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CN-122014465-A - Engine control device and humidity measurement method

CN122014465ACN 122014465 ACN122014465 ACN 122014465ACN-122014465-A

Abstract

The application relates to the technical field of vehicles, and provides an engine control device and a humidity measurement method; the method comprises the steps of detecting actual pump current of a wide-range front oxygen sensor in a current state, obtaining theoretical pump current of the wide-range front oxygen sensor, comparing a current difference value D ip between the actual pump current and the theoretical pump current with a set threshold value, entering the next step if the current difference value is larger than the set threshold value, collecting a natural gas injection quantity coefficient and a knock intensity indication coefficient when an engine is in a humidity detection working condition, obtaining a knock difference value and a natural gas injection quantity difference value by difference with corresponding preset standard values, calculating relative humidity of engine intake air, and obtaining target humidity of the engine intake air by searching a preset conversion table of the relative humidity and the absolute humidity. The application has the technical problems of complicated structure, high cost and insufficient reliability due to the fact that an air intake oxygen sensor and an air mass flow sensor are additionally arranged in the traditional engine humidity measurement.

Inventors

  • LIU LIN
  • WU JIAN
  • XU JIANFEI
  • YANG QIANG

Assignees

  • 一汽解放汽车有限公司

Dates

Publication Date
20260512
Application Date
20260105

Claims (10)

  1. 1. An engine control apparatus, comprising: An intake unit for delivering air for combustion to the engine; The tail gas control unit is used for conveying part of the waste gas to the engine to participate in combustion; a fuel delivery unit for delivering fuel to the engine; The common end of the air inlet unit, the tail gas control unit and the fuel conveying unit is communicated with the mixer; the gas conveyed by the gas inlet unit, the tail gas control unit and the fuel conveying unit is mixed through the mixer and then is input into the engine for combustion; The system also comprises a sensor assembly, wherein the sensor assembly is used for collecting engine operation parameters, and the operation parameters at least comprise pump current, natural gas injection quantity coefficient, knock intensity indication coefficient, atmospheric pressure and ambient temperature in the wide-range oxygen front sensor; The ECU is electrically connected with the sensor assembly; and the ECU calculates the target humidity of the air intake of the engine by adopting a preset control method based on the operation parameters.
  2. 2. The engine control device according to claim 1, characterized in that the intake unit includes: the system comprises a turbocharger and an intercooler which are sequentially communicated through a pipeline, wherein the turbocharger comprises a gas compressor and a turbine, the gas compressor is used for conveying inlet gas, and the turbine is used for conveying exhaust gas; the output end of the intercooler is communicated with the mixer, and an electronic throttle valve is arranged on a pipeline between the output end of the intercooler and the mixer; The air is pressurized by a compressor of the turbocharger and then is conveyed to the intercooler for cooling, the air is conveyed to the mixer for mixing through the intercooler, the mixed gas is conveyed to a combustion chamber of the engine for combustion through the intake manifold, and an intake air temperature sensor is arranged on a pipeline between the intake manifold and the mixer.
  3. 3. The engine control device according to claim 2, wherein, The exhaust gas control unit includes: The system comprises an EGR cooler and an EGR flow control unit which are communicated in sequence, wherein the input end of the EGR flow control unit is communicated with an exhaust manifold of an engine, and the output end of the EGR flow control unit is communicated with a mixer and is used for adjusting the amount of exhaust gas entering the mixer.
  4. 4. The engine control device according to claim 3, wherein, The fuel delivery unit includes: the natural gas inlet channel injection assembly and the natural gas pressure reducer are sequentially communicated, and the natural gas inlet channel injection assembly is used for inputting natural gas into the mixer.
  5. 5. The engine control device of claim 4, wherein the sensor assembly includes at least: A wide-area front oxygen sensor, an atmospheric pressure sensor, an ambient temperature sensor, a knock sensor, and a natural gas flow sensor; wherein the wide-range front oxygen sensor is arranged on a downstream pipeline of a turbine of the turbocharger and is used for detecting the oxygen content in the tail gas of the engine according to the internal pump current variation; The atmospheric pressure sensor is arranged inside the ECU; The knock sensor is arranged on one side surface of the engine body and is used for detecting a knock intensity indication coefficient of the engine; The natural gas flow sensor is arranged in the natural gas inlet channel injection assembly and is used for collecting natural gas injection quantity coefficients.
  6. 6. The engine control device according to claim 5, wherein, When the engine is in an operation condition, the ECU is used for closing the fuel conveying unit and the tail gas control unit to stop conveying fuel and waste gas, and conveying air to a downstream pipeline of the turbine through the air inlet unit sequentially through the engine and the exhaust manifold, and measuring the oxygen content of the air through the pump current of a wide-range front oxygen sensor on the downstream pipeline; The pump current based on the wide-range front oxygen sensor adopts a preset control method to calculate the target humidity of the engine air intake.
  7. 7. A method for measuring the humidity of an engine, characterized in that it is applied to the device according to any one of claims 1-6, said method comprising the steps of: s1, detecting the actual pump current IP of a wide-range front oxygen sensor in a current state in real time when a vehicle is in an operation condition, wherein the operation condition at least comprises a reverse towing condition and a long downhill condition; S2, acquiring the altitude of the current position of the vehicle based on the atmospheric pressure, and acquiring the theoretical pump current of the wide-area front oxygen sensor by searching a preset reference table based on the altitude; S3, comparing a current difference D ip between the actual pump current IP and the theoretical pump current with a set threshold, and if the current difference D ip is larger than the set threshold, entering the next step; s4, when the engine is in a humidity detection working condition, acquiring a natural gas injection quantity coefficient and a knock intensity indication coefficient, and obtaining a knock difference value and a natural gas injection quantity difference value by differentiating the natural gas injection quantity coefficient and the knock intensity indication coefficient with corresponding preset standard values, wherein the humidity detection working condition at least comprises a medium-load working condition and a high-load working condition; s5, calculating the relative humidity of the air inlet of the engine through a weighted calculation formula based on the acquired current difference value, knock difference value and natural gas injection quantity difference value; And S6, acquiring target humidity of engine air intake by searching a preset conversion table of relative humidity and absolute humidity based on the acquired relative humidity, the current ambient temperature and the atmospheric pressure.
  8. 8. An electronic device comprising a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other via the communication bus, characterized in that the memory stores a computer program which, when executed by the processor, causes the processor to perform the steps of the method as claimed in claim 7.
  9. 9. A computer readable storage medium, characterized in that a computer program executable by an electronic device is stored which, when run on the electronic device, causes the electronic device to perform the steps of the method according to claim 7.
  10. 10. A simulation platform, comprising: an electronic device for implementing the steps of the method of claim 7; a processor running a program, the data output from the electronic device when the program is run performing the steps of the method of claim 7; a storage medium storing a program which, when run, performs the steps of the method of claim 7 on data output from an electronic device.

Description

Engine control device and humidity measurement method Technical Field The application relates to the technical field of vehicles, in particular to an engine control device and a humidity measurement method. Background Driven by national six-natural gas emission regulations and natural gas fuel economy, all large host factories in China have put forward natural gas national six-engine with different technical routes, and corresponding national six-natural gas vehicles are marketed in a large quantity. Currently, the six natural gas engine technical scheme in the main stream of China is equivalent combustion, high-pressure EGR cooling and single-point injection of an air inlet channel. In the actual vehicle use process, users gradually find that compared with the direct injection lean combustion mode of a diesel engine, the power output aspect of single-injection equivalent combustion of an air inlet channel is greatly affected by environmental changes, and particularly under the use condition of high air inlet humidity, the power loss is obvious. Analysis of a large number of bench test data shows that the influence mechanism of high humidity on power has two aspects, namely, the reduction of oxygen content in intake air along with the improvement of intake air humidity can lead to the reduction of total intake engine oxygen under an equivalent mode taking air quantity as a control target, so as to lead to the reduction of natural gas injection quantity, and the increase of water content in intake air along with the improvement of intake air humidity can lead to the phase change to improve the combustion EGR rate of an engine, slow down the combustion speed of natural gas in a cylinder and weaken knocking, but the combustion heat release efficiency is reduced under the condition of constant corresponding ignition angle, and the gas consumption and the torque output of the crankshaft end of the engine are influenced. In order to detect the ambient humidity, the existing means generally directly adopt a temperature and humidity sensor. And meanwhile, according to the detected humidity, correcting the air inflow and the combustion parameters of the engine. However, the temperature and humidity sensor for the vehicle is relatively expensive on one hand, and the measuring range of 0% -100% relative humidity of the sensor is too redundant for the current application on the other hand. Corresponding bench test data indicate that when the relative humidity of the inlet air is higher than 85%, the power output of the natural gas engine of the current configuration is obviously affected. The relative humidity of the intake air is in the range of 0% -80%, the power output of the engine can be basically maintained unchanged without correcting combustion parameters, wherein the combustion parameters comprise the intake air amount, the ignition angle and the EGR rate. Disclosure of Invention The invention aims to provide an engine control device and a humidity measurement method, which solve the technical problems that an intake air oxygen sensor and an air mass flow sensor are additionally arranged in the traditional engine humidity measurement, and the engine control device is complex in structure, high in cost and insufficient in reliability. The specific scheme is as follows: an engine control apparatus comprising: An intake unit for delivering air for combustion to the engine; The tail gas control unit is used for conveying part of the waste gas to the engine to participate in combustion; a fuel delivery unit for delivering fuel to the engine; The common end of the air inlet unit, the tail gas control unit and the fuel conveying unit is communicated with the mixer; the gas conveyed by the gas inlet unit, the tail gas control unit and the fuel conveying unit is mixed through the mixer and then is input into the engine for combustion; The system also comprises a sensor assembly, wherein the sensor assembly is used for collecting engine operation parameters, and the operation parameters at least comprise pump current, natural gas injection quantity coefficient, knock intensity indication coefficient, atmospheric pressure and ambient temperature in the wide-range oxygen front sensor; The ECU is electrically connected with the sensor assembly; and the ECU calculates the target humidity of the air intake of the engine by adopting a preset control method based on the operation parameters. Optionally, the air intake unit includes: the system comprises a turbocharger and an intercooler which are sequentially communicated through a pipeline, wherein the turbocharger comprises a gas compressor and a turbine, the gas compressor is used for conveying inlet gas, and the turbine is used for conveying exhaust gas; the output end of the intercooler is communicated with the mixer, and an electronic throttle valve is arranged on a pipeline between the output end of the intercooler and the mixer; The air is pressurized by a compressor o