Variable orifice plate throttling device for large water-cooling air conditioning unit

Abstract

The technical scheme of the utility model discloses a variable orifice plate throttling device for a large-scale water-cooling air conditioning unit, which comprises an electric three-way shunting regulating valve, a throttling orifice plate A, a throttling orifice plate B, a condenser, an evaporator, a compressor and a controller, an outlet of the condenser is connected with an inlet of the evaporator through the electric three-way flow dividing adjusting valve, an outlet of the evaporator is connected with an inlet of the compressor, the throttling orifice A and the throttling orifice B are arranged between the electric three-way flow dividing adjusting valve and the evaporator in parallel, and the controller is connected with the condenser, the evaporator and the electric three-way flow dividing adjusting valve. Through cooperation of the throttling orifice plate A, the throttling orifice plate B and the electric three-way flow dividing adjusting valve, the throttling capacity requirement of the large water-cooling air conditioning unit during large-load operation and precise throttling control during partial-load operation are both met.

Description

TECHNICAL FIELD

[0001] The utility model belongs to throttling technical field, more particularly to a big water -cooled air conditioning unit with variable orifice plate throttling system. BACKGROUND

[0002] The throttling system of large water-cooled air conditioning unit, such as large-capacity centrifugal unit, cannot generally consider the precise regulation of small and large loads. Since the design and selection of the throttling system are based on the calculation of full load operation of the unit, the throttling system cannot be accurately controlled when the unit is running at small load, and it is difficult to meet the operation requirements of the unit working condition. The current air conditioning unit throttling control methods mainly include the following: (1) thermal expansion valve throttling, the thermal expansion valve senses the superheat degree change of the evaporator outlet through the temperature sensing bag, and automatically adjusts the opening degree of the valve to control the refrigerant flow, but the precision is low, the adjustment capacity is small, the large unit cannot be used, and it cannot be linked with the automatic control system of the unit; (2) throttling orifice plate, the throttling orifice plate is composed of a circular metal plate and a plurality of uniformly distributed small holes, the high-pressure liquid refrigerant flow rate is sharply increased through the small holes, and the pressure is rapidly reduced to achieve throttling and pressure reduction, but the adjustment range is narrow, and only within a certain range can throttling and pressure reduction be achieved, and the large unit cannot be normally adjusted when deviating from the design working condition; (3) electronic expansion valve throttling, the electronic expansion valve uses a stepper motor to drive the valve needle to rotate to control the opening degree of the valve to adjust the refrigerant flow, it receives the electric signal from the air conditioning control system, and accurately controls the opening degree of the valve according to the temperature, pressure and other parameters of the evaporator, the adjustment of the opening degree can be continuous, and rapid response can be realized, but the cost is high, and there is no product available for large-capacity units; (4) electric regulating valve and throttling orifice plate throttling, an electric regulating valve is installed before the throttling orifice plate to increase the adjustment range of the unit throttling system within a certain range, but due to the limited adjustment capacity of the electric regulating valve, only the throttling capacity of the liquid pipe can be roughly controlled, especially for large units, since the orifice plate and the electric regulating valve are selected based on the full load operation of the unit, the throttling effect is difficult to control when the unit is running at small load.

[0003] Patent CN 201811507 U discloses an orifice plate throttling device, including an orifice plate and solenoid valves connected in series. The solenoid valves include a first solenoid valve, a second solenoid valve, and a third solenoid valve. The orifice plate includes a first orifice plate, a second orifice plate, and a third orifice plate. The first solenoid valve and the first orifice plate are connected in series to form a first branch, the second solenoid valve and the second orifice plate are connected in series to form a second branch, and the third solenoid valve and the third orifice plate are connected in series to form a third branch. The first, second, and third branches are connected in parallel, which can perform segmented flow regulation over a wide flow range, achieving segmented regulation within a wide flow range. However, the solenoid valves can only perform on / off functions, which can cause system fluctuations when switching pipelines, resulting in system instability during actual operation. Therefore, there is a need to develop a variable orifice plate throttling device that can meet the throttling capacity requirements of large water-cooled air conditioning units operating under high load and precise throttling control during partial load operation. Utility Model Content

[0004] To address the existing technical problems, this utility model provides a variable orifice plate throttling device for large water-cooled air conditioning units. Through the cooperation of orifice plate A, orifice plate B, and electric three-way diversion regulating valve, it achieves precise throttling control that meets the throttling capacity requirements of large water-cooled air conditioning units under high load operation and under partial load operation.

[0005] The technical solution of this utility model is: a variable orifice plate throttling device for a large water-cooled air conditioning unit, comprising an electric three-way diversion regulating valve, a throttling orifice plate A, a throttling orifice plate B, a condenser, an evaporator, a compressor, and a controller. The compressor outlet is connected to the condenser inlet, the condenser outlet is connected to the evaporator inlet through the electric three-way diversion regulating valve, and the evaporator outlet is connected to the compressor inlet. The throttling orifice plate A and the throttling orifice plate B are arranged in parallel between the electric three-way diversion regulating valve and the evaporator. The controller is connected to the condenser, the evaporator, and the electric three-way diversion regulating valve.

[0006] Furthermore, the input end of the electric three-way diverter valve is connected to the condenser, one output end is connected to orifice plate A, and the other output end is connected to orifice plate B. The medium flows in from the input port AB of the electric three-way diverter valve and flows out from the two output ports A and B. When the electric three-way diverter valve is fully open, the medium flows in from port AB and flows out only from port A; when the electric three-way diverter valve is fully closed, the medium flows in from port AB and flows out only from port B; when the electric three-way diverter valve is in a certain intermediate position, the medium flows in from port AB and flows out from ports A and B proportionally.

[0007] Furthermore, the flow rate of the orifice plate A is adapted to the 100% load capacity of the air conditioning unit, and the flow rate of the orifice plate B is adapted to the 30%~50% load capacity of the air conditioning unit.

[0008] Furthermore, a liquid level sensor is installed on the condenser, and the liquid level sensor is connected to the controller, transmitting the liquid level sensor data to the controller; the evaporation temperature and the outlet water temperature of the evaporator are transmitted to the controller; the controller controls the opening degree of the electric three-way diversion regulating valve.

[0009] This utility model discloses a variable orifice plate throttling device for a large water-cooled air conditioning unit. During operation, a liquid level sensor on the condenser monitors the refrigerant level L in the condenser in real time and transmits L to the controller. Based on existing technology, the optimal operating liquid level range L1~Lh of the condenser is confirmed through heat exchanger design and selection calculations and test bench debugging, serving as an auxiliary control target value. The optimal heat exchange temperature difference Td0 of the evaporator is confirmed through heat exchanger design and selection calculations. The difference Td between the evaporation temperature and the outlet water temperature of the evaporator is detected and transmitted to the controller. When the actual load of the unit is >80%, the compressor operates at full load or near full load, requiring a large refrigerant circulation volume. The controller fully opens the electric three-way diversion regulating valve, allowing all the refrigerant to enter the evaporator after being throttled through the orifice plate A. When the unit's actual load is 50% ≤ Actual Load ≤ 80%, the controller keeps the electric three-way diverter valve opening above the set value (e.g., 50%). At this time, most of the refrigerant enters the evaporator through orifice plate A, and a small portion enters through orifice plate B. Simultaneously, the controller adjusts the opening of the electric three-way diverter valve based on the refrigerant level L in the condenser to maintain the condenser level within the optimal operating range L1~Lh. When the unit's actual load is < 50%, the controller adjusts the electric three-way diverter valve opening below the set value (e.g., 50%). At this time, most of the refrigerant enters the evaporator through orifice plate B, and a small portion enters through orifice plate A. Simultaneously, the controller adjusts the opening of the electric three-way diverter valve based on the Td value to ensure the evaporator's heat exchange effect. Furthermore, if the condenser level L is lower than the safety control level, the controller will periodically force the electric three-way diverter valve opening to decrease by 5% to ensure the cooling effect of the compressor system.

[0010] The beneficial effects achieved by adopting the above technical solution are as follows: By connecting orifice plates A and B of different specifications in parallel and combining them with an electric three-way flow divider valve, different refrigerant orifice plates can be selected for throttling under different load conditions of the unit, thus taking into account both the throttling capacity requirements of large water-cooled air conditioning units under high load operation and precise throttling control under partial load operation. The structure is simple, the cost is low, and the throttling effect is good. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of this utility model;

[0012] Figure 2 This is a schematic diagram of the structure of the electric three-way diverter valve of this utility model.

[0013] In the diagram, 1 is an electric three-way flow control valve; 2 is an orifice plate A; 3 is an orifice plate B; 4 is a condenser; 5 is an evaporator; 6 is a compressor; 7 is a controller; and 8 is a liquid level sensor. Detailed Implementation

[0014] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. Example

[0015] Reference Figures 1-2 A variable orifice plate throttling device for a large water-cooled air conditioning unit includes an electrically operated three-way diverter valve 1, a throttling orifice plate A 2, a throttling orifice plate B 3, a condenser 4, an evaporator 5, a compressor 6, and a controller 7. The outlet of the compressor 6 is connected to the inlet of the condenser 4, and the outlet of the condenser 4 is connected to the inlet of the evaporator 5 through the electrically operated three-way diverter valve 1. The outlet of the evaporator 5 is connected to the inlet of the compressor 6. The throttling orifice plates A 2 and B 3 are arranged in parallel between the electrically operated three-way diverter valve 1 and the evaporator 5. The controller 7 is connected to the condenser 4, the evaporator 5, and the electrically operated three-way diverter valve 1.

[0016] Furthermore, the input end of the electric three-way diverter valve 1 is connected to the condenser 4, one output end is connected to the orifice plate A 2, and the other output end is connected to the orifice plate B 3. For example... Figure 2 The medium shown flows into the electric three-way diverter valve 1 from the input port AB and flows out from the two output ports A and B. Output port A is connected to orifice plate A 2, and output port B is connected to orifice plate B 3. When the electric three-way diverter valve 1 is fully open, the medium flows in from port AB and flows out only from port A; when the electric three-way diverter valve 1 is fully closed, the medium flows in from port AB and flows out only from port B; when the electric three-way diverter valve 1 is in a certain intermediate position, the medium flows in from port AB and flows out from ports A and B proportionally.

[0017] Furthermore, the flow rate of the orifice plate A2 is adapted to the 100% load capacity of the air conditioning unit, and the flow rate of the orifice plate B3 is adapted to the 30%~50% load capacity of the air conditioning unit. By selecting the specifications of the orifice plate according to the different load capacities of the unit, and cooperating with the electric three-way diverter valve 1, the throttling requirements of the unit during full-load operation can be met, and precise throttling control can be performed when the air conditioning unit is operating at partial load.

[0018] Furthermore, a liquid level sensor 8 is installed on the condenser 4, and the liquid level sensor 8 is connected to the controller 7. The liquid level sensor 8 transmits data to the controller 7. The evaporation temperature and the outlet water temperature of the evaporator 5 are transmitted to the controller 7. The controller 7 controls the opening degree of the electric three-way diversion regulating valve 1.

[0019] In operation of the variable orifice plate throttling device for a large water-cooled air conditioning unit, the liquid level sensor 8 on the condenser 4 monitors the refrigerant level L in the condenser 4 in real time and transmits the liquid level L to the controller 7. Based on existing technology, the optimal operating liquid level range L1~Lh of the condenser 4 is confirmed through heat exchanger design and selection calculations and test bench debugging as an auxiliary control target value. Based on existing technology, the optimal heat exchange temperature difference Td0 of the evaporator 5 is confirmed through heat exchanger design and selection calculations. The evaporation temperature and outlet water temperature of the evaporator 5 are detected and transmitted to the controller 7 to obtain the difference Td between the evaporation temperature and the outlet water temperature of the evaporator 5. When the actual load of the unit is >80%, the compressor 6 operates at full load or near full load, requiring a large refrigerant circulation volume. The controller 7 controls the electric three-way diversion regulating valve 1 to fully open, allowing all the refrigerant to enter the evaporator 5 after being throttled through the orifice plate A2. When the unit is at 50 ≤ actual load ≤ 80%, the controller 7 controls the electric three-way diversion regulating valve 1 to operate at an opening above the set value (e.g., 50%). At this time, most of the refrigerant enters the evaporator 5 through the orifice plate A2, and a small portion of the refrigerant enters the evaporator 5 through the orifice plate B3. At the same time, the opening of the electric three-way diversion regulating valve 1 is adjusted according to the liquid level L of the refrigerant in the condenser 4, so that the liquid level in the condenser 4 is maintained within the optimal working liquid level range L1~Lh. When the actual load of the unit is less than 50%, the controller 7 adjusts the opening of the electric three-way diversion regulating valve 1 to operate below the set value (e.g., 50%). At this time, most of the refrigerant enters the evaporator 5 through the orifice plate B 3, and a small portion of the refrigerant enters the evaporator 5 through the orifice plate A 2. At the same time, the opening of the electric three-way diversion regulating valve 1 is corrected according to the Td value to ensure the heat exchange effect of the evaporator 5. Meanwhile, if the liquid level L of the condenser 4 is lower than the safety control liquid level, the opening of the electric three-way diversion regulating valve 1 will be forcibly closed by 5% periodically to ensure the cooling effect of the compressor 6 system.

Claims

1. A variable orifice plate throttling device for a large water-cooled air conditioning unit, characterized by: The application relates to an electric three-way shunt regulating valve (1), a throttle orifice plate A (2), a throttle orifice plate B (3), a condenser (4), an evaporator (5), a compressor (6) and a controller (7), wherein the compressor (6) is connected with the condenser (4) at the outlet, the condenser (4) is connected with the evaporator (5) at the outlet through the electric three-way shunt regulating valve (1), the evaporator (5) is connected with the compressor (6) at the inlet, the throttle orifice plate A (2) and the throttle orifice plate B (3) are arranged in parallel between the electric three-way shunt regulating valve (1) and the evaporator (5), and the controller (7) is connected with the condenser (4), the evaporator (5) and the electric three-way shunt regulating valve (1).

2. The variable orifice plate throttling device for a large water-cooled air conditioning unit according to claim 1, characterized in that: The input end of the electric three-way shunt regulating valve (1) is connected with the condenser (4), one output end is connected with the throttle orifice plate A (2), and the other output end is connected with the throttle orifice plate B (3).

3. A variable orifice plate throttling device for a large water-cooled air conditioning unit according to claim 1 or 2, characterized in that: The flow of the throttle orifice plate A (2) is matched with 100% load capacity of the air conditioning unit, and the flow of the throttle orifice plate B (3) is matched with 30%-50% load capacity of the air conditioning unit.

4. The variable orifice plate throttling device for a large water-cooled air conditioning unit according to claim 1, characterized in that: A liquid level sensor (8) is arranged on the condenser (4), the liquid level sensor (8) is connected with the controller (7), data of the liquid level sensor (8) is transmitted to the controller (7), the evaporation temperature of the evaporator (5) and the outlet water temperature of the evaporator (5) are transmitted to the controller (7), and the controller (7) controls the opening degree of the electric three-way shunt regulating valve (1).

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