Real-Time Model Of Natural Gas Engine Construction And Semi-Physical Simulation Based On DSPACE

As a new type of clean energy,natural gas has been widely used in various industries,especially in the engine industry.The development of engine electric control technology can not only improve engine performance,economy,reliability,but also improve the performance of engine.Therefore,the development of the market competitive engine electronic control unit has become the current mainstream research objective.Therefore,the development of the market competitive engine electronic control unit has become the current mainstream research objective.Mode of "V" development of the modern control system is one of the important part of engine research and development,including for ECU hardware in loop test link,real time and accuracy,dynamic response of engine model is the key to influence the control effect and engine performance.Based on the analysis of the current mainstream of natural gas engine control system on the basis of the relevant technology of the hardware in the loop simulation,set up a complete set of hardware in the loop simulation system,including the semi physical simulation experiment,gas engine model,the real-time signal processing module and PC monitor interface semi physical simulation experiment.Using Simulink software modular thought established based on the hardware in loop real-time simulation of natural gas engine zero dimensional points cylinder volume model,under the premise of meeting the accuracy requirement,improve the simulation speed,the model was optimized according to the control requirements of the controller,can reflect the natural gas engine under different working condition in cylinder parameter change and the change of combustion heat release rate,the model can meet the development of electronic control system with different control strategies.This paper mainly studies the modeling methods for natural gas engine cylinder,in view of the real-time model of module partition,zero dimensional combustion model for calculating the heat release rate,air-fuel ratio calculation research,make model on meet the requirements of precision meet the real-time requirement the semi physical simulation experiment.Eventually use dSPACE platform to build the gas engine zero dimensional points cylinder volume model for semi physical simulation experiment,through the analysis of the parameter in cylinder,the final conclusion,the results show that builds the zero dimensional points cylinder volume model can satisfy the real-time and accuracy requirements of semi-physical simulation,the model can reflect the different air-fuel ratio,ignition advance Angle and jet engine under the inhomogeneity of combustion heat release rate and the change of other parameters in cylinder,and the experimental results with real engine test bench data base,show that the model can meet the requirements of semi physical simulation experiment,and meet the engine under different control strategies of engine performance test.Finally,the volumetric method model is compared with the traditional mean model,and the advantages and disadvantages of the two are compared.The real time of the traditional average model is better but cannot reflect the change of the internal parameters of the cylinder.However,the volumetric method model can reflect the change of parameters in the real engine cylinder,although the real-time performance is not as good as the mean model,but it still satisfies the semi-physical simulation experimental conditions.Therefore,the zero-dimensional cylinder volumetric method model is a semi-physical simulation real-time model which meets the development of the electric control system.The research results of this project have great significance for the research and development of natural gas engine control system and the verification of control strategy.