Condensing pressure control method and device for environmental test chamber and environmental test chamber

Abstract

The embodiment of the present application discloses a condensing pressure control method and device of an environmental test chamber and the environmental test chamber. The environmental test chamber comprises a chamber body, a control system, a refrigeration system and a water circuit system. The refrigeration system is located in the interior of the chamber body. The control system comprises a controller and a temperature sensor. The refrigeration system comprises a compressor, a condenser, an evaporator and a throttling element. The water circuit system comprises an electric ball valve, a water outlet pipeline and a water inlet pipeline. The condensing pressure control method is executed by the controller. The condensing pressure control method comprises the following steps: obtaining the real-time water inlet temperature, the real-time water outlet temperature and the real-time liquid outlet temperature of the condenser; determining the water side temperature difference and the refrigerant temperature difference of the condenser according to the real-time water inlet temperature, the real-time water outlet temperature and the real-time liquid outlet temperature; and controlling the opening degree of the electric ball valve according to the water side temperature difference and the refrigerant temperature difference, so as to control the condensing pressure of the environmental test chamber. The technical scheme of the environmental test chamber provided by the embodiment of the present application can guarantee the control reliability.

Description

Technical Field

[0001] The embodiments of the present invention relate to test chamber control technology, and more particularly to a method, device and environmental test chamber for controlling the condensation pressure of an environmental test chamber. Background Technology

[0002] Environmental test chambers can perform temperature and humidity tests. Products or equipment requiring temperature and humidity testing are typically tested in environmental test chambers. To meet the testing requirements of products or equipment, the temperature and humidity in the environmental test chamber must be controllable, and the condensation pressure must also be controllable to ensure practical application requirements.

[0003] Currently, the existing methods for controlling the condensation pressure of environmental test chambers usually involve directly adjusting the pressure regulating valve. However, the pressure regulating valve suffers from lag and a small adjustment range, which affects the reliability of the control. Summary of the Invention

[0004] This invention provides a method, apparatus, and environmental test chamber for controlling the condensation pressure of an environmental test chamber, thereby ensuring control reliability.

[0005] In a first aspect, embodiments of the present invention provide a method for controlling the condensing pressure of an environmental test chamber. The environmental test chamber includes a chamber body, a control system, a refrigeration system, and a water system. The refrigeration system is located inside the chamber body. The control system includes a controller and a temperature sensor. The refrigeration system includes a compressor, a condenser, an evaporator, and a throttling element. The water system includes an electric ball valve, an outlet pipe, and an inlet pipe. The outlet of the compressor is connected to the liquid inlet of the condenser, the outlet of the condenser is connected to the inlet of the evaporator, and the outlet of the evaporator is connected to the inlet of the compressor. The throttling element is installed in the pipe connecting the condenser and the evaporator. The temperature sensor is installed on the side of the outlet pipe and the inlet pipe near the condenser. The electric ball valve is located in the outlet pipe. The outlet of the condenser is connected to the outlet pipe, and the inlet of the condenser is connected to the inlet pipe. The temperature sensor, the compressor, the throttling element, the electric ball valve, and the controller are electrically connected. The condensing pressure control method is executed by the controller and includes:

[0006] The real-time inlet water temperature, real-time outlet water temperature, and real-time outlet liquid temperature of the condenser are obtained.

[0007] The water-side temperature difference and refrigerant temperature difference of the condenser are determined based on the real-time inlet water temperature, the real-time outlet water temperature, and the real-time outlet liquid temperature.

[0008] The opening degree of the electric ball valve is controlled based on the water-side temperature difference and the refrigerant temperature difference to control the condensation pressure of the environmental test chamber.

[0009] Optionally, determining the water-side temperature difference and refrigerant temperature difference of the condenser based on the real-time inlet water temperature, the real-time outlet water temperature, and the real-time outlet liquid temperature includes:

[0010] The difference between the real-time outlet water temperature and the real-time inlet water temperature is taken as the water-side temperature difference;

[0011] The difference between the target outlet temperature and the real-time outlet temperature is taken as the refrigerant temperature difference.

[0012] Optionally, controlling the opening degree of the electric ball valve based on the water-side temperature difference and the refrigerant temperature difference includes:

[0013] When the refrigerant temperature difference remains constant and the water-side temperature difference increases, the opening degree of the electric ball valve is controlled to increase or remain constant.

[0014] When the water-side temperature difference remains constant and the refrigerant temperature difference increases, the opening degree of the electric ball valve is reduced.

[0015] Optionally, controlling the opening degree of the electric ball valve based on the water-side temperature difference and the refrigerant temperature difference includes:

[0016] When the refrigerant temperature difference is less than zero, the opening degree of the electric ball valve is increased.

[0017] When the refrigerant temperature difference is greater than zero, the opening degree of the electric ball valve is reduced.

[0018] Optionally, controlling the opening degree of the electric ball valve based on the water-side temperature difference and the refrigerant temperature difference includes:

[0019] When the refrigerant temperature difference is less than zero and the water-side temperature difference remains unchanged, the opening degree of the electric ball valve is increased, and the required increase in the opening degree of the electric ball valve decreases as the refrigerant temperature difference increases.

[0020] When the refrigerant temperature difference is greater than zero and the water-side temperature difference remains unchanged, the opening degree of the electric ball valve is reduced, and the required reduction in the opening degree of the electric ball valve increases with the increase of the refrigerant temperature difference.

[0021] When the refrigerant temperature difference is less than zero and the refrigerant temperature difference remains unchanged, the opening degree of the electric ball valve is increased, and the required increase in the opening degree of the electric ball valve increases with the increase in the water-side temperature difference.

[0022] When the refrigerant temperature difference is greater than zero and the refrigerant temperature difference remains constant, the opening degree of the electric ball valve is reduced, and the required reduction in the opening degree of the electric ball valve decreases as the water-side temperature difference increases.

[0023] Optionally, controlling the opening degree of the electric ball valve based on the water-side temperature difference and the refrigerant temperature difference includes:

[0024] When the water temperature is lower than a preset low temperature threshold, the opening degree of the electric ball valve is controlled to a preset large opening degree.

[0025] When the water temperature is higher than a preset high temperature threshold, the opening degree of the electric ball valve is controlled to a preset small opening degree.

[0026] Optionally, after obtaining the real-time inlet water temperature, real-time outlet water temperature, and real-time outlet liquid temperature of the condenser, the method further includes:

[0027] The initial opening degree of the electric ball valve is determined based on the real-time inlet water temperature.

[0028] Secondly, embodiments of the present invention provide a condensation pressure control device for an environmental test chamber. The environmental test chamber includes a chamber body, a control system, a refrigeration system, and a water system. The refrigeration system is located inside the chamber body. The control system includes a controller and a temperature sensor. The refrigeration system includes a compressor, a condenser, an evaporator, and a throttling element. The water system includes an electric ball valve, an outlet pipe, and an inlet pipe. The outlet of the compressor is connected to the liquid inlet of the condenser, the outlet of the condenser is connected to the inlet of the evaporator, and the outlet of the evaporator is connected to the inlet of the compressor. The throttling element is installed in the pipe connecting the condenser and the evaporator. The temperature sensor is installed on the side of the outlet pipe and the inlet pipe near the condenser. The electric ball valve is located in the outlet pipe. The outlet of the condenser is connected to the outlet pipe, and the inlet of the condenser is connected to the inlet pipe. The temperature sensor, the compressor, the throttling element, the electric ball valve, and the controller are electrically connected.

[0029] The condensation pressure control device includes:

[0030] The temperature acquisition module is used to acquire the real-time inlet water temperature, real-time outlet water temperature and real-time outlet liquid temperature of the condenser.

[0031] The temperature difference determination module is used to determine the water-side temperature difference and refrigerant temperature difference of the condenser based on the real-time inlet water temperature, the real-time outlet water temperature, and the real-time outlet liquid temperature.

[0032] The opening control module is used to control the opening degree of the electric ball valve according to the water-side temperature difference and the refrigerant temperature difference, so as to control the condensing pressure of the environmental test chamber.

[0033] Thirdly, embodiments of the present invention provide an environmental test chamber, comprising: a chamber body, a control system, a refrigeration system, and a water system. The refrigeration system is located inside the chamber body. The control system includes a controller and a temperature sensor. The refrigeration system includes a compressor, a condenser, an evaporator, and a throttling element. The water system includes an electric ball valve, an outlet pipe, and an inlet pipe. The outlet of the compressor is connected to the liquid inlet of the condenser, the outlet of the condenser is connected to the inlet of the evaporator, and the outlet of the evaporator is connected to the inlet of the compressor. The throttling element is installed in the pipe connecting the condenser and the evaporator. The temperature sensor is installed on the side of the outlet pipe and the inlet pipe near the condenser. The electric ball valve is located in the outlet pipe. The outlet of the condenser is connected to the outlet pipe, and the inlet of the condenser is connected to the inlet pipe. The temperature sensor, the compressor, the throttling element, the electric ball valve, and the controller are electrically connected. The condensing pressure control device as described in the second aspect is integrated into the controller.

[0034] Optionally, a water pressure gauge is installed in both the water inlet pipe and the water outlet pipe, and a water pressure protector is also installed in the water inlet pipe.

[0035] The present invention provides a method, apparatus, and environmental test chamber for controlling the condensing pressure of an environmental test chamber. The environmental test chamber includes a chamber body, a control system, a refrigeration system, and a water system. The refrigeration system is located inside the chamber body. The control system includes a controller and a temperature sensor. The refrigeration system includes a compressor, a condenser, an evaporator, and a throttling element. The water system includes an electric ball valve, an outlet pipe, and an inlet pipe. The compressor outlet is connected to the condenser inlet, the condenser outlet is connected to the evaporator inlet, and the evaporator outlet is connected to the compressor inlet. A throttling element is installed in the pipe connecting the condenser and the evaporator. The outlet pipe and the inlet pipe are located near... A temperature sensor is installed on the side near the condenser. An electric ball valve is located on the outlet water pipe. The condenser outlet is connected to the outlet water pipe, and the condenser inlet is connected to the inlet water pipe. The temperature sensor, compressor, throttling element, electric ball valve, and controller are electrically connected. The condensing pressure control method is executed by the controller and includes: acquiring the real-time inlet water temperature, real-time outlet water temperature, and real-time outlet liquid temperature of the condenser; determining the water-side temperature difference and refrigerant temperature difference of the condenser based on the real-time inlet water temperature, real-time outlet water temperature, and real-time outlet liquid temperature; and controlling the opening degree of the electric ball valve based on the water-side temperature difference and refrigerant temperature difference to control the condensing pressure of the environmental test chamber. The condensing pressure control method, device, and environmental test chamber provided by this invention control the opening degree of the electric ball valve in real time according to the determined water-side temperature difference and refrigerant temperature difference, thereby controlling the condensing pressure of the environmental test chamber. This solves the problems of hysteresis and small adjustment range of pressure regulating valves in the prior art, thus ensuring control reliability. Attached Figure Description

[0036] Figure 1 This is a flowchart of a condensation pressure control method for an environmental test chamber provided in Embodiment 1 of the present invention;

[0037] Figure 2 This is a flowchart of a condensation pressure control method for an environmental test chamber provided in Embodiment 2 of the present invention;

[0038] Figure 3 This is a structural block diagram of a condensation pressure control device for an environmental test chamber provided in Embodiment 3 of the present invention;

[0039] Figure 4 This is a schematic diagram of a partial structure of an environmental test chamber provided in Embodiment 4 of the present invention. Detailed Implementation

[0040] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0041] Example 1

[0042] Figure 1 This is a flowchart of a condensation pressure control method for an environmental test chamber according to Embodiment 1 of the present invention. This embodiment is applicable to condensation pressure control in environmental test chambers. The environmental test chamber includes a chamber body, a control system, a refrigeration system, and a water system. The refrigeration system is located inside the chamber body. The control system includes a controller and a temperature sensor. The refrigeration system includes a compressor, a condenser, an evaporator, and a throttling element. The water system includes an electric ball valve, an outlet pipe, and an inlet pipe. The compressor outlet is connected to the condenser inlet, the condenser outlet is connected to the evaporator inlet, and the evaporator outlet is connected to the compressor inlet. A throttling element is installed in the pipe connecting the condenser and the evaporator. A temperature sensor is installed on the side of the outlet and inlet pipes near the condenser. The electric ball valve is located in the outlet pipe. The condenser outlet is connected to the outlet pipe, and the condenser inlet is connected to the inlet pipe. The temperature sensor, compressor, throttling element, electric ball valve, and controller are electrically connected. This condensation pressure control method is executed by the controller, which can be implemented in software and / or hardware. The condensation pressure control method specifically includes the following steps:

[0043] Step 110: Obtain the real-time inlet water temperature, real-time outlet water temperature, and real-time outlet liquid temperature of the condenser.

[0044] Temperature sensors are installed at the inlet, outlet, and liquid outlet of the condenser. The controller is electrically connected to each temperature sensor to obtain the real-time inlet water temperature, real-time outlet water temperature, and real-time liquid outlet temperature of the condenser.

[0045] In addition, when the refrigeration system is started, the initial opening degree of the electric ball valve is determined based on the real-time inlet water temperature of the condenser. For example, when the refrigeration system is started, if the real-time inlet water temperature of the condenser is greater than 18 degrees Celsius, the initial opening degree of the electric ball valve is 60%; if the real-time inlet water temperature of the condenser is between 12 and 18 degrees Celsius, the initial opening degree of the electric ball valve is 40%; and if the real-time inlet water temperature of the condenser is less than 12 degrees Celsius, the initial opening degree of the electric ball valve is 25%.

[0046] It should be noted that the initial opening degree of the electric ball valve at different inlet water temperatures is only illustrative and should be determined based on the actual performance parameters of the refrigeration system and water circuit system, and is not limited here.

[0047] Step 120: Determine the water-side temperature difference and refrigerant temperature difference of the condenser based on the real-time inlet water temperature, real-time outlet water temperature, and real-time outlet liquid temperature.

[0048] The water-side temperature difference of the condenser is the difference between the outlet water temperature and the inlet water temperature. For example, the current water-side temperature difference of the condenser is the difference between the current outlet water temperature and the current inlet water temperature. The refrigerant temperature difference of the condenser is the difference between the target outlet liquid temperature and the actual outlet liquid temperature. For example, the current refrigerant temperature difference of the condenser is the difference between the target outlet liquid temperature and the current outlet liquid temperature. For instance, the target outlet liquid temperature is 30 degrees Celsius.

[0049] Step 130: Control the opening degree of the electric ball valve according to the water-side temperature difference and the refrigerant temperature difference to control the condensation pressure of the environmental test chamber.

[0050] Specifically, when the refrigerant temperature difference is less than zero and the water-side temperature difference remains constant (within a certain range), the opening degree of the electric ball valve is increased, and the required increase in opening degree decreases as the refrigerant temperature difference increases; when the refrigerant temperature difference is greater than zero and the water-side temperature difference remains constant, the opening degree of the electric ball valve is decreased, and the required decrease in opening degree increases as the refrigerant temperature difference increases; when the refrigerant temperature difference is less than zero and the refrigerant temperature difference remains constant, the opening degree of the electric ball valve is increased, and the required increase in opening degree increases as the water-side temperature difference increases; when the refrigerant temperature difference is greater than zero and the refrigerant temperature difference remains constant, the opening degree of the electric ball valve is decreased, and the required decrease in opening degree decreases as the water-side temperature difference increases. For example, when the water-side temperature difference is between 2 and 3 degrees Celsius, if the refrigerant temperature difference is between -3 and -2 degrees Celsius, the opening of the electric ball valve is increased by 4%; if the refrigerant temperature difference is between -2 and -1 degrees Celsius, the opening of the electric ball valve is increased by 2%; if the refrigerant temperature difference is between 1 and 2 degrees Celsius, the opening of the electric ball valve is decreased by 6%; and if the refrigerant temperature difference is greater than 2 degrees Celsius, the opening of the electric ball valve is decreased by 8%. When the refrigerant temperature difference is between -2 and -1 degrees Celsius, if the water-side temperature difference is between 2 and 3 degrees Celsius, the opening of the electric ball valve is increased by 2%; and if the water-side temperature difference is between 3 and 5 degrees Celsius, the opening of the electric ball valve is increased by 4%. When the refrigerant temperature difference is between 1 and 2 degrees Celsius, if the water temperature difference is between 2 and 3 degrees Celsius, the opening of the electric ball valve is reduced by 6%; if the water temperature difference is between 3 and 5 degrees Celsius, the opening of the electric ball valve is reduced by 4%.

[0051] It should be noted that the values ​​for increasing or decreasing the opening of the electric ball valve according to the changes in refrigerant temperature difference and water side temperature are only illustrative. The specific values ​​should be determined according to the actual working requirements of the refrigeration system and water circuit system, and are not limited here.

[0052] The condensing pressure control method for an environmental test chamber provided in this embodiment includes: acquiring the real-time inlet water temperature, real-time outlet water temperature, and real-time outlet liquid temperature of the condenser; determining the water-side temperature difference and refrigerant temperature difference of the condenser based on the real-time inlet water temperature, real-time outlet water temperature, and real-time outlet liquid temperature; and controlling the opening degree of the electric ball valve based on the water-side temperature difference and refrigerant temperature difference to control the condensing pressure of the environmental test chamber. This method for controlling the condensing pressure of an environmental test chamber, by controlling the opening degree of the electric ball valve to increase or decrease in real time based on the determined water-side temperature difference and refrigerant temperature difference, solves the problems of hysteresis and small adjustment range of pressure regulating valves in the prior art, thereby ensuring control reliability.

[0053] Example 2

[0054] Figure 2 This is a flowchart of a condensation pressure control method for an environmental test chamber according to Embodiment 2 of the present invention. This embodiment is applicable to condensation pressure control in environmental test chambers. The environmental test chamber includes a chamber body, a control system, a refrigeration system, and a water system. The refrigeration system is located inside the chamber body. The control system includes a controller and a temperature sensor. The refrigeration system includes a compressor, a condenser, an evaporator, and a throttling element. The water system includes an electric ball valve, an outlet pipe, and an inlet pipe. The compressor outlet is connected to the condenser inlet, the condenser outlet is connected to the evaporator inlet, and the evaporator outlet is connected to the compressor inlet. A throttling element is installed in the pipe connecting the condenser and the evaporator. A temperature sensor is installed on the side of the outlet pipe and the inlet pipe near the condenser. The electric ball valve is located in the outlet pipe. The condenser outlet is connected to the outlet pipe, and the condenser inlet is connected to the inlet pipe. The temperature sensor, compressor, throttling element, electric ball valve, and controller are electrically connected. This condensation pressure control method is executed by the controller, which can be implemented in software and / or hardware. The condensation pressure control method specifically includes the following steps:

[0055] Step 210: Obtain the real-time inlet water temperature, real-time outlet water temperature, and real-time outlet liquid temperature of the condenser.

[0056] Temperature sensors are installed at the inlet, outlet, and liquid outlet of the condenser. The controller is electrically connected to each temperature sensor to obtain the real-time inlet water temperature, real-time outlet water temperature, and real-time liquid outlet temperature of the condenser.

[0057] In addition, when the refrigeration system starts to operate, the initial opening degree of the electric ball valve is determined according to the real-time inlet water temperature of the condenser. Exemplarily, when the refrigeration system starts to operate, if the real-time inlet water temperature of the condenser is greater than 18 °C, the initial opening degree of the electric ball valve is 60%; if the real-time inlet water temperature of the condenser is between 12 °C and 18 °C, the initial opening degree of the electric ball valve is 40%; if the real-time inlet water temperature of the condenser is less than 12 °C, the initial opening degree of the electric ball valve is 25%.

[0058] It should be noted that the initial opening degrees of the above-mentioned electric ball valve at different inlet water temperatures are only for illustrative purposes, and are specifically determined according to the actual performance parameters of the refrigeration system and the water circuit system, and are not limited herein.

[0059] Step 220: Take the difference between the real-time outlet water temperature and the real-time inlet water temperature as the water-side temperature difference, and take the difference between the target liquid outlet temperature and the real-time liquid outlet temperature as the refrigerant temperature difference.

[0060] Exemplarily, the target liquid outlet temperature is 30 °C.

[0061] Step 230: When the refrigerant temperature difference remains unchanged and the water-side temperature difference increases, control the opening degree of the electric ball valve to increase or remain unchanged; when the water-side temperature difference remains unchanged and the refrigerant temperature difference increases, control the opening degree of the electric ball valve to decrease.

[0062] Specifically, the variation of the opening degree of the electric ball valve with the refrigerant temperature difference T1 and the water-side temperature difference T2 is shown in Table 1. Among them, the specific adjustment opening degree of the electric ball valve corresponds to the range of the refrigerant temperature difference and the range of the water-side temperature difference (the temperature difference unit is °C). For example, when T1 ≤ -3 and T2 < 2, the opening degree of the electric ball valve is +4%, that is, the opening degree increases by 4%; when -1 < T1 ≤ 0 and T2 < 2, the opening degree of the electric ball valve is -1%, that is, the opening degree decreases by 4%. The preset time after each adjustment of the opening degree of the electric ball valve is readjusted, such as 30 s. Exemplarily, -0.5 < T1 < 0.5 is the stable state.

[0063] Table 1

[0064]

[0065] Step 240: When the refrigerant temperature difference is less than zero, control the opening degree of the electric ball valve to increase; when the refrigerant temperature difference is greater than zero, control the opening degree of the electric ball valve to decrease.

[0066] Specifically, when the refrigerant temperature difference is less than zero, the opening degree of the electric ball valve needs to increase, and the degree of increase of the opening degree of the electric ball valve is different for different ranges of the water-side temperature difference. When the refrigerant temperature difference is greater than zero, the opening degree of the electric ball valve needs to decrease, and the degree of decrease of the opening degree of the electric ball valve is different for different ranges of the water-side temperature difference.

[0067] Step 250: When the refrigerant temperature difference is less than zero and the water-side temperature difference remains unchanged, the opening degree of the electric ball valve is increased, and the required increase in the opening degree of the electric ball valve decreases as the refrigerant temperature difference increases.

[0068] Step 260: When the refrigerant temperature difference is greater than zero and the water-side temperature difference remains unchanged, the opening degree of the electric ball valve is reduced, and the required reduction in the opening degree of the electric ball valve increases with the increase of the refrigerant temperature difference.

[0069] Step 270: When the refrigerant temperature difference is less than zero and the refrigerant temperature difference remains unchanged, the opening degree of the electric ball valve is increased, and the required increase in the opening degree of the electric ball valve increases with the increase in the water-side temperature difference.

[0070] Step 280: When the refrigerant temperature difference is greater than zero and the refrigerant temperature difference remains unchanged, control the opening degree of the electric ball valve to decrease, and the required reduction in the opening degree of the electric ball valve decreases as the water-side temperature difference increases.

[0071] The changes in the opening degree of the electric ball valve with the refrigerant temperature difference and the water-side temperature difference in the above steps can be referred to Table 1. For example, the current inlet water temperature is 10℃, the current outlet water temperature is 15℃, the target condensing temperature (i.e., the target liquid outlet temperature) is 25℃, the refrigerant temperature difference is 7℃, the initial opening degree of the electric ball valve is 25%, the opening degree of the electric ball valve is reduced by 6%, that is, the opening degree is adjusted to 18%, and the next calculation begins after 30 seconds.

[0072] In addition, the opening degree of the electric ball valve can decrease or increase at a constant speed, or decrease or increase at a variable speed, depending on the actual control requirements, and is not limited here.

[0073] Step 290: When the water temperature is lower than the preset low temperature threshold, control the opening degree of the electric ball valve to the preset large opening degree.

[0074] Step 291: When the water temperature is higher than the preset high temperature threshold, control the opening degree of the electric ball valve to the preset small opening degree.

[0075] For example, the preset low temperature threshold and the preset high temperature threshold are 1.5 degrees Celsius and 15 degrees Celsius, respectively. The preset large opening can be 100% or a value less than 100%, and the preset small opening can be an opening greater than 0. The preset low temperature threshold is lower than the preset high temperature threshold, and the preset large opening is greater than the preset small opening.

[0076] In addition, a temperature sensor is installed at the compressor outlet to collect the compressor's exhaust temperature. If the exhaust temperature exceeds a certain value, such as 110°C, the electric ball valve is forcibly opened. To avoid affecting the system pressure, the adjustment rate of the electric ball valve is 3% / s; the specific value of the opening increase is not limited here. When step 290 or step 291 conflicts with the above-mentioned adjustment of the electric ball valve opening based on the exhaust temperature, the adjustment of the electric ball valve opening based on the exhaust temperature takes priority. If the water-side temperature difference is detected to be less than a certain value, such as 0.5°C, for a period of time, such as 120 seconds, the compressor unit is shut down, and the electric ball valve must be immediately adjusted to its initial opening.

[0077] It should be noted that the values ​​in Table 1 of this embodiment are only illustrative and can be determined according to the actual working requirements of the refrigeration system and water system, and are not limited here.

[0078] The condensing pressure control method for the environmental test chamber provided in this embodiment controls the opening degree of the electric ball valve in real time according to the determined water-side temperature difference and refrigerant temperature difference, thereby controlling the condensing pressure of the environmental test chamber. This solves the problems of lag and small adjustment range of pressure regulating valves in the prior art, thus ensuring control reliability.

[0079] Example 3

[0080] Figure 3 This is a structural block diagram of a condensing pressure control device for an environmental test chamber according to Embodiment 3 of the present invention. The environmental test chamber includes a chamber body, a control system, a refrigeration system, and a water system. The refrigeration system is located inside the chamber body. The control system includes a controller and a temperature sensor. The refrigeration system includes a compressor, a condenser, an evaporator, and a throttling element. The water system includes an electric ball valve, an outlet pipe, and an inlet pipe. The compressor outlet is connected to the condenser inlet, the condenser outlet is connected to the evaporator inlet, and the evaporator outlet is connected to the compressor inlet. A throttling element is installed in the pipe connecting the condenser and evaporator. A temperature sensor is installed on the side of the outlet and inlet pipes near the condenser. The electric ball valve is located in the outlet pipe. The condenser outlet is connected to the outlet pipe, and the condenser inlet is connected to the inlet pipe. The temperature sensor, compressor, throttling element, electric ball valve, and controller are electrically connected. Figure 3 The condensing pressure control device includes: a temperature acquisition module 310, a temperature difference determination module 320, and an opening control module 330. The temperature acquisition module 310 acquires the real-time inlet water temperature, real-time outlet water temperature, and real-time outlet liquid temperature of the condenser; the temperature difference determination module 320 determines the water-side temperature difference and refrigerant temperature difference of the condenser based on the real-time inlet water temperature, real-time outlet water temperature, and real-time outlet liquid temperature; and the opening control module 330 controls the opening of the electric ball valve based on the water-side temperature difference and refrigerant temperature difference to control the condensing pressure of the environmental test chamber.

[0081] Based on the above implementation, the temperature difference determination module 320 includes: a water-side temperature difference determination unit and a refrigerant temperature difference determination unit; wherein, the water-side temperature difference determination unit is used to take the difference between the real-time outlet water temperature and the real-time inlet water temperature as the water-side temperature difference; the refrigerant temperature difference determination unit is used to take the difference between the target outlet liquid temperature and the real-time outlet liquid temperature as the refrigerant temperature difference.

[0082] In one embodiment, the opening control module 330 includes a first control unit and a second control unit; wherein, the first control unit is used to control the opening of the electric ball valve to increase or remain unchanged when the refrigerant temperature difference remains unchanged and the water temperature difference increases; the second control unit is used to control the opening of the electric ball valve to decrease when the water temperature difference remains unchanged and the refrigerant temperature difference increases.

[0083] Optionally, the opening control module 330 includes a third control unit and a fourth control unit; wherein, the third control unit is used to control the opening of the electric ball valve to increase when the refrigerant temperature difference is less than zero; and the fourth control unit is used to control the opening of the electric ball valve to decrease when the refrigerant temperature difference is greater than zero.

[0084] Optionally, the opening control module 330 includes a fifth control unit, a sixth control unit, a seventh control unit, and an eighth control unit; wherein, the fifth control unit is used to control the opening of the electric ball valve to increase when the refrigerant temperature difference is less than zero and the water-side temperature difference remains constant, and the required increase in opening of the electric ball valve decreases as the refrigerant temperature difference increases; the sixth control unit is used to control the opening of the electric ball valve to decrease when the refrigerant temperature difference is greater than zero and the water-side temperature difference remains constant, and the required decrease in opening of the electric ball valve increases as the refrigerant temperature difference increases; the seventh control unit is used to control the opening of the electric ball valve to increase when the refrigerant temperature difference is less than zero and the refrigerant temperature difference remains constant, and the required increase in opening of the electric ball valve increases as the water-side temperature difference increases; the eighth control unit is used to control the opening of the electric ball valve to decrease when the refrigerant temperature difference is greater than zero and the refrigerant temperature difference remains constant, and the required decrease in opening of the electric ball valve decreases as the water-side temperature difference increases.

[0085] Optionally, the opening control module 330 includes a ninth control unit and a tenth control unit; wherein, the ninth control unit is used to control the opening of the electric ball valve to a preset large opening when the water side temperature is lower than a preset low temperature threshold; the tenth control unit is used to control the opening of the electric ball valve to a preset small opening when the water side temperature is higher than a preset high temperature threshold.

[0086] Optionally, the above-mentioned condensing pressure control device further includes an initial opening determination module, which is used to determine the initial opening of the electric ball valve based on the real-time inlet water temperature, real-time outlet water temperature and real-time liquid outlet temperature after the temperature acquisition module acquires the real-time inlet water temperature, real-time outlet water temperature and real-time liquid outlet temperature of the condenser.

[0087] The condensation pressure control device for the environmental test chamber provided in this embodiment belongs to the same inventive concept as the condensation pressure control method for the environmental test chamber provided in any embodiment of the present invention, and has corresponding beneficial effects. For technical details not detailed in this embodiment, please refer to the condensation pressure control method for the environmental test chamber provided in any embodiment of the present invention.

[0088] Example 4

[0089] Figure 4 This is a schematic diagram of a partial structure of an environmental test chamber provided in Embodiment 4 of the present invention. (Reference) Figure 4 The environmental test chamber includes: a chamber body (not shown in the figure), a control system, a refrigeration system, and a water system. The refrigeration system is located inside the chamber body. The control system includes a controller (not shown in the figure) and temperature sensors T1, T2, and T3. The refrigeration system includes a compressor 10, a condenser 20, an evaporator 30, and a throttling element 40. The water system includes an electric ball valve 50, an outlet pipe 60, and an inlet pipe 70. The outlet of the compressor 10 is connected to the liquid inlet of the condenser 20, the outlet of the condenser 20 is connected to the inlet of the evaporator 30, and the outlet of the evaporator 30 is connected to the inlet of the compressor 10. The pipe connecting the condenser 20 and the evaporator 30 is equipped with... A throttling element 40 is provided. Temperature sensors T1 and T2 are respectively installed on the side of the water outlet pipe 60 and the water inlet pipe 70 near the condenser 20. An electric ball valve 50 is located in the water outlet pipe 60. The water outlet of the condenser 20 is connected to the water outlet pipe 60, and the water inlet of the condenser 20 is connected to the water inlet pipe 70. A temperature sensor T3 is installed on the side of the pipe connected to the liquid outlet of the condenser 20 near the liquid outlet of the condenser 20. Temperature sensors T1, T2, T3, compressor 10, throttling element 40, and electric ball valve 50 are electrically connected to the controller. The condensing pressure control device of the environmental test chamber provided in any embodiment of the present invention is integrated into the controller. The side of the water outlet pipe 60 and the water inlet pipe 70 away from the condenser 20 is connected to the cooling tower, and a temperature sensor is installed at the outlet of the compressor 10. The controller is used to control the working status of the compressor and, based on the temperature collected by each temperature sensor, controls the opening degree of the electric ball valve. The specific control process of the controller on the opening degree of the electric ball valve can be referred to any of the above embodiments, and will not be repeated here.

[0090] Furthermore, the refrigeration system comprises two subsystems, each including a compressor, condenser, evaporator, and throttling element. One subsystem has a low-temperature compressor, and the other has a high-temperature compressor. The two subsystems are connected via a plate heat exchanger 100. Figure 4 The compressor 10 is a high-temperature side compressor.

[0091] Optionally, a water pressure gauge 80 is installed in both the inlet and outlet water pipes, and a water pressure protector 90 is also installed in the inlet water pipe. The water pressure gauge 80 measures and displays the water pressure in the pipe, and the water pressure protector 90 provides water pressure protection for the pipe.

[0092] The refrigeration system provided in this embodiment belongs to the same inventive concept as the condensing pressure control method of the environmental test chamber provided in any embodiment of the present invention, and has corresponding beneficial effects. For technical details not covered in this embodiment, please refer to the condensing pressure control method of the environmental test chamber provided in any embodiment of the present invention.

[0093] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, combinations, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A method for controlling the condensation pressure of an environmental test chamber, characterized in that, The environmental test chamber includes a chamber body, a control system, a refrigeration system, and a water system. The refrigeration system is located inside the chamber body. The control system includes a controller and a temperature sensor. The refrigeration system includes a compressor, a condenser, an evaporator, and a throttling element. The water system includes an electric ball valve, an outlet pipe, and an inlet pipe. The compressor outlet is connected to the condenser inlet, the condenser outlet is connected to the evaporator inlet, and the evaporator outlet is connected to the compressor inlet. The throttling element is installed in the pipe connecting the condenser and the evaporator. The temperature sensor is installed on the side of the outlet pipe and the inlet pipe near the condenser. The electric ball valve is located in the outlet pipe. The condenser outlet is connected to the outlet pipe, and the condenser inlet is connected to the inlet pipe. The temperature sensor, the compressor, the throttling element, the electric ball valve, and the controller are electrically connected. The condensing pressure control method is executed by the controller, and the condensing pressure control method includes: The real-time inlet water temperature, real-time outlet water temperature, and real-time outlet liquid temperature of the condenser are obtained. The water-side temperature difference and refrigerant temperature difference of the condenser are determined based on the real-time inlet water temperature, the real-time outlet water temperature, and the real-time outlet liquid temperature. The opening degree of the electric ball valve is controlled based on the water-side temperature difference and the refrigerant temperature difference to control the condensation pressure of the environmental test chamber; the water-side temperature difference is the difference between the real-time outlet water temperature and the real-time inlet water temperature, and the refrigerant temperature difference is the difference between the target outlet liquid temperature and the real-time outlet liquid temperature.

2. The condensing pressure control method according to claim 1, characterized in that, The step of determining the water-side temperature difference and refrigerant temperature difference of the condenser based on the real-time inlet water temperature, the real-time outlet water temperature, and the real-time outlet liquid temperature includes: The difference between the real-time outlet water temperature and the real-time inlet water temperature is taken as the water-side temperature difference; The difference between the target outlet temperature and the real-time outlet temperature is taken as the refrigerant temperature difference.

3. The condensing pressure control method according to claim 1, characterized in that, The step of controlling the opening degree of the electric ball valve based on the water-side temperature difference and the refrigerant temperature difference includes: When the refrigerant temperature difference remains constant and the water-side temperature difference increases, the opening degree of the electric ball valve is controlled to increase or remain constant. When the water-side temperature difference remains constant and the refrigerant temperature difference increases, the opening degree of the electric ball valve is reduced.

4. The condensing pressure control method according to claim 1, characterized in that, The step of controlling the opening degree of the electric ball valve based on the water-side temperature difference and the refrigerant temperature difference includes: When the refrigerant temperature difference is less than zero, the opening degree of the electric ball valve is increased. When the refrigerant temperature difference is greater than zero, the opening degree of the electric ball valve is reduced.

5. The condensing pressure control method according to claim 1, characterized in that, The step of controlling the opening degree of the electric ball valve based on the water-side temperature difference and the refrigerant temperature difference includes: When the refrigerant temperature difference is less than zero and the water-side temperature difference remains unchanged, the opening degree of the electric ball valve is increased, and the required increase in the opening degree of the electric ball valve decreases as the refrigerant temperature difference increases. When the refrigerant temperature difference is greater than zero and the water-side temperature difference remains unchanged, the opening degree of the electric ball valve is reduced, and the required reduction in the opening degree of the electric ball valve increases with the increase of the refrigerant temperature difference. When the refrigerant temperature difference is less than zero and the refrigerant temperature difference remains unchanged, the opening degree of the electric ball valve is increased, and the required increase in the opening degree of the electric ball valve increases with the increase in the water-side temperature difference. When the refrigerant temperature difference is greater than zero and the refrigerant temperature difference remains constant, the opening degree of the electric ball valve is reduced, and the required reduction in the opening degree of the electric ball valve decreases as the water-side temperature difference increases.

6. The condensing pressure control method according to claim 1, characterized in that, The step of controlling the opening degree of the electric ball valve based on the water-side temperature difference and the refrigerant temperature difference includes: When the water-side temperature difference is lower than a preset low temperature threshold, the opening degree of the electric ball valve is controlled to a preset large opening degree; When the water-side temperature difference is higher than a preset high-temperature threshold, the opening degree of the electric ball valve is controlled to a preset small opening degree.

7. The condensing pressure control method according to claim 1, characterized in that, After obtaining the real-time inlet water temperature, real-time outlet water temperature, and real-time outlet liquid temperature of the condenser, the method further includes: The initial opening degree of the electric ball valve is determined based on the real-time inlet water temperature.

8. A condensation pressure control device for an environmental test chamber, characterized in that, The environmental test chamber includes a chamber body, a control system, a refrigeration system, and a water system. The refrigeration system is located inside the chamber body. The control system includes a controller and a temperature sensor. The refrigeration system includes a compressor, a condenser, an evaporator, and a throttling element. The water system includes an electric ball valve, an outlet pipe, and an inlet pipe. The compressor outlet is connected to the condenser inlet, the condenser outlet is connected to the evaporator inlet, and the evaporator outlet is connected to the compressor inlet. The throttling element is installed in the pipe connecting the condenser and the evaporator. The temperature sensor is installed on the side of the outlet pipe and the inlet pipe near the condenser. The electric ball valve is located in the outlet pipe. The condenser outlet is connected to the outlet pipe, and the condenser inlet is connected to the inlet pipe. The temperature sensor, the compressor, the throttling element, the electric ball valve, and the controller are electrically connected. The condensation pressure control device includes: The temperature acquisition module is used to acquire the real-time inlet water temperature, real-time outlet water temperature and real-time outlet liquid temperature of the condenser. The temperature difference determination module is used to determine the water-side temperature difference and refrigerant temperature difference of the condenser based on the real-time inlet water temperature, the real-time outlet water temperature, and the real-time outlet liquid temperature. The opening control module is used to control the opening degree of the electric ball valve according to the water-side temperature difference and the refrigerant temperature difference, so as to control the condensing pressure of the environmental test chamber; the water-side temperature difference is the difference between the real-time outlet water temperature and the real-time inlet water temperature, and the refrigerant temperature difference is the difference between the target outlet liquid temperature and the real-time outlet liquid temperature.

9. An environmental test chamber, characterized in that, include: The system comprises a housing, a control system, a refrigeration system, and a water system. The refrigeration system is located inside the housing. The control system includes a controller and a temperature sensor. The refrigeration system includes a compressor, a condenser, an evaporator, and a throttling element. The water system includes an electric ball valve, an outlet pipe, and an inlet pipe. The compressor outlet is connected to the condenser inlet, the condenser outlet is connected to the evaporator inlet, and the evaporator outlet is connected to the compressor inlet. The throttling element is installed in the pipe connecting the condenser and the evaporator. The temperature sensor is installed on the side of the outlet pipe and the inlet pipe near the condenser. The electric ball valve is located in the outlet pipe. The condenser outlet is connected to the outlet pipe, and the condenser inlet is connected to the inlet pipe. The temperature sensor, the compressor, the throttling element, the electric ball valve, and the controller are electrically connected. The condensing pressure control device as described in claim 8 is integrated into the controller.

10. The environmental test chamber according to claim 9, characterized in that, Both the inlet and outlet water pipes are equipped with water pressure gauges, and the inlet water pipe is also equipped with a water pressure protector.

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