in FIG. 10 (S32). The high-temperature side inflow temperature peak difference value is an example of an "inflow temperature peak difference value." If the high temperature side inflow temperature peak difference value is greater than or equal to the high temperature side inflow temperature peak threshold value stored in memory 43 (S33: YES), the CPU 42 determines that there is an abnormality outside the high temperature heat storage unit 4B (S41), reports this fact, and terminates the determination process.

[0100] The user can know that an abnormality has occurred outside the low temperature heat storage unit 4A and the high temperature heat storage unit 4B by the notification from the monitoring controller 31. In addition, when an abnormality has occurred outside the low temperature heat storage unit 4A and the high temperature heat storage unit 4B, it is possible to avoid unnecessary determination of the state of the low temperature heat storage unit 4A and the high temperature heat storage unit 4B.

[0101] On the other hand, if the low temperature side inflow temperature peak difference value is not equal to or greater than the low temperature side inflow temperature peak threshold and the high temperature side inflow temperature peak difference value is not equal to or greater than the high temperature side inflow temperature peak threshold (S33: NO), the CPU 42 determines that there is no abnormality outside the low temperature heat storage unit 4A and the high temperature heat storage unit 4B (S34). In this case, the CPU 42 proceeds to S35. The processes of S32 to S34 and S41 are an example of a "preliminary determination process".

[0102] In S35, the CPU 42 calculates a high temperature side heat exchange differential value which is the difference between the first high temperature side heat exchange amount which is the high temperature side comparison data and the second high temperature side heat exchange amount which is the high temperature side evaluation data (S35).

[0103] The monitoring controller 31 stores a high temperature side difference threshold value used when determining the deterioration of the high temperature heat storage unit 4B in the memory 43. The CPU 42 reads out the high temperature side difference threshold value from the memory 43 (S36). The CPU 42 determines whether the high temperature side heat exchange amount difference value calculated in S35 is equal to or larger than the high temperature side difference threshold value (S37).

[0104] If the calculated high temperature side heat exchange amount difference value is equal to or greater than the high temperature side difference threshold value (S37: YES), the CPU 42 determines that the high temperature heat storage unit 4B is not degraded (S38), since there is a high possibility that the current high temperature heat storage unit 4B maintains the characteristics of the initial state.

[0105] On the other hand, for example, as shown in Fig. 8, when deposits are attached to the heat exchange flow passages and fins of the high temperature heat storage unit 4B and the flow rate of the temperature control fluid is reduced, the heat exchange amount of the high temperature heat storage unit 4B is reduced. Therefore, the amount of temperature drop of the high temperature outflow temperature T4y increases compared to the initial high temperature outflow temperature T4. In other words, the rate of change K4y of the high temperature outflow temperature T4y during temperature drop becomes larger than the rate of change K4 of the initial high temperature outflow temperature T4 during temperature drop. In such a case, the second high temperature side heat exchange differential value becomes smaller than the first high temperature side heat exchange differential value.

[0106] Therefore, if the high temperature side heat exchange amount difference value calculated in S35 is not equal to or greater than the high temperature side difference threshold (S37: NO), the CPU 42 determines that the high temperature heat storage unit 4B has deteriorated (S40). S37, S38, and S40 are an example of a "determination process".

[0107] Similarly, the CPU 42 reads out the low-temperature side comparison data and the low-temperature side evaluation data from the memory 43 (S31), and calculates the low-temperature side heat exchange amount difference value, which is the difference between them (S35). The monitoring controller 31 stores a low-temperature side difference threshold value used when determining the deterioration of the low-temperature heat storage unit 4A. The CPU 42 reads out the low-temperature side difference threshold value from the memory 43 (S36).

[0108] If the low-temperature side heat exchange amount difference value calculated in S35 is equal to or greater than the low-temperature side difference threshold value (S37: YES), the CPU 42 determines that the low-temperature heat storage unit 4A is not degraded (S38).

[0109] On the other hand, for example, as shown in Fig. 9, when the low-temperature heat storage unit 4A deteriorates, the amount of temperature rise of the low-temperature outflow temperature T2y increases from the initial low-temperature outflow temperature T2. In other words, the rate of change K2y during temperature rise of the low-temperature outflow temperature T2y becomes larger than the rate of change K2 during temperature rise of the initial low-temperature outflow temperature T2. In such a case, the second low-temperature side heat exchange differential value becomes smaller than the first low-temperature side heat exchange differential value.

[0110] Therefore, if the calculated low-temperature side heat exchange amount difference value is not greater than or equal to the low-temperature side difference threshold value (S37: NO), the CPU 42 determines that the low-temperature heat storage unit 4A is degraded (S40) since there is a high possibility that the current low-temperature heat storage unit 4A is not maintaining the characteristics of the initial state.

[0111] The CPU 42 notifies the result of the determination in S38 or S40 using the notification unit 46 (S39). This allows the monitoring system 30 to monitor the states of the low temperature heat storage unit 4A and the high temperature heat storage unit 4B while the heat exchange system 1 is executing a process, and can appropriately notify an operator of deterioration over time of the low temperature heat storage unit 4A and the high temperature heat storage unit 4B.

[0112] As shown in FIG. 6, when the monitoring controller 31 finishes the determination process, it transmits temperature data to the upper controller 130 using the first communication unit 44 (arrow K). The process of arrow K is an example of a "notification process". The temperature data includes, for example, the low-temperature inflow temperature T1, the low-temperature outflow temperature T2, the high-temperature inflow temperature T3, and the high-temperature outflow temperature T4 stored in the memory 43 in the evaluation data acquisition process. The temperature data may include the temperature measured by the output temperature sensor 7 and the temperature measured by the input temperature sensor 6. The monitoring controller 31 reduces the memory load by deleting the transmitted temperature data from the memory 43. After that, the monitoring controller 31 ends the monitoring mode.

[0113] Upon receiving the temperature data, the upper controller 130 stores the data in an internal memory (arrow L). The upper controller 130 determines whether or not there is an abnormality in the semiconductor manufacturing system based on the temperature data stored in the internal memory (arrow M).

[0114] As described above, the monitoring system 30 of this embodiment measures the temperature change of the temperature control fluid flowing through the low-temperature heat storage unit 4A and the high-temperature heat storage unit 4B every time the heat exchange system 1 executes a process, and determines the state of the low-temperature heat storage unit 4A and the high-temperature heat storage unit 4B based on the temperature change. Therefore, the monitoring system 30 can detect in advance the deterioration of the low-temperature heat storage unit 4A arranged in the low-temperature fluid return circuit L62 that returns the temperature control fluid from the temperature control member 110 to the low-temperature chiller device 120A, and the high-temperature heat storage unit 4B arranged in the high-temperature fluid return circuit L72 that returns the temperature control fluid from the temperature control member 110 to the high-temperature chiller device 120B.

[0115] The monitoring system 30 of this embodiment determines the state of the low-temperature heat storage unit 4A and the high-temperature heat storage unit 4B by comparing comparison data and evaluation data based on the low-temperature inlet temperature T1, the low-temperature outlet temperature T2, the high-temperature inlet temperature T3, and the high-temperature outlet temperature T4 measured by running a process under the same process conditions in the heat exchange system 1, and thereby can accurately determine the state of the low-temperature heat storage unit 4A and the high-temperature heat storage unit 4B.

[0116] The monitoring system 30 of this embodiment calculates the first and second low-temperature side heat exchange amounts based on the actual measured values ​​of the low-temperature inflow temperature and the low-temperature outflow temperature, and compares the difference between them, that is, the low-temperature side heat exchange amount difference value, with a low-temperature side difference threshold value, to determine the deterioration of the low-temperature heat storage unit 4A. The monitoring system 30 also calculates the first and second high-temperature side heat exchange amounts based on the actual measured values ​​of the high-temperature inflow temperature and the high-temperature outflow temperature, and compares the difference between them, that is, the high-temperature side heat exchange amount difference value, with a high-temperature side difference threshold value, to determine the deterioration of the high-temperature heat storage unit 4B. Thus, the monitoring system 30 can accurately determine the deterioration of the low-temperature heat storage unit 4A and the high-temperature heat storage unit 4B.

[0117] The monitoring system 30 of this embodiment measures the low temperature inflow temperature T1, the low temperature outflow temperature T2, the high temperature inflow temperature T3, and the high temperature outflow temperature T4 and determines the status of the low temperature heat storage unit 4A and the high temperature heat storage unit 4B in response to the first timing determination signal, the second timing determination signal, and the process end signal output from the upper controller 130, thereby reducing the burden of managing the timing of measuring temperatures and determining the status of the heat storage units.

[0118] Second embodiment Next, a second embodiment of a condition monitoring system for a thermal storage unit (hereinafter referred to as "monitoring system") will be described. The monitoring system of this embodiment acquires comparison data and evaluation data based on the low-temperature outflow peak temperature and the high-temperature outflow peak temperature. This is different from the monitoring system 30 of the first embodiment, which acquires comparison data and evaluation data based on the difference between the low-temperature inflow peak temperature and the low-temperature outflow peak temperature, and the difference between the high-temperature inflow peak temperature and the high-temperature outflow peak temperature. Here, configurations different from the first embodiment will be described, and configurations common to the first embodiment will be denoted by the same reference numerals in the drawings and explanations, and explanations will be omitted as appropriate.

[0119] As shown in FIG. 12, in the comparison data acquisition process of this embodiment, the CPU 42 of the monitoring controller 31 stores the low temperature inflow temperature T1, the low temperature outflow temperature T2, the high temperature inflow temperature T3, and the high temperature outflow temperature T4 in the memory 43 from when it receives the first timing judgment signal until it receives the process end signal (S11, S12: NO).

[0120] When the CPU 42 receives the process end signal (S12: YES), it extracts the low-temperature inflow peak temperature PK1 from the low-temperature inflow temperature T1 stored in the memory 43, extracts the low-temperature outflow peak temperature PK2 from the low-temperature outflow temperature T2 (S112), and stores the extracted low-temperature inflow peak temperature PK1 and low-temperature outflow peak temperature PK2 in the memory 43 as low-temperature side comparison data (S113). The CPU 42 extracts the high-temperature inflow peak temperature PK3 from the high-temperature inflow temperature T3 stored in the memory 43, extracts the high-temperature outflow peak temperature PK4 from the high-temperature outflow temperature T4 (S112), and stores the extracted high-temperature inflow peak temperature PK3 and high-temperature outflow peak temperature PK4 in the memory 43 as high-temperature side comparison data (S113). The low-temperature outflow peak temperature PK2 and the high-temperature outflow peak temperature PK4 are examples of the "first peak value".

[0121] In the evaluation data acquisition process shown in FIG. 13, the CPU 42 stores the low temperature inflow temperature T1, the low temperature outflow temperature T2, the high temperature inflow temperature T3, and the high temperature outflow temperature T4 in the memory 43 from when it receives the second timing judgment signal until it receives the process end signal (S21, S22: NO), similar to the comparison data acquisition process shown in FIG. 12.

[0122] The CPU 42 extracts the low temperature outflow peak temperature PK2 and the high temperature outflow peak temperature PK4 from the low temperature outflow temperature T2 and the high temperature outflow temperature T4 (S12: YES, S122), and stores them in the memory 43 as the low temperature side evaluation data and the high temperature side evaluation data (S123). The low temperature outflow peak temperature PK2 and the high temperature outflow peak temperature PK4 are examples of the "second peak value".

[0123] In the deterioration judgment process shown in Fig. 14, when the CPU 42 judges that there is no abnormality in the low temperature heat storage unit 4A and the high temperature heat storage unit 4B (S32, S33: NO, S34), it calculates a high temperature peak difference value which is the difference between the first high temperature peak temperature which is the high temperature side comparison data read in S31 and the second high temperature peak temperature which is the high temperature side evaluation data (S132). The monitoring controller 31 stores in the memory 43 a high temperature side peak threshold value used when judging the deterioration of the high temperature heat storage unit 4B. The CPU 42 reads out the high temperature side peak threshold value from the memory 43 (S133). The CPU 42 judges whether the high temperature side peak difference value calculated in S132 is equal to or less than the high temperature side peak threshold value (S134).

[0124] For example, when changing the circulation circuit set temperature from 10°C to 80°C, if the high temperature heat storage unit 4B deteriorates, the amount of heat absorbed by the temperature control fluid from the high temperature heat storage unit 4B decreases. Therefore, the amount of temperature drop in the high temperature outflow temperature increases. Therefore, the high temperature side peak difference value increases according to the deterioration of the high temperature heat storage unit 4B.

[0125] Therefore, if the high temperature side peak difference value calculated in S132 is equal to or less than the high temperature side peak threshold (S134: YES), the CPU 42 determines that the high temperature heat storage unit 4B is not degraded (S38).If the high temperature side peak difference value calculated is not equal to or less than the high temperature side peak threshold (S134: NO), the CPU 42 determines that the high temperature heat storage unit 4B is degraded (S40).

[0126] The CPU 42 also reads out the low temperature side comparison data and the low temperature side evaluation data from the memory 43 (S31), and calculates the low temperature side peak difference value, which is the difference between them (S132). The monitoring controller 31 stores a low temperature side peak threshold value used when determining the deterioration of the low temperature heat storage unit 4A. The CPU 42 reads out the low temperature side peak threshold value from the memory 43 (S133).

[0127] If the calculated low-temperature peak difference value is equal to or less than the low-temperature peak threshold (S134: YES), the CPU 42 determines that the low-temperature heat storage unit 4A is not degraded (S38). If the calculated low-temperature peak difference value is not equal to or less than the low-temperature peak threshold (S134: NO), the CPU 42 determines that the low-temperature heat storage unit 4A is degraded (S40).

[0128] As described above, the monitoring system of this embodiment judges the deterioration of the high temperature heat storage unit 4B using the high temperature side comparison data (first high temperature outflow peak temperature PK4) and the high temperature side evaluation data (second high temperature outflow peak temperature PK4) based on the actual measurement value of the high temperature outflow temperature T4, so that the deterioration of the high temperature heat storage unit 4B can be judged accurately and simply. Also, the monitoring system of this embodiment judges the deterioration of the low temperature heat storage unit 4A accurately and simply using the low temperature side comparison data (first low temperature outflow peak temperature PK2) and the low temperature side evaluation data (second low temperature outflow peak temperature PK2) based on the actual measurement value of the low temperature outflow temperature T2.

[0129] Third embodiment Next, a third embodiment of the monitoring system will be described. As shown in Fig. 15, the monitoring system of this embodiment judges the deterioration of the low temperature heat storage unit 4A and the high temperature heat storage unit 4B using estimated values ​​of the comparison data. This point differs from the monitoring system 30 of the first embodiment, which judges the state of the low temperature heat storage unit 4A and the high temperature heat storage unit 4B using comparison data based on actual measured values. Here, configurations different from the first embodiment will be described, and configurations common to the first embodiment will be denoted by the same reference numerals in the drawings and explanations, and explanations will be omitted as appropriate.

[0130] The upper controller 130 transmits a process start signal to the heat exchange controller 50 and the monitoring controller 31 (arrow C, Q101). Upon receiving the process start signal, the monitoring controller 31 starts measuring the low temperature inlet temperature T1, the low temperature outlet temperature T2, the high temperature inlet temperature T3, and the high temperature outlet temperature T4 using the low temperature inlet temperature sensor 32, the low temperature outlet temperature sensor 33, the high temperature inlet temperature sensor 34, and the high temperature outlet temperature sensor 35, and stores them in the memory 43 (arrow Q102). The process of Q102 is an example of a "measurement process".

[0131] When the CPU 42 receives a process end signal from the upper controller 130 (arrow Q103), it estimates the low temperature outlet temperature and the high temperature outlet temperature from the low temperature inflow temperature and the high temperature inflow temperature acquired in Q102 (arrow Q104). The process of Q104 is an example of an "estimation process".

[0132] Specifically, the CPU 42 extracts, for example, temperature change data from the high-temperature inflow temperature stored in the memory 43, in which the temperature is lowered from a steady state of 100°C and then increased to 100°C. The memory 43 stores in advance an initial capacity of the high-temperature heat storage unit 4B. The initial capacity is, for example, thermal conductivity. The CPU 42 estimates an estimated value of the high-temperature outflow temperature from the initial capacity of the high-temperature heat storage unit 4B stored in the memory 43 and the extracted temperature change data.

[0133] Similarly, the CPU 42 extracts temperature change data that changes from a steady state from the low-temperature inflow temperature stored in the memory 43. The CPU 42 estimates the low-temperature outflow temperature from the initial capacity of the low-temperature heat storage unit 4A pre-stored in the memory 43 and the extracted temperature change data (arrow Q104).

[0134] The CPU 42 performs a process of comparing the high-temperature outflow temperature estimated value estimated in Q104 with the high-temperature outflow temperature actually measured in Q102 to determine the state of the high-temperature heat storage unit 4B (arrow Q105). The CPU 42 also performs a process of comparing the low-temperature outflow temperature estimated value estimated in Q104 with the low-temperature outflow temperature actually measured in Q102 to determine the state of the low-temperature heat storage unit 4A (arrow Q105).

[0135] In this determination process, for example, the CPU 42 obtains an estimated peak difference value between the peak temperature of the estimated high-temperature outflow temperature and the peak temperature of the measured high-temperature outflow temperature, and if the estimated peak difference value is equal to or less than the estimated peak threshold, determines that the high-temperature heat storage unit 4B is not degraded, and if the estimated peak difference value is not equal to or less than the estimated peak threshold, determines that the high-temperature heat storage unit 4B is degraded. The CPU 42 similarly determines whether the low-temperature heat storage unit 4A is degraded. Then, the CPU 42 notifies the determination result.

[0136] As described above, the monitoring system of this embodiment has high versatility because it can determine the states of the low temperature heat storage unit 4A and the high temperature heat storage unit 4B during the execution of a process in the heat exchange system 1 without obtaining comparison data in advance. Furthermore, the monitoring system of this embodiment is expected to be able to determine the states of the low temperature heat storage unit 4A and the high temperature heat storage unit 4B even when the circulation circuit set temperature is changed for each process.

[0137] (Fourth embodiment) Next, a fourth embodiment of the monitoring system will be described. As shown in FIG. 16, the monitoring system of this embodiment includes a controller 301 in which a monitoring controller 31 and a heat exchange controller 50 are integrally provided, and the comparison data can be reacquired. The controller 301 is an example of a "state monitoring unit." This point differs from the monitoring system 30 of the first embodiment in which a monitoring controller 31 and a heat exchange controller 50 are separately provided, the same process recipe is repeatedly executed, and the comparison data is not reacquired. Here, the configurations different from the first embodiment will be described, and the configurations common to the first embodiment will be denoted by the same reference numerals in the drawings and explanations, and the explanations will be omitted as appropriate.

[0138] When the monitoring system 300 is started for the first time, or when, for example, the process recipe is changed and the host controller 130 wants the monitoring system 300 to reacquire the comparison data, the host controller 130 transmits a first timing determination signal to the controller 301 (N101). The first timing determination signal includes the process recipe to be executed by the heat exchange system 1.

[0139] When the controller 301 receives the first timing determination signal (alt: first timing determination signal), it starts the test mode (arrow N111).

[0140] In the test mode, the controller 301 executes a process based on the received process recipe, and further executes a comparison data acquisition process (arrow N112). Specifically, from the start to the end of a process based on the process recipe, the controller 301 measures a low temperature inlet temperature T1, a low temperature outlet temperature T2, a high temperature inlet temperature T3, and a high temperature outlet temperature T4, and stores them in the memory 43. As in the first embodiment, the controller 301 calculates a first high temperature heat exchange amount and a first low temperature heat exchange amount, and stores them in the memory 43 as high temperature side comparison data and low temperature side comparison data. Thereafter, the controller 301 ends the test mode (arrow N113).

[0141] When the controller 301 receives a second timing judgment signal with a process recipe attached from the upper controller 130 (N101, alt: second timing judgment signal), the controller 301 starts a monitoring mode (N121).

[0142] In the monitoring mode, the controller 301 executes a process based on the received process recipe, and further executes an evaluation data acquisition process (arrow N121). Specifically, from the start to the end of a process based on the process recipe, the controller 301 measures a low temperature inlet temperature T1, a low temperature outlet temperature T2, a high temperature inlet temperature T3, and a high temperature outlet temperature T4, and stores them in the memory 43. As in the first embodiment, the controller 301 calculates a second high temperature heat exchange amount and a second low temperature heat exchange amount, and stores them in the memory 43 as high temperature side evaluation data and low temperature side evaluation data (N122).

[0143] Thereafter, the monitoring controller 31 executes the deterioration determination process (arrow J) in the same manner as in the first embodiment, and ends the monitoring mode (N123). The processes indicated by the arrows N101, N111, and N121 are an example of a "mode switching process".

[0144] As described above, in the monitoring system 300 of this embodiment, the controller 301 measures the low temperature inlet temperature T1, the low temperature outlet temperature T2, the high temperature inlet temperature T3, and the high temperature outlet temperature T4 based on the process recipe received from the upper controller 130, and determines the status of the low temperature heat storage unit 4A and the high temperature heat storage unit 4B. Therefore, the heat storage unit status monitoring system can determine the status of the low temperature heat storage unit 4A and the high temperature heat storage unit 4B by itself while reducing the number of communications with the upper controller 130.

[0145] In addition, the monitoring system 300 of this embodiment switches to test mode when comparison data has not been acquired or when acquired comparison data needs to be changed, and switches to monitoring mode when comparison data has been acquired and the acquired comparison data is not to be changed. Therefore, for example, when the process recipe is changed, comparison data can be re-acquired and the state of the heat storage unit can be accurately determined.

[0146] The present invention is not limited to the above-described embodiment, and can be applied in various ways. For example, the heat exchange system 1 and the monitoring system 30 may be incorporated into a host system in a field other than semiconductor manufacturing.

[0147] The heat exchange system 1 may be disposed on a circulation circuit that circulates a heat medium between one chiller device and the temperature control member 110. In this case, the monitoring system 30 may be configured to dispose an inflow temperature sensor and an outflow temperature sensor on the upstream and downstream sides of a heat storage unit disposed on a return circuit that returns a temperature control fluid from the temperature control member 110 to the chiller device, and monitor the state of the heat storage unit.

[0148] 17, the monitoring system 30 reads out the low-temperature outflow temperature T2 and the high-temperature outflow temperature T4 stored in the memory 43 during the previous process execution (an example of the first process execution) (S201), and calculates the first change rates K2, K4 (S202). The monitoring system 30 reads out the low-temperature outflow temperature T2 and the high-temperature outflow temperature T4 stored in the memory 43 during the current process execution (an example of the second process execution) in which the process is executed under the same process conditions as the previous process immediately after the previous process, and calculates the second change rates K2, K4. If the second change rates K2, K4 deviate from the first change rates K2, K4 beyond a predetermined range (S203: YES), the monitoring system 30 determines that the low-temperature heat storage unit 4A and the high-temperature heat storage unit 4B have deteriorated (S40). If the second change rates K2, K4 do not deviate from the first change rates K2, K4 by more than a predetermined range (S203: NO), the monitoring system 30 determines that the low temperature heat storage unit 4A and the high temperature heat storage unit 4B are not degraded (S38). This allows the monitoring system 30 to quickly detect an abnormality in the low temperature heat storage unit 4A and the high temperature heat storage unit 4B when the low temperature heat storage unit 4A and the high temperature heat storage unit 4B fail due to an abnormal temperature, for example. Even if it is determined that the heat storage unit is not degraded by comparing the difference value between the comparison data and the evaluation data with the threshold value, deterioration of the heat storage unit can be detected in advance by comparing the change rate of the outflow temperature in the previous and next processes.

[0149] 17 may be executed as a separate determination process rather than as a part of the deterioration determination process. S31 to S37 and S41 in FIG 17 may be omitted, and S201 to S203 and S38 to S40 may be executed.

[0150] The process of arrow K in Fig. 6 may be omitted. However, if the monitoring system 30 transmits temperature data to the host controller 130 and the host controller 130 determines an abnormality in the semiconductor manufacturing system based on the temperature data, for example, when the low temperature heat storage unit 4A and the high temperature heat storage unit 4B are in a normal state and the temperature control fluid circulating through the temperature control member 110 is not controlled to the circulation circuit set temperature T5, the host controller 130 can be made to detect an abnormality in the semiconductor manufacturing system.

[0151] The monitoring system 30 may monitor the temperature change and determine the deterioration of the heat storage unit when the temperature of the temperature control fluid flowing through the heat storage unit changes from the steady state by a specified temperature or more, instead of receiving a command or a process recipe from the upper controller 130. In this way, the monitoring system 30 can determine the state of the heat storage unit by itself without communicating with an external device such as the upper controller 130.

[0152] The advance judgment process shown in S32 to S34 and S40 in Figures 11, 14, 17, etc. may be omitted. However, if the inflow temperature peak value, which is the difference between the inflow temperature peak value acquired when the comparison data acquisition process is executed and the inflow temperature peak value acquired when the evaluation data acquisition process is executed, is equal to or greater than the inflow difference threshold, there is a high possibility that an abnormality exists other than in the heat storage unit 4, so by not performing the judgment process, it is possible to avoid performing unnecessary judgment processes in a situation where the judgment accuracy is reduced.

[0153] The monitoring controller 31 may be integrated into the heat exchange controller 50 or the chiller controller 140.

[0154] In the above embodiment, the temperature measurement value is stored from the start to the end of one process, but it is possible to store the temperature measurement value in the area where the circulation circuit set temperature is changed (X1, X4 in FIG. 5) and not to store the temperature measurement value in the area where the circulation circuit set temperature is kept constant (X3, X6 in FIG. 5). This reduces the amount of memory 43 used.

[0155] The monitoring controller 31 in the above embodiment receives the second timing judgment signal once in one process. In contrast, for example, when the temperature of the temperature control fluid is changed stepwise to the circulation circuit set temperature in one process, the monitoring controller 31 may individually receive the first timing judgment signal or the second timing judgment signal from the upper controller with a number assigned thereto, such as temperature increase conditions 1, 2, 3 or temperature decrease conditions 1, 2, 3, and execute the comparison data acquisition process or the evaluation data acquisition process each time the signal is received.

[0156] In the above embodiment, the monitoring controller 31 executes the evaluation data acquisition process and the judgment process every time a process is executed. In contrast, the monitoring controller 31 may execute the evaluation data acquisition process and the judgment process every other process. However, by executing the evaluation data acquisition process and the judgment process every process to monitor the state of the heat storage unit, the monitoring controller 31 can detect a change in the state of the heat storage unit at an early stage.

[0157] The controller 301 of the fourth embodiment may switch between the test mode and the monitoring mode by its own judgment, not by a command from the upper controller 130. For example, when the controller 301 receives a process recipe in a state where the comparison data is not stored, the controller 301 judges that the comparison data has not been acquired, and executes the test mode. Also, when the controller 301 receives a process recipe in a state where the comparison data is stored, and the received process recipe is different from a past process recipe, the controller 301 judges that the acquired comparison data is to be changed, and executes the test mode. When the controller 301 receives a process recipe in a state where the comparison data is stored, and the received process recipe is the same as a past process recipe, the controller 301 judges that the comparison data has been acquired and that the acquired comparison data is not to be changed, and executes the monitoring mode. [Explanation of symbols]

[0158] 1. Heat exchange system 4A Low temperature heat storage unit 4B High temperature heat storage unit 30 Condition monitoring system for thermal storage units 31 Controller (an example of a status monitoring unit) 32 Low temperature inlet temperature sensor (an example of a temperature sensor) 33 Low temperature outflow temperature sensor (example of temperature sensor) 34 High temperature inflow temperature sensor (example of temperature sensor) 35 High temperature outflow temperature sensor (example of temperature sensor) L62 Low temperature fluid return circuit (example of temperature sensor) L72 High temperature fluid return circuit (example of temperature sensor) 110 Temperature control components (an example of a controlled object) 120A low temperature chiller unit 120B High temperature chiller unit

Claims

1. The present invention is used in a heat exchange system including a return circuit for returning a heat medium circulating between a controlled object and a chiller to the chiller, and a heat storage unit disposed in the return circuit for exchanging heat with the heat medium, A temperature sensor that measures a fluid temperature of the heat medium flowing through the heat storage unit; a state monitoring unit that measures a change in temperature of the heat medium circulating through the heat storage unit using the temperature sensor when the heat exchange system executes a process of changing the temperature of the heat medium circulating through the controlled object, and determines a state of the heat storage unit based on the temperature change; having The thermal storage unit status monitoring system is configured as follows.

2. 2. The thermal storage unit state monitoring system according to claim 1, The state monitoring unit is a comparison data acquisition process for acquiring comparison data based on a first fluid temperature measured by the temperature sensor when the heat exchange system executes a specific process condition at a first timing; an evaluation data acquisition process for acquiring evaluation data corresponding to the comparison data based on a second fluid temperature measured by the temperature sensor when the heat exchange system executes the specific process condition at a second timing after the comparison data acquisition process is executed; a determination process for determining a state of the heat storage unit based on the comparison data and the evaluation data; Execute The thermal storage unit status monitoring system is configured as follows.

3. 3. The heat storage unit state monitoring system according to claim 2, The temperature sensor is A first temperature sensor that measures an inflow temperature, which is the temperature of the heat medium flowing into the heat storage unit; A second temperature sensor that measures an outflow temperature of the heat medium flowing out from the heat storage unit; and the comparison data is a first heat exchange amount calculated from a difference between a first inflow peak value, which is a peak value of the inflow temperature measured by the first temperature sensor, and a first outflow peak value, which is a peak value of the outflow temperature measured by the second temperature sensor; the evaluation data is a second heat exchange amount calculated from a difference between a second inflow peak value, which is a peak value of the inflow temperature measured by the first temperature sensor, and a second outflow peak value, which is a peak value of the outflow temperature measured by the second temperature sensor; The determination process includes: calculating a heat exchange difference value which is a difference between the first heat exchange amount and the second heat exchange amount, and determining that the heat storage unit is not degraded if the heat exchange difference value is equal to or greater than a difference threshold value, and determining that the heat storage unit is degraded if the heat exchange difference value is not equal to or greater than the difference threshold value; The thermal storage unit status monitoring system is configured as follows.

4. 3. The heat storage unit state monitoring system according to claim 2, The temperature sensor measures an outflow temperature which is a temperature of the heat medium flowing out from the heat storage unit, the comparison data is a first peak value that is a peak value of the outflow temperature measured by the temperature sensor, the evaluation data is a second peak value that is a peak value of the outflow temperature measured by the temperature sensor, The determination process includes: calculating a peak difference value which is a difference between the first peak value and the second peak value, and determining that the heat storage unit is not degraded if the peak difference value is equal to or less than a peak threshold value, and determining that the heat storage unit is degraded if the peak difference value is not equal to or less than the peak threshold value; The thermal storage unit status monitoring system is configured as follows.

5. 3. The heat storage unit state monitoring system according to claim 2, The temperature sensor includes an inflow temperature sensor that measures an inflow temperature, which is a temperature of the heat medium flowing into the heat storage unit, The state monitoring unit is When the comparison data acquisition process is executed, a first inflow temperature measured by the inflow temperature sensor is acquired; When the evaluation data acquisition process is executed, a second inflow temperature measured by the inflow temperature sensor is acquired; Before executing the determination process, a pre-determination process is executed to determine whether an inflow temperature peak difference value, which is a difference between a first inflow temperature peak value that is a peak value of the first inflow temperature and a second inflow temperature peak value that is a peak value of the second inflow temperature, is equal to or greater than an inflow difference threshold value; When it is determined in the pre-determination process that the inflow temperature peak difference value is equal to or greater than the inflow difference threshold, the determination process is not executed, and when it is determined in the pre-determination process that the inflow temperature peak difference value is not equal to or greater than the inflow difference threshold, the determination process is executed. The thermal storage unit status monitoring system is configured as follows.

6. 2. The thermal storage unit state monitoring system according to claim 1, The temperature sensor measures an outflow temperature which is a temperature of the heat medium flowing out from the heat storage unit, The state monitoring unit is a first rate of change at which the outflow temperature measured by the temperature sensor changes from a steady temperature is calculated during execution of a first process, and a second rate of change at which the outflow temperature measured by the temperature sensor changes from a steady temperature is calculated during a second process in which a process is executed immediately after the first process under the same process conditions as the first process, and if the second rate of change deviates from the first rate of change by more than a predetermined range, it is determined that the heat storage unit has deteriorated. The thermal storage unit status monitoring system is configured as follows.

7. 2. The thermal storage unit state monitoring system according to claim 1, The temperature sensor is A first temperature sensor that measures an inflow temperature, which is the temperature of the heat medium flowing into the heat storage unit; A second temperature sensor that measures an outflow temperature of the heat medium flowing out from the heat storage unit; and The state monitoring unit is a measurement process for measuring the inflow temperature using the first temperature sensor and further measuring the outflow temperature using the second temperature sensor when changing a temperature of the heat medium circulating through the control object; an estimation process of estimating an outflow temperature estimate of the heat medium flowing out from the heat storage unit based on the inflow temperature measured in the measurement process; a determination process of comparing the outflow temperature estimated value estimated in the estimation process with the outflow temperature measured in the measurement process to determine a state of the heat storage unit; Execute The thermal storage unit status monitoring system is configured as follows.

8. 2. The thermal storage unit state monitoring system according to claim 1, A communication unit is provided for connecting to a host controller that controls a host system. The state monitoring unit monitors the temperature change of the heat medium and determines deterioration of the heat storage unit in response to a command from the upper controller. The thermal storage unit status monitoring system is configured as follows.

9. 2. The thermal storage unit state monitoring system according to claim 1, The state monitoring unit monitors the temperature change of the heat medium and determines deterioration of the heat storage unit when the fluid temperature measured by the temperature sensor changes from a steady state by a specified temperature or more. The thermal storage unit status monitoring system is configured as follows.

10. 2. The thermal storage unit state monitoring system according to claim 1, a communication unit communicably connected to a host controller that controls a host system, the host controller transmitting a process recipe including process conditions for controlling a temperature of the heat medium circulating through the object to be controlled; the state monitoring unit receives the process recipe using the communication unit, and monitors the temperature change of the heat medium and determines deterioration of the heat storage unit in accordance with the process conditions included in the received process recipe. The thermal storage unit status monitoring system is configured as follows.

11. 3. The heat storage unit state monitoring system according to claim 2, The state monitoring unit executes a mode switching process, The mode switching process includes: when the comparison data has not been acquired, or when the acquired comparison data is to be changed, switching to a test mode in which the comparison data acquisition process is executed; switching to a monitoring mode in which the evaluation data acquisition process and the determination process are executed when the comparison data has already been acquired and the acquired comparison data is not to be changed; The thermal storage unit status monitoring system is configured as follows.

12. 2. The thermal storage unit state monitoring system according to claim 1, a communication unit communicably connected to a host controller that controls a host system that executes a process using the control object, The state monitoring unit is a notification process for notifying the upper controller of temperature data based on the fluid temperature measured by the temperature sensor using the communication unit, and the upper controller determines whether or not there is an abnormality in the upper system based on the temperature data. The thermal storage unit status monitoring system is configured as follows.

Images