传导发射测试是红外成像系统必须通过的一项电磁兼容性测试。在研制阶段进行实验室内部的诊断性传导测试，将使得红外成像系统更容易满足电磁兼容标准要求，从而缩短了研发周期，提高了系统探测率。而漏电保护是红外成像系统实验室做传导测试所面临的首要问题。分析了红外成像系统实验室中传导测试使用LISN 引起漏电保护的原因，并针对红外成像系统的特点提出了两种新的LISN设计方案，并在仿真中验证了设计的合理性，解决了红外成像系统实验室中做诊断性的传导测量引起的漏电保护问题。

Electromagnetic compatibility test on conducted emissions is necessary for IR imaging system. In design stage of IR imaging system，doing laboratorial diagnostic conducted emissions test can make the lab design satisfy the requirement of EMC standards，thus can shorten the period of design and improve the system detectivity. The most important issue of the conducted emissions test is the leakage protection. The reason of leakage protection in conducted emissions test is discussed in this paper firstly. And then two new designs are proposed to avoid leakage protection. At last the better design is verified with computer simulation.