显卡散热器电磁辐射仿真和结构优化

针对显卡散热器设计越来越大，电磁干扰（Electromagnetic Interference，EMI）易超标的问题，采用ANSYS HFSS建立不同接地方式的某显卡散热器模型，分析所带来的辐射变化；计算散热器与PCB间的寄生参数，优化散热器形状来改变辐射方向，从而有效降低电磁辐射.在屏蔽暗室中进行测试验证，结果表明，优化后显存时钟基频辐射的峰值和准峰值远远小于优化前的值，使产品顺利通过CISPR22 Class B测试，并使该产品顺利、及时地上市.

Simulation on and structure optimization on electromagnetic radiation of graphics card heatsink

As to the problem that the graphics card heatsink becomes larger and larger and its Electromagnetic Interference(EMI) easily exceeds the standard, the heatsink model of a graphics card is built by ANSYS HFSS and the effect of grounding mode on its radiation is analyzed; the parasitic parameters between heatsink and PCB are calculated and the heatsink shape is optimized to change the radiation pattern, which reduces the electromagnetic radiation efficiently. The test results in shield chamber indicate that the peak value and quasi peak value after optimization are far lower than that before optimization, which makes the product successfully pass the CISPR22 Class B test, and the product is marketed smoothly and timely.