The Development Of Principle Electronic Control Unit Of Gasoline Engine

The automobile industry is developing rapidly in recent years, and has already made main contribution to national economy. As the energy's shortage and more and more strict environmental policies, it is necessary to keep innovating and developing electronic control products of engine in automobile industry. At present, domestic area of ECU products are blank, so researching and developing electronic control products of engine independently is imperative in China.This paper focused on the key part of gasoline engine electronic control system (ECU, Electronic Control Unit).The main work included: referring to the similar mature products abroad, designing hardware and developing software of principle ECU independently, setting experimental platform for simulation testing and carrying out dynamometer test. The details are as follows:1. Delphi/ITMS-6F electronic control system equipped in SAIL car 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-controller determination, sensor signal processing circuit design, actuator driving circuit design and system circuit design for micro-controller. In addition, the original harness of ITMS-6F is modified in order to fit the principle ECU. 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, fully considering both experiment data from dynamometer test and basic knowledge of internal combustion. The completed module function consisted of 58X 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 479QE 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, the principle ECU was matched with 479QE engine to continue dynamometer test. The test work consists of start performance, warm-up performance and idle stability test.