接地技术最早是应用在强电系统（电力系统、输变电设备、电气设备）中，为了设备和人身的安全，将接地线直接接在大地上。由于大地的电容非常大，一般情况下可以将大地的电位视为零电位。后来，接地技术延伸应用到弱电系统中。对于电力电子设备将接地线直接接在大地上或者接在一个作为参考电位的导体上，当电流通过该参考电位时，不应产生电压降。然而由于不合理的接地，反而会引入了电磁干扰，比如共地线干扰、地环路干扰等，从而导致电力电子设备工作不正常。可见，接地技术是电力电子设备电磁兼容技术的重要内容之一，有必要对接地技术进行详细探讨。-Grounding technology was first applied in strong electric system (power system, power transmission equipment, electrical equipment), in order to equipment and personal safety, the ground wire directly connected to the earth. Because the earth capacitance is very large, under normal circumstances can be considered to be zero potential earth potential. Later, grounding techniques applied to extend the weak system. For power electronic devices directly connected to the ground wire on the ground or connected to a reference potential as a conductor, when the current through the reference potential, and should not generate voltage drop. However, due to unreasonable ground, but will the introduction of electromagnetic interference, such as co-ground interference, ground loop interference, resulting in power electronic equipment is not working properly. Visible, grounding technology is an important part of power electronic equipment EMC technology, it is necessary for grounding techniques disc