Design Of Automobile Engine Fault Diagnosis Training Platform

With the professional development and progress of professional talents in the automobile industry of higher vocational education,the former training platform of passenger car engine can not meet the needs of education.In view of the existing problems in the current domestic electronic control engine training platform and the characteristics of higher vocational education,the intelligent system of the electronic control engine training platform is discussed,and a new automotive engine electronic control training platform is developed.At present,the development and application of motor engine in control technology is very rapid.The failure of electronic control engine is no longer only the faults of oil,circuit and machinery,but also the fault part of sensor,ECU,actuator or circuit,especially the electronic point fire system of automobile fuel injection.This system is used as the whole engine.The central part of the electric control part is very important and difficult for many automobile maintenance workers and vocational college students.In order to improve students' practical ability,discrimination and the essence of induction,they will assist students in induction of scientific experiments and practical skills.In order to improve the planning technology of electronically controlled engine training platform and improve the function of the electronically controlled engine training platform,this paper discussed and developed it.Based on the analysis of the structure of all kinds of engine electronic control system,the common faults of engine's sensors and actuators are put forward.Through the analysis of the structural characteristics of the engine,the overall design and layout of the electronic control test-bed is carried out.The electronic circuit and diagnostic terminal were studied,and the training console control panel was designed.The modular test plan is used to build intelligent test equipment.The ignition circuit,starting circuit,fuel injector circuit,oil pump circuit,main relay circuit,idle speed control circuit,all kinds of circuit breakers are set up with the control relay of AT89C51 single chip microcomputer,and the fault setting of sensor signals can also be set.The circuit control scheme of decoder,LCD and keyboard controller based on AT89C51 MCU is completed,and the human-machine interaction function is realized by WINCC.Through the idle test,the accelerated test and the start test of the engine electronic control test rig,the original test and the fault setting test were carried out.The feasibility ofthe intelligent fault plan was verified and the expected effect was achieved.In this paper,the basic structure and working principle of the engine are developed.(1)The necessity of developing the electrical control system fault simulation training vehicle test bed is discussed.From the analysis of the status of automobile maintenance specialty and the status of automobile professional training and education,the present situation of the current training and education at home and abroad is understood,and the significance of developing and utilizing the motor vehicle engine of the electric control platform is put forward.(2)Through in-depth study of the basic structure and working principle of the engine electronic control system.The causes and diagnostic methods of common faults of engine are analyzed,which provides a theoretical basis for the simulation of common faults of electronic control system.(3)A fault simulation method of engine electronic control system is put forward.The fault analog circuits of fault analog circuits and switch control are used to develop and control the fault analog circuits of various sensors,actuators,control unit ECU and electronic circuits,such as damage,short circuit,circuit breakage,bad contact,signal missing or signal deviation.We completed the simulation and demonstration of the common faults of the electric control system of the engine outside platform.(4)The fault simulation test rig of engine electronic control system is developed.According to the reclosing method of analog circuit and switch control fault mode,the fault setting can be completed only through the switching of the switch control circuit,and the electrical signals of each sensor,actuator and engine control unit can be tested directly on the panel to complete the fault analysis,detection and cleaning,and complete the fault.(5)Test and test the fault simulation test bed of engine electronic control system,and use this training platform to simulate the typical fault of engine electronic control system.The test results show that the training platform developed in this paper can reliably simulate and demonstrate the expected fault,and it has clear principle,strong intuition,safety and reliability,and has practical meaning to engine fault diagnosis and diagnosis training.