Research On The Electronic Control System's Development And Its Simulition For Four-Cylinder Gasoline Engine

Electronic control technology is regarded as a significant way to reducethe exhaust emissions and improve the power and economy performance. Andit's also one of important standard to evaluate the level of engine and carindustry. So the development and study of electronic control technology ispaid more attention.Based on tracking of the domestic and alien advanced electronic controltechnology, the electronic control system was researched and developed forfour-clylinder gasoline engine in this dissertation. Primary conclusion includesthese items. First, the reasonable control strategy and algorithm wereestablished. Second, the simulative model of electric control system was set upin Matlab/Simulink environment, in which the feasible control strategy andalgorithm was confirmed by integrated simulation. Then the simulative modelof engine calibration was upbuilt, by which the original MAP of fuel injectionand ignition timing was obtained. Afterward, the detailed design ways ofelectronic control uint (ECU) hardware and software were advanced.In this dissertation, the main innovations and conclusions are as follows:1) Using Fuzzy autotune PID control algorithm to control the idle speedwas a preferable way. And its feasibility and advantage was confirmed bysimulative experiment afterward.2) An improved 4-cylinder 4-stroke gasoline engine model, the air/fuelrato and ignite controller models which were relevant the control strategy wereestablished. By appending fuel dynamic evaporation model to make the enginemodl can be use to simulate the stable state and transient state. An arctangentfunction transform was improved to simulate the output characteristic ofoxygenic sensor, which made the closed loop control for the air/fuel ratio canbe simulated in the engine model. The modularize method was adopted incontroller's upbuilding, which could be the reference for control sorftware'sdesign.3) Engine simulative calibration model was established, in which thesimulated calibration experiment was taken and the primal oil MAP data wasobtained. And artificial intelligence neural network ways, which can increase the efficiency to get the original MAP data, were advanced by comparison andtheory analysis.4) A simulated engine calibration system was developed, which canaccomplish model setting, simulative calibration and original MAP to certaintype of engine conveniently.5) A high performance 16 bit microprocessor MC9S12DP256, producedby Motorola, was adopted as the CPU of the ECU. Reliable simple ways wereintroduced to design the signal processing and driver circuit, which can meetthe demand of the present ECU system of gasoline engine.