Catalyst performance test bench and method, upper computer, vehicle and storage medium

Abstract

The invention relates to the technical field of testing, in particular to a catalytic converter performance testing rack and method, an upper computer, a vehicle and a storage medium. The catalyst is arranged on an exhaust pipe of the engine; the data acquisition assembly is used for acquiring related data of the engine and the catalytic converter; and the upper computer is used for generating a target test process according to the target performance test requirement of the catalyst, controlling the engine and the catalyst to operate according to the target test process, and generating a performance test result of the catalyst according to the related data of the engine and the catalyst after the test is finished. Therefore, the problem that the test result of the performance of the catalyst is not accurate in the prior art is solved.

Description

Technical Field

[0001] The present application relates to the field of testing technology, and in particular to a catalyst performance test bench, method, host computer, vehicle and storage medium. Background Art

[0002] A three-way catalytic converter is a device installed in the exhaust system of a car to reduce harmful gases emitted by the engine. The main harmful gases treated include carbon monoxide, unburned hydrocarbons and nitrogen oxides. The catalyst converts these harmful gases into more harmless substances such as carbon dioxide, water and nitrogen by using precious metals (such as platinum, palladium, rhodium) as catalysts.

[0003] The performance of the catalyst directly affects the emission level and environmental performance of the car. With the continuous improvement of environmental protection requirements, the evaluation of catalyst performance has become particularly important. At present, the SRC exhaust temperature of hybrid models is generally lower than that of traditional fuel vehicles. The previously commonly used four-condition 875 aging may no longer be completely suitable for the rapid aging of the catalyst bench of hybrid vehicles. In actual vehicle applications, the degradation of the catalyst is monitored in real time through the degradation of the oxygen storage capacity of the catalyst. The traditional bench oxygen storage capacity only considers the change of "oxygen storage time" from rich to lean air-fuel ratio, but ignores the change of "oxygen release time" from lean to rich air-fuel ratio, resulting in inaccurate test results. Summary of the invention

[0004] The present application provides a catalyst performance test bench, method, host computer, vehicle and storage medium to solve the problem of inaccurate test results for catalyst performance in related technologies.

[0005] The first aspect of the present application provides a catalyst performance test bench, comprising the following steps: an engine; a catalyst arranged on the exhaust pipe of the engine; a data acquisition component for collecting relevant data of the engine and the catalyst; a host computer for generating a target test process according to the target performance test requirements of the catalyst, controlling the engine and the catalyst to operate according to the target test process, and generating a performance test result of the catalyst according to the relevant data of the engine and the catalyst after the test.

[0006] Optionally, the data acquisition component includes at least one of a first temperature sensor, a second temperature sensor, a third temperature sensor, a front oxygen sensor, a rear oxygen sensor, a wide-range oxygen sensor, an exhaust flow meter, and an intake flow meter.

[0007] Optionally, the target performance test requirement includes an aging performance test requirement and an oxygen storage performance test requirement, wherein, if the target performance test requirement is an aging performance test requirement, the data acquisition component includes a first temperature sensor, a second temperature sensor, a third temperature sensor, a front oxygen sensor, a rear oxygen sensor, a wide-range oxygen sensor and an exhaust flow meter, and the relevant data include at least one of the bed temperature of the catalyst, the inlet and outlet temperatures of the catalyst, the inlet and outlet oxygen concentrations of the catalyst, the excess air coefficient of the engine, and the gas flow rate exhausted by the catalyst; if the target performance test requirement is an oxygen storage performance test requirement, the data acquisition component includes a front oxygen sensor, a rear oxygen sensor, a wide-range oxygen sensor and an intake flow meter, and the relevant data include at least one of the intake flow rate of the engine, the excess air coefficient of the engine, and the inlet and outlet oxygen concentrations of the catalyst.

[0008] Optionally, it also includes: a secondary air supply system arranged at the air inlet of the catalyst, which is used to supply air to the catalyst to adjust the oxygen concentration of the exhaust gas in the air inlet of the catalyst.

[0009] Optionally, if the target performance test requirement is an oxygen storage performance test requirement, the host computer is further used to: obtain the voltage generated by the front oxygen sensor and the rear oxygen sensor based on the oxygen concentration; respectively determine the mutation moments when the voltages of the front oxygen sensor and the rear oxygen sensor change from a first threshold to a second threshold; calculate the oxygen storage capacity and oxygen release capacity of the catalyst based on the engine's excess air coefficient, the engine's intake flow, the mutation moment of the voltage of the front oxygen sensor, and the mutation moment of the voltage of the rear oxygen sensor; and generate a performance test result of the catalyst based on the oxygen storage capacity and / or oxygen release capacity.

[0010] Optionally, the target test process is: obtain a target test phase of the catalyst, wherein the target test phase includes the first to fifth phases; obtain test data corresponding to each test phase; generate a target test instruction based on the target test phase and the corresponding test data; control the engine and the catalyst to perform tests of the first to fifth phases in sequence according to the target test instruction.

[0011] A second aspect of the present application provides a catalyst performance testing method, which is tested using a catalyst performance test bench such as the above embodiment, and includes the following steps: generating a target test process based on the target performance test requirements of the catalyst; controlling the engine and catalyst to run the test according to the target test process; after the test, generating a performance test result of the catalyst based on relevant data of the engine and catalyst.

[0012] The third aspect of the present application provides a host computer, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor executes the program to perform the catalyst performance testing method as described in the above embodiment.

[0013] A fourth aspect of the present application provides a vehicle, comprising a catalyst tested using the catalyst performance testing method of the above embodiment.

[0014] The fifth aspect of the present application provides a computer-readable storage medium having a computer program or instructions stored thereon, and the computer program or instructions are executed by a processor to perform a catalyst performance testing method as described above.

[0015] Therefore, this application has at least the following beneficial effects:

[0016] The embodiment of the present application integrates the engine, catalyst, data acquisition component and host computer to form a complete test bench. The host computer can generate a target test process according to the target performance test requirements of the catalyst and control the entire test process, thereby improving the automation of the test and reducing human intervention. The performance test results can be generated based on the relevant data collected by the data acquisition component, ensuring the accuracy and reliability of the test results, and the corresponding test process can be generated according to the target performance test requirements, which is applicable to a variety of test scenarios. Therefore, the technical problems such as inaccurate test results for catalyst performance in the related technology are solved.

[0017] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0019] Figure 1 A schematic diagram of a catalyst performance test bench provided according to an embodiment of the present application;

[0020] Figure 2 A schematic diagram of a catalyst aging performance test bench provided according to an embodiment of the present application;

[0021] Figure 3 A schematic diagram of changes in the air-fuel ratio of an engine during an aging cycle according to an embodiment of the present application;

[0022] Figure 4 A schematic diagram of changes in the air-fuel ratio at the catalyst inlet during an aging cycle according to an embodiment of the present application;

[0023] Figure 5 A schematic diagram of a catalyst oxygen storage performance test bench provided according to an embodiment of the present application;

[0024] Figure 6A schematic diagram of a sensor installed around a catalyst according to an embodiment of the present application;

[0025] Figure 7 A schematic diagram of data from a catalyst oxygen storage capacity test bench test provided according to an embodiment of the present application;

[0026] Figure 8 A schematic diagram of data of an oxygen release test of a catalyst oxygen storage test bench provided according to an embodiment of the present application;

[0027] Fig. 9 A flow chart of a catalyst performance testing method provided according to an embodiment of the present application;

[0028] Fig.10 It is a schematic diagram of the structure of a host computer provided according to an embodiment of the present application. DETAILED DESCRIPTION

[0029] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0030] Before describing the solution of the present application, the specific usage of the current catalyst is introduced.

[0031] When the oil-electric hybrid vehicle is working at a higher working condition, the electric motor assists the engine to output power together. Therefore, compared with traditional vehicles, the maximum working condition of the hybrid vehicle engine is lower and the exhaust temperature is relatively lower. In addition, the cold start process is optimized with the assistance of the electric motor. In a low temperature environment, the electric motor can quickly provide power to help the engine reach the normal working temperature faster, reduce the time of the cold start phase, and thus reduce exhaust emissions. Therefore, compared with traditional fuel vehicles, which have higher exhaust emissions during the cold start phase and need to increase the content of precious metals, the precious metal content of the catalyst used in hybrid vehicles can be relatively reduced. As for the four-condition 875 bench aging of the 200,000-kilometer equivalent aging of traditional fuel vehicles, in the actual operation of hybrid vehicles, there is no need to consider the impact of higher temperatures on the degradation of their catalysts. The aging temperature can be appropriately lowered and a suitable durability cycle can be adopted.

[0032] The SRC exhaust temperature of hybrid vehicles is generally lower than that of traditional fuel vehicles. The previously commonly used four-condition 875 aging may no longer be completely suitable for the rapid aging of the catalyst bench of hybrid vehicles. The choice of which aging cycle to use is an issue that needs to be considered for different hybrid models and different calibration strategies.

[0033] In addition, as the precious metal content of the catalyst gradually decreases, the corresponding amount of catalyst coating is also reduced. However, in actual vehicle applications, it is necessary to monitor the OBD (On Board Diagnostics) alarm in real time, that is, to monitor the degradation of the catalyst in real time through the degradation of the oxygen storage capacity of the catalyst. The traditional bench oxygen storage capacity OSC only considers the change of "oxygen storage time" from rich to lean air-fuel ratio, but ignores the change of "oxygen release time" from lean to rich air-fuel ratio. Therefore, it is of great practical significance to adopt a more scientific and reasonable evaluation method of oxygen storage and oxygen release to effectively monitor the post-treatment of hybrid vehicles.

[0034] To this end, the present application provides a catalyst performance test bench, which integrates an engine, a catalyst, a data acquisition component and a host computer to form a complete test bench. The host computer can generate a target test process according to the target performance test requirements of the catalyst and control the entire test process, thereby improving the degree of automation of the test and reducing human intervention. It can also generate performance test results based on relevant data collected by the data acquisition component, ensuring the accuracy and reliability of the test results, and can generate corresponding test processes according to different target performance test requirements, which is suitable for a variety of test scenarios.

[0035] Specifically, Figure 1 A schematic diagram of a catalyst performance test bench provided in an embodiment of the present application.

[0036] like Figure 1 As shown, the catalyst performance test bench 10 includes: an engine 11, a catalyst 12, a data acquisition component 13 and a host computer 14.

[0037] Among them, the catalyst 12 is arranged on the exhaust pipe of the engine 11; the data acquisition component 13 is used to collect relevant data of the engine and the catalyst; the upper computer 14 generates a target test process according to the target performance test requirements of the catalyst, controls the engine 11 and the catalyst 12 to run according to the target test process, and after the test is completed, generates a performance test result of the catalyst 12 according to the relevant data of the engine 11 and the catalyst 12.

[0038] It can be understood that the embodiment of the present application has built a catalyst performance test bench, which integrates the engine 11, the catalyst 12, the data acquisition component 13 and the host computer 14 to form a complete test system. The host computer 14 can generate a target test process according to the target performance test requirements of the catalyst and control the entire test process, thereby improving the degree of automation of the test and reducing human intervention. It can also generate performance test results based on the relevant data collected by the data acquisition component 13, thereby ensuring the accuracy and reliability of the test results, and can generate corresponding test processes according to the target performance test requirements, which is suitable for a variety of test scenarios.

[0039] In an embodiment of the present application, a performance test result of the catalyst is generated based on relevant data of the engine and the catalyst. For example, the performance of the catalyst can be evaluated based on the oxygen storage and release capacity of the catalyst, the bed temperature of the catalyst, the inlet and outlet temperatures, the oxygen concentrations at the inlet and outlet, the exhaust flow rate, etc. Specifically, the data collected after the test can be compared with the data before the test.

[0040] In the embodiment of the present application, the data acquisition component 13 includes at least one of a first temperature sensor, a second temperature sensor, a third temperature sensor, a front oxygen sensor, a rear oxygen sensor, a wide-range oxygen sensor, an exhaust flow meter and an intake flow meter.

[0041] Among them, the first temperature sensor, the second temperature sensor and the third temperature sensor can be K-type thermocouples; the intake flow meter can be a hot wire intake flow meter, the unit is kg / h, using a hot wire as a sensor, and calculating the intake volume by measuring the speed and density of the intake air flow.

[0042] It should be noted that the settings and functions of various data acquisition components are different. For example, the first temperature sensor is used to measure the bed temperature of the catalyst; the second temperature sensor is arranged at the air inlet of the catalyst, and is used to measure the air inlet temperature of the catalyst; the third temperature sensor is arranged at the air outlet of the catalyst, and is used to measure the air outlet temperature of the catalyst; the front oxygen sensor is arranged in the air intake pipe of the catalyst, and is used to measure the oxygen concentration at the air intake of the catalyst; the rear oxygen sensor is arranged in the exhaust pipe of the catalyst, and is used to measure the oxygen concentration at the air outlet of the catalyst; the wide-range oxygen sensor is used to measure the excess air coefficient of the exhaust gas discharged by the engine; the exhaust flow meter is used to measure the gas flow discharged by the catalyst; the intake flow meter is used to measure the intake flow of the engine.

[0043] In the embodiment of the present application, the target performance test requirements include aging performance test requirements and oxygen storage performance test requirements, wherein:

[0044] If the target performance test requirement is an aging performance test requirement, the data acquisition component 13 includes a first temperature sensor, a second temperature sensor, a third temperature sensor, a front oxygen sensor, a rear oxygen sensor, a wide-range oxygen sensor, and an exhaust flow meter, and the relevant data includes at least one of the bed temperature of the catalyst, the inlet and outlet temperatures of the catalyst, the inlet and outlet oxygen concentrations of the catalyst, the excess air coefficient of the engine, and the gas flow rate discharged from the catalyst;

[0045] If the target performance test requirement is an oxygen storage performance test requirement, the data acquisition component 13 includes a front oxygen sensor, a rear oxygen sensor, a wide-range oxygen sensor and an intake flow meter, and the relevant data includes at least one of the intake flow of the engine and the oxygen concentration of the intake and outlet of the catalyst.

[0046] It is understandable that due to different target performance test requirements, the embodiment of the present application can determine the specific components used by the specific data acquisition component 13 and the relevant data of the engine and catalyst collected by the data acquisition component according to different performance test requirements.

[0047] In the embodiment of the present application, the catalyst performance test bench 10 of the embodiment of the present application further includes: a secondary air supply system.

[0048] The secondary air supply system is disposed at the air inlet of the catalyst, and is used to supply air to the catalyst 12 to adjust the oxygen concentration of the exhaust gas in the air inlet of the catalyst 12 .

[0049] It is understandable that the catalyst performance test bench 10 of the embodiment of the present application is also provided with a secondary air supply system for replenishing a certain amount of air into the inlet position of the catalyst during the aging cycle, which is converted into a certain concentration of oxygen to adjust the oxygen concentration in the gas entering the catalyst.

[0050] In an embodiment of the present application, if the target performance test requirement is an oxygen storage performance test requirement, the host computer is further used to: obtain the voltage generated by the front oxygen sensor and the rear oxygen sensor based on the oxygen concentration; respectively determine the mutation moments when the voltages of the front oxygen sensor and the rear oxygen sensor change from a first threshold to a second threshold; calculate the oxygen storage capacity and oxygen release capacity of the catalyst based on the excess air coefficient, the mutation moment of the front oxygen sensor, and the mutation moment of the rear oxygen sensor; and generate a performance test result of the catalyst based on the oxygen storage capacity and / or oxygen release capacity.

[0051] The first threshold value can be set to 0.1V, the second threshold value can be set to 0.45V, and the voltage changes from 0.1V to 0.45V, which can be recorded as the mutation moment.

[0052] It can be understood that the embodiments of the present application can calculate the oxygen storage and oxygen release amount of the catalyst based on the engine's excess air coefficient, the engine's intake flow, the sudden change moment of the voltage of the front oxygen sensor, and the sudden change moment of the voltage of the rear oxygen sensor, and then generate a performance test result of the catalyst based on the oxygen storage and / or oxygen release amount.

[0053] Among them, the calculation formula of oxygen storage capacity OSC is:

[0054]

[0055] Among them, OSC is the oxygen storage capacity of the catalyst, λ is the excess air coefficient value measured by the wide-range oxygen sensor, which is dimensionless; Q is the intake flow rate of the engine; t1 is the moment when the voltage signal of the front oxygen sensor begins to mutate (the voltage value is 0.45V); t2 is the moment when the voltage signal of the rear oxygen sensor begins to mutate (the voltage value is 0.45V); 0.23 is the mass content of oxygen in the air.

[0056] It should be noted that the calculation formula for oxygen release DORC is the same as that for OSC, but the calculated value is negative and needs to be converted into an absolute value in mg. The working principle of the catalyst for storing / releasing oxygen is that the rare earth element cerium (Ce) in the cerium-zirconium oxygen storage material (CeO2-ZrO2) is a variable valence metal, which realizes the storage / release of oxygen through the mutual conversion between Ce3+ and Ce4+.

[0057] In an embodiment of the present application, the target test process is: obtain a target test phase of the catalyst, wherein the target test phase includes the first to fifth phases; obtain test data corresponding to each test phase; generate a target test instruction based on the target test phase and the corresponding test data; control the engine and the catalyst to perform tests of the first to fifth phases in sequence according to the target test instruction.

[0058] It can be understood that the aging performance test requirements of the catalyst of the embodiment of the present application can be divided into five stages, including the first to fifth stages. The air-fuel ratio of the engine, the intake gas of the catalyst, the operating time of each stage, and the bed temperature of the catalyst are all different in each stage. The target test instructions are generated according to the test data corresponding to each test stage and the target test stage, and then the engine and catalyst are controlled to perform the first to fifth stage tests in sequence according to the target test instructions.

[0059] It should be noted that the aging performance test requirements and the oxygen storage performance test requirements share a test process, and some data are collected during the aging performance test to evaluate the oxygen storage performance.

[0060] Among them, the first to fifth stages are "theoretical air-fuel ratio-fuel cut-enrichment-enrichment + air replenishment-theoretical air-fuel ratio + air replenishment". "Theoretical air-fuel ratio" is the independent working stage of the engine, such as the time is 35S; "fuel cut-off" is the independent working stage of the motor, such as the time is 10S; "enrichment" is the initial stage of the rapid acceleration stage when the engine resumes work, such as the time is 5S; "enrichment + air replenishment" is the late stage of the engine's acceleration stage, such as the time is 10S; "theoretical air-fuel ratio + air replenishment" is the engine's braking deceleration stage.

[0061] Specifically, the embodiment of the present application builds a catalyst performance test bench. According to the synergy between the motor and the engine, an engine and catalyst consistent with the original vehicle are installed on the engine bench to perform a performance test on the catalyst. Specifically, the test can be divided into an aging performance test and an oxygen storage performance test. The catalyst performance test bench of the present application will be described from two test perspectives below.

[0062] 1. Catalyst aging performance test, test bench construction Figure 2 shown.

[0063] The "fuel-cut" aging cycle is adopted, and the cycle time is 65 seconds. The engine is made to go through five stages in sequence: "theoretical air-fuel ratio-fuel cut-enrichment-enrichment + air replenishment-theoretical air-fuel ratio + air replenishment". Among them, "theoretical air-fuel ratio" is the independent working stage of the engine, the time is 35S; "fuel cut" is the independent working stage of the motor, the time is 10S; "enrichment" is the initial stage of the rapid acceleration stage when the engine resumes work, the time is 5S; "enrichment + air replenishment" is the late stage of the engine acceleration stage, the time is 10S; "theoretical air-fuel ratio + air replenishment" is the braking deceleration stage of the engine.

[0064] Before testing, it is necessary to obtain the target temperature of the catalyst bed. Based on the SRC temperature collected from the actual vehicle, the equivalent aging temperature of the engine bench is calculated using the Arrhenius formula, with a target endurance time of approximately 150-200 hours.

[0065] The catalyst aging performance test bench includes: engine, dynamometer, ECU (Electronic Control Unit), water temperature cooling system, oil cooling system, measurement and control system, secondary air supply system, data acquisition components, etc.

[0066] The engine, as a heat source and exhaust gas source, includes a cylinder, an air intake unit disposed at the top of the cylinder to introduce air into the cylinder, an exhaust unit disposed at the bottom of the cylinder to discharge the exhaust gas after combustion, and a rotating unit disposed inside the cylinder to output power;

[0067] The dynamometer uses an eddy current dynamometer or an electric dynamometer. It is generally composed of a brake, a force measuring mechanism, a speed measuring device, and an adjustment and control system. It measures torque based on the principle that the action torque and the reaction torque are equal in magnitude and opposite in direction. Therefore, the measured torque can be indicated by the rotational torque acting on the dynamometer (i.e., the brake housing reaction torque).

[0068] ECU, the function of ECU is mainly to calculate, process and judge the input information from the air flow meter and various sensors according to the programs and data in its memory, and then output instructions to provide an electric pulse signal of a certain width to the injector to control the amount of fuel injection.

[0069] The main function of the water cooling system is to absorb and remove the heat inside the engine through circulating coolant, and then dissipate the heat to the external environment to ensure that the engine operates within the appropriate operating temperature range. The cooling system also includes other key elements, such as water jackets and water pipes. The water jackets in the engine block and cylinder head are responsible for introducing coolant directly into the engine, and the temperature of the engine is reduced by the circulation of coolant. The water pipes are responsible for connecting various components to ensure the smooth flow of coolant.

[0070] The oil cooling system is a device specially designed to reduce the temperature of the engine oil. When the engine oil circulates inside the engine, it absorbs and removes the heat generated by the engine parts. If the engine oil temperature is too high, its lubrication performance and ability to protect the engine will decrease, and it may even cause engine failure.

[0071] The measurement and control system is a self-developed system that uses Labview software to efficiently control the aging test and collect data in real time. Its data acquisition system uses boards produced by NI to collect voltage and current data and obtain data from various corresponding sensors.

[0072] The secondary air supply system is located at the intake end of the catalyst. During the aging cycle, a certain amount of air is supplied to the inlet of the catalyst and converted into a certain concentration of oxygen.

[0073] The front oxygen sensor and the rear oxygen sensor are located at the inlet and outlet of the catalyst respectively, and measure the volume percentage of oxygen concentration in %.

[0074] The exhaust flow meter measures the exhaust flow of each aging pipeline in g / s.

[0075] Multiple temperature sensors measure the catalyst inlet temperature, bed temperature, and outlet temperature in °C. In particular, the bed temperature is equivalently calculated using the Arrhenius formula to calculate the equivalent vehicle endurance mileage.

[0076] The control parameters of the catalyst bed temperature, oxygen concentration, air-fuel ratio, etc. in the catalyst bench aging cycle test are shown in Table 1. Table 1 is the control parameters in the aging performance test, that is, the test data. The change of the air-fuel ratio of the engine during the aging cycle is shown in Table 1. Figure 3 As shown, the air-fuel ratio at the catalyst inlet is Figure 4 shown.

[0077] Table 1

[0078]

[0079] 2. Catalytic converter oxygen storage performance test, test bench construction Figure 5 shown.

[0080] The catalyst oxygen storage performance test bench includes: aging engine, dynamometer, ECU, oil cooling system, oil temperature cooling system, measurement control system, data acquisition components, etc.

[0081] The engine is the source of high-temperature exhaust gas, the dynamometer provides the engine with appropriate torque, the hot-wire intake flow meter provides the engine with accurate intake flow, the K-type thermocouple monitors and records the catalyst inlet and outlet temperatures, and the open engine calibration equipment MoTeC ECU is used to adjust the engine injection pulse width as needed and achieve

[0082] Lambda data is provided by the wide-range oxygen sensor UEGO (Universal Exhaust Gas Oxygen Sensor) and the HORIBA 730λ air-fuel ratio analyzer, which can more accurately control and collect Lambda values ​​in real time.

[0083] Specifically, the intake air flow meter is a hot wire intake air flow meter with a unit of kg / h. The hot wire is used as a sensor to calculate the intake air volume by measuring the speed and density of the intake air flow. During engine operation, the intake air flow meter will continuously monitor the speed and density of the air flow, and convert the intake air volume information into an electrical signal and transmit it to the ECU. The ECU determines the engine's fuel injection amount based on this signal, thereby adjusting the engine's fuel injection amount and ignition timing.

[0084] The temperature sensor uses a K-type thermocouple to monitor and record the catalyst inlet and outlet temperatures respectively.

[0085] ECU, or electronic control unit, uses the open engine calibration device MoTeC ECU, which can adjust the engine's injection pulse width as needed and control Lambda changes.

[0086] Lambda data collection is provided by UEGO (Universal Exhaust Gas Oxygen Sensor) and HORIBA 730λ air-fuel ratio analyzer, which can more accurately control and collect Lambda values ​​in real time.

[0087] HEGO, located at the intake and outlet ends of the catalyst. The working principle of the narrow-band oxygen sensor is mainly based on the Nernst voltage generated by the oxygen concentration difference in the exhaust gas. When the oxygen concentration in the exhaust gas changes, the oxygen concentration difference between the inner and outer surfaces of the sensor will increase, and the Nernst voltage generated will also increase. Its output signal is in the form of voltage, so it is also called a voltage-type oxygen sensor. The installation positions of various sensors near the catalyst are as follows: Figure 6 As shown, Figure 6 The TWC in the car is a three-way catalytic converter.

[0088] Before determining the calculation method of oxygen storage and release, the working principle of the oxygen sensor is introduced below. The oxygen ion concentration in the atmosphere and the zirconium dioxide ceramic body equivalent to the solid electrolyte form an oxygen ion concentration battery, namely the Nernst principle. Near lambda = 1, the oxygen sensor on the exhaust side will have a step-like change in the voltage signal. According to the oxygen content in the exhaust, the voltage of the oxygen sensor can reach 0.8-1.0V in a rich mixture (lambda < 1), and only about 0.1V in a lean mixture (lambda > 1). In the process of the mixture changing from rich to lean or from lean to rich, the output voltage of the oxygen sensor is 0.45V-0.5V.

[0089] Figure 7 This is a schematic diagram of the data from the catalyst oxygen storage test bench test. Figure 7 As can be seen in the figure, the lambda = 1 measured by UEGO and the output voltage of the front oxygen sensor is 0.45V at almost the same time. Since the voltage signal of the oxygen sensor corresponds to the oxygen concentration in the exhaust gas, it can be roughly considered that Figure 7 The vertical axis is the mass of oxygen passing through the catalyst per unit time, in mg / s. The horizontal axis is the oxygen storage time of the catalyst (△t is the time difference when the output voltage of the front oxygen sensor and the rear oxygen sensor are both 0.45V). The rectangular area formed by the voltage signals of the front and rear oxygen sensors is the oxygen storage capacity of the catalyst, in mg.

[0090] Since the air-fuel ratio window of the catalyst that simultaneously meets the conversion efficiency of the three gaseous pollutants of more than 80% is relatively narrow, at Lean AFR (lean air-fuel ratio), the conversion efficiency of nitrogen oxides NOx drops rapidly, while the conversion efficiency of carbon monoxide CO and unburned hydrocarbon compounds HC compounds hardly drops; at Rich AFR (rich air-fuel ratio), the conversion efficiency of CO and HC compounds drops significantly, and the conversion efficiency of NOx drops slightly. The method used to calibrate the oxygen storage capacity of the catalyst for the whole vehicle is the fluctuation of the air-fuel ratio from rich to lean, that is, to test the ability of the catalyst to dynamically store oxygen. This measurement method focuses on the emission of NOx. As for the fluctuation of the air-fuel ratio from lean to rich, that is, the ability of the catalyst to dynamically release oxygen, the vehicle calibration strategy does not put forward relevant requirements. When the air-fuel ratio changes from lean to rich, the release of oxygen by the oxygen storage material is conducive to the conversion of CO and HC compounds.

[0091] Since the OBD items of the National VI emission regulations use common limit values ​​for non-methane hydrocarbons NMHC and NOx, this bench test adds a test of dynamic oxygen release from the catalyst based on the simulation of the vehicle OSC test, i.e. dynamic oxygen storage. The test data is as follows: Figure 8 As shown, Figure 8 This is a schematic diagram of the data from the oxygen storage test bench for the catalyst. Figure 8 It can be seen that, like the dynamic storage of oxygen, the rectangular area formed by the voltage signals of the front and rear HEGO oxygen sensors is the amount of oxygen released by the catalyst.

[0092] In general, the embodiments of the present application can test the rapid aging cycle of the engine bench at different temperatures, find more reasonable catalyst rapid aging conditions suitable for different hybrid modes, and examine bench evaluation methods of different oxygen storage and oxygen release. Under the optimal conditions, the efficiency of engine bench testing is improved to meet the R&D verification needs of customers, while ensuring that the failure mode remains unchanged and the reliability of the test is ensured. In addition, a more scientific and reasonable evaluation method of bench aging, oxygen storage, and oxygen release is used to effectively monitor the post-processing of hybrid vehicles.

[0093] The catalyst performance test bench proposed in the embodiment of the present application integrates the engine, catalyst, data acquisition component and host computer to form a complete test bench. The host computer can generate a target test process according to the target performance test requirements of the catalyst and control the entire test process, thereby improving the degree of automation of the test and reducing human intervention. It can also generate performance test results based on the relevant data collected by the data acquisition component, thereby ensuring the accuracy and reliability of the test results, and can generate corresponding test processes according to the target performance test requirements, which is suitable for a variety of test scenarios.

[0094] Next, the catalyst performance testing method proposed in accordance with the embodiment of the present application will be described with reference to the accompanying drawings.

[0095] Fig. 9 It is a flow chart of the catalyst performance testing method of an embodiment of the present application.

[0096] like Fig. 9 As shown, the catalyst performance test method is tested using the above catalyst performance test bench, comprising the following steps:

[0097] In step S101, a target test process is generated according to the target performance test requirements of the catalyst.

[0098] Among them, the target performance test requirements include: aging performance test requirements and oxygen storage performance test requirements; the target test process has been explained above and will not be repeated here.

[0099] It is understandable that the embodiments of the present application can generate a target test process based on the target performance test requirements of the catalyst to facilitate subsequent testing.

[0100] In step S102, the engine and the catalyst are controlled to run a test according to a target test procedure.

[0101] In step S103, after the test is completed, a performance test result of the catalyst is generated according to relevant data of the engine and the catalyst.

[0102] It can be understood that the embodiments of the present application can generate performance test results of the catalyst based on relevant data of the engine and the catalyst after the test is completed. For example, the performance of the catalyst can be evaluated based on the oxygen storage and release capacity of the catalyst, the bed temperature of the catalyst, the inlet and outlet temperatures, the oxygen concentrations at the inlet and outlet, the exhaust flow rate, etc. Specifically, the data collected after the test can be compared with the data before the test.

[0103] It should be noted that the aforementioned explanation of the catalyst performance test bench embodiment is also applicable to the catalyst performance test method of this embodiment, and will not be repeated here.

[0104] According to the catalyst performance testing method proposed in the embodiment of the present application, a target test process can be generated according to the target performance testing requirements of the catalyst, and the engine and catalyst can be controlled to run the test according to the target test process, and after the test, the performance test results of the catalyst can be generated according to the relevant data of the engine and the catalyst, thereby realizing the performance test of the catalyst.

[0105] Fig.10 A schematic diagram of the structure of the host computer provided in the embodiment of the present application. The host computer may include:

[0106] A memory 1001 , a processor 1002 , and a computer program stored in the memory 1001 and executable on the processor 1002 .

[0107] When the processor 1002 executes the program, the catalyst performance testing method provided in the above embodiment is implemented.

[0108] Furthermore, the host computer also includes:

[0109] The communication interface 1003 is used for communication between the memory 1001 and the processor 1002 .

[0110] The memory 1001 is used to store computer programs that can be executed on the processor 1002 .

[0111] The memory 1001 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0112] If the memory 1001, the processor 1002 and the communication interface 1003 are implemented independently, the communication interface 1003, the memory 1001 and the processor 1002 can be connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Fig.10 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0113] Optionally, in a specific implementation, if the memory 1001, the processor 1002 and the communication interface 1003 are integrated on a chip, the memory 1001, the processor 1002 and the communication interface 1003 can communicate with each other through an internal interface.

[0114] The processor 1002 may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0115] An embodiment of the present application also provides a vehicle, including a catalyst tested using the above catalyst performance testing method.

[0116] An embodiment of the present application also provides a computer-readable storage medium on which a computer program or instruction is stored. When the computer program or instruction is executed by a processor, the catalyst performance testing method as described above is implemented.

[0117] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0118] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0119] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0120] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one or a combination of multiple of the following technologies known in the art: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0121] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

Claims

1. A catalyst performance test bench, characterized in that: include: engine; A catalyst disposed on an exhaust pipe of the engine; A data acquisition component, used for acquiring relevant data of the engine and the catalyst; The host computer is used to generate a target test process according to the target performance test requirements of the catalyst, control the engine and the catalyst to run according to the target test process, and after the test, generate a performance test result of the catalyst according to the relevant data of the engine and the catalyst.

2. The catalyst performance test bench according to claim 1, characterized in that: The data acquisition component includes at least one of a first temperature sensor, a second temperature sensor, a third temperature sensor, a front oxygen sensor, a rear oxygen sensor, a wide-range oxygen sensor, an exhaust flow meter, and an intake flow meter.

3. The catalyst performance test bench according to claim 2, characterized in that: The target performance test requirements include aging performance test requirements and oxygen storage performance test requirements, wherein: If the target performance test requirement is the aging performance test requirement, the data acquisition component includes the first temperature sensor, the second temperature sensor, the third temperature sensor, the front oxygen sensor, the rear oxygen sensor, the wide-range oxygen sensor and the exhaust flow meter, and the relevant data includes at least one of the bed temperature of the catalyst, the air inlet and outlet temperatures of the catalyst, the air inlet and outlet oxygen concentrations of the catalyst, the excess air coefficient of the engine, and the gas flow rate discharged from the catalyst; If the target performance test requirement is the oxygen storage performance test requirement, the data acquisition component includes the front oxygen sensor, the rear oxygen sensor, the wide-range oxygen sensor and the intake flow meter, and the relevant data includes at least one of the intake flow of the engine, the excess air coefficient of the engine, and the oxygen concentration of the inlet and outlet of the catalyst.

4. The catalyst performance test bench according to claim 1, characterized in that: Also includes: The secondary air supply system arranged at the air inlet of the catalyst is used to supply air to the catalyst to adjust the oxygen concentration of the exhaust gas in the air inlet of the catalyst.

5. The catalyst performance test bench according to claim 3, characterized in that: If the target performance test requirement is the oxygen storage capacity performance test requirement, the host computer is further used to: acquiring voltages generated by the front oxygen sensor and the rear oxygen sensor based on the oxygen concentration; respectively determining a sudden change time when the voltage of the front oxygen sensor and the rear oxygen sensor changes from a first threshold value to a second threshold value; Calculating the oxygen storage amount and oxygen release amount of the catalyst based on the excess air coefficient, the intake air flow of the engine, the sudden change time of the voltage of the front oxygen sensor, and the sudden change time of the voltage of the rear oxygen sensor; A performance test result of the catalyst is generated according to the oxygen storage amount and / or the oxygen release amount.

6. The catalyst performance test bench according to claim 1, characterized in that: The target test process is: Acquiring a target test phase of the catalyst, wherein the target test phase includes the first to fifth phases; Get the test data corresponding to each test stage; generating a target test instruction based on the target test phase and the corresponding test data; The engine and the catalyst are controlled to perform the first to fifth phase tests in sequence according to the target test instruction.

7. A catalyst performance testing method, characterized in that: The catalyst performance test bench according to any one of claims 1 to 6 is used for testing, comprising the following steps: Generate a target test process based on the target performance test requirements of the catalyst; Controlling the engine and the catalyst to run the test according to the target test process; After the test is completed, a performance test result of the catalyst is generated based on relevant data of the engine and the catalyst.

8. A host computer, characterized in that it includes: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the catalyst performance testing method as claimed in claim 7.

9. A vehicle, characterized in that: It includes a catalyst tested by the catalyst performance testing method as described in claim 7.

10. A computer-readable storage medium having a computer program or instruction stored thereon, characterized in that: The computer program or instructions are executed by a processor to implement the catalyst performance testing method as claimed in claim 7.

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