Compressor performance testing device with rapid and stable working conditions

Abstract

The invention discloses a compressor performance testing device capable of rapidly stabilizing working conditions, and relates to the technical field of compressor performance testing. The system comprises a test device and a test system in communication control connection with the test device, and the test device comprises an oil separation assembly and a refrigerant assembly; the oil separation assembly comprises an oil component, the oil component is connected with an oil flow meter and a gas path total flow meter through a tee joint, and the other end of the oil flow meter is connected with an oil cooler in series through an oil path pipeline. Through the arrangement of the refrigerant assembly, when a high-temperature and high-pressure gaseous refrigerant is discharged from the outlet of the tested compressor, one part of the high-temperature and high-pressure refrigerant is directly poured into the mixing box through the tee joint, and the other part of the high-temperature and high-pressure refrigerant is condensed by the condenser to become a liquid low-temperature and high-pressure refrigerant to enter the mixing box; the liquid refrigerant and the gas refrigerant are mixed, and the mixing proportion can be adjusted through the two adjusting valves respectively, so that the requirements of test working conditions are met.

Description

Technical Field

[0001] The invention belongs to the technical field of compressor performance testing, and in particular relates to a compressor performance testing device with rapid and stable working conditions. Background Art

[0002] As the core component of the automobile air conditioning system, the performance and life of the automobile air conditioning compressor directly affect its use efficiency, and major automobile parts manufacturers are continuously increasing their R&D investment. Due to the particularity of automobile operation and use environment, the start-stop frequency, working conditions and speed variation of automobile air conditioning compressors are greater than those of household air conditioning compressors, so it is particularly important to test non-steady-state working conditions, variable speed and rapid performance.

[0003] At present, many scientific research institutions have special compressor durability test benches and performance test benches, but there are few studies on comprehensive multi-span test benches. The current mainstream performance test method is the second refrigerant calorimeter method, such as Figure 1 As shown in the figure, it is the principle diagram of the performance test of the second refrigerant calorimeter method. When the second refrigerant calorimeter method is used for testing, due to the large space in the calorimeter tank cavity, the secondary refrigerant and the tank cavity space cause large thermal inertia, which will cause the compressor suction temperature to stabilize for too long; the compressor exhaust pressure is also controlled by adjusting the amount of cold and hot water in the condenser, and there will also be large thermal inertia. Therefore, when the second refrigerant method is used to test the performance, the working condition stability will generally be longer, and a complete test time may exceed two hours, which is not convenient for real-time tracking of compressor performance changes, and it is impossible to cope with non-steady-state working conditions and variable speed working conditions. With the further upgrading of the evaluation requirements of various air-conditioning accessories and automotive thermal management systems, the test process is required to be as comprehensive and objective as possible to reduce the possibility of human intervention, and at the same time, it is upgraded from the previous static evaluation to a dynamic working condition evaluation. However, due to the current level of the test equipment industry, many dynamic simulations and tests cannot be widely promoted due to technical and cost reasons.

[0004] The existing compressor performance testing device cannot dynamically simulate a variety of working conditions to test the compressor. The testing time is long and it is not convenient to understand the performance changes of the compressor when tested under different working conditions. Therefore, the present invention proposes a compressor performance testing device with fast and stable working conditions. Summary of the invention

[0005] The purpose of the present invention is to provide a compressor performance testing device with fast and stable working conditions, so as to solve the problems that the existing compressor performance testing device cannot dynamically simulate a variety of working conditions to test the compressor, the testing time is long, and it is not convenient to understand the performance changes of the compressor when tested under different working conditions.

[0006] In order to solve the above technical problems, the present invention is achieved through the following technical solutions: The present invention is a device for testing the performance of a compressor with rapid and stable working conditions, comprising a testing device and a testing system that establishes a communication control connection with the testing device, wherein the testing device comprises an oil separation component and a refrigerant component; The oil separation assembly includes an oil separator, which is connected to an oil flow meter and a gas circuit total flow meter through a tee, the other end of the oil flow meter is connected in series with an oil cooler through an oil pipeline, and an oil return flow regulating valve is connected in series to the oil pipeline between the oil flow meter and the oil cooler; The refrigerant component includes an exhaust pressure regulating valve, one end of the exhaust pressure regulating valve is connected to the gas circuit total flow meter, and the other end is connected to the condenser through a refrigerant pipe. The condenser is connected in series with the mixer through the refrigerant pipe, and a liquid circuit flow meter and an intake temperature regulating valve are installed on the refrigerant pipe between the condenser and the mixer; a refrigerant pipe extends outward from the refrigerant pipe between the exhaust pressure regulating valve and the condenser, and the refrigerant pipe is connected to the mixer, and an intake pressure regulating valve is installed on the refrigerant pipe; the mixer outlet and the oil cooler outlet are both connected to the air inlet of the tested compressor, and the air outlet of the tested compressor is connected in series with the oil separator.

[0007] Preferably, the mixer includes a mixing chamber, which is respectively provided with a liquid inlet interface and a liquid outlet interface at the front and rear ends thereof, and a stepper motor is installed on the outer wall of one side of the mixing chamber, the output end of the stepper motor passes through the mixing chamber to the interior thereof, and is fixedly connected to a side surface of a driving gear, and the upper and lower sides of the driving gear are respectively meshed with racks, and the racks are slidably installed on the inner wall of the mixing chamber, and the tooth grooves of the two racks are respectively meshed with two movable gears and a connecting gear, and the connecting gears are staggeredly meshed with a driven gear, and pressure regulating plates are fixedly installed at one end of the driven gear and one end of the movable gear, and the pressure regulating plate installed at one end of the driven gear is staggered with the pressure regulating plate installed at one end of the movable gear, and the maximum adjustment angle of each of the pressure regulating plates does not exceed 30°.

[0008] Preferably, the test system includes a main control module, and a refrigerant circulation module and an oil treatment module of the machine under test which establish communication connection with the main control module; Main control module: used to control the relevant mechanisms of the test equipment according to the instructions of other modules of the test system, and receive the output data of the relevant mechanisms of the test equipment; Refrigerant circulation module of the tested machine: used to control the relevant mechanisms of the refrigerant components in the test equipment, mix the high-temperature and high-pressure gaseous refrigerant at the exhaust end with the supercooled liquid refrigerant according to the test requirement ratio and return it to the suction end of the tested compressor, so as to change the control working conditions of the tested compressor; among which, the control working conditions of the tested compressor include suction temperature, suction pressure and exhaust pressure; Oil processing module: used to control the oil separation component to separate the lubricating oil contained in the refrigerant during the test operation of the tested compressor, while maintaining the lubricating oil temperature; Measurement and control module: used to calculate the opening of each regulating valve and the auxiliary working condition preset by correcting the parameters of the tested compressor and the control working condition parameters. When the tested compressor is turned on, each actuator of the test equipment is adjusted according to the preset output to quickly reach the control working condition; Calculation module: used to calculate the compressor capacity, the theoretical mass flow of the radial compressor under the test conditions and the flow capacity of the regulating valve through the compressor capacity calculation formula combined with the data of the test equipment; the calculated liquid flow value is compared with the test value of the liquid flow meter to verify the accuracy of the test result.

[0009] Preferably, the test system also includes a constant temperature water control module: the condenser water inlet temperature is quickly controlled during the refrigerant circulation process by means of a water pump, a three-way valve and electric heating arranged outside the condenser, thereby quickly controlling the shutdown balance pressure of the start-stop condition; the constant temperature water control module exchanges heat for the condenser during normal operation to ensure that the refrigerant has subcooling before entering the intake temperature regulating valve.

[0010] Preferably, the test system also includes an electrical control unit, which is used for human-computer interaction and automatic experiments, and is composed of a computer unit, a programmable controller, a touch screen and a digital control instrument. The computer unit is used to automatically set and send test conditions, calculate the initial opening of each regulating valve according to the working conditions, and monitor the entire experimental process. At the same time, it collects all data of the test equipment, judges the stability of the working conditions and data, calculates, and outputs complete test data and test reports; when the test working conditions are stable, the output values ​​of each regulating instrument are recorded, and the deviation between the theoretical calculated value and the actual value is calculated for subsequent tests with the same working conditions; the programmable controller is used to program the control logic and alarm action of the test equipment for automatic control; the touch screen is a human-computer interaction interface, and the opening and closing of the test equipment and the alarm prompt are all realized through the touch screen; the digital control instrument controls the suction and exhaust pressure, suction temperature, return oil temperature, return oil flow, ambient temperature and cold water temperature parameters of each circuit of the tested compressor by negative feedback.

[0011] Preferably, the calculation formulas in the calculation module regarding the compressor capacity, the theoretical mass flow of the radial compressor under the test condition, and the flow capacity of the regulating valve include the following contents; The compressor capacity calculation formula includes a refrigerant liquid circuit flow calculation formula, a cooling capacity calculation formula, and a heating capacity calculation formula; The refrigerant liquid circuit flow calculation formula is shown in formula (1): (1); The cooling capacity calculation formula is shown in formula (2): (2); The heating capacity calculation formula is shown in formula (3): (3); in: Heat leakage for mixer; is the theoretical specific enthalpy of the refrigerant entering the tested compressor under basic test conditions; is the specific enthalpy of the evaporated refrigerant leaving the calorimeter; is the measured specific enthalpy of the refrigerant leaving the compressor under test under basic test conditions; The theoretical specific enthalpy of the refrigerant before the evaporator expansion valve in the refrigeration cycle where the tested compressor is located under basic test conditions; is the specific enthalpy of the refrigerant liquid entering the main circuit refrigerant liquid inlet expansion valve; It is the measured specific volume of the refrigerant vapor entering the tested compressor under basic test conditions; is the theoretical specific volume of the refrigerant vapor entering the tested compressor under basic test conditions; The theoretical mass flow rate calculation formula flowing through the tested compressor under known test compressor speed, displacement, volumetric efficiency and test conditions is shown in formula (4): (4); in: is the solvent efficiency of the tested compressor, in units of %; n is the speed of the tested compressor, in units of r / min; is the theoretical displacement of the tested compressor, in units of , v is the suction volume of the tested compressor, in units of ; The calculation formulas for the flow capacity of the regulating valve are shown in equations (5), (6) and (7): (5); (6); (7); in: It is the flow capacity of the suction temperature control valve under the test conditions; It is the flow capacity of the suction pressure regulating valve under the test conditions; is the liquid flow rate in units of , is the gas flow rate, in units of ; is the absolute pressure on the primary side, in MPa; is the secondary side absolute pressure, in MPa, is the specific gravity of the liquid; is the specific gravity of the gas; t is the fluid temperature, in °C; The above formulas (1) to (7) are combined with the operating parameters to calculate the total refrigerant flow, the liquid circuit refrigerant flow and the gas circuit refrigerant flow, and at the same time calculate the condenser capacity, the oil cooler capacity and the CV value of each regulating valve under the corresponding operating conditions.

[0012] The present invention has the following beneficial effects: The present invention provides a mixer and a pressure regulating plate inside the mixer, and drives a driving gear to rotate through a stepping motor. Since the driving gear meshes with two racks up and down, the upper and lower racks move toward or oppositely during the rotation of the gears. In an initial state, all the pressure regulating plates are parallel to the horizontal plane. When the two racks move toward each other, they respectively drive several movable gears and connecting gears meshed therewith to rotate. Since some pressure regulating plates are connected to the movable gears, the pressure regulating plates connected to the movable gears directly drive the movable gears to rotate when the movable gears rotate, and the connecting gears are connected to the passive gears, and the passive gears are connected to a pressure regulating plate. The connecting gear drives the passive gears to rotate, and at the same time drives the pressure regulating plates to rotate. Therefore, the pressure regulating plates connected to the movable gears and the pressure regulating plates connected to the passive gears rotate in opposite directions. Finally, the pressure regulating plates form a tree-like structure. When liquid and gas enter the interior of the mixing box from an inlet at one end, the tree-like pressure regulating plate combination structure has an effect on the mixing box. The gas-liquid mixture is blocked to a certain extent, thereby slowing down the speed and time of the gas-liquid mixture flowing out from the outlet at the other end. When the opening angle of the pressure regulating plate combination with a tree-branch structure is larger, the resistance to the gas-liquid mixture is greater. After being blocked by the pressure regulating plate, the gas-liquid mixture stays longer in the mixing box and the degree of mixing is higher. When the expansion angle of the pressure regulating plate combination with a tree-branch structure is about small, or not expanded, the gas and liquid entering the mixing box from the inlet end have no structure to block them, so they can flow out of the outlet in a straight line at the fastest speed. Therefore, the degree of mixing of the gas-liquid mixture discharged from the outlet is worse at this time. This structure can adjust the mixing degree of the gas-liquid mixture to adapt to the test of the compressor under different working conditions. A small number of compressor tests need to be started with liquid. At this time, the mixing degree of the gas-liquid mixture needs to be reduced to complete the test. Therefore, this structure can expand the operating range of the compressor performance test and meet the compressor performance test under different working conditions.

[0013] The present invention sets a refrigerant component. When the high-temperature and high-pressure gaseous refrigerant is discharged from the outlet of the tested compressor, a part of the high-temperature and high-pressure refrigerant is directly poured into the mixing box through a tee, and the other part of the high-temperature and high-pressure refrigerant is condensed by a condenser to become liquid low-temperature and high-pressure refrigerant which enters the mixing box. The liquid refrigerant and the gaseous refrigerant are mixed. The mixing ratio can be adjusted by two regulating valves respectively, so as to meet the requirements of the test conditions, and the temperature and pressure of the refrigerant of the tested compressor are adjusted accordingly, thereby reducing the cost of the test equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0015] Figure 1 This is the principle diagram of the calorimetric performance test of the second refrigerant of the compressor; Figure 2 A diagram of the test equipment for the device for testing the performance of a compressor with rapid and stable working conditions provided by the present invention; Figure 3 Schematic diagram of the internal cross-sectional structure of the mixer in the present invention; Figure 4 For the present invention Figure 3 Enlarged view of point A in the middle; Figure 5 This is a test logic diagram of the test system of the present invention.

[0016] In the accompanying drawings, the components represented by the reference numerals are listed as follows: 1. Oil separator; 2. Oil flow meter; 3. Gas line total flow meter; 4. Oil cooler; 5. Return oil flow regulating valve; 6. Exhaust pressure regulating valve; 7. Condenser; 8. Mixer; 81. Mixing chamber; 82. Stepper motor; 83. Driving gear; 84. Rack; 85. Movable gear; 86. Pressure regulating plate; 87. Connecting gear; 88. Passive gear; 9. Liquid line flow meter; 10. Suction pressure regulating valve; 11. Compressor under test; 12. Suction temperature regulating valve. DETAILED DESCRIPTION

[0017] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0018] See also Figure 1-5, the present invention is a compressor performance test device with fast and stable working conditions, including a test device and a test system with a communication control connection therewith, the test device including an oil separation component and a refrigerant component; The oil separation component includes an oil separator 1, which is connected to an oil flow meter 2 and a gas line total flow meter 3 through a tee, and the other end of the oil flow meter 2 is connected in series with an oil cooler 4 through an oil line pipeline. A return oil flow regulating valve 5 is connected in series to the oil line pipeline between the oil flow meter 2 and the oil cooler 4. The refrigerant component includes an exhaust pressure regulating valve 6, one end of the exhaust pressure regulating valve 6 is connected to the gas circuit total flow meter 3, and the other end is connected to the condenser 7 through a refrigerant pipe. The condenser 7 is connected in series with the mixer 8 through the refrigerant pipe, and a liquid circuit flow meter 9 and an intake temperature regulating valve 12 are installed on the refrigerant pipe between the condenser 7 and the mixer 8; a refrigerant pipe extends outward from the refrigerant pipe between the exhaust pressure regulating valve 6 and the condenser 7, and the refrigerant pipe is connected to the mixer 8, and an intake pressure regulating valve 10 is installed on the refrigerant pipe; the outlet of the mixer 8 and the outlet of the oil cooler 4 are both connected to the air inlet of the tested compressor 11, and the air outlet of the tested compressor 11 is connected in series with the oil separator 1.

[0019] Among them, the mixer 8 includes a mixing chamber 81, and a liquid inlet interface and a liquid outlet interface are respectively provided at the front and rear ends of the mixing chamber 81, and a stepper motor 82 is installed on the outer wall of one side of the mixing chamber 81. The output end of the stepper motor 82 passes through the mixing chamber 81 to the inside thereof, and is fixedly connected to one side of a driving gear 83. The upper and lower sides of the driving gear 83 are respectively meshed with racks 84, and the rack 84 is slidably installed on the inner wall of the mixing chamber 81. The tooth grooves of the two racks 84 are respectively meshed with two movable gears 85 and a connecting gear 87, and the connecting gear 87 is staggeredly meshed with a driven gear 88. A pressure regulating plate 86 is fixedly installed on one end of the driven gear 88 and one end of the movable gear 85. The pressure regulating plate 86 installed on one end of the passive gear 88 and the pressure regulating plate 86 installed on one end of the movable gear 85 are staggered, and the maximum adjustment angle of each pressure regulating plate 86 does not exceed 30°.

[0020] The test system includes a main control module, a refrigerant circulation module of the tested machine and an oil treatment module which establish communication connection with the main control module; Main control module: used to control the relevant mechanisms of the test equipment according to the instructions of other modules of the test system, and receive the output data of the relevant mechanisms of the test equipment; Refrigerant circulation module of the tested machine: used to control the relevant mechanisms of the refrigerant components in the test equipment, mix the high-temperature and high-pressure gaseous refrigerant at the exhaust end with the supercooled liquid refrigerant according to the test requirement ratio and return it to the suction end of the tested compressor 11, so as to change the control working conditions of the tested compressor; wherein the control working conditions of the tested compressor include suction temperature, suction pressure and exhaust pressure; Oil processing module: used to control the oil separation component to separate the lubricating oil contained in the refrigerant during the test operation of the tested compressor 11, while maintaining the oil temperature of the lubricating oil; Measurement and control module: used to calculate the opening of each regulating valve and the auxiliary working condition preset through the parameters of the tested compressor 11 and the control working condition parameters. When the tested compressor 11 is turned on, each actuator of the test equipment is adjusted according to the preset output to quickly reach the control working condition; Calculation module: used to calculate the compressor capacity, the theoretical mass flow of the radial compressor under the test conditions and the flow capacity of the regulating valve through the compressor capacity calculation formula combined with the data of the test equipment; the calculated liquid flow value is compared with the test value of the liquid flow meter 9 to verify the accuracy of the test result.

[0021] In the present invention, by presetting compressor parameters such as compressor speed, displacement, volumetric efficiency, etc., plus the working conditions to be controlled such as suction temperature, suction pressure, exhaust pressure, valve pre-temperature, etc., and the CV value corresponding relationship table provided by the regulating valve supplier, the theoretical opening of each regulating valve under the corresponding conditions can be calculated according to Formula 6 and Formula 7. When the equipment is started, the early intervention control is carried out by pre-sending the regulating valve opening to achieve rapid and stable working conditions. With the high-efficiency oil separation system, the refrigerant mass flow can be accurately controlled and the compressor performance can be accurately measured.

[0022] Control of key compressor parameters by regulating valves: The control conditions that affect compressor performance on the refrigerant side include: suction temperature, suction pressure, and exhaust pressure. These three conditions are all controlled by regulating valves in the system. The suction temperature is controlled by the amount of liquid refrigerant after condensation, the suction pressure is controlled by the amount of gas refrigerant after exhaust throttling, the exhaust pressure is controlled by adjusting the opening of the regulating valve at the compressor outlet, and the overall intermediate pressure of the system is controlled by the temperature of the cold water passing through the condenser; Adopt high-efficiency oil separation system: through oil separation heating and high-efficiency oil separator, the oil in the refrigerant is separated as much as possible, while ensuring that as little refrigerant as possible remains in the return oil, ensuring that the mass flow meter measured by the total flow meter of the gas circuit is more accurate, and the calculated compressor performance is more reliable; Regulating valve and auxiliary working condition preset: The regulating valve opening and auxiliary working condition preset are calculated by the compressor parameters and control working condition parameters in conjunction with the software. When the compressor is started, the corresponding regulating valve and other control actuators are pre-adjusted according to the preset output to speed up the working condition control speed; Balance ratio calculation with adiabatic mixer: By insulating the mixer and calibrating the heat leakage coefficient, the liquid mass flow rate can be calculated according to the formula through the enthalpy value of the gas-liquid path at the mixer inlet, the gaseous enthalpy value at the outlet, and the total refrigerant flow. The balance ratio is calculated by combining the calculated liquid mass flow rate with the mass flow rate measured by the flowmeter to ensure the reliability of the test results.

[0023] like Figure 2 The figure shows the rapid performance test flow path of the tested compressor. At this time, the pneumatic valves of the test path are: VG1 and VG3 are open, and VG2 is closed. OS is an oil treatment device. FM1 measures the total refrigerant mass flow rate discharged from the compressor, which is used to calculate the compressor performance. The compressor exhaust pressure P2 is controlled by the regulating valve VC1, the compressor suction pressure P1 is controlled by the gas circuit regulating valve VC2, the compressor suction temperature T1 is controlled by the liquid circuit regulating valve VC3, the return oil flow FM3 is controlled by the regulating valve VC4, and the return oil temperature T7 is controlled by the oil cooler OC. The mixer MIX outlet temperature T5 and outlet pressure P5 are used to measure the mixer outlet enthalpy value. , with the total gas circuit refrigerant mass flow FM1, as well as the gas circuit valve front temperature T3, gas circuit valve front pressure P3 to obtain the enthalpy value The enthalpy value is obtained by the temperature T4 before the liquid valve and the pressure P4 before the gas and liquid valve. , by comparing the calculated liquid flow rate with the test value of the liquid flow meter FM3, the reliability of the test results is verified.

[0024] The test system further includes a constant temperature water control module: the water inlet temperature of the condenser is quickly controlled during the refrigerant circulation process by means of a water pump, a three-way valve and an electric heater arranged outside the condenser, thereby quickly controlling the shutdown balance pressure of the start-stop condition; when the constant temperature water control module is operating normally, it exchanges heat for the condenser to ensure that the refrigerant has a subcooling degree before entering the suction temperature regulating valve (12).

[0025] The test system further comprises an electrical control unit, which is used for human-machine interaction and automatic experiments and is composed of a computer unit, a programmable controller, a touch screen and a digital control instrument. The computer unit is used for automatically setting and sending test conditions, calculating the initial opening of each regulating valve according to the working conditions, and monitoring the entire experimental process. At the same time, it collects all data of the test equipment, judges the stability of the working conditions and data, calculates, and outputs complete test data and a test report; when the test working conditions are stable, it records the output values ​​of each regulating instrument, calculates the deviation between the theoretical calculated value and the actual value, and uses it for subsequent tests of the same working conditions; the programmable controller is used for programming the control logic and alarm action of the test equipment for automatic control; the touch screen is a human-machine interaction interface, and the opening and closing of the test equipment and the alarm prompt are all realized through the touch screen; the digital control instrument controls the suction and exhaust pressure, suction temperature, return oil temperature, return oil flow, ambient temperature and cold water temperature parameters of each circuit of the tested compressor (11) by negative feedback.

[0026] Among them, the calculation formulas for the compressor capacity, the theoretical mass flow rate of the radial compressor under the test conditions, and the flow capacity of the regulating valve in the calculation module include the following: The compressor capacity calculation formula includes the refrigerant liquid circuit flow calculation formula, the cooling capacity calculation formula and the heating capacity calculation formula; The formula for calculating the flow rate of the refrigerant liquid circuit is shown in formula (1): (1); The cooling capacity calculation formula is shown in formula (2): (2); The calculation formula of heating capacity is shown in formula (3): (3); in: Heat leakage for mixer; is the theoretical specific enthalpy of the refrigerant entering the tested compressor under basic test conditions; is the specific enthalpy of the evaporated refrigerant leaving the calorimeter; is the measured specific enthalpy of the refrigerant leaving the compressor under test under basic test conditions; The theoretical specific enthalpy of the refrigerant before the evaporator expansion valve in the refrigeration cycle where the tested compressor is located under basic test conditions; is the specific enthalpy of the refrigerant liquid entering the main circuit refrigerant liquid inlet expansion valve; It is the measured specific volume of the refrigerant vapor entering the tested compressor under basic test conditions; is the theoretical specific volume of the refrigerant vapor entering the tested compressor under basic test conditions; The theoretical mass flow rate calculation formula flowing through the tested compressor under known test compressor speed, displacement, volumetric efficiency and test conditions is shown in formula (4): (4); in: is the solvent efficiency of the tested compressor, in units of %; n is the speed of the tested compressor, in units of r / min; is the theoretical displacement of the tested compressor, in units of , v is the suction volume of the tested compressor, in units of ; The calculation formulas for the flow capacity of the regulating valve are shown in equations (5), (6) and (7): (5); (6); (7); in: It is the flow capacity of the suction temperature control valve under the test conditions; It is the flow capacity of the suction pressure regulating valve under the test conditions; is the liquid flow rate in units of , is the gas flow rate, in units of ; is the absolute pressure on the primary side, in MPa; is the secondary side absolute pressure, in MPa, is the specific gravity of the liquid; is the specific gravity of the gas; t is the fluid temperature, in °C; Formula (1) to Formula (7) are combined with the operating parameters to calculate the total refrigerant flow, liquid circuit refrigerant flow, and gas circuit refrigerant flow. At the same time, the condenser capacity, oil cooler capacity, and CV values ​​of each regulating valve corresponding to the operating condition are calculated.

[0027] In the present invention, the following parameters need to be controlled or tested during the compressor performance test: Inspiratory pressure : Refers to the gas pressure at the suction port of the compressor in the test equipment; Exhaust pressure : Refers to the final gas pressure discharged from the compressor; Pressure before liquid valve : refers to the pressure before the expansion valve of the liquid circuit in the refrigeration cycle where the compressor is located; Pressure after gas line valve : Refers to the pressure after the expansion valve of the gas circuit in the refrigeration cycle where the compressor is located; Mixer outlet pressure : refers to the refrigerant pressure at the outlet of the gas-liquid mixer; Suction temperature : refers to the refrigerant temperature at the compressor suction port; Exhaust temperature : refers to the temperature of the gas discharged after the compressor works; Temperature before liquid valve : Refers to the temperature before the expansion valve of the liquid circuit in the refrigeration cycle where the compressor is located; Temperature after gas line valve : refers to the temperature after the expansion valve of the gas circuit in the refrigeration cycle where the compressor is located; Mixer outlet temperature : refers to the refrigerant temperature at the outlet of the gas-liquid mixer; Mixer heat leakage : refers to the heat exchange between the mixer and its surrounding environment temperature; Total refrigerant flow rate in gas circuit : The refrigerant mass flow rate measured by the total gas flow meter in the refrigerant circulation system; Liquid circuit refrigerant flow : The refrigerant mass flow rate measured by the liquid flow meter in the refrigerant circulation system; Oil return flow : The oil flow rate that returns to the suction end of the compressor after being processed by the oil separator; Theoretical specific enthalpy before valve : The theoretical specific enthalpy of the refrigerant before expansion of the evaporator in the refrigeration cycle where the compressor is located under the prescribed basic test conditions; Measured specific enthalpy before the liquid valve : The actual specific enthalpy of the refrigerant before the expansion of the liquid circuit in the refrigeration cycle where the compressor is located under the prescribed basic test conditions; Measured specific enthalpy before the gas circuit valve : The actual specific enthalpy of the refrigerant after gas expansion in the refrigeration cycle where the compressor is located under the prescribed basic test conditions; Measured mixer outlet enthalpy : The actual specific enthalpy of the refrigerant at the mixer outlet in the refrigeration cycle where the compressor is located under the prescribed basic test conditions; Condenser (CON): By controlling the water tank temperature, the water inlet temperature of the condenser is controlled to maintain a stable system intermediate pressure. The initial suction and exhaust pressure and the opening of the temperature regulating valve can be calculated according to the actual control conditions. Oil cooler (OC): controls the compressor return oil temperature through the fixed cooling capacity in the coil and the electric heating output. The initial output oil temperature can be controlled according to the working conditions; Mixer (MIX): The liquid refrigerant and the gas refrigerant are fully mixed again. It is also the key to calculate the liquid flow rate. The corresponding liquid flow rate can be calculated through the mixer gas inlet enthalpy value, liquid inlet enthalpy value, total refrigerant flow rate, mixer outlet enthalpy value and heat leakage. The changed liquid flow rate can be used for comparison with the result measured by the liquid flow meter; Exhaust pressure regulating valve (VC1): The compressor exhaust pressure is regulated by adjusting the opening of the valve. The opening of the valve can be preset based on the actual test conditions, compressor speed and control parameters combined with the CV value corresponding output relationship provided by the regulating valve manufacturer, so that the preset opening can be set when starting up, allowing the working conditions to be reached faster; Suction pressure regulating valve (VC2): The suction pressure of the compressor is controlled by adjusting the opening of the gas circuit regulating valve. The opening of the valve can be preset based on the actual test conditions, compressor speed and control parameters combined with the CV value corresponding output relationship provided by the regulating valve manufacturer, so that the preset opening setting can be made when starting up, allowing the working conditions to be reached faster; Suction temperature control valve (VC3): The suction temperature of the compressor is controlled by adjusting the opening of the liquid circuit control valve. The opening of the valve can be preset based on the actual test conditions, compressor speed and control parameters combined with the CV value corresponding output relationship provided by the control valve manufacturer, so that the preset opening setting can be made when starting up, allowing the working conditions to be reached faster; Oil return flow control valve (VC4): The compressor suction temperature is controlled by adjusting the opening of the liquid circuit control valve. The opening of the valve can be preset based on the actual test conditions, compressor speed and control parameters combined with the CV value corresponding output relationship provided by the control valve manufacturer, so that the preset opening setting can be made when starting up, allowing the working conditions to be reached faster; Mass flow meter (FM1, FM2, FM3): The total gas flow meter FM1 is used to test the total refrigerant mass flow rate discharged from the compressor, which is used to calculate the performance parameters of the compressor such as the cooling capacity and heating capacity; the liquid flow meter FM2 is used to measure the liquid refrigerant mass flow rate, which can be compared with the calculated refrigerant flow rate of the mixer to obtain the balance ratio; the oil flow meter FM3 is used to measure the return oil flow rate and is used in conjunction with the oil return rate control. The return oil flow rate that needs to be controlled is calculated through the total gas flow rate and the oil content that needs to be controlled, and is controlled in conjunction with the regulating valve; Oil Separator (OS): Separate the oil from the refrigerant at the compressor exhaust end for separate oil return control to ensure the accuracy of the actual refrigerant flow test.

[0028] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A compressor performance test device with rapid and stable working conditions, characterized in that: It includes a test device and a test system connected to the test device for communication and control, wherein the test device includes an oil separation component and a refrigerant component; The oil separation component comprises an oil separator (1), the oil separator (1) being connected to an oil flow meter (2) and a gas path total flow meter (3) respectively through a tee, the other end of the oil flow meter (2) being connected in series with an oil cooler (4) through an oil path pipeline, and an oil return flow regulating valve (5) being connected in series to the oil path pipeline between the oil flow meter (2) and the oil cooler (4); The refrigerant assembly comprises an exhaust pressure regulating valve (6), one end of the exhaust pressure regulating valve (6) is connected to a gas circuit total flow meter (3), and the other end thereof is connected to a condenser (7) via a refrigerant pipeline, the condenser (7) is connected in series with a mixer (8) via the refrigerant pipeline, and a liquid circuit flow meter (9) and an intake temperature regulating valve (12) are installed on the refrigerant pipeline between the condenser (7) and the mixer (8); a refrigerant pipeline extends outward from the refrigerant pipeline between the exhaust pressure regulating valve (6) and the condenser (7), and the refrigerant pipeline is connected to the mixer (8), and an intake pressure regulating valve (10) is installed on the refrigerant pipeline; the outlet of the mixer (8) and the outlet of the oil cooler (4) are both connected to the air inlet of the tested compressor (11), and the air outlet of the tested compressor (11) is connected in series with the oil separator (1).

2. A compressor performance test device with rapid and stable working conditions according to claim 1, characterized in that: The mixer (8) comprises a mixing chamber (81), wherein the mixing chamber (81) is provided with a liquid inlet interface and a liquid outlet interface at both ends thereof, and a stepping motor (82) is installed on one side of the outer wall of the mixing chamber (81), wherein the output end of the stepping motor (82) passes through the mixing chamber (81) to the inside thereof and is fixedly connected to one side of a driving gear (83), wherein the driving gear (83) is meshedly connected with racks (84) at the upper and lower sides thereof, and wherein the racks (84) are slidably installed on the inner wall of the mixing chamber (81), and the two racks (84) are arranged to move the mixing chamber (81) and the mixing chamber (81) ... Two movable gears (85) and a connecting gear (87) are respectively meshed on the tooth grooves of the rack (84); the connecting gear (87) is staggeredly meshed with a driven gear (88); one end of the driven gear (88) and one end of the movable gear (85) are both fixedly mounted with a pressure regulating plate (86); the pressure regulating plate (86) mounted on one end of the driven gear (88) and the pressure regulating plate (86) mounted on one end of the movable gear (85) are staggered, and the maximum adjustment angle of each of the pressure regulating plates (86) does not exceed 30°.

3. A compressor performance test device with rapid and stable working conditions according to claim 2, characterized in that: The test system includes a main control module, and a refrigerant circulation module and an oil treatment module of the machine under test that establish communication connection with the main control module; Main control module: used to control the relevant mechanisms of the test equipment according to the instructions of other modules of the test system, and receive the output data of the relevant mechanisms of the test equipment; The refrigerant circulation module of the tested machine is used to control the relevant mechanism of the refrigerant component in the test equipment, mix the high-temperature and high-pressure gaseous refrigerant at the exhaust end with the supercooled liquid refrigerant according to the test requirement ratio and return it to the suction end of the tested compressor (11), thereby changing the control working condition of the tested compressor; wherein the control working condition of the tested compressor includes the suction temperature, suction pressure and exhaust pressure; Oil processing module: used for controlling the oil separation component to separate the lubricating oil contained in the refrigerant during the test operation of the tested compressor (11), while maintaining the temperature of the lubricating oil; The measurement and control module is used to calculate the opening of each regulating valve and the auxiliary working condition preset by correcting the parameters of the tested compressor (11) and the control working condition parameters, and when the tested compressor (11) is turned on, each actuator of the test equipment is adjusted according to the preset output amount to quickly reach the control working condition; Calculation module: used to calculate the compressor capacity, the theoretical mass flow of the radial compressor under the test conditions and the flow capacity of the regulating valve by combining the compressor capacity calculation formula with the data of the test equipment; the calculated liquid flow value is compared with the test value of the liquid flow meter (9) to verify the accuracy of the test result.

4. A compressor performance test device for rapid and stable working conditions according to claim 3, characterized in that: The test system also includes a constant temperature water control module: a water pump, a three-way valve and an electric heater arranged outside the condenser are used to quickly control the condenser water inlet temperature during the refrigerant circulation process, thereby quickly controlling the shutdown condition balance pressure of the start-stop condition; when the constant temperature water control module is operating normally, it exchanges heat for the condenser to ensure that the refrigerant has a subcooling degree before entering the suction temperature regulating valve (12).

5. A compressor performance test device with rapid and stable working conditions according to claim 4, characterized in that: The test system further comprises an electrical control unit, which is used for human-machine interaction and automatic experiments and is composed of a computer unit, a programmable controller, a touch screen and a digital control instrument. The computer unit is used for automatically setting and sending test conditions, calculating the initial opening of each regulating valve according to the working conditions, and monitoring the entire experimental process. At the same time, it collects all data of the test equipment, judges the stability of the working conditions and data, calculates, and outputs complete test data and a test report; when the test working conditions are stable, it records the output values ​​of each regulating instrument, calculates the deviation between the theoretical calculated value and the actual value, and uses it for subsequent tests of the same working conditions; the programmable controller is used for programming the control logic and alarm action of the test equipment and performing automatic control; the touch screen is a human-machine interaction interface, and the opening and closing of the test equipment and the alarm prompt are all realized through the touch screen; the digital control instrument controls the suction and exhaust pressure, suction temperature, return oil temperature, return oil flow, ambient temperature and cold water temperature parameters of each circuit of the tested compressor (11) by negative feedback.

6. A compressor performance test device with rapid and stable working conditions according to claim 5, characterized in that: The calculation formulas in the calculation module for the compressor capacity, the theoretical mass flow of the radial compressor under the test conditions, and the flow capacity of the regulating valve include the following: The compressor capacity calculation formula includes a refrigerant liquid circuit flow calculation formula, a cooling capacity calculation formula, and a heating capacity calculation formula; The refrigerant liquid circuit flow calculation formula is shown in formula (1): （1）； The cooling capacity calculation formula is shown in formula (2): （2）； The heating capacity calculation formula is shown in formula (3): （3）； in: Heat leakage for mixer; is the theoretical specific enthalpy of the refrigerant entering the tested compressor under basic test conditions; is the specific enthalpy of the evaporated refrigerant leaving the calorimeter; is the measured specific enthalpy of the refrigerant leaving the compressor under test under basic test conditions; The theoretical specific enthalpy of the refrigerant before the evaporator expansion valve in the refrigeration cycle where the tested compressor is located under basic test conditions; is the specific enthalpy of the refrigerant liquid entering the main circuit refrigerant liquid inlet expansion valve; It is the measured specific volume of the refrigerant vapor entering the tested compressor under basic test conditions; is the theoretical specific volume of the refrigerant vapor entering the tested compressor under basic test conditions; The theoretical mass flow rate calculation formula flowing through the tested compressor under known test compressor speed, displacement, volumetric efficiency and test conditions is shown in formula (4): （4）； in: is the solvent efficiency of the tested compressor, in units of %; n is the speed of the tested compressor, in units of r / min; is the theoretical displacement of the tested compressor, in units of , v is the suction volume of the tested compressor, in units of ; The calculation formulas for the flow capacity of the regulating valve are shown in equations (5), (6) and (7): （5）； （6）； （7）； in: It is the flow capacity of the suction temperature control valve under the test conditions; It is the flow capacity of the suction pressure regulating valve under the test conditions; is the liquid flow rate in units of , is the gas flow rate, in units of ; is the absolute pressure on the primary side, in MPa; is the secondary side absolute pressure, in MPa, is the specific gravity of the liquid; is the specific gravity of the gas; t is the fluid temperature, in °C; The above formulas (1) to (7) are combined with the operating parameters to calculate the total refrigerant flow, the liquid circuit refrigerant flow and the gas circuit refrigerant flow, and at the same time calculate the condenser capacity, the oil cooler capacity and the CV value of each regulating valve under the corresponding operating conditions.

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