PCB的辐射发射诊断方法及抑制措施分析

The Diagnostic Methods and Control Measures Analysis of PCB's Radiaton Emission

PCB板的辐射发射问题一直是PCB的电磁兼容问题的重点和难点,查阅大量文献发现国内对于PCB的辐射发射问题的研究一直停留在仿真分析,然而,电磁兼容是个实验性很强的学科,仿真结果跟实际测试结果往往差距甚远,并无太大指导意义,因此很有必要根据现有实验设备,搭建一个针对PCB的辐射发射问题进行诊断的测试平台.本文首先使用差模辐射和共模辐射解释系统辐射发射问题,又将线缆上共模电流的产生归结为电压驱动型和电流驱动型两种模型,在此基础上建立了一套用于电子控制器辐射发射问题诊断的方法.试验证明该方法可以准确定位导致出现辐射发射问题的电路板设计缺陷,具有很强的参考价值.

The PCB＇s radiation emission is always the key and the most difficult point of electromagnetism compatibility of PCB.But the PCB＇s radiation emission problems research still remained in the simulation analysis stage in China.The simulation results are far from the actual test results and have little guidance.Therefore,according to the existing lab equipment,it is necessary to build a test platform for the PCB＇s radiation emission problem diagnosis.In this paper,differential mode radiation and common-mode radiation were used to interpret system radiation emission problems,and attribute the generation of cable common-mode current to voltage driving type and current drivers type.Based on this set,an electronic controller radiation emission problem diagnosis method was set up.Test shows that this method can accurately orientate the circuit board design flaw leading to radiation emission problems,and the result has a strong reference value.