弱电系统中的地线干扰与接地方法

Grounding Wire Interference and Grounding Method in Electronic System

介绍了地线的干扰机理以及减小地线干扰的对策和接地的基本方法。在电子电路中 ,地线不仅为电路提供一个电位公共参考点 ,而且也为电流提供一条能够流回源的低阻抗路径。由于地线存在阻抗 ,当电流流过地线时 ,会在地线上产生电压差 ,从而形成地线干扰 ,严重时将会影响电路的正常工作。减小或消除地线干扰的主要方法是减小地线的阻抗和地线电流。为此 ,可以针对不同的信号频率及干扰性质 ,根据系统的结构和功能采用相应的接地方式 ,将接地。

In electronic circuits, the grounding wire offers not only a common voltage reference for the circuit, but also a low impedance line for currents which return to their source. Because the grounding wires have some impedance, there is a voltage drop on the grounding wire when the currents go through it. As a result it causes the grounding interferences. The circuits can't work properly (operate well) when the grounding interferences are large. So we must choose correct types of the grounding wires and grounded methods to reduce or eliminate the grounding noises.