| The automotive industry is developing rapidly in recent years, and has already made main contribution to national economy. Today the engine researchers and engineers have to face two social problems which are the energy crisis and environment pollution. The aim of gasoline engine design is to reduce fuel consumption greatly while satisfying the emission regulation and having a long durability. Direct injection stratified charge technology is proved to be a valuable solution in this point because it combines the advantages of diesel engine and gasoline engine. Comparing to the general gasoline engine, the lean burn engine has large A/F,and high compression ratio, and low burn temperature. The lean combustion engine is more efficient.On the other hand, the vehicle electronic control technology as the key of engine control has changed more and more popular in the world. This key technology is the unique technology fitting for the require of vehicle usage in the modern society for it had made a good progress in the power, economic, emission etc. . It is necessary to keep innovating and developing electronic control products of engine in automotive industry. At present, domestic area of ECU products are blank, so researching and developing electronic control products of engine independently is imperative in China.The author focused on the key part of EA888 gasoline direct injection engine electronic control system(ECU, Electronic Control Unit) in this thesis. The main work included:1. Electronic control system of EA888 1.8L TFSI engine was completely analyzed at first. As well as the function of ECU, the characteristic of sensor output signals and actuator driving signals were obtained by referring to literature, signal sampling and testing. Then the plan of designing, the principle ECU software and hardware were established.2. The hardware circuit of principle ECU was well designed. This part included: micro-processor determination, sensor signal processing circuit design, actuator driving circuit design and system circuit design for micro-controller. Test result showed that sensor signal processing circuit is characterized with high precision and good anti-interference, the actuator driving circuit is characterized with high integration and good reliability, and the micro-controller is characterized with rapid calculation and excellent real-time operation.3. The software program of principle ECU was developed. In this stage, program was developed in top-down mode. And control strategy was made considering both experiment data from dynamometer test and basic knowledge of internal combustion. The completed module function consisted of crankshaft and camshaft signal control logic, spark ignition control, fuel injection control and start period control. Structure design, based on modularization, made the program well-organized, highly-reliable, great-readable and movable etc.4.The software and hardware of principle ECU was tested with simulation equipment and then dynamometer test was run with EA888 1.8L TFSI engine. At first, simulation test platform is configured to debug the software and hardware of principle ECU by using simulation signal generator. After the reliability and feasibility were verified by the dynamometer test of idle speed control, the principle ECU was matched with the engine to continue dynamometer test.
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