Temperature controlling device

Abstract

To enable a temperature of a fluid to be adjusted with high precision.SOLUTION: A temperature controlling device comprises: a circulation flow path through which a fluid flows; a heating / cooling unit for heating or cooling the fluid flowing through the circulation flow path, in which a plurality of heating / cooling units is arranged in series in the circulation flow path; and a controller that controls the heating / cooling unit. After the controller starts operation, until the outlet temperature of the fluid reaches a target temperature, the controller controls the temperature of the fluid by controlling the heating / cooling unit through feed forward and feedback; and after the outlet temperature of the fluid reaches a target temperature, the controller shuts down or sets outputs of one or more of the heating / cooling units to a fixed value depending on a magnitude of a disturbance.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a temperature control device. [Background technology]

[0002] Patent Document 1 discloses a temperature control device having a plurality of fluid reservoirs equipped with heating and cooling units arranged in series, parallel, or a combination thereof in the middle of a fluid flow path. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-077165 Summary of the Invention [Problem to be solved by the invention]

[0004] In the technology described in Patent Document 1, even when the temperature difference to be adjusted is small and temperature adjustment is possible with one heating / cooling unit, all heating / cooling units are used to control the temperature. This results in redundant heating / cooling units, and depending on the temperature difference to be adjusted and the resolution of the heating / cooling units, it can become difficult to adjust the temperature with high precision in proportion to the number of heating / cooling units.

[0005] An aspect of the present invention aims to make it possible to adjust the temperature of a fluid with high precision. [Means for solving the problem]

[0006] According to one aspect of the present invention, there is provided a temperature control device comprising: a circulation flow path through which a fluid flows; a plurality of heating and cooling units arranged in series in the circulation flow path for heating or cooling the fluid flowing through the circulation flow path; and a controller for controlling the heating and cooling units, wherein the controller regulates the temperature of the fluid by feedforward control and feedback control of the heating and cooling units after operation starts until the outlet temperature of the fluid reaches a target temperature, and after the outlet temperature of the fluid reaches the target temperature, stops the output of one or more of the heating and cooling units or sets them to a fixed value depending on the magnitude of the disturbance. [Effects of the Invention]

[0007] According to the aspects of the present invention, the temperature of the fluid can be adjusted with high precision. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram showing an example of a temperature control device according to an embodiment. [Figure 2] FIG. 2 is a diagram illustrating an example of a controller according to the embodiment. [Figure 3] FIG. 3 is a diagram showing an example of operation of the temperature control device. [Figure 4] FIG. 4 is a diagram schematically illustrating another example of the controller according to the embodiment. [Figure 5] FIG. 5 is a diagram schematically illustrating another example of the controller according to the embodiment. [Figure 6] FIG. 6 is a flowchart showing a temperature control method of the temperature control device according to the embodiment. [Figure 7] FIG. 7 is a diagram showing the controllability of the outlet temperature with respect to fluctuations in the inlet temperature of the fluid. [Figure 8] FIG. 8 is a diagram showing the behavior of the manipulated variable. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited thereto. The components of the embodiments described below can be combined as appropriate. In addition, some components may not be used.

[0010] [Embodiment] <Temperature control device> An embodiment will now be described. Fig. 1 is a schematic diagram showing an example of a temperature control device according to an embodiment. The temperature control device 1 includes a tank 2, a pump 3, a heating / cooling unit 4, a circulation flow path 10, a flow rate sensor 11, an inlet temperature sensor 12, an outlet temperature sensor 13, a supply port 17, a return port 18, a fluid addition port 19, and a controller 20.

[0011] Tank 2 stores the fluid to be supplied to external process device 100. Pump 3 is connected downstream of tank 2. Pump 3 is connected upstream of heating and cooling unit 4. The fluid stored in tank 2 is pumped by pump 3 and passes through heating and cooling unit 4. The supply amount of fluid supplied from tank 2 to heating and cooling unit 4 via pump 3 is denoted as Q.

[0012] The fluid supplied to the external process device 100 that is not used and is discharged is recovered in the tank 2 via the return port 18. The flow rate of the fluid used in the process 101 of the external process device 100 is designated as Qp. The flow rate of the fluid recovered to the tank 2 via the return port 18 is designated as Qr.

[0013] When the fluid in the tank 2 falls below a predetermined threshold, a required amount of new fluid is supplied from the fluid addition port 19. The flow rate of the fluid added to the tank 2 from outside the temperature control device 1 via the fluid addition port 19 is defined as Qs.

[0014] The heating and cooling unit 4 is capable of at least one of heating and cooling the fluid supplied to the external process equipment 100. The heating and cooling unit 4 is a container having a certain volume and equipped with an inlet and an outlet for the fluid. For example, when the external process equipment 100 is a pure water heating device, the heating and cooling unit 4 is equipped with a halogen lamp heater in a quartz bottle in which the inlet and outlet are arranged, and heats the pure water by radiant heat.

[0015] The heating and cooling unit 4 is configured with two or more heating and cooling units 4 connected in series or in parallel, or a combination thereof. The heating and cooling units 4 are controlled by a controller 20 so that the outlet temperature PV3 of the fluid passing therethrough becomes the target temperature SV. In this embodiment, the heating and cooling units 4 are configured with three heating and cooling units 4a, 4b, and 4c connected in series. When there is no particular need to distinguish between the heating and cooling unit 4a, the heating and cooling unit 4b, and the heating and cooling unit 4c, they will be simply referred to as the heating and cooling unit 4.

[0016] The circulation flow path 10 is a flow path through which a fluid supplied to an external process device 100 circulates. The circulation flow path 10 is provided with a tank 2, a pump 3, a heating / cooling unit 4, a flow rate sensor 11, an inlet temperature sensor 12, an outlet temperature sensor 13, a supply port 17, a return port 18, and a process 101 of the external process device 100 via a valve 102.

[0017] The flow rate sensor 11 is disposed between the tank 2 and the heating and cooling unit 4. The flow rate sensor 11 is disposed between the pump 3 and the heating and cooling unit 4a, which is the most upstream of the heating and cooling units 4. The flow rate sensor 11 measures the amount Q of fluid supplied to the heating and cooling unit 4.

[0018] The inlet temperature sensor 12 is disposed between the tank 2 and the heating and cooling unit 4. The inlet temperature sensor 12 is disposed between the pump 3 and the most upstream heating and cooling unit 4a of the heating and cooling units 4. The inlet temperature sensor 12 measures the inlet temperature Tin of the fluid, which is the temperature of the fluid flowing into the most upstream heating and cooling unit 4.

[0019] The outlet temperature sensor 13 is disposed between the heating and cooling unit 4 and the supply port 17 to the external process device 100. The outlet temperature sensor 13 is disposed between the outlet of the most downstream heating and cooling unit 4c of the heating and cooling units 4 and the supply port 17 to the external process device 100. The outlet temperature sensor 13 measures the outlet temperature PV3 of the fluid.

[0020] The supply port 17 is a port for supplying a fluid to an external process device 100 provided downstream of the heating and cooling unit 4. The supply port 17 supplies the fluid whose temperature has been adjusted by the heating and cooling unit 4 to the external process device 100.

[0021] The return port 18 is a port that receives the return fluid from the external process device 100 into the tank 2. The return port 18 recovers excess fluid in the external process device 100 into the tank 2. The flow rate of the fluid recovered into the tank 2 via the return port 18 is Qr.

[0022] The fluid addition port 19 is a port for adding new fluid to the tank 2 from outside the temperature control device 1. The flow rate of the new fluid added to the tank 2 via the fluid addition port 19 is Qs. The fluid addition port 19 is opened when the fluid in the tank 2 falls below a predetermined threshold.

[0023] <controller> The controller 20 calculates the manipulated variable MV of each heating and cooling unit 4 relative to the target temperature SV of the fluid based on the measurement results of the flow rate sensor 11, the inlet temperature sensor 12, and the outlet temperature sensor 13. The controller 20 calculates the manipulated variable MV1 of the heating and cooling unit 4a, the manipulated variable MV2 of the heating and cooling unit 4b, and the manipulated variable MV3 of the heating and cooling unit 4c relative to the target temperature SV of the fluid based on the supply rate Q measured by the flow rate sensor 11, the inlet temperature Tin measured by the inlet temperature sensor 12, and the outlet temperature PV3 measured by the outlet temperature sensor 13. The controller 20 operates each heating and cooling unit 4 in accordance with the calculated manipulated variable to control the outlet temperature PV2 to a desired temperature.

[0024] After the temperature control device 1 starts operating, when the outlet temperature PV3 reaches the target temperature SV, the controller 20 stops or sets to a fixed value the output of one or more heating and cooling units 4 in accordance with the power required for heating in the heating and cooling units 4. In the embodiment, after the temperature control device 1 starts operating, when the outlet temperature PV3 reaches the target temperature SV, the controller 20 stops or sets to a fixed value the output of one or more heating and cooling units 4 from upstream of the heating and cooling unit 4 in accordance with the power required.

[0025] The required power is calculated based on the inlet temperature Tin of the fluid and the flow rate Qs of the new fluid added from outside. The required power corresponding to the fluctuation of the inlet temperature Tin of the fluid and the flow rate Qs of the new fluid added from outside is assumed to be calculated in advance.

[0026] The basic configuration of the feedback control unit 22 and the feedforward control unit 23 in the controller 20 will be described using Fig. 2. Fig. 2 is a diagram schematically illustrating an example of a controller according to an embodiment. The controller 20 includes an SV distributor 21, a first feedback control unit 22a, a second feedback control unit 22b, a third feedback control unit 22c, a first feedforward control unit 23a, a second feedforward control unit 23b, and a third feedforward control unit 23c.

[0027] The first feedback control unit 22a, the second feedback control unit 22b, and the third feedback control unit 22c use, for example, a PID (Proportional Integral Differential) controller. The first feedback control unit 22a calculates a feedback amount FB1 for the heating and cooling unit 4a by using the deviation e1 between the target temperature SV1 distributed to the heating and cooling unit 4a by the SV distributor 21, which receives the target temperature SV and the inlet temperature Tin as inputs, and the outlet temperature PV1 of the heating and cooling unit 4a. The second feedback control unit 22b calculates a feedback amount FB2 for the heating and cooling unit 4b by using the deviation e2 between the target temperature SV2 distributed to the heating and cooling unit 4b by the SV distributor 21, which receives the target temperature SV and the inlet temperature Tin as inputs, and the outlet temperature PV2 of the heating and cooling unit 4b. The third feedback control unit 22c calculates the feedback amount FB3 for the heating and cooling unit 4c by taking the deviation e3 between the target temperature SV3 distributed to the heating and cooling unit 4c by the SV distributor 21, which receives the target temperature SV and the inlet temperature Tin as input, and the outlet temperature PV3 of the heating and cooling unit 4c. Here, the outlet temperature PV1 of the heating and cooling unit 4a and the outlet temperature PV2 of the heating and cooling unit 4b are estimated as estimated temperatures PV1h and PV2h by an estimator. A commonly known calculation method such as an observer is used as the estimator.

[0028] The first feedforward control unit 23a receives as input the target temperature SV1 distributed to the heating and cooling unit 4a by the SV distributor 21, which receives as input the target temperature SV and the inlet temperature Tin, the inlet temperature Tin, and the supply rate Q, and calculates a feedforward amount FF1 for the heating and cooling unit 4a. The second feedforward control unit 23b receives as input the target temperature SV2 distributed to the heating and cooling unit 4b by the SV distributor 21, which receives as input the target temperature SV and the inlet temperature Tin, the outlet temperature PV1 of the heating and cooling unit 4a, and the supply rate Q, and calculates a feedforward amount FF2 for the heating and cooling unit 4b. The third feedforward control unit 23c receives as input the target temperature SV3 distributed to the heating and cooling unit 4c by the SV distributor 21, which receives as input the target temperature SV and the inlet temperature Tin, the outlet temperature PV2 of the heating and cooling unit 4b, and the supply rate Q, and calculates a feedforward amount FF3.

[0029] The feedforward control unit 23 can more effectively suppress fluctuations in the inlet temperature and flow rate of each heating and cooling unit 4.

[0030] The final manipulated variable MV of each heating / cooling unit 4 is obtained by adding the calculated feedforward variable to each feedback variable. The final manipulated variable MV of heating / cooling unit 4a is obtained by adding feedforward variable FF1 to feedback variable FB1. The final manipulated variable MV of heating / cooling unit 4b is obtained by adding feedforward variable FF2 to feedback variable FB2. The final manipulated variable MV of heating / cooling unit 4c is obtained by adding feedforward variable FF3 to feedback variable FB3.

[0031] The feedforward amount FFi is calculated, for example, by the following formula: FFi (S) indicates the dynamic characteristic part, and K indicates the coefficient.

[0032]

number

[0033] An example of operation of the temperature control device 1 will be described using Figure 3. Figure 3 is a diagram showing an example of operation of the temperature control device. In this example, the target temperature SV of the fluid supplied to the external process device 100 is 70°C. After the temperature control device 1 starts operating, the fluid is heated by the heating / cooling unit 4, and the outlet temperature PV3 of the fluid reaches the target temperature SV of 70°C.

[0034] Before the process of external process device 100 starts, the fluid supplied to external process device 100 is not used and is returned to tank 2 via return port 18. For this reason, the temperature of the fluid in tank 2 gradually rises, and the fluid inlet temperature Tin, which is the temperature of the fluid supplied to heating and cooling unit 4, also gradually rises. As the fluid inlet temperature Tin rises, the power required for heating in heating and cooling unit 4 decreases, and the operation value MV of heating and cooling unit 4 decreases.

[0035] After the fluid outlet temperature PV3 reaches the target temperature SV, the process of the external process device 100 begins. During the process of the external process device 100, a certain amount of fluid is used within the external process device 100. Because some of the fluid supplied to the external process device 100 is not recovered, the amount of fluid in the tank 2 decreases. When the fluid in the tank 2 falls below a predetermined threshold, room temperature fluid is supplied from the fluid addition port 19. This reduces the temperature of the fluid in the tank 2, and the fluid inlet temperature Tin, which is the temperature of the fluid supplied to the heating and cooling unit 4, also decreases. Fluctuations in the fluid inlet temperature Tin lead to fluctuations in the outlet temperature PV3. Therefore, the feedback control unit 22 and the feedforward control unit 23 calculate the manipulated variable to suppress fluctuations in the outlet temperature PV3.

[0036] During a process in the external process equipment 100, the sum of the manipulated variables MV of the heating and cooling units 4 is smaller than the manipulated variable corresponding to the maximum output of a single heating and cooling unit 4. In a situation where one heating and cooling unit 4 is sufficient for temperature control, using three heating and cooling units 4 is redundant and reduces the overall resolution of the heating and cooling units 4. Therefore, after the fluid outlet temperature PV3 reaches the target temperature SV, the output of some of the heating and cooling units 4 is stopped or set to a fixed value depending on the power required for heating in the heating and cooling units 4. For example, in the case of FIG. 3, the output of the upstream heating and cooling units 4a and 4b is stopped or set to a fixed value around 700 seconds. This allows the temperature to be controlled according to the resolution of the heating and cooling unit 4c.

[0037] 4 shows an example of the configuration of feedforward control and feedback control in the controller 20 when the outputs of the heating and cooling units 4a and 4b are set to fixed values ​​MV1 and MV2. FIG. 4 is a diagram schematically showing another example of a controller according to an embodiment. The third feedback control unit 22c is the same as that shown in FIG. 2. The third feedforward control unit 23c receives as input the target temperature SV3 distributed to the heating and cooling unit 4c from the SV distributor 21, which receives as input the target temperature SV and the inlet temperature Tin, the inlet temperature Tin of the fluid, and the supply amount Q, and calculates the feedforward amount FF3b of the heating and cooling unit 4c.

[0038] In FIG. 4, the outputs of heating and cooling units 4a and 4b are set to fixed values ​​MV1 and MV2. A transmission delay occurs as the signals pass through heating and cooling units 4a and 4b upstream of heating and cooling unit 4c. A compensation time leeway occurs in third feedforward control unit 23c. The feedforward amount FF3b of heating and cooling unit 4c is calculated by the following equation, similar to equation (1).

[0039]

number

[0040] FIG. 5 shows an example of the configuration of feedforward control and feedback control in the controller 20 when the output of the heating and cooling unit 4a is set to a fixed value MV1. FIG. 5 is a diagram schematically showing another example of a controller according to an embodiment. The second feedback control unit 22b, the third feedback control unit 22c, and the third feedforward control unit 23c are the same as those in FIG. 2. The second feedforward control unit 23b receives as input the target temperature SV2 distributed to the heating and cooling unit 4b from the SV distributor 21, the inlet temperature Tin of the fluid, and the supply rate Q, and calculates the feedforward amount FF2b of the heating and cooling unit 4b. The feedforward amount FF2b of the heating and cooling unit 4b is calculated using the following equation:

[0041]

number

[0042] <Temperature control method> An example of a temperature control method of the temperature control device will be described with reference to Fig. 6. Fig. 6 is a flowchart showing the temperature control method of the temperature control device according to the embodiment. When the temperature control device 1 is started up, the process of the flowchart shown in Fig. 6 is executed at predetermined time intervals.

[0043] The controller 20 receives the target temperature SV, inlet temperature Tin, outlet temperature PV3, supply rate Q, manipulated variable MV1, manipulated variable MV2, and manipulated variable MV3 (step ST11). The target temperature SV is stored, for example, in a memory unit (not shown) of the temperature control device 1. The inlet temperature Tin is acquired from the inlet temperature sensor 12. The outlet temperature PV3 is acquired from the outlet temperature sensor 13. The supply rate Q is acquired from the flow rate sensor 11. The manipulated variables MV1, MV2, and MV3 are acquired as current manipulated variables from the heating and cooling units 4a, 4b, and 4c.

[0044] The controller 20 uses the estimator to calculate the estimated temperatures PV1h and PV2h from the various values ​​acquired in step ST11 (step ST12).

[0045] The controller 20 calculates a target temperature SV1 for the heating and cooling unit 4a, a target temperature SV2 for the heating and cooling unit 4b, and a target temperature SV3 for the heating and cooling unit 4c using the SV distributor 21. The controller 20 distributes the target temperatures SV for the heating and cooling units 4a, 4b, and 4c as the target temperatures SV1 for the heating and cooling unit 4a, SV2 for the heating and cooling unit 4b, and SV3 for the heating and cooling unit 4c using the SV distributor 21.

[0046] The controller 20 calculates the feedback amounts FB1, FB2, and FB3 (step ST14). The controller 20 determines deviations from the target temperatures SV1, SV2, SV3, outlet temperature PV3, estimated temperatures PV1h, and PV2h, and calculates the feedback amounts FB1, FB2, and FB3 using the first feedback control unit 22a, the second feedback control unit 22b, and the third feedback control unit 22c. The algorithm for calculating the feedback amounts FB1, FB2, and FB3 is as described above.

[0047] The controller 20 calculates the feedforward amounts FF1, FF2, FF3, FF2b, and FF3b (step ST15). The controller 20 calculates the feedforward amounts FF1, FF2, FF3, FF2b, and FF3b using the inlet temperature Tin, the estimated temperature PV1h, the estimated temperature PV2h, the target temperature SV1, the target temperature SV2, and the target temperature SV3 using the first feedforward control unit 23a, the second feedforward control unit 23b, and the third feedforward control unit 23c. The algorithm for calculating the feedforward amounts FF1, FF2, FF3, FF2b, and FF3b is as described above.

[0048] The controller 20 determines whether the absolute value of the difference between the target temperature SV and the outlet temperature PV3 of the fluid is less than the temperature threshold δ (step ST16). The temperature threshold is the target temperature SV. When |SV - PV3| < δ holds (Yes in step ST16), the controller 20 proceeds to step ST17. When |SV - PV3| < δ does not hold (No in step ST16), the controller 20 proceeds to step ST20.

[0049] When |SV - PV3| < δ holds (Yes in step ST16), the controller 20 makes a determination comparing the required power P with the first threshold α and the second threshold β (α < β). When 0 ≦ P ≦ α holds, the controller 20 proceeds to step ST18. When α < P ≦ β holds, the controller 20 proceeds to step ST19. When β < P holds, the controller 20 proceeds to step ST20.

[0050] The first threshold α is the required power with which temperature control can be achieved by one heating / cooling unit 4. The second threshold β is the required power with which temperature control is insufficient by one heating / cooling unit 4 and temperature control can be achieved by two heating / cooling units 4.

[0051] When 0 ≦ P ≦ α holds, the controller 20 sets the manipulated variables MV1 and MV2 to fixed values, and the manipulated variable MV3 is calculated by adding the feedback amount FB3 and the feedforward amount FF3b (step ST18).

[0052] When α < P ≦ β holds, the controller 20 sets the manipulated variable MV1 to a fixed value, the manipulated variable MV2 is calculated by adding the feedback amount FB2 and the feedforward amount FF2b, and the manipulated variable MV3 is calculated by adding the feedback amount FB3 and the feedforward amount FF3 (step ST19).

[0053] When δ does not hold or when β < P holds, the controller 20 calculates the manipulated variable MV1 by adding the feedback amount FB1 and the feedforward amount FF1, calculates the manipulated variable MV2 by adding the feedback amount FB2 and the feedforward amount FF2, and calculates the manipulated variable MV3 by adding the feedback amount FB3 and the feedforward amount FF3 (step ST20).

[0054] FIG. 7 is a diagram showing the controllability of the outlet temperature with respect to fluctuations in the inlet temperature of the fluid. FIG. 8 is a diagram showing the behavior of the manipulated variable. FIG. 7 shows the simulation results comparing the amount of change in the outlet temperature PV3 with respect to the change in the inlet temperature Tin when the outputs of the two heating / cooling units are fixed as shown in FIG. 5 and when the outputs of the three heating / cooling units are not fixed as shown in FIG. 2. As shown in FIG. 7, when the outputs of the two heating / cooling units are fixed, the amount of change in the outlet temperature PV3 with respect to the change in the inlet temperature Tin is about 1 / 3 compared to the case where the outputs of the three heating / cooling units are not fixed.

[0055] FIG. 8 shows, for reference, the simulation results comparing the manipulated variables when the outputs of the two heating / cooling units are fixed as shown in FIG. 5 and when the outputs of the three heating / cooling units are not fixed as shown in FIG. 2.

[0056] <Effect> As described above, in the embodiment, after the start of operation and until the outlet temperature of the fluid reaches the target temperature, the fluid is temperature-controlled by performing feedforward control and feedback control on the heating / cooling unit 4. After the outlet temperature of the fluid reaches the target temperature, the output of one or more of the heating / cooling units is stopped or set to a fixed value according to the magnitude of the disturbance. According to the embodiment, it is possible to suppress the redundancy of the plurality of arranged heating / cooling units 4 according to the magnitude of the disturbance and suppress the degradation of the resolution of the entire heating / cooling unit 4.

[0057] In the embodiment, the output of one or more heating and cooling units 4 can be stopped or set to a fixed value depending on the inlet temperature Tin of the fluid and the flow rate Qs of the fluid added from the outside.

[0058] In an embodiment, the output of one or more heating and cooling units 4 can be stopped or set to a fixed value depending on the required power calculated based on the inlet temperature Tin of the fluid and the flow rate Qs of the fluid added from the outside.

[0059] Specifically, for example, if the resolution of each heating / cooling unit 4 is 1°C, the resolution of the entire heating / cooling units 4 may be 3°C depending on the conditions. If the temperature difference adjusted by the heating / cooling units 4 is 1°C, three heating / cooling units 4 may not be able to properly control the temperature. According to the embodiment, in such a case, the output of two heating / cooling units 4 can be stopped or set to a fixed value, and the temperature can be properly controlled using one heating / cooling unit 4.

[0060] In the embodiment, when the output of one or more heating and cooling units 4 is stopped or set to a fixed value, the output of the heating and cooling units 4 can be stopped or set to a fixed value in order from the most upstream unit.

[0061] In the embodiment, when the required power P is equal to or less than the first threshold value α, the operation amounts of the two heating and cooling units 4a and 4b are set to fixed values, and the operation amount of the one heating and cooling unit 4c can be calculated by the third feedforward control unit 23c.

[0062] In the embodiment, when the required power P is greater than the first threshold value α and less than or equal to the second threshold value β, the operation amount of one heating / cooling unit 4a is set to a fixed value, and the operation amounts of the two heating / cooling units 4b and 4c can be calculated by the second feedforward control unit 23b and the third feedforward control unit 23c.

[0063] In this embodiment, when the required power P is greater than the second threshold value β, the operation amounts of the three heating and cooling units 4a, 4b, and 4c can be calculated by feedback control.

[0064] Specifically, by setting the outputs of the two upstream heating and cooling units 4a and 4b to fixed values ​​MV1 and MV2, a transmission delay occurs as the signal passes through the two upstream units. According to this embodiment, the third feedforward control unit 23c can generate a compensation time allowance. According to this embodiment, fluctuations in the fluid inlet temperature Tin can be compensated for regardless of the responsiveness of the heating and cooling unit 4.

[0065] <Modification> In the above description, the inlet temperature sensor 12 and the outlet temperature sensor 13 are provided as temperature sensors, but a temperature sensor or temperature estimation means for measuring the outlet temperature PV3 of each heating and cooling unit 4 may also be provided.

[0066] Although the above description has been made on the case where the heating / cooling unit 4 heats a fluid, it is also applicable to the case where the heating / cooling unit 4 cools a fluid.

[0067] Although an example of three heating and cooling units has been shown above, four or more heating and cooling units may be provided. [Explanation of symbols]

[0068] 1...Temperature control device, 2...Tank, 3...Pump, 4...Heating / cooling unit, 4a...Heating / cooling unit, 4b...Heating / cooling unit, 4c...Heating / cooling unit, 10...Circulation flow path, 11...Flow rate sensor, 12...Inlet temperature sensor, 13...Outlet temperature sensor, 17...Supply port, 18...Return port, 19...Fluid addition port, 20...Controller, 21...SV distributor, 22a...First feedback control section, 22b...Second feedback control section, 22c...Third feedback control section, 23a...First feedforward control section, 23b...Second feedforward control section, 23c...Third feedforward control section, 100...External process Process device, 101...process, 102...valve, FB1...feedback amount, FB2...feedback amount, FB3...feedback amount, FF1...feedforward amount, FF2...feedforward amount, FF3...feedforward amount, MV1...operated amount, MV2...operated amount, MV3...operated amount, P...required power, PV1...outlet temperature, PV2...outlet temperature, PV3...outlet temperature, PV1h...estimated temperature, PV2h...estimated temperature, Q...supply amount, Qp...flow rate, Qr...flow rate, Qs...flow rate, SV...target temperature, SV1...target temperature, SV2...target temperature, SV3...target temperature, Tin...inlet temperature, α...first threshold, β...second threshold, δ...temperature threshold.

Claims

1. a circulation flow path through which a fluid flows; a plurality of heating and cooling units arranged in series in the circulation flow path, for heating or cooling the fluid flowing through the circulation flow path; a controller for controlling the heating and cooling unit; Equipped with the controller adjusts the temperature of the fluid by performing feedforward control and feedback control on the heating and cooling units after starting operation until the outlet temperature of the fluid reaches a target temperature, and after the outlet temperature of the fluid reaches the target temperature, stops the output of one or more of the heating and cooling units or sets the output to a fixed value depending on the magnitude of the disturbance; Temperature control device.

2. The disturbances are an inlet temperature, which is the temperature of the fluid flowing into the most upstream heating and cooling unit, and a flow rate of the fluid added from outside. The temperature control device according to claim 1 .

3. The disturbance is calculated as a required power based on an inlet temperature of the fluid and a flow rate of the fluid added from the outside. The temperature control device according to claim 2 .

4. When the controller stops or sets the output of one or more of the heating and cooling units to a fixed value, the controller stops or sets the output of the heating and cooling units to a fixed value in order from the most upstream. The temperature control device according to claim 1 .

5. Three of the heating and cooling units are connected in series, when the required power is equal to or less than a first threshold, the controller sets the operation amounts of the two heating and cooling units to fixed values, and calculates the operation amount of one of the heating and cooling units by feedback control and feedforward control. The temperature control device according to claim 3 .

6. Three of the heating and cooling units are connected in series, when the required power is greater than a first threshold and equal to or less than a second threshold, the controller sets an operation amount of one of the heating / cooling units to a fixed value, and calculates operation amounts of the two heating / cooling units by feedback control and feedforward control. The temperature control device according to claim 3 .

7. Three of the heating and cooling units are connected in series, When the required power is greater than a second threshold, the controller calculates the operation amounts of the three heating and cooling units by feedback control and feedforward control. The temperature control device according to claim 3 .

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