对空气式静电放电的研究

Study on Air-type Electrostatic Discharge

为改善空气放电模拟方法，用静电放电模拟测试装置研究了IEC标准规定的空气式静电放电的放电特性。通过手动方式使充电后的放电电极快速靠近电流靶获得空气静电放电事件，放电电压具有2～20kV较宽范围的电压电平和正负电压极性。利用Agilent数字存储示波器测量了空气静电放电放电电流的上升时间、峰值以及耦合到自制的金属半圆环上的峰-峰值电压，并记录了放电电流和耦合电压的波形。通过分析和比较测量结果研究了测量参数随放电电平的变化趋势。空气放电电流的特性与静电放电抗扰度试验标准IEC61000-4-2对接触式放电的规定类似，耦合电压与放电电压之间没有直接的相关性。实验表明在一定电压范围、电极速度可控时可能获得空气放电的重复性。

The investigation for the discharge characteristics of air-type electrostatic discharge （ESD） specialized in IEC standard is performed on the simple self-designed ESD simulation and ESD test set-up. The air electrostatic discharge events are obtained by moving the charged discharge tip to the current target with high speed by hand during the testing. The discharge voltages have broad range from 2 kV to 30kV, and have both positive and negative polarities. Using an advanced Agilent digital memory oscilloscope, the rise-times and the peak amplitudes of air electrostatic discharge current and peak-peak voltages induced on the self-made semi-metal-loop are measured, and the waveforms of the discharge current and induced-voltage are recorded. The measured results are analyzed and compared, and the change trends of the measured parameters with different voltage levels are discussed. The discharge characteristics of air electrostatic discharge are similar with the discharge characteristics of contact electrostatics specialized in the electrostatic discharge immunity test standard IEC 61000-4-2. There is no direct correlation between the induced voltages and the discharge voltages. It is shown that it is possible to achieve the repeatability of air electrostatic discharge if the approach speed of discharge tip can be controlled at a special range of voltage level.