汽车线束电感性串扰动态变化的预测

Prediction of variation of inductive crosstalk in automotive cable bundles

为了预测汽车运动时其线束的电感性串扰动态变化,建立了线束的电感性串扰最好、最差情况预测模型和蒙特卡罗方法改进模型。根据导线在线束内几何布置的极限位置,得到电感性串扰的最好、最差情况预测区间;基于蒙特卡罗法得到电感性串扰数学期望值,在80%置信水平下求得期望值的置信区间,置信区间即为改进的预测区间。与EMC Studio仿真软件结果的比较显示,低于5MHz时,所选位置的线束串扰都在长度为5dB最好、最差预测区间内,多数位置线束串扰在长度为3dB蒙特卡罗改进区间内,改进的预测区间缩小了40%;高于5MHz时,电尺寸趋于电大,误差变大。建立的两个汽车线束电感性串扰预测模型能够根据不同精度要求快速预测电感性串扰动态变化。

In order to predict the variation of inductive crosstalk in the cable bundles as the automobile was in motion,both the prediction model of the inductive crosstalk of the best/worst cases and the amended model by Monte Carlo method were established.According to the extreme positions of wires in the cable bundles,the prediction intervals of the inductive crosstalk of the best/worst cases were defined.By using the Monte Carlo method,the mathematical expectation of the inductive crosstalk was obtained,and the confidence interval for the expectation was defined under the circumstance of 80% confidence level.Here,the confidence interval was the amended prediction interval.By comparison with the results from EMC Studio electromagnetic simulation software,it is shown that the cable bundle crosstalks in all selected positions are in the best/worst case interval and most of them are in the amended interval when the frequencies are lower than 5 MHz.The length of the amended interval has decreased by 40%.Moreover,the electrical dimensions tend to electrically large and the error also increases when the frequencies are higher than 5 MHz.It concludes that the both models are simple and convenient to predict the inductive crosstalk rapidly according to different accuracy requests.