智能电器监控单元静电放电敏感性的实验研究

为研究智能电器监控单元的静电放电敏感性,利用静电放电发生器对设备机壳放电进行了实验研究。根据静电放电干扰的耦合途径以及智能电器监控单元的实际工作情况,选取电源模块直流侧电压作为研究智能电器监控单元的静电放电敏感性的对象,通过频谱分析得出直流侧对地电压和静电放电电压间的关系。装置采取屏蔽、接地和滤波等抗干扰措施时其静电放电敏感性降低,分析直流侧电压发生的相应变化得出结论:静电放电时,智能电器监控单元直流侧对地电压与装置的静电放电敏感性有一定的相关性。

Experimental Studies on the Susceptibility to Electrostatic Discharge of Digital Relay

The electrostatic susceptibility of digital relay was experimentally studied through discharging to the shell by the electrostatic discharge (ESD) generator. On the basis of deeply analyzing the coupling path of interference caused by ESD and operation state of digital relay, the voltage of direct current (DC) side of power supply module of digital relay was selected as the object to research the susceptibility to electrostatic discharge, the relation between the voltage of DC side of power supply module and ESD voltage was founded by spectrum analyzing. From integral tendency, it could be seen that the voltage of DC side of power supply module increased as the discharge voltage raising. When anti-interference methods, such as shield, grounding and filter waves, were adopted, the susceptibility to electrostatic discharge of equipment decreased and voltage of DC side changed accordingly. The following results were gotten by analyzing spectrum of the voltage of DC side: change occurred at the high frequency part of the spectrum of the voltage of DC side when the ESD gun zapping on the discontinous spot of shielding conductor, the spectrum of DC side was related to the characteristic of impedance of ground wire at various frequency bands, the characteristic of wave filter could influence the spectrum of the voltage of DC side. Spectrum analyzing result of the voltage of DC side is coordinated with suppression effectiveness of these anti-interference methods at various frequency bands. A piece of conclusion was obtained accordingly: voltage of DC side of power supply module of digital relay has some correlation with its electrostatic discharge susceptibility.