A control method and control system for a redundant dual mode refrigeration apparatus

Abstract

The application relates to the technical field of liquid cooling heat dissipation, and provides a control method and a control system of a redundant dual-mode refrigeration device. In the application, when the cooling liquid temperature is greater than a first temperature threshold, the second refrigeration circuit is started, and the three-way valve is adjusted to guide the inlet and the second outlet, when the cooling liquid temperature is not greater than the first temperature threshold, the on-circuit of the three-way valve is adjusted according to the outer water temperature, and the first refrigeration circuit or the second refrigeration circuit is selectively passed through to dissipate heat. The way of starting the first refrigeration circuit or the second refrigeration circuit to refrigerate according to the cooling liquid temperature and the outer water temperature enables the cooling liquid to be cooled by the first refrigeration circuit or the second refrigeration circuit in different temperature ranges, effectively cools the cooling liquid, enhances the stability of the system, and enables the redundant dual-mode refrigeration device to work stably for a long time.

Description

Technical Field

[0001] This invention relates to the field of liquid cooling technology, and in particular to a control method and control system for a redundant dual-mode refrigeration device. Background Technology

[0002] Currently, units using specific chips generally have high heat flux density and high overall heat dissipation. Equipment such as cabinets using these units typically employ liquid cooling for overall heat dissipation. This liquid cooling method requires a continuous, circulating supply of external coolant that meets specific temperature, flow rate, and pressure requirements to remove heat from the cabinet equipment. However, existing cooling equipment struggles to operate stably for extended periods in complex and harsh environments, resulting in poor cooling performance and the cooled equipment failing to meet operating temperature requirements.

[0003] Therefore, overcoming the shortcomings of the existing technology is an urgent problem to be solved in this technical field. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a control method and control system for a redundant dual-mode refrigeration device, which solves the problem that existing refrigeration devices cannot work stably for a long time in complex and harsh environments and have poor refrigeration effect.

[0005] In a first aspect, the present invention provides a control method for a redundant dual-mode refrigeration device, the redundant dual-mode refrigeration device comprising a first refrigeration circuit, a second refrigeration circuit, a cooling circuit, and a three-way valve, wherein the inlet of the three-way valve is connected to the cooling circuit, the first outlet of the three-way valve is connected to the first refrigeration circuit, and the second outlet of the three-way valve is connected to the second refrigeration circuit; the control method includes:

[0006] Detect the coolant temperature in the cooling circuit;

[0007] If the coolant temperature is greater than the first temperature threshold, the second refrigeration circuit is activated, and the three-way valve is adjusted to connect the inlet and the second outlet, so that the heat of the coolant is absorbed through the second refrigeration circuit.

[0008] If the coolant temperature is not greater than the first temperature threshold, the external water temperature of the first refrigeration circuit is detected, and the conduction circuit of the three-way valve is adjusted according to the external water temperature to selectively dissipate heat through the first refrigeration circuit or the second refrigeration circuit.

[0009] Further, the step of activating the second refrigeration circuit if the coolant temperature is greater than the first temperature threshold, and adjusting the three-way valve to connect the inlet and the second outlet, thereby absorbing heat from the coolant through the second refrigeration circuit, includes:

[0010] If the coolant temperature is greater than the first temperature threshold, then the second refrigeration circuit is activated;

[0011] Within a preset time period, the flow rate of coolant flowing through the first refrigeration circuit is gradually reduced by the three-way valve, and the flow rate of coolant flowing through the second refrigeration circuit is gradually increased.

[0012] After the entire flow of the coolant has passed through the second refrigeration circuit, the first refrigeration circuit is shut off.

[0013] Further, the step of activating the second refrigeration circuit if the coolant temperature is greater than the first temperature threshold, and adjusting the three-way valve to connect the inlet and the second outlet, thereby absorbing heat from the coolant through the second refrigeration circuit, includes:

[0014] If the coolant temperature is greater than the first temperature threshold, then the second refrigeration circuit is activated;

[0015] The flow rate through the second refrigeration circuit is adjusted according to the temperature of the coolant.

[0016] Further, the step of detecting the external water temperature of the first refrigeration circuit if the coolant temperature is not greater than a first temperature threshold, and adjusting the conduction circuit of the three-way valve according to the external water temperature to selectively dissipate heat through the first refrigeration circuit or the second refrigeration circuit includes:

[0017] If the coolant temperature is not greater than the first temperature threshold, then the external water temperature of the first refrigeration circuit is detected;

[0018] If the outside water temperature is not greater than the second temperature threshold, start the first refrigeration circuit and adjust the three-way valve to connect the inlet and the first outlet, so as to absorb the heat of the coolant through the first refrigeration circuit.

[0019] If the external water temperature is greater than the second temperature threshold, the second refrigeration circuit is activated, and the three-way valve is adjusted to connect the inlet and the second outlet, so that the coolant flows to the second refrigeration circuit for heat dissipation.

[0020] Furthermore, the first refrigeration circuit is a plate heat exchange circuit, the second refrigeration circuit is an evaporator circuit, the plate heat exchange circuit includes a plate heat exchanger, the evaporator circuit includes an evaporator and a compressor, the cooling circuit includes a circulating pump and a heater, and the coolant in the cooling circuit can exchange heat with the refrigerant in the evaporator circuit or the external water in the plate heat exchange circuit.

[0021] Furthermore, the circulating pump includes a main circulating pump and a standby circulating pump, and the compressor includes a main compressor and a standby compressor. When the second refrigeration circuit is operating, the control method further includes:

[0022] The backup circulation pump may be used selectively depending on the status of the main circulation pump, the flow rate of the coolant, and / or the pressure of the coolant.

[0023] The standby compressor may be selectively used based on the operating status of the main compressor and / or the coolant temperature of the cooling circuit.

[0024] Further, the selective use of a backup circulation pump based on the status of the main circulation pump, the flow rate of the coolant, and / or the pressure of the coolant includes:

[0025] When the coolant flow rate is detected to be lower than the set flow rate threshold and an alarm signal is received, the backup circulation pump is turned on and the main circulation pump is turned off.

[0026] When the coolant pressure is detected to be lower than the set pressure threshold and an alarm signal is received, the backup circulation pump is turned on and the main circulation pump is turned off.

[0027] When overcurrent is detected in the main circulation pump, the backup circulation pump is turned on and the main circulation pump is turned off.

[0028] After the main circulation pump has been operating for a preset time, the backup circulation pump is turned on and the main circulation pump is turned off.

[0029] When the refrigeration equipment is turned on, the pump with the shortest cumulative running time is selected for operation first, and the currently running pump is used as the main circulation pump.

[0030] Furthermore, the compressor employs a configuration of one main compressor and one standby compressor. The standby compressor is selectively used based on the operating status of the main compressor and / or the coolant temperature of the cooling circuit, including:

[0031] When the coolant temperature is detected to be higher than the set temperature threshold and an alarm signal is received, the backup compressor is turned on and the main compressor is turned off.

[0032] When a failure is detected in the main compressor, the backup compressor is activated and the main compressor is shut down.

[0033] When the pressure value of the evaporator circuit is detected to exceed the preset pressure range, the backup compressor is turned on and the main compressor is turned off.

[0034] After the main compressor has been operating for a preset time, the standby compressor is turned on and the main compressor is turned off.

[0035] When the refrigeration equipment is turned on, the compressor with the shortest cumulative running time is selected first, and the currently running compressor is used as the main compressor.

[0036] Furthermore, the control method further includes:

[0037] Detect the coolant temperature; when the coolant temperature is lower than the set temperature, check whether the circulation pump and compressor are running.

[0038] If the circulating pump is running and the compressor is not running, turn on the heater until the coolant temperature is not lower than the set temperature.

[0039] Secondly, the present invention provides a control system for a redundant dual-mode refrigeration device. The control system for the redundant dual-mode refrigeration device includes a PLC controller, a first sensor, a first solenoid valve, and a second solenoid valve, and is used to execute the control method for the redundant dual-mode refrigeration device described in the first aspect. The controlled redundant dual-mode refrigeration device includes: a first refrigeration circuit, a second refrigeration circuit, a cooling circuit, and a three-way valve. The inlet of the three-way valve is connected to the cooling circuit, the first outlet of the three-way valve is connected to the first refrigeration circuit, and the second outlet of the three-way valve is connected to the second refrigeration circuit. The three-way valve is used to allow refrigerant to flow to the first refrigeration circuit or the second refrigeration circuit.

[0040] The first temperature sensor is installed in the cooling circuit to monitor the temperature of the coolant in the cooling circuit;

[0041] The first solenoid valve is installed in the first refrigeration circuit and is used to close or start the first refrigeration circuit.

[0042] The second solenoid valve is installed in the second refrigeration circuit and is used to shut down or start the second refrigeration circuit;

[0043] The PLC control module is connected to the first temperature sensor, the first solenoid valve, the second solenoid valve and the three-way valve respectively. The PLC control module is used to receive the coolant temperature monitored by the first temperature sensor and adjust the three-way valve according to the coolant temperature.

[0044] If the coolant temperature is greater than the first temperature threshold, the PLC control module controls the second solenoid valve to start the second refrigeration circuit and adjusts the three-way valve to connect the inlet and the second outlet so as to absorb the heat of the coolant through the second refrigeration circuit.

[0045] If the coolant temperature is not greater than the first temperature threshold, the PLC control module is used to detect the external water temperature of the first refrigeration circuit and adjust the conduction circuit of the three-way valve according to the external water temperature to selectively dissipate heat through the first refrigeration circuit or the second refrigeration circuit.

[0046] Furthermore, the control system also includes a second temperature sensor; the second temperature sensor is arranged in the first refrigeration circuit for monitoring the temperature of the external water;

[0047] The PLC control module is also connected to the second temperature sensor to obtain the temperature of the external water and adjust the three-way valve according to the temperature of the external water.

[0048] When the coolant temperature is not greater than the first temperature threshold and the outside water temperature is not greater than the second temperature threshold, the PLC control module is used to start the first refrigeration circuit and adjust the three-way valve to connect the inlet and the first outlet, so as to absorb the heat of the coolant through the first refrigeration circuit.

[0049] When the coolant temperature is not greater than the first temperature threshold and the outside water temperature is greater than the second temperature threshold, the PLC control module is used to start the second refrigeration circuit and adjust the three-way valve to connect the inlet and the second outlet, so that the coolant flows to the second refrigeration circuit and dissipates heat through the second refrigeration circuit.

[0050] Furthermore, the control system also includes a pressure sensor and a flow sensor;

[0051] The pressure sensor is installed in the second refrigeration circuit to monitor the pressure within the second refrigeration circuit;

[0052] The flow sensor is installed in the cooling circuit to monitor the flow rate of the coolant in the cooling circuit.

[0053] In this invention, the first or second refrigeration circuit is activated based on the coolant temperature and the external water temperature. When the coolant temperature exceeds a first temperature threshold, the second refrigeration circuit is activated, and the three-way valve is adjusted to connect the inlet to the second outlet. When the coolant temperature is below the first temperature threshold, the three-way valve is adjusted according to the external water temperature to selectively dissipate heat through either the first or second refrigeration circuit. This method of activating the first or second refrigeration circuit based on the coolant and external water temperatures allows the coolant to be cooled using either the first or second refrigeration circuit at different temperature ranges. This ensures effective cooling of the coolant while enhancing system stability, enabling the redundant dual-mode refrigeration equipment to operate stably for extended periods. Attached Figure Description

[0054] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments of the present invention will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0055] Figure 1 This is a flowchart illustrating a control method for a redundant dual-mode refrigeration device provided in an embodiment of the present invention.

[0056] Figure 2a This is a schematic diagram of the specific process of step 102 in the control method of a redundant dual-mode refrigeration device provided in an embodiment of the present invention;

[0057] Figure 2b This is a schematic diagram of the specific process of step 103 in the control method of a redundant dual-mode refrigeration device provided in an embodiment of the present invention;

[0058] Figure 3a This is a schematic diagram of the structure of a redundant dual-mode refrigeration device provided in an embodiment of the present invention;

[0059] Figure 3b This is another structural schematic diagram of a redundant dual-mode refrigeration device provided in an embodiment of the present invention;

[0060] Figure 4 This is a schematic diagram of the specific process for switching the circulating pump in the control method of a redundant dual-mode refrigeration device provided in an embodiment of the present invention;

[0061] Figure 5 This is a logic diagram of the switching of the circulating pump in a control method for a redundant dual-mode refrigeration device provided in an embodiment of the present invention;

[0062] Figure 6 This is a schematic diagram illustrating the specific process of switching compressors in a control method for a redundant dual-mode refrigeration device provided in an embodiment of the present invention;

[0063] Figure 7 This is a schematic diagram of the start-up logic of the electric heater in a control method for a redundant dual-mode refrigeration device provided in an embodiment of the present invention;

[0064] Figure 8 This is a logical diagram of the sensor monitoring process in a control method for a redundant dual-mode refrigeration device provided in an embodiment of the present invention;

[0065] Figure 9This is a schematic diagram of the switching control logic of two heat dissipation modes in the control system of a redundant dual-mode refrigeration device provided in an embodiment of the present invention;

[0066] Figure 10 This is a schematic diagram of the control system of a redundant dual-mode refrigeration device provided in an embodiment of the present invention;

[0067] Figure 11 This is a schematic diagram of the operation mode of a control system for a redundant dual-mode refrigeration device provided in an embodiment of the present invention;

[0068] Figure 12 This is a communication logic diagram of the control system of a redundant dual-mode refrigeration device provided in an embodiment of the present invention. Detailed Implementation

[0069] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0070] In the description of this invention, the terms "inner", "outer", "longitudinal", "lateral", "upper", "lower", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and do not require that this invention must be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0071] Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0072] Example 1:

[0073] Embodiment 1 of the present invention provides a control method for a redundant dual-mode refrigeration device. The redundant dual-mode refrigeration device includes a first refrigeration circuit, a second refrigeration circuit, a cooling circuit, and a three-way valve. The inlet of the three-way valve is connected to the cooling circuit, the first outlet of the three-way valve is connected to the first refrigeration circuit, and the second outlet of the three-way valve is connected to the second refrigeration circuit. Figure 1 The control method includes:

[0074] Step 101: Detect the coolant temperature of the cooling circuit.

[0075] Step 102: If the coolant temperature is greater than the first temperature threshold, the second refrigeration circuit is started, and the three-way valve is adjusted to connect the inlet and the second outlet, so that the heat of the coolant is absorbed through the second refrigeration circuit.

[0076] Step 103: If the coolant temperature is not greater than the first temperature threshold, the external water temperature of the first refrigeration circuit is detected, and the conduction circuit of the three-way valve is adjusted according to the external water temperature to selectively dissipate heat through the first refrigeration circuit or the second refrigeration circuit.

[0077] In this embodiment, the coolant temperature and the external water temperature are obtained by a temperature sensor. The temperature of the coolant is the temperature after passing through the device being cooled and before entering the first refrigeration circuit and the second refrigeration circuit. The cooling capacity of the second refrigeration circuit is better than that of the first refrigeration circuit, and the second temperature threshold is lower than the first temperature threshold.

[0078] In practical applications, the first temperature threshold can be 28°C, the second temperature threshold can be 20°C, and the cooling circuit is equipped with a device to be cooled. The coolant is used to cool the device. When the coolant absorbs heat from the device and causes its temperature to rise, when the coolant temperature is greater than 28°C, the three-way valve connects the second refrigeration circuit and the cooling circuit. The coolant is cooled in the second refrigeration circuit and then cools the device. When the coolant temperature is not greater than 28°C, the first or second refrigeration circuit is selected to cool the coolant according to the external water temperature.

[0079] In other alternative solutions, the specific values ​​of the first temperature threshold and the second temperature threshold can also be other values, depending on the operating environment of the refrigeration equipment and the type of coolant.

[0080] In this embodiment of the invention, the first or second refrigeration circuit is activated for cooling based on the coolant temperature and the external water temperature. This allows the coolant to be cooled using either the first or second refrigeration circuit at different temperature ranges, ensuring effective cooling of the coolant while enhancing the stability of the system. This enables the redundant dual-mode refrigeration equipment to operate stably for extended periods.

[0081] In an optional embodiment, step 102 includes:

[0082] If the coolant temperature is greater than the first temperature threshold, the second refrigeration circuit is activated, and the flow rate through the second refrigeration circuit is adjusted according to the coolant temperature.

[0083] The third temperature threshold must be greater than the first temperature threshold, and the cooling effect of the second refrigeration circuit must be stronger than that of the first refrigeration circuit. When the coolant temperature exceeds the first temperature threshold, the second refrigeration circuit is activated, and the flow rate of coolant entering the first and second refrigeration circuits is controlled by the three-way valve. For example, when the coolant temperature rises further, the flow rate of coolant entering the second refrigeration circuit is increased by the three-way valve, and when the coolant temperature drops, the flow rate of coolant entering the second refrigeration circuit is reduced by the three-way valve.

[0084] Combination Figure 2a Step 102 specifically includes:

[0085] Step 1021: If the coolant temperature is greater than the first temperature threshold, then start the second refrigeration circuit.

[0086] If the coolant temperature is greater than the first temperature threshold, the first refrigeration circuit is considered to be unable to meet the heat dissipation requirements of the coolant, and the second refrigeration circuit needs to be activated.

[0087] Step 1022: Within a preset time period, gradually reduce the flow rate of coolant flowing through the first refrigeration circuit through the three-way valve, and gradually increase the flow rate of coolant flowing through the second refrigeration circuit.

[0088] In the process of switching the heat dissipation circuit to the second refrigeration circuit, instead of immediately cutting off the inlet and first outlet of the three-way valve and immediately fully opening the inlet and second outlet of the three-way valve, the inlet and first outlet of the three-way valve are gradually closed, and the inlet and second outlet of the three-way valve are gradually opened. This is manifested as the coolant flow rate through the first refrigeration circuit gradually decreasing and the coolant flow rate through the second refrigeration circuit increasing.

[0089] The second refrigeration circuit has a certain start-up time. However, during the initial period before the second refrigeration circuit starts up, i.e., the preset time in step 1022, the cooling capacity of the second refrigeration circuit cannot reach its peak value. If all the coolant flows to the second refrigeration circuit at this time, the cooling effect of the refrigeration equipment will be reduced for a certain period of time, and the stability of the refrigeration equipment during operation will be reduced. By gradually increasing the coolant flow rate of the second refrigeration circuit and gradually decreasing the coolant flow rate of the first refrigeration circuit, the negative impact on the cooling capacity of the refrigeration equipment during the initial period after the second refrigeration circuit starts up can be reduced.

[0090] When the coolant flow to the first circuit is immediately cut off and the inlet and second outlet of the three-way valve are immediately and completely opened, combined with Figure 3aA portion of coolant will remain in the pipe from the first outlet of the three-way valve to the intersection shown in the diagram. This reduces the total amount of coolant circulating in the cooling circuit, thus affecting the cooling effect of the refrigeration equipment and reducing its operational stability. Furthermore, when switching from the second refrigeration circuit to the first refrigeration circuit, the coolant remaining in this pipe will not be cooled during the second circuit's operation, leading to uncontrollable temperature control and potentially failing to effectively cool the components, further reducing the stability of the refrigeration equipment. By gradually increasing the coolant flow rate in the second refrigeration circuit and gradually decreasing the coolant flow rate in the first refrigeration circuit, the amount of coolant residue in the pipe from the first outlet to the intersection shown in the diagram can be reduced, further increasing the stability of the refrigeration equipment during operation.

[0091] Step 1023: After the coolant has flowed through the second refrigeration circuit, shut down the first refrigeration circuit.

[0092] When the cooling capacity of the second refrigeration circuit reaches its peak and all the coolant flows to the second refrigeration circuit, there is no coolant flowing in the first refrigeration circuit, so the first refrigeration circuit needs to be shut down.

[0093] Combination Figure 2b In an optional embodiment, step 103 specifically includes:

[0094] Step 1031: If the coolant temperature is not greater than the first temperature threshold, then detect the external water temperature of the first refrigeration circuit.

[0095] Step 1032: If the outside water temperature is not greater than the second temperature threshold, start the first refrigeration circuit and adjust the three-way valve to connect the inlet and the first outlet, so as to absorb the heat of the coolant through the first refrigeration circuit.

[0096] Step 1033: If the external water temperature is greater than the second temperature threshold, start the second refrigeration circuit and adjust the three-way valve to connect the inlet and the second outlet, so that the coolant flows to the second refrigeration circuit and dissipates heat through the second refrigeration circuit.

[0097] In practical applications, when the coolant temperature is greater than 28°C, a second refrigeration circuit is used to cool the coolant; when the coolant temperature is not greater than 28°C and the external water temperature is not greater than 20°C, the first refrigeration circuit is used to cool the coolant; when the coolant temperature is not greater than 28°C and the external water temperature is greater than 20°C, a second refrigeration circuit is used to cool the coolant.

[0098] In this embodiment, combined with Figure 3aThe first refrigeration circuit is a plate heat exchange circuit, the second refrigeration circuit is an evaporator circuit, the plate heat exchange circuit includes a plate heat exchanger, the evaporator circuit includes an evaporator and a compressor, the cooling circuit includes a circulating pump and a heater, and the coolant in the cooling circuit can exchange heat with the refrigerant in the evaporator circuit or the external water in the plate heat exchange circuit.

[0099] Plate heat exchanger circuits use external water to cool the coolant. The external water only needs to be pumped into the plate heat exchanger to exchange heat. The external water can be discharged directly from the equipment after heat exchange. This makes the plate heat exchanger circuit simple in structure and has a low failure rate, but the heat dissipation effect is generally average. On the other hand, evaporator circuits use refrigerant to cool the coolant. Evaporator circuits contain components such as compressors, which are prone to failure during long-term operation, but the heat dissipation effect is good.

[0100] When using a plate heat exchanger circuit to cool the coolant, the flow rate of the coolant entering the plate heat exchanger circuit is controlled by adjusting the three-way valve, thereby controlling the coolant temperature between a first temperature threshold and a second temperature threshold, for example, controlling the coolant temperature between 28°C and 20°C. When the coolant temperature is low, the flow rate of the coolant entering the plate heat exchanger circuit can be reduced, while when the coolant temperature is high, the flow rate of the coolant entering the plate heat exchanger circuit can be increased. When the flow rate of the coolant entering the plate heat exchanger reaches its peak, but the coolant temperature is still higher than 28°C, the plate heat exchanger circuit can no longer meet the cooling requirements of the coolant, and an evaporator circuit needs to be used to dissipate heat from the coolant. At this time, the evaporator circuit is started, and the three-way valve is adjusted so that all the coolant flows through the evaporator circuit.

[0101] The ingenuity of this control method lies in the fact that, under normal circumstances, a plate heat exchanger circuit is used to cool the coolant. Only when the plate heat exchanger circuit using external water to cool the coolant cannot meet the heat dissipation requirements will the evaporator circuit be used to cool the coolant. The evaporator circuit will only be used to cool the coolant if the coolant temperature or the external water temperature is too high. This reduces the usage time of the evaporator circuit, reduces the probability of evaporator circuit failure, and ensures the cooling efficiency of the entire refrigeration equipment.

[0102] To prevent refrigeration equipment from easily malfunctioning during use, such as Figure 3b As shown, the circulation pump includes a main circulation pump and a standby circulation pump, and the compressor includes a main compressor and a standby compressor. When the second refrigeration circuit is working, the control method further includes: selectively using the standby circulation pump according to the status of the main circulation pump, the flow rate of the coolant and / or the pressure of the coolant; and selectively using the standby compressor according to the operating status of the main compressor and / or the coolant temperature of the cooling circuit.

[0103] In this embodiment, to prevent the refrigeration equipment from failing due to a malfunction of the circulating pump, a backup circulating pump needs to be selectively used based on the status of the main circulating pump, the flow rate of the coolant, and / or the pressure of the coolant. Figure 4 As shown, the control method further includes:

[0104] Step 201: When the coolant flow rate is detected to be lower than the set flow rate threshold and an alarm signal is received, the backup circulation pump is turned on and the main circulation pump is turned off.

[0105] Step 202: When the coolant pressure is detected to be lower than the set pressure threshold and an alarm signal is received, the backup circulation pump is turned on and the main circulation pump is turned off.

[0106] Step 203: When the main circulation pump is detected to be overflowing, the backup circulation pump is turned on and the main circulation pump is turned off.

[0107] Step 204: After the main circulation pump has been operating for a preset time, turn on the backup circulation pump and turn off the main circulation pump.

[0108] Step 205: When the refrigeration equipment is started, the pump with the shortest cumulative running time is selected first, and the currently running pump is used as the main circulation pump.

[0109] Steps 203-205 are used to control the switching between the main circulating pump and the standby circulating pump. This ensures that if one circulating pump fails, the other can start as quickly as possible, and the failed circulating pump can be shut down and repaired promptly. This guarantees the normal operation of the refrigeration equipment even in the event of a circulating pump failure. Steps 204 and 205 balance the overall operating time of the two circulating pumps, preventing failures due to excessive operating time. The advantage of this control method is that it reduces the probability of circulating pump failures, ensuring the refrigeration equipment continues to operate normally even if one pump fails, thus improving the stability of the refrigeration system.

[0110] Combination Figure 5 After the main circulation pump has been running continuously for 168 hours, the automatic switching logic of the main circulation pump is activated, and the main circulation pump stops running. If the standby circulation pump fails to start, a low coolant pressure or flow alarm is triggered after a three-second delay, and a maintenance message is issued, and the main circulation pump is put back into operation.

[0111] To prevent refrigeration equipment failure due to compressor malfunction, a configuration of one main compressor and one standby compressor is used. The main compressor and standby compressor need to be switched according to the operating status of the compressor and evaporator circuits. Figure 6 The control method further includes:

[0112] Step 301: When the coolant temperature is detected to be higher than the set temperature threshold and an alarm signal is received, the backup compressor is turned on and the main compressor is turned off.

[0113] Step 302: When a failure is detected in the main compressor, start the backup compressor and shut down the main compressor.

[0114] Step 303: When the pressure value of the evaporator circuit is detected to exceed the preset pressure range, start the backup compressor and shut down the main compressor.

[0115] Step 304: After the main compressor has been working for a preset time, start the standby compressor and turn off the main compressor.

[0116] Step 305: When the refrigeration equipment is turned on, the compressor with the shortest cumulative running time is selected first and the currently running compressor is selected as the main compressor.

[0117] Furthermore, in step 303, when the pressure value of the evaporator circuit is detected to exceed the preset pressure range, the specific implementation process is as follows:

[0118] When a low-pressure fault is detected in the evaporator circuit, the backup compressor is turned on and the main compressor is turned off; when a high-pressure fault is detected in the evaporator circuit, the backup compressor is turned on and the main compressor is turned off.

[0119] The aforementioned low-pressure and high-pressure faults are determined based on the pressure that the evaporator circuit can withstand.

[0120] Steps 301-303 are used to control the switching between the main compressor and the standby compressor. This ensures that if the main compressor fails, the standby compressor can start as quickly as possible to guarantee the normal operation of the refrigeration equipment. Steps 304 and 305 balance the overall operating time of the two compressors, preventing compressor failure due to excessive operating time. The advantage of this control method is that it reduces the probability of compressor failure, ensuring the refrigeration equipment can continue to operate normally even if one compressor fails, thus improving the stability of the refrigeration equipment.

[0121] In an optional embodiment, to prevent the pipe temperature in the refrigeration circuit from being too low, causing condensation on the pipes, the control method further includes:

[0122] The system monitors the coolant temperature. When the coolant temperature falls below the set temperature, it checks whether the circulation pump and compressor are running. If the circulation pump is running but the compressor is not, the heater is activated until the coolant temperature is above the set temperature. When the coolant temperature is below the set temperature, it indicates that the plate-type heat dissipation circuit has met the coolant's cooling requirements, and the compressor generally will not start in this state. If the circulation pump is not running when the coolant temperature is below the set temperature, the heater will not activate to prevent direct heating of the pipes and potential damage.

[0123] like Figure 7 As shown, when the coolant temperature is lower than the set temperature, the heater is activated to prevent condensation in the cooling circuit. The set temperature is higher than or close to the valve hall dew point temperature. The valve hall refers to the space where the cooling circuit pipes are arranged. When the coolant temperature is lower than the valve hall dew point temperature, the temperature difference between the pipes and the valve hall can easily cause condensation in the pipes, which can damage the pipes and affect the stability of the refrigeration equipment.

[0124] In this embodiment, the control method further includes the determination of sensor faults: when the sampling signal sent by the sensor is outside the preset range, it is determined that the sensor has malfunctioned; in order to prevent false judgment of sensor fault when the sensor sampling signal is at the boundary value, it is necessary to set a delay time for sensor fault determination; in order to prevent false alarm judgment during sensor power-on, it is necessary to set a delay time for sensor determination.

[0125] Specifically, the refrigeration equipment is also equipped with multiple temperature sensors, pressure sensors, and flow sensors. When a sensor malfunctions, a sensor malfunction alarm is issued. The sensors generally use a 4-20mA signal as the sampling signal. When the sensor's sampling signal is not in the 4-20mA range, it is determined that the sensor has malfunctioned.

[0126] Some sensors may detect values ​​that are close to the lower or upper limits when the refrigeration equipment is running. In such cases, false alarms may occur due to sensor malfunctions. Therefore, it is necessary to set a delay time for sensor malfunction detection based on the type of sensor and the operating conditions of the refrigeration equipment.

[0127] After troubleshooting a sensor fault, when the sensor is reset, a delay is set to prevent false alarms in flow, pressure, or temperature caused by signal jitter during the sensor power-on process. For example, a 20-second delay is set for flow sensors, and a 10-second delay is set for pressure and temperature sensors.

[0128] The delay time refers to the time after which an abnormal sampling signal is received before a sensor is considered to have malfunctioned. If the sampling signal emitted by the sensor is normal during the delay period, the sensor is considered to be without fault.

[0129] like Figure 8 As shown, when the temperature sensor measuring the coolant temperature is a coolant temperature sensor, if the number of times the coolant temperature sensor's sampling signal is outside the 4-20mA range is more than once, after a two-second delay, it is determined that the coolant temperature sensor has malfunctioned, a sensor fault alarm is sent, and the coolant temperature value is set to 16℃. When the plate heat exchanger circuit is operating, and the coolant temperature sensor's sampling signal is within the 4-20mA range, if the coolant temperature is higher than the set high temperature alarm limit, a high water supply temperature alarm is issued after a two-second delay; if the coolant temperature is higher than the set excessively high temperature alarm limit, an excessively high water supply temperature alarm is issued after a two-second delay; if the coolant temperature is lower than the set low temperature alarm limit, a low water supply temperature alarm is issued after a two-second delay.

[0130] Example 2:

[0131] Based on the control method of Embodiment 1 above, this embodiment of the invention also provides a control system for a redundant dual-mode refrigeration device. The control system includes a PLC controller, a first sensor, a first solenoid valve, and a second solenoid valve, used to execute the control method for the redundant dual-mode refrigeration device described in Embodiment 1, combined with... Figure 3a and Figure 3b The controlled redundant dual-mode refrigeration equipment includes: a first refrigeration circuit, a second refrigeration circuit, a cooling circuit, and a three-way valve. The inlet of the three-way valve is connected to the cooling circuit, the first outlet of the three-way valve is connected to the first refrigeration circuit, and the second outlet of the three-way valve is connected to the second refrigeration circuit. The three-way valve is used to circulate refrigerant to the first refrigeration circuit or the second refrigeration circuit.

[0132] The first temperature sensor is installed in the cooling circuit to monitor the temperature of the coolant in the cooling circuit; the first solenoid valve is installed in the first refrigeration circuit to turn the first refrigeration circuit off or on; the second solenoid valve is installed in the second refrigeration circuit to turn the second refrigeration circuit off or on.

[0133] The PLC control module is connected to the first temperature sensor, the first solenoid valve, the second solenoid valve, and the three-way valve respectively. The PLC control module is used to receive the coolant temperature monitored by the first temperature sensor and adjust the three-way valve according to the coolant temperature.

[0134] If the coolant temperature is greater than the first temperature threshold, the PLC control module controls the second solenoid valve to start the second refrigeration circuit and adjusts the three-way valve to connect the inlet and the second outlet so as to absorb the heat of the coolant through the second refrigeration circuit.

[0135] If the coolant temperature is not greater than the first temperature threshold, the PLC control module is used to detect the external water temperature of the first refrigeration circuit and adjust the conduction circuit of the three-way valve according to the external water temperature to selectively dissipate heat through the first refrigeration circuit or the second refrigeration circuit.

[0136] In order to adjust the three-way valve according to the outside water temperature, the control system further includes a second temperature sensor; the second temperature sensor is arranged in the first refrigeration circuit to monitor the outside water temperature; the PLC control module is also connected to the second temperature sensor to obtain the outside water temperature and adjust the three-way valve according to the outside water temperature.

[0137] When the coolant temperature is not greater than the first temperature threshold and the outside water temperature is not greater than the second temperature threshold, the PLC control module is used to start the first refrigeration circuit and adjust the three-way valve to connect the inlet and the first outlet, so as to absorb the heat of the coolant through the first refrigeration circuit.

[0138] When the coolant temperature is not greater than the first temperature threshold and the outside water temperature is greater than the second temperature threshold, the PLC control module is used to start the second refrigeration circuit and adjust the three-way valve to connect the inlet and the second outlet, so that the coolant flows to the second refrigeration circuit and dissipates heat through the second refrigeration circuit.

[0139] The first refrigeration circuit is a plate heat exchanger circuit, and the second refrigeration circuit is an evaporator circuit. The plate heat exchanger circuit includes a plate heat exchanger, and the evaporator circuit includes an evaporator and a compressor. The cooling circuit includes a circulating pump and a heater. The coolant in the cooling circuit can exchange heat with the refrigerant in the evaporator circuit or the external water in the plate heat exchanger circuit. 。

[0140] Normally, a plate heat exchanger circuit is used to cool the coolant. Only when the plate heat exchanger circuit using external water to cool the coolant cannot meet the heat dissipation requirements will an evaporator circuit be used to cool the coolant. This is only done when the coolant temperature or the external water temperature is too high. This reduces the usage time of the evaporator circuit, reduces the probability of evaporator circuit failure, and ensures the cooling efficiency of the entire refrigeration equipment.

[0141] like Figure 9As shown, when the coolant temperature is less than 28°C, if the outside water temperature is greater than 20°C, the second solenoid valve is opened and the first solenoid valve is closed to open the evaporator circuit and close the plate heat exchanger circuit. The three-way valve then activates, connecting the evaporator circuit and the cooling circuit. The evaporator circuit acts as a heat dissipation circuit to cool the coolant, while the plate heat exchanger circuit acts as a bypass circuit. If the outside water temperature is less than 20°C, the first solenoid valve is opened and the second solenoid valve is closed to open the plate heat exchanger circuit and close the evaporator circuit. The three-way valve then reverses its operation to connect the plate heat exchanger circuit and the cooling circuit, using the plate heat exchanger circuit as a heat dissipation circuit to cool the coolant, while the evaporator circuit acts as a bypass circuit. The refrigeration equipment uses a three-phase 380V AC power supply with reliable grounding to ensure stable and safe system operation. The control system uses a separately configured control power supply, converted from a DC switching power supply, and is isolated from the AC power supply used by the refrigeration equipment.

[0142] The circulating pump, compressor, heater, etc. are equipped with short circuit, overcurrent, overvoltage, voltage drop, phase protection and fault information monitoring. When a fault occurs, the fault information is uploaded to the PLC control module.

[0143] The control system also includes a soft starter. When starting the compressor, the motor speed can be controlled by the soft starter to extend the start-up time, smooth the current, and reduce the impact load caused by the motor starting, thereby achieving a soft start for the compressor.

[0144] In order to monitor the pressure in the second refrigeration circuit and the flow rate in the cooling circuit, the control system also includes a pressure sensor and a flow sensor.

[0145] The pressure sensor is installed in the second refrigeration circuit to monitor the pressure within the second refrigeration circuit; the flow sensor is installed in the cooling circuit to monitor the flow rate of the coolant in the cooling circuit.

[0146] This allows for the selective use of a backup circulation pump based on the status of the main circulation pump, the flow rate of the coolant, and / or the pressure of the coolant, and the selective use of a standby compressor based on the operating condition of the main compressor and / or the coolant temperature of the cooling circuit.

[0147] When the measured value of any instrument, such as the pressure sensor, temperature sensor, or flow sensor, exceeds the warning limit, the PLC control module sends a warning signal to the remote controller to remind the operators to pay attention; when the measured value of the instrument exceeds the trip limit, a trip signal is sent to shut down the refrigeration equipment in an emergency.

[0148] Specifically, the principle of the control system is as follows: Figure 10As shown, the signal input terminal of the PLC control module accepts various signal inputs, such as compressor status information sent by the compressor, circulation pump status information sent by the circulation pump, external water temperature, ambient temperature, coolant temperature, evaporator circuit temperature detected by temperature sensors, and coolant flow information detected by flow sensors. Based on the signal inputs, the module controls the operation of equipment such as the circulation pump, compressor, heater, and three-way valve. It can also manually control equipment such as the circulation pump and compressor in the refrigeration equipment through a local controller. Furthermore, it sends various information obtained from the signal input terminal to a remote controller to achieve real-time monitoring of the operating status of the refrigeration equipment.

[0149] The control system can control the refrigeration equipment in manual or automatic mode. Figure 11 As shown, during the execution of manual and automatic modes, the state of the control system can be divided into initialization state, manual state, local automatic state, remote automatic state, prohibited operation state, and state switching lock display, etc.

[0150] When controlling refrigeration equipment in manual mode, the equipment can be operated through a local controller or a remote controller, such as starting or stopping the compressor, heater, and circulation pump. Manual mode is generally used during system maintenance and debugging.

[0151] In automatic control mode, the control system monitors the operating status of the refrigeration equipment and detects system faults according to predetermined parameters. The PLC control module automatically controls the coolant temperature, flow rate, and pressure, and provides timely warnings and activates warning indicator lights when refrigeration equipment parameters exceed limits. When parameters are severely exceeded and may affect the operational safety of the cooled components, a comprehensive fault alarm indicator light is activated, automatically issuing a comprehensive fault alarm. When the PLC control module receives a stop signal during operation, it stops the refrigeration equipment at a predetermined time; when the stop signal fails, the PLC control module automatically resumes the operation of the refrigeration equipment. In automatic control mode, the PLC control module also automatically controls equipment such as compressors, heaters, and circulating pumps based on actual operating conditions, such as coolant temperature, flow rate, and external water temperature.

[0152] To remotely control the refrigeration equipment, the control system also implements remote control communication control through the PLC module. The remote controller can input remote start and remote stop signals for the refrigeration equipment to the PLC control module to remotely shut down and start the refrigeration equipment. The PLC control module outputs warning information, alarm information, and refrigeration equipment operating status information to the remote controller to achieve remote monitoring of the refrigeration equipment.

[0153] The remote controller can display the status of electromechanical units such as the circulation pump, compressor, heater, and solenoid valve on a display. The remote controller can also display the status information of refrigeration equipment such as coolant flow rate, coolant temperature, external water temperature, and evaporator circuit pressure in the cooling circuit.

[0154] Early warning information is used to provide abnormal warning signals for refrigeration equipment, alerting users to faults that do not affect the normal operation of the equipment. Through different warning messages, problems and potential issues in the operation of refrigeration equipment can be detected and addressed promptly, maintaining the equipment in good operating condition. Warning messages are usually caused by minor faults in the refrigeration equipment, which can generally be addressed while the equipment is running.

[0155] Alarm information is used to provide fault signals for refrigeration equipment, indicating that under this fault, the refrigeration equipment can no longer be used normally and the gate must be opened to shut down the refrigeration equipment. At this time, the equipment is in a serious fault state.

[0156] Combination Figure 12 In this embodiment, the control system also communicates with the refrigeration equipment via Modbus and Ethernet interfaces to monitor the status of the refrigeration equipment and obtain alarm information from the refrigeration equipment.

[0157] The specific implementation method of the redundant dual-mode refrigeration equipment control method is described in Example 1 and will not be repeated here.

[0158] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A control method for a redundant dual-mode refrigeration device, characterized in that, The redundant dual-mode refrigeration equipment includes a first refrigeration circuit, a second refrigeration circuit, a cooling circuit, and a three-way valve. The inlet of the three-way valve is connected to the cooling circuit, the first outlet of the three-way valve is connected to the first refrigeration circuit, and the second outlet of the three-way valve is connected to the second refrigeration circuit. The first refrigeration circuit is a plate heat exchanger circuit, and the second refrigeration circuit is an evaporator circuit. The control method includes: Detect the coolant temperature in the cooling circuit; If the coolant temperature is greater than a first temperature threshold, the second refrigeration circuit is activated, and the three-way valve is adjusted to connect the inlet and the second outlet, absorbing heat from the coolant through the second refrigeration circuit; this includes: if the coolant temperature is greater than the first temperature threshold, activating the second refrigeration circuit; adjusting the flow rate through the second refrigeration circuit according to the coolant temperature; gradually reducing the coolant flow rate through the first refrigeration circuit and gradually increasing the coolant flow rate through the second refrigeration circuit within a predetermined time period; and closing the first refrigeration circuit after all the coolant has passed through the second refrigeration circuit. If the coolant temperature is not greater than the first temperature threshold, the external water temperature of the first refrigeration circuit is detected, and the conduction circuit of the three-way valve is adjusted according to the external water temperature to selectively dissipate heat through the first refrigeration circuit or the second refrigeration circuit.

2. The control method according to claim 1, characterized in that, The step of detecting the external water temperature of the first refrigeration circuit if the coolant temperature is not greater than a first temperature threshold, and adjusting the conduction circuit of the three-way valve according to the external water temperature to selectively dissipate heat through the first refrigeration circuit or the second refrigeration circuit includes: If the coolant temperature is not greater than the first temperature threshold, then the external water temperature of the first refrigeration circuit is detected; If the outside water temperature is not greater than the second temperature threshold, start the first refrigeration circuit and adjust the three-way valve to connect the inlet and the first outlet, so as to absorb the heat of the coolant through the first refrigeration circuit. If the external water temperature is greater than the second temperature threshold, the second refrigeration circuit is activated, and the three-way valve is adjusted to connect the inlet and the second outlet, so that the coolant flows to the second refrigeration circuit for heat dissipation.

3. The control method according to claim 1, characterized in that, The plate heat exchange circuit includes a plate heat exchanger, the evaporator circuit includes an evaporator and a compressor, the cooling circuit includes a circulating pump and a heater, and the coolant in the cooling circuit can exchange heat with the refrigerant in the evaporator circuit or the external water in the plate heat exchange circuit.

4. The control method according to claim 3, characterized in that, The circulating pump includes a main circulating pump and a standby circulating pump, and the compressor includes a main compressor and a standby compressor. When the second refrigeration circuit is operating, the control method further includes: The backup circulation pump may be used selectively depending on the status of the main circulation pump, the flow rate of the coolant, and / or the pressure of the coolant. The standby compressor may be selectively used based on the operating status of the main compressor and / or the coolant temperature of the cooling circuit.

5. The control method according to claim 4, characterized in that, The selective use of a backup circulation pump based on the status of the main circulation pump, the flow rate of the coolant, and / or the pressure of the coolant includes: When the coolant flow rate is detected to be lower than the set flow rate threshold and an alarm signal is received, the backup circulation pump is turned on and the main circulation pump is turned off. When the coolant pressure is detected to be lower than the set pressure threshold and an alarm signal is received, the backup circulation pump is turned on and the main circulation pump is turned off. When overcurrent is detected in the main circulation pump, the backup circulation pump is turned on and the main circulation pump is turned off. After the main circulation pump has been operating for a preset time, the backup circulation pump is turned on and the main circulation pump is turned off. When the refrigeration equipment is turned on, the pump with the shortest cumulative running time is selected for operation first, and the currently running pump is used as the main circulation pump.

6. The control method according to claim 4, characterized in that, The compressor employs a configuration of one main compressor and one standby compressor. The standby compressor is selectively used based on the operating status of the main compressor and / or the coolant temperature in the cooling circuit, including: When the coolant temperature is detected to be higher than the set temperature threshold and an alarm signal is received, the backup compressor is turned on and the main compressor is turned off. When a failure is detected in the main compressor, the backup compressor is activated and the main compressor is shut down. When the pressure value of the evaporator circuit is detected to exceed the preset pressure range, the backup compressor is turned on and the main compressor is turned off. After the main compressor has been operating for a preset time, the standby compressor is turned on and the main compressor is turned off. When the refrigeration equipment is turned on, the compressor with the shortest cumulative running time is selected first, and the currently running compressor is used as the main compressor.

7. A control system for a redundant dual-mode refrigeration equipment, characterized in that, The control system of the redundant dual-mode refrigeration equipment includes a PLC control module, a first temperature sensor, a first solenoid valve, and a second solenoid valve, and is used to execute the control method of the redundant dual-mode refrigeration equipment according to any one of claims 1 to 6. The controlled redundant dual-mode refrigeration equipment includes: a first refrigeration circuit, a second refrigeration circuit, a cooling circuit, and a three-way valve. The inlet of the three-way valve is connected to the cooling circuit, the first outlet of the three-way valve is connected to the first refrigeration circuit, and the second outlet of the three-way valve is connected to the second refrigeration circuit. The three-way valve is used to circulate refrigerant to the first refrigeration circuit or the second refrigeration circuit. The first temperature sensor is installed in the cooling circuit to monitor the temperature of the coolant in the cooling circuit; The first solenoid valve is installed in the first refrigeration circuit and is used to close or start the first refrigeration circuit. The second solenoid valve is installed in the second refrigeration circuit and is used to shut down or start the second refrigeration circuit; The PLC control module is connected to the first temperature sensor, the first solenoid valve, the second solenoid valve and the three-way valve respectively. The PLC control module is used to receive the coolant temperature monitored by the first temperature sensor and adjust the three-way valve according to the coolant temperature. If the coolant temperature is greater than the first temperature threshold, the PLC control module controls the second solenoid valve to start the second refrigeration circuit and adjusts the three-way valve to connect the inlet and the second outlet so as to absorb the heat of the coolant through the second refrigeration circuit. If the coolant temperature is not greater than the first temperature threshold, the PLC control module is used to detect the external water temperature of the first refrigeration circuit and adjust the conduction circuit of the three-way valve according to the external water temperature to selectively dissipate heat through the first refrigeration circuit or the second refrigeration circuit.

8. The control system according to claim 7, characterized in that, The control system further includes a second temperature sensor; the second temperature sensor is arranged in the first refrigeration circuit and is used to monitor the temperature of the external water. The PLC control module is also connected to the second temperature sensor to obtain the temperature of the external water and adjust the three-way valve according to the temperature of the external water. When the coolant temperature is not greater than the first temperature threshold and the outside water temperature is not greater than the second temperature threshold, the PLC control module is used to start the first refrigeration circuit and adjust the three-way valve to connect the inlet and the first outlet, so as to absorb the heat of the coolant through the first refrigeration circuit. When the coolant temperature is not greater than the first temperature threshold and the outside water temperature is greater than the second temperature threshold, the PLC control module is used to start the second refrigeration circuit and adjust the three-way valve to connect the inlet and the second outlet, so that the coolant flows to the second refrigeration circuit and dissipates heat through the second refrigeration circuit.

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