中文摘要：

随着开关电源工作频率不断提高，电磁干扰问题也变得日益严重，结合LLC半桥谐振开关电源的设计实例，首先分析了高频传导干扰对PCB电磁兼容性的影响。在EMC分析中．使用CadenceSPB16．3与AnsoftDe—signer6．1相结合的方法，基于场的原理，建立PCB仿真模型，分析LLC半桥谐振开关电源PCB的电磁兼容特性。其次，根据电磁场近场分布图，对PCB的布局布线加以改进，提高了PCB的电磁兼容特性。最后，仿真结果表明其电磁场强度有较大幅度减小，同时进一步验证了设计阶段中针对PCB改进的合理性。

英文摘要：

As the working frequency of the switching power supply is continuously increasing, the electromagnetic interference problem becomes more and more serious. Firstly, taking the LLC half-bridge resonant switching power supply as an example, the influence of high-frequency conducted interference on the electromagnetic compatibility of PCB was analyzed. Based on field theory, Cadence SPB 16.3 combined with Ansoft Designer 6.1 were used to analyze the EMC of the PCB for the LLC half-bridge resonant switching power supply. Secondly, according to the distribution of the electromagnetic near field, the layout of the PCB was modified to improve the electromagnetic compatibility. Finally, some simulation results were given,and verified the improvement in PCB design.