Simulation Study Of Electromagnetic Environment For Vehicle (Radiation And Anti-interference)

With the development of modern science and technology，more and more electronic products areused in automotive and the electromagnetic compatibility problems has become increasingly severe. Itmakes the sensitive electronic equipments on the automobile unable to run normally or even fail towork, affecting the reliability and traffic safety. The development of electric vehicles makes it evenworse. National standard has made strict requirements for electromagnetic radiation of electric vehicle.Therefore, this paper takes electric vehicle (EV) as the object of study and makes research on itsinternal electromagnetic environment, the main research contents are as follows:(1) Three-dimensional model and mesh model of EV car body suitable for electromagneticenvironment simulation were established and the accuracy of the model was verified through differentmethods of calculation.(2) The crosstalk of harness in EV was analyzed based on the multi-conductor transmission linetheory. The crosstalk of different situations including two-wire crosstalk, multi-wire crosstalk andcrosstalk in EV was simulated. The impact of wire length, diameter, shape and other factors oncrosstalk was analyzed and several ways to reduce crosstalk was also proposed.(3) The conducted interference and radiated interference of Bi-directional DC/DC converter inEV were simulated. Simulation tests of conducted interference of Bi-directional DC/DC converterwere made using the conducted interference measurement methods in GB18655-2008after insert aLISN. The testing results were compared with the standard limits. The effect of filter on reducingconducted interference of Bi-directional DC/DC converter was verified. The radiation ofBi-directional DC/DC converter in EV was simulated. The curve of electromagnetic field intensity atdifferent points inside the EV was obtained.(4) The radiation of different intensity of lightning in different locations and the couplingbetween lightning and the harness in the EV were simulated using double exponential model oflightning return stroke current based on the method of moment. The electromagnetic shieldingeffectiveness of the car body was calculated and some methods to increase the shielding effectivenessof the EV were proposed. Finally, the electromagnetic field distribution inside the car was obtainedunder a variety of excitations.In summary, the use of automotive design and development process of automotiveelectromagnetic environment simulation, not only can play the role of predicting the carelectromagnetic radiation and electromagnetic fields in time to avoid excessive radiation, but alsoshortening the development cycle, saving research and development costs to ensure the quality ofautomotive electromagnetic compatibility.