Research On Electromagnetic Compatibility Of Automobile Ignition System

With extensive application of various electronic circuits and electronic technology in the fields of family, industry, traffic, national defence, Electromagnetic Interference (EMI) has already become the problem that must be considered in the design process of modern electrical engineering. Since 1860,when electrical energy was used to ignition, the automobile started to interference the around electromagnetic environment. The automobile ignition system is the greatly strengthened electromagnetism noise source. Electromagnetic wave radiation, which is caused by high-voltage electric spark igniting the automotive engine, has electromagnetic interference to car radio system and ambient electromagnetic environment. Spark plugs and high-voltage ignition wire are main interference sources of the automobile spark-ignition system. Based on the analysis of the automobile electromagnetic compatibility standard and the principle of the automobile ignition system, we researched the noise current, which come from the ignition system. The method on suppressing electromagnetic interference caused by automobile spark-ignition system is given and it has no influence on igniting characteristic.The paper first has made the brief elaboration to the automobile electromagnetic compatibility standard and the automobile electromagnetic compatibility research content. After that thoroughly analysis was discussing the automobile ignition system structure and the work process, has produced a simple model of the ignition system which included the secondary equivalent circuit. Then, the author earnestly analyzed mechanism of the automobile ignition system to produce the electron magnetic interference, and has established the spark plug and the secondary return route equivalent circuit model in this foundation, and the simulation studies has produced in the electromagnetism harassment spark electric current as well as the high-voltage ignition wire electric current. The author has discussed in the parameter of the secondary return route to harass the electric current the influence, thus obtained some suppression electromagnetism harassments the method. The paper finally also designed some experimental which directed toward ignition systems electro magnetic compatibility according to the standard to conduct the research, obtained some valuable results from the experimental study angle.This article not only produced the electron magnetic interference mechanism to the automobile ignition system to conduct the research, but also aimed at it to produce disturbs the most main spark plug and the secondary return route has established the equivalent circuit model, and has carried on the simulation analysis, finally has also obtained some through the experimental study in the project actual center valuable result. The present paper work may provide the certain theory instruction for the automobile ignition system electro magnetic compatibility design, has the actual reference value.