Research Of Electronic Control Injection System For A Small Two-stroke Kerosene Engine

This paper's research object is a two-stroke gasoline engine. Based on the original electronic control system, its main task is to design an electronic control unit for the fuel injection system, which uses kerosene as the substitute fuel.The main work of this paper is as follows:1. The influence of the engine brought by the kerosene burning is analyzed based on physicochemical properties of kerosene, in which the power performance of the engine is discussed emphatically. Based on the heat value of fuel mixture, the adjustment coefficient calculation of the kerosene basic injection pulse is accomplished. And the kerosene basic injection pulse is got from the original engine.2. According to the feature of electronic control fuel injection system and the physicochemical properties of kerosene, the ECU control strategy of the fuel injection system is designed. Considering the related sensor signals, the correction algorithm for injection pulse is also proposed.3. MC9S12DP512 is selected as the controller chip and its working circuit is given. The signal processing circuits of sensors and the drive circuits of actuators are both designed. And the calibration work for all sensors is also completed. The interference sources and their transport paths are studied. The hardware anti-interference measures are adopted and the hardware development of ECU is completed.4. Regarding to the proposed control strategy, the modularization design method is introduced into the software design. The design idea and implementation method of the system software are mainly discussed, and some software anti-interference measures are also taken. After that, the design of the software is completed.5. The ECU Simulation experiments are accomplished and the results show that all function modules of the designed ECU can reach the desired functions.6. To validate the working performance of the designed ECU, the engine bench experiments are carried out. The results show that the designed control strategy and the calculated injection MAP can meet the control demand of the kerosene engine. The designed ECU can work reliably with strong anti-interference ability. And the comprehensive performance is well approached the control effect of the original ECU.