TW550365B - Wide-temperature-range constant-temperature refrigerating system and control method thereof - Google Patents

Abstract

This invention relates to a wide-temperature-range constant-temperature refrigerating system, comprising a refrigerating machine, a low-temperature heat exchanger, a medium-temperature heat exchanger, a high-temperature heat exchanger, a pump, a first solenoid valve, a second solenoid valve, a third solenoid valve, a temperature sensor, a power regulator, and a controller, wherein the temperature sensor is employed to set temperature of a working fluid and compare actual input temperature and actual output temperature of the working fluid with the set temperature, and the controller controls switching of ON/OFF states of the first solenoid valve, the second solenoid valve, and the third solenoid valve to control the working fluid flowing through different heat exchanger, to proceed heating or cooling to the working fluid, making the temperature of the working fluid approach the set temperature, so as to obtain the precise set temperature of the working fluid in low temperature range (-40 DEG C to 25 DEG C) or middle temperature range (25 DEG C to 50 DEG C) or high temperature range (50 DEG C to 100 DEG C) required for various industrial processes, and thereby having the efficacy of saving energy and maintaining normal operation of system.

Description

550365 V. Description of the invention (1) [Technical field to which the invention belongs] The present invention relates to a wide temperature range constant temperature freezing system and a control method thereof, and in particular, it can provide semiconductor, biochemical materials, food processing, raw materials and other industrial processes. Low temperature or medium temperature or high temperature constant temperature working fluid freezing system and method for controlling the freezing system. [Previous technology] Refrigeration equipment required for general processes usually uses a refrigerant compression freezer, which is automatically compensated with an electric heating device to achieve the dual function of heating or cooling, and makes the working fluid used in the process, such as coolant, antifreeze, brine Or use liquid mixture in the process to maintain accurate set temperature. _ As shown in the eighth figure, the conventional constant temperature refrigeration system 2 includes: a tank 20 having an input pipeline 27 and an output pipeline 28; a pump 2 6 connected in series to the aforementioned output pipeline 28; and placed in the aforementioned tank In 20, a plate heat exchanger 2 1 providing a cold source; a heater 2 2 provided in the aforementioned tank 20 to provide a heat source; connected in series to the aforementioned heat exchanger 2 1, by a condenser 2 3, an expansion valve 24 and compressor 25 constitute a refrigerator that provides a refrigerant circuit. The aforementioned input pipeline 27 is used to input the working fluid into the tank 20, and the aforementioned output pipeline 28 is used to output the working fluid with accurate temperature setting required for the manufacturing process. The conventional constant temperature refrigeration system 2 uses a set of cold sources for cooling function and a set of heat sources for temperature feedback compensation heating. Since the plate heat exchanger 2 1 providing the cold source and the heater 2 2 providing the heat source are placed in the same system In the tank body 20, this method does not cause abnormal operation of the compressor 25 for a small load type process or constant temperature control. However, for applications with large heat loads over a long period of time, the structure in which the cold source and the heat source are co-located in the same tank is easy to build.

Page 7 550365 V. Description of the invention (2) The compressor starts abnormally in high temperature mode. Furthermore, because refrigeration systems are usually designed for a certain low temperature range (for example,-40 ° C ~ 0 ° C), for applications above room temperature to high temperature (for example, 60 ° C ~ 100 t :), If the low-temperature refrigeration system is used to maintain the high-temperature cooling function, the temperature difference is too large, not only wasting electricity, but also causing considerable damage to the compressor's service life, especially for process equipment that operates 24 hours a day, and it will also cause Excessive waste of process energy. For example, the conventional refrigeration system 2 shown in the eighth figure has a refrigerant evaporation temperature of about -40 ° C to 0 ° C, but in a high-temperature operating environment, the refrigerant will return to the temperature of the compressor 25 to overheat. This overheating temperature is even as high as 70 ° C ~ 100 ° C, causing the refrigerant suction to enter the pipeline to reach a high pressure state, causing the refrigerant suction function of the compressor 25 to decay, and even unable to smoothly suck back to the compressor 25 cavity. System, causing the refrigeration system 2 to lose its balance and endanger the overall refrigeration system, resulting in the backwardness of production schedule and having a great impact. [Effect of the invention] The present invention considers that most of the process equipment environment provides factory water and its cooling equipment, such as ice water host, cooling water tower and other equipment. Its efficiency at room temperature is much greater than the evaporation temperature at- The freezer at 40 ° C, so for the wide temperature range process application of-40 ° C ~ + 100 ° C, the control method of the present invention can effectively achieve the purpose of constant temperature control and energy efficiency improvement, which makes the shortage The energy can be effectively used, and in addition, the freezer can be operated under the optimal operating conditions, thereby improving the service life. The low temperature (-40 ° C ~ 25 ° C), medium temperature (25 ° C ~ 50 ° C), and high temperature (50 ° C ~ 100 ° C) referred to in the present invention need not be clear Definition, but choose refrigerant and freezer according to user needs.

Page 8 550365 V. Description of the invention (3) [Summary of the invention] The main purpose of the present invention is to provide a wide temperature range constant temperature freezing system, which is a court service that will be equipped with general semiconductor, biochemical materials, food processing, raw materials and other process equipment Water (faci 1 itywater) and its cooling equipment, such as ice water main unit, cooling water tower, etc., cooperate with pipelines and several solenoid valves, and control different solenoid valves 0N or OFF according to different temperature requirements to provide the low temperature required for industrial processes (- 40 ° C ~ 2 5 ° C) or medium temperature (25 ° C ~ 50 ° C) or high temperature (50 ° C ~ 100 ° C) working fluid (w 〇rkingf 1) uid) to save energy and maintain the normal operation of the system. The wide temperature range constant temperature refrigeration system that achieves the above purpose includes a refrigerator, a low temperature heat exchanger, a medium temperature heat exchanger, a high temperature heat exchanger, a pump, a first solenoid valve, a second solenoid valve, and a third Solenoid valve, temperature sensor, power regulator and controller, the aforementioned refrigerator, low temperature heat exchanger, medium temperature heat exchanger, high temperature heat exchanger, pump, first solenoid valve, second solenoid valve, The third solenoid valve is connected through a pipeline and has an input end and an output end. The work flow system is inputted through the input end and driven by the pump and outputted by the output end. The power conditioner is for high-temperature heat exchange. The temperature sensor is used to set the output temperature of the working fluid, and the controller is used to control the opening and closing of the first solenoid valve, the second solenoid valve, and the third solenoid valve to control the flow of fluid through different heat sources. The exchanger is used for heating or cooling the working fluid, so that the temperature of the output working fluid approaches the set temperature to achieve constant temperature control. Preferably, the medium-temperature heat exchanger and the high-temperature heat exchanger are co-located in a tank body t and the tank system is provided at the input end, and the tank body, the pump, and the output

Page 9 550365 V. Description of the invention (4) The pipeline at the end is connected to the medium temperature heat exchange heat exchanger. Preferably, the pipeline is connected to the medium temperature heat exchange solenoid valve. Preferably, a medium temperature heat exchange solenoid valve is connected to the pipeline, and a magnetic valve is connected. Preferably, the liquid is used for the control method of the present invention. The fluid is actually transferred to the first electromagnet, and the precise setting of the output process (-4 0 OC to 2 5) is reached to reach the tube connected with the first electromagnetic converter in series. On the road, on the pipeline and in parallel with the first solenoid valve pipeline of the aforementioned South-Temperature Heat Exchanger and in parallel with the low-temperature heat exchanger, the high-temperature heat exchange is coupled with the first solenoid valve pipeline. It is also connected in parallel to the low temperature heat exchanger, a mixture of the aforementioned workflow systems. Another purpose is to provide a heat exchanger that sets the temperature, the actual output valve, the second solenoid valve, and the heat exchanger to set the cold temperature. The fluid temperature tends to be ° C) or medium temperature (25 ° C ~ working temperature.) For the wide temperature range constant valve described above, the second solenoid valve series is connected in series with the third solenoid valve series is connected in series with the first lower one. The solenoid valve and the pump system are provided at the output terminal, and the second solenoid valve system is connected in series to the first solenoid valve and the third pipeline and is connected in parallel to the first electrical appliance and the pump system at the input terminal. And, the aforementioned second electric The magnetic valve is connected in series with the first solenoid valve and the third pipeline and is connected in parallel with the first electric fluid as a coolant, non-fluid, culvert or a wide temperature range constant temperature refrigeration system. The temperature difference between the temperature and the set temperature 'cuts the opening and closing of the third solenoid valve to control the working fluid for heating or cooling. The set temperature' 俾 obtains a low temperature of 50 t :) or a high temperature (50 ° C ~ 100 ° C). Control method of refrigeration system

Page 10 550365 V. Description of the invention (5) Contains the following steps a. Set freezing b. Start the pump to the aforementioned Lengkang c. Use the temperature difference of the temperature sensed d. Heat the difference between the aforementioned temperature and e. A better source of temperature for heating or cooling makes the process energy efficient. It is better to use a cold source, which can be lowered. It is better to switch to a cold one. It is better to cool the freezing system to ensure the operation of the freezing system. The required working fluid temperature; the working fluid to the above-mentioned cold; the eastern system, and the input of the factory water differential signal exchanger. The low temperature can be reached, the middle temperature is lowered by 25 ° C, and the temperature system opens the sensor, and the aforementioned freezer system can be: The system input system; the detector compares the input temperature, output temperature and setting of the working fluid to the controller To control the opening and closing of the first, second, and third solenoid valves that flow through low, medium, and high temperatures; and the opening and closing of the second and third solenoid valves, the working fluid temperature to and from the working fluid tends to be set to the available The application is to use a refrigerator to take away the heat generated by the process in a cold and low temperature environment below 25 ° C, and to save the electricity consumed by the above temperature control by using the factory water of the application temperature higher than 25 ° C to save electricity. energy. The application uses a high-temperature heat exchanger. The high-temperature heat exchanger is permanently in the 0 N state, and is fine-tuned by the temperature difference signal of the power regulator to achieve an accurate constant working fluid temperature when the medium or high temperature is required. Cooling is controlled by intermittent on / off mode, and can be smoothly operated under a wide range of temperature conditions for a long time.

550365 V. Description of the invention (6) The foregoing objects or features of the present invention will be described in detail with reference to the drawings, but it must be understood that the drawings and examples are for illustration only and not for limitation or limitation. Limited edition. [Embodiment] The first specific embodiment of the wide temperature range constant temperature refrigeration system 10 according to the present invention is shown in the first figure. The cold health system 10 includes: a cold rolling machine R, a low temperature heat exchanger LHX, and a medium temperature heating system. Exchanger MHX, high-temperature heat exchanger HHX, pump P, first solenoid valve SV 1, second solenoid valve SV 2, third solenoid valve SV 3, temperature sensor TS1, power regulator SSR, and controller C . The aforementioned medium-temperature heat exchanger MHX and the high-temperature heat exchanger HHX are co-located in a tank body 11 and the tank body 11 is provided at the input terminal IN, the aforementioned tank body 1, the pump P, and the output terminal OUT. The first solenoid valve SV1 is connected in series to the pipeline, the second solenoid valve SV2 is connected in series to the pipeline of the medium temperature heat exchanger MHX, and the third solenoid valve SV3 is connected to the low temperature heat exchanger LHX pipeline and The first solenoid valve SV 1 is connected in parallel. The refrigerating machine R is connected in series with a low-temperature heat exchanger LHX °, and the power conditioner SSR is connected to the high-temperature heat exchanger Η Η X, an AC power source, and the controller C by a circuit, respectively. The temperature-controllable temperature sensor TS 1 is built in the controller C, and the controller C is connected to the aforementioned first electromagnetic valve SV1, the second electromagnetic valve SV2, and the aforementioned third electromagnetic valve SV 3 by a circuit, respectively. In addition, the temperature sensor TS 1 is connected to the input terminal IN and the output terminal OUT to detect the temperature T2 of the input terminal IN and the temperature T1 of the output terminal OUT. The related electrical connection lines are shown in dotted lines in the figure. The aforementioned power regulator SSR performs load regulation on the high-temperature heat exchanger HHX

Page 12 550365 V. Description of the invention (7), the aforementioned temperature sensor TS 1 is used to set the output temperature of the working fluid, and the aforementioned controller C is used to control the first solenoid valve SV 1 and the second solenoid valve s V 2. The third solenoid valve s V 3 is opened and closed to control fluid flow through different heat exchangers to heat or cool the working fluid. The working fluid, for example: coolant, antifreeze, brine or process liquid mixture, is input into the tank 11 via the aforementioned input terminal IN and driven by the aforementioned pump P, and is output by the first solenoid valve SV1 from the aforementioned output terminal OUT, and The third solenoid valve SV3 and the low-temperature heat exchanger LHX are output from the aforementioned output terminal OUT. Refrigerator R is a cold source that provides a low-temperature heat exchanger LHX 2 below 5 ° C; for example, factory water FW is ice water that is higher than room temperature 2 5 ° C, and then flows through the second heat exchanger SV 2 in series And medium-temperature heat exchanger M Η X, providing a medium-temperature cold source; the high-temperature heat exchanger XX is always in the ON state after the refrigeration system 10 is turned on, and the power regulator SSR refers to the temperature difference of the aforementioned temperature sensor TS 1 The signal is fine-tuned to provide temperature compensation. The control method of the wide temperature range constant temperature refrigeration system 10 according to the first embodiment will be described in detail below with reference to the first and seventh figures. First set the temperature of the working fluid required for the refrigeration system 10; then start the pump P to input the working fluid to the aforementioned cold; East System 10, and input the service water FW to the aforementioned refrigeration system 10, and then read the temperature sensing The set temperature of the device tsi (the set temperature is also set by TS 1 because the set temperature is set by the temperature sensor TS 1), the actual input temperature τ 2 of the working fluid and the actual output temperature T 1 of the working fluid, and compare three According to the comparison of the aforementioned set temperature TS1, the actual input temperature T2 of the working fluid and the actual output temperature τ1 temperature of the working fluid, the working fluid is heated or cooled.

Page 13 550365 V. Description of the invention (8) In more detail, when comparing the temperature of the set temperature TS1, the actual input temperature T2 of the working fluid and the actual output temperature T1 of the working fluid as described above, if T1 is greater than TS1 and greater than T2, The cooling mode is performed. At this time, it is still judged whether the difference between the output temperature T1 and the set temperature TS1 is less than the error value ε (assuming ± 0 · 1 ° C). If it is still greater than the error value ε, the cooling mode is continued; if it is less than The error value ε is changed to the heating mode, so that the output temperature T 1 of the working fluid tends to the set temperature TS 1 and is maintained at a constant temperature state of the error value. Please refer to the seventh figure. The other control modes for comparing the temperature of T 1, T S 1 and T 2 are not described in detail.

The above cooling mode and heating mode will be further described below with reference to the fourth and sixth figures, and please cooperate with the first figure.

As shown in the fourth figure, when the input working fluid is cooled, the set temperature TS 1 is first checked. When the refrigeration system 10 is a low temperature application, the controller C controls the first solenoid valve SV 1 to be 0FF, and the second The solenoid valve SV 2 is 0 FF, the third solenoid valve SV3 is 0N, and the high-temperature heat exchanger XX is 0N. The working fluid flows into the tank 11 from the input terminal IN, and then flows through the pipeline through the third solenoid valve sv 3 After passing through the low-temperature heat exchanger LHX, it finally flows out from the output end. When the refrigeration system 10 is used at medium or high temperature, the controller C controls the first solenoid valve s V 1 to be ON and the second solenoid valve SV 2 to be OFF, the third solenoid valve SV3 is off and the high-temperature heat exchanger Η Η X is 0N, the working fluid flows from the input terminal 丨 n into the tank 11, and then passes through the pipeline through the first solenoid valve SV1, and finally outputs Terminal υυτ flows out. As shown in the sixth figure, when the input working fluid is heated, whether the refrigeration system 10 is low temperature, medium temperature or high temperature, the controller C controls the first solenoid valve SV 1 to 0 N and the second solenoid The valve sv 2 is 0 ° F, the third electromagnetic 550365. 5. Description of the invention (9) The valve SV3 is OFF and the high-temperature heat exchanger HHX is 0N. The working fluid flows into the tank 11 from the input terminal IN and receives high-temperature heat. The heat of the exchanger HHX is passed through the pipeline through the first electromagnetic 阙 SV 1 and finally flows out from the output terminal υ τ. The second embodiment of the wide temperature range constant temperature refrigeration system 10 of the present invention is shown in the second figure, which mainly includes: a refrigerator R, a low-temperature heat exchanger LHX, a medium-temperature heat exchanger MHX, and a high-temperature heat exchanger HHX. Pump P, first solenoid valve SV1, second solenoid valve SV2, and third solenoid valve SV3. The power regulator, temperature sensor and controller in the second figure are omitted because the circuit connection methods are the same as in the first figure. In the second figure, the high-temperature heat exchanger Η Η X and the pump P are provided at the output end, and the pipeline is connected in series with the first solenoid valve S V1, and the second solenoid valve is connected in series with the medium-temperature heat exchanger M Η The X line is connected in parallel to the first solenoid valve SV 1, and the third solenoid valve SV 3 is connected in series to the low temperature heat exchanger L Η X line and is connected in parallel to the first solenoid valve SV 1. Regarding the wide temperature range constant temperature freezing system 10 of the second specific embodiment shown in the second figure, the control method is also shown in the seventh figure. For the related control method, please refer to the relevant description of the first specific embodiment. Do not go into details. However, the cooling mode and heating mode of the second specific embodiment will be further described below in conjunction with the fifth and sixth figures, and please cooperate with the second figure. As shown in the fifth figure, when cooling the input working fluid, first check the set temperature TS 1 '. When the refrigeration system is low temperature, the controller C controls the first solenoid valve SV1 to be OFF, and the second solenoid valve SV2 is OFF, the second solenoid valve SV3 is 0N, and the high-temperature heat exchanger ΗΗχ is ⑽. The working fluid flows in from the input terminal I Ν, and then flows through the pipeline through the third solenoid valve SV3 and passes through the low-temperature heat exchange.

Page 15 550365 V. Description of the invention (ίο) The device L Η X and flow through the high temperature heat exchanger η Η X, and finally flow out from the output terminal OUT; when the refrigeration system 10 is used at medium or high temperature, it is determined by The controller C controls the first solenoid valve SV1 to be OFF, the second solenoid valve SV2 to be ON, the third solenoid valve SV3 to be OFF, and the high-temperature heat exchanger HHX to be 0N. The working fluid flows from the input terminal IN, and then flows through the pipeline. The second solenoid valve SV2 flows through the medium-temperature heat exchanger MHX and the high-temperature heat exchanger HHX, and finally flows out from the output terminal OUT. As shown in the sixth figure, when the input working fluid is heated, whether the refrigeration system 10 is low temperature, medium temperature or high temperature, the controller C controls the first solenoid valve SV1 to be ON, and the second solenoid valve SV2 Is OFF, the third solenoid valve SV 3 is OFF, and the high-temperature heat exchanger HHX is ON. The working fluid flows from the input terminal _ IN, flows through the pipeline through the first solenoid valve SV 1, and then flows through the high-temperature heat exchanger HHX. Finally, it flows out from the output terminal OUT. The third specific embodiment of the wide temperature range constant temperature refrigeration system 10 according to the present invention is shown in FIG. 3. The pump P and the high-temperature heat exchanger- 乂 are arranged at the input end IN of the working fluid and are different from the second specific embodiment. Except for the embodiment, the rest are the same as the second specific embodiment. The control method of the wide temperature range constant temperature freezing system 10 according to the third embodiment is also the same as that of the first embodiment, and will not be described again. However, the cooling mode and heating mode of the third specific embodiment will be further explained below with reference to the fifth and sixth figures, and please cooperate with the third figure. As shown in the fifth figure, when the input working fluid is cooled, first check the set temperature τ S 1. When the refrigeration system 10 is a low temperature application, the controller C controls the first solenoid valve sVI to be OFF, and the second The solenoid valve SV2 is OFF, the third solenoid valve SV 3 is 0 N, and the high-temperature heat exchanger Η Η X is 0 N, and the working fluid is automatically transported.

Page 16 550365 V. Description of the invention (11) Into stand and I Ν λπ »into, the shield pipe is changed to 'H [JX and flow through the: r solenoid valve SV 3 and then flow through low temperature The heat exchanger L Η X 'Dare to flow from the wheel outlet q υ τ; when the cold beam system 10 is used at medium or south temperature', the control valve C controls the first solenoid valve SV1 to be OFF and the second The solenoid valve SV2 is ON, the third solenoid valve sv3 is OFF, and the high-temperature heat exchanger HHX is 0N. The working fluid flows from the input IN into the pipeline through the high-temperature heat exchanger Η Η X and flows through the second solenoid The valve μ 2 passes through the medium-temperature heat exchanger MXX, and finally flows out from the output terminal OUT. As shown in the sixth figure, when the input working fluid is heated, whether the cold beam system 10 is low temperature, medium temperature or high temperature, the controller C controls the first solenoid valve SV 1 to 0 N and the second The solenoid valve s V 2 is 0 FF, the third solenoid valve SV 3 is 0 FF, and the high-temperature heat exchanger Η Η X is 0N. The working fluid flows from the input IN, and flows through the pipeline through the high-temperature heat exchanger ΗHX and then flows. After passing through the first solenoid valve SV1, it finally flows out from the output terminal OUT. In the foregoing embodiments, the high-temperature heat exchanger HHX is a heater, which is always in a state of 0 N after the cooling system 10 is turned on, and is automatically adjusted by the power regulator according to temperature changes. When the working fluid temperature requirement in the foregoing embodiments is medium or high temperature, the refrigerator R of the refrigeration system 10 is controlled to operate in an intermittent on / off mode to ensure that the refrigeration system 10 can be used in a wide range of temperature conditions for a long time. It can run smoothly.

Page 17 550365 Schematic description [Schematic wide temperature range, wide temperature range, wide temperature range, wide temperature range, pattern mode, cooling mode, number one, [main 10, simple figure two figures, constant temperature three figures, constant temperature four Figure 5 shows the application of the third diagram, the sixth diagram, the seventh diagram, and the eight diagram of the element LHX, MHX, HHX, P, SV1, and SV2. [Description] This is a configuration diagram of the refrigeration system of the first embodiment controlled by the control method of the present invention. It is a configuration diagram of the refrigeration system of the second specific embodiment controlled by the control method of the present invention. It is a configuration diagram of the refrigeration system of the third embodiment controlled by the control method of the present invention. It is a flow chart of the cooling mode of the control method of the present invention. This cooling is shown in the first embodiment shown in the first figure. It is a flowchart of another cooling mode of the control method of the present invention, which is applied to the second embodiment and the third embodiment shown in the second figure. It is a flowchart of the heating mode of the control method of the present invention. It is a flowchart of the control method of the present invention. Department of the conventional constant temperature refrigeration system configuration diagram. Explanation of reference symbols] Wide temperature range constant temperature refrigeration system Freezer Low temperature heat exchanger Medium temperature heat exchanger Medium temperature heat exchanger Pump First solenoid valve Second solenoid valve

Page 18 550365 Brief description of the diagram SV3… The first, a solenoid valve TS1… temperature sensor T1… out α temperature T2… inlet temperature FW… factory water SSR… power controller C… controller

Claims (1)

550365 The input regulator is the first fluid control system, the temperature control temperature domain converter body, the second and third electric power input end power sensing system control control or cold to constant wide wide description slot The parallel warp device is used for a current passing to make the transmission constant temperature system common pump electromagnetic solenoid valve magnetic valve constant temperature outlet valve system valve and the temperature zone on the second electromagnetic first electromagnetic circuit and the patent application scope 1. A wide temperature range constant temperature refrigeration system, a converter, a medium temperature heat exchanger, a high temperature valve, a second solenoid valve, a third solenoid and a controller, the aforementioned refrigerator, heat exchanger, high temperature heat exchanger, pump, The three solenoid valves are connected through the pipeline, the work flow system is output from the aforementioned output through the aforementioned input, the aforementioned device performs load adjustment, the aforementioned output temperature of the temperature, and the controller solenoid valve and the third solenoid valve are opened and closed. The heating temperature of the working fluid tends to the set temperature to reach 2. As described in item 1 of the scope of the patent application, the above-mentioned medium-temperature heating father and the south temperature are changed, and the tank system is set at the input end. 'The first road is connected in series with the first solenoid valve, the pipeline of the heat exchanger, and the pipeline of the front heat exchanger and is connected in parallel with the top 3. The high-temperature heat exchanger and the heat exchanger described in item 1 of the scope of patent application. The pump is connected in series with the first solenoid valve, and the exchanger pipeline is connected in parallel with the valve system in series with the low-temperature heat exchanger. Sensor, power regulating low temperature heat exchanger, medium temperature heat exchange first solenoid valve, second solenoid valve, and having an input end and an output, the aforementioned pump drive sets a working fluid magnetic valve for high temperature heat exchange, and a second The working fluid refrigeration system with different heat exchanges, which is placed in a tank and the output end, is connected in series to the middle system and connected to the low temperature and cold; the east system, and its pipeline is connected in series to the warm temperature The aforementioned third electromagnetic Page 20 550365 6. Scope of patent application Valve. 4. The wide temperature range constant temperature refrigeration system described in item 1 of the scope of the patent application, wherein the high temperature heat exchanger and the pump system are provided at the input end, and the pipeline is connected in series with the first electromagnetic valve and the second electromagnetic valve. The valve system is connected in series to the medium-temperature heat exchanger pipeline and is connected in parallel to the first solenoid valve and the third solenoid valve are connected in series to the low-temperature heat exchanger pipeline and is connected in parallel to the first solenoid valve. 5. The wide temperature range constant temperature refrigeration system as described in item 1 of the scope of the patent application, wherein the aforementioned work flow system is a coolant, an antifreeze, brine, or a liquid mixture for a process. 6. The wide temperature range constant temperature refrigeration system as described in item 1 of the scope of patent application, wherein the aforementioned medium temperature heat exchanger is supplied with factory water. 7. The wide temperature range constant temperature refrigeration system as described in item 1 of the scope of patent application, wherein the high temperature heat exchanger is a heater. 8. A method for controlling a wide temperature range constant temperature refrigeration system, including the following steps: a. Set the temperature of the working fluid required by the refrigeration system; b. Start the pump to input the working fluid to the aforementioned cold beam system, and input the factory water to The aforementioned cold; East system; c. Comparing the temperature difference between the input temperature, the output temperature, and the set temperature of the working fluid with a temperature sensor; d. Sending the aforementioned temperature difference signal to the controller to control the different heat flowing through low, medium and high temperatures Opening and closing of the first, second and third solenoid valves of the exchanger; and Page 21 550365 6. Scope of patent application e. According to the opening and closing of the aforementioned first, second, and third solenoid valves, the working fluid is heated or cooled, so that the temperature of the output working fluid approaches the temperature set for use in the process. . 9. The control method of the wide temperature range constant temperature refrigeration system as described in item 8 of the scope of patent application, wherein the low temperature application is to use a refrigerator to provide a cooling source below 25 ° C. 10. The control method of the wide temperature range constant temperature refrigeration system as described in item 8 of the scope of patent application, wherein the medium temperature application is to use factory water with a temperature higher than 25 ° C as a cold source. 11. The control method of the wide temperature range constant temperature refrigerating system as described in item 8 of the scope of the patent application, where the South temperature application system is replaced by the South temperature heat father to 'The South temperature heat exchanger is always 0 N after the refrigeration system is turned on. State, and fine-tuned by the temperature difference signal of the power regulator's reference temperature sensor to achieve accurate constant temperature control. 1 2. The control method of the wide temperature range constant temperature refrigeration system as described in item 8 of the scope of the patent application, wherein when the temperature of the working fluid is medium or high, the refrigerator of the refrigeration system is controlled to operate in intermittent on / off mode. 0 Page 22