Simulation And Suppression Method Research On Electromagnetic Interference Of Automobile Ignition System

With the rapid development of economy in our country,the automobile industry has been the introduction of new technology and process.Especially in recent years,a large number of complex electronic equipment appears in the automotive industry.Although these devices greatly improve the customer demands,they also bring serious electronic compatibility problems.Long-term research and test results in our country and abroad inside and outside the car imply : The most prominent electromagnetic interference among electromagnetic interference is the ignition system.When the car ignition system work,it produced interference sources not only by its connected wire but also from electromagnetic radiation continuously,which threaten the safety of the vehicle electronic system and make it hard to meet the EMC standard.Thus,in this study,it is very important to study the electromagnetic interference for auto ignition system,through this study we can learn interference effect on overall vehicle system and validate optimization improvement method.In this article we learn the classification of the vehicle ignition system?the working principle and related EMC index.Furthermore,we analysis the principle of electromagnetic interference within the whole vehicle,then we design the simulation model according to the principle.The specific conclusions are described below.(1)From brief introduction of the vehicle ignition circuit principle in the car ignition system,we lay a solid foundation on the basis of analysis the principle of electromagnetic interference.(2)According to the above theoretical knowledge to the current change status during ignition switch work,we can conclude the characteristics of interference,then we raise the suppression method to slow down the transient voltage.(3)Calculate the electric current when breakdown the gap of spark plug,which we can lay the foundation for subsequent simulation.(4)The simulation to the ignition system of high voltage wires can be equated with monopole antenna radiation interference.At the same time the corresponding car model and the antenna model was constructed for the electric field distribution in the vehicle system simulation.Then we analysis of the influence of different factors on the electromagnetic system,such as the location of the conductor placed,different working frequency and load impedance,etc.(5)Simply expounds the related national EMC standards.In accordance with the standards and the existing experiment conditions on the ignition system,we analysis specific examples of the ignition system work waveform,radiation condition of vehicle,system analysis of radiation of receiver.Finally we take corresponding measures to high voltage wires of electromagnetic interference shielding and analysis the actual effect.(6)Before detail analysis of data and comparing the equivalent model which is set up,we finally validate the correctness of the model and provide reference to furthermore improvement of the simulation experiment.The study completed the ignition system in electromagnetic interference test and data calculation,give the conclusions to related automotive electromagnetic shielding design and provide strong theoretical support to the future study.