Computational estimation of ESD conditions between a charged bodyand a conductor of floating potential

This paper examines the conditions in which a discharge occurs between a charged body and a floating conductor, in air, at atmospheric pressure. The study, which was primarily aimed at simulating a class of hazardous situations quite often met in the operation of electronic circuits, is also of interest to those involved in the research and development of electrostatic technologies for processing of particulate matter: separation of granular mixtures, precipitation of dust, and spraying of powders. The boundary-element method was employed for the analysis of the electric field in the gap between the charged body and the conductive disk at floating potential, located above a grounded plate. The computations were carried out for bodies of various shapes and sizes; some of them addressed the case of a grounded plate covered with an insulating layer of known permittivity. The data on field distribution represented the input data of another program, which estimated the breakdown conditions of that air gap. The study enabled the estimation of the energy involved in this type of electrostatic discharge and the prediction of the related hazards     

Realizability conditions on short-circuit conductance matrix by means of grounded active resistive networks embedding grounded VCVSs

The proof is given of a new theorem concerning the minimum number of ideal grounded voltage-controlled voltage sources (VCVSs) necessary and sufficient to realize an arbitrary real square matrix as the short-circuit conductance matrix of a grounded transformerless active resistive multiport network embedding grounded VCVSs.     

ESD辐射场的计算及对传输线的耦合研究

为分析静电放电的辐射场及其对传输线与负载终端的影响,采用了一种基于脉冲函数的静电放电电流波形解析表达式计算了静电放电电磁脉冲辐射场并给出了近场和远场波形。结果表明放电电场包括由初始电荷引起的静电场和由放电电流引起的辐射场,在放电电极附近,静电场远大于辐射场,但静电场随空间距离衰减得很快,在远区场主要由放电电流引起的辐射场。利用传输线理论建立静电放电场对电长导线的耦合计算模型得出了静电放电辐射场在线上的感应电压和感应电流计算方程。     

TCAD Methodology for ESD Robustness Prediction of Smart Power ESD Devices

This paper presents a new method to predict the electrostatic-discharge (ESD) protection robustness of a device with technology-in-computer-aided-design (TCAD) simulations. Tested on different devices and two Smart Power technologies, the results are validated through electrical measurement and failure analysis. Failure current is always predicted with a good accuracy compared to technology spreading. In addition, the methodology provides a significant simulation time speedup compared to classical methods based on a temperature criterion     

Leakage current characterization for estimating the conditions of ceramic and polymeric insulating surfaces

Leakage current produced on contaminated ceramic and polymeric insulating surfaces was analyzed using a wavelet transform technique providing time-frequency domain information. Salt-fog tests with and without the deposition of non-soluble contamination were conducted in a laboratory, during which the leakage current was separated into sinusoidal, local arc, or their transition components per halfwave of power frequency. The wavelet transform allowed the detection of the zero-cross point of the base current at 50 Hz without the need for voltage information. The source information regarding the distortion level (I/sub 150 Hz//I/sub 50 Hz/) of the current half-wave separated by the zero-cross point and a time lag to onset in current attributable to arcs are used in order to obtain the above three components. The time-integrated values (cumulative charges) of these components were found to correlate with hydrophobicity and contamination level. It was shown that time variations of the cumulative charges and of their component ratios were useful for estimating the conditions of ceramic and polymeric insulating surfaces.     

ESD engineering of nitride-based LEDs

GaN-based light emitting diodes (LEDs) with p-cap layers grown at various temperatures were fabricated. It was found that the LED with 900/spl deg/C-grown p-cap layer could only endure negative 1100 V electrostatic discharge (ESD) pulses while the LED with 1040/spl deg/C-grown p-cap layer could endure ESD pulses as high as negative 3500 V. It was also found that the ESD performances of the LEDs with 900 and 1040/spl deg/C-grown p-cap layers were limited by the V-shape defects and the bonding pad design, respectively.     

电力系统中直流接地电阻检测和接地故障点探测的方法研究

本文论述了现有的直流系统接地故障检测方法及其不足之处,提出了一种全新的直流接地故障检测方法。该方法具有对直流系统无任何不良影响;检测结果不受分布电容的影响,检测精度高;能准确判断故障所在支路,故障定点准确;电路简单,成本低廉等优点。     

Leakage current characterization for estimating the conditions of non-ceramic insulators’ surfaces

In this work both detection of the beginning of dry-band arcing and correlating the average value of leakage current (LC) with non-ceramic insulator surface damage have been investigated. Silicone rubber insulators were tested in salt-fog under different voltage and conductivity levels. The autocorrelation function (ACF) was calculated for both the fundamental and third harmonic components of LC during the early aging period (EAP). It has been observed that distinct differences exist in the behavior of both the fundamental and that of the third harmonic components of the LC during EAP. Although the fundamental component of the LC begins to grow immediately after starting the test, the third harmonic requires a much longer period of time to begin. Dry-band arcing is highly correlated with distortion in the LC and hence to its third harmonic component. But it has been observed that the level of the fundamental component of LC at which the third harmonic component started to increase is different from one case to another. As such, it is more appropriate to use the ACF of the third harmonic component of LC as an indication of dry-band arcing rather than a simple threshold value. Moreover, the average value of LC during late aging period (LAP) was correlated with the damage of non-ceramic insulators. It has been found that the average level of both the fundamental and third harmonic component of LC is well correlated with the different degrees of damage of non-ceramic insulators’ surface.     

动态工况电池在线参数辨识及SOC估计研究

基于电池模型的荷电状态(SOC)估计方法,其估计精度主要取决于模型的精度。电池在动态工况下,输入电流变化激烈,传统的辨识方法因其收敛性差,导致模型精度降低。为了提高动态工况下电池模型精度,对传统带遗忘因子最小二乘法(FFRLS)进行改进,通过设置精度阈值,引入梯度矫正的方法,提出了改进带遗忘因子递推最小二乘法(IFFRLS)。利用改进算法进行在线参数辨识,建立二阶RC等效电路模型,与其他传统参数辨识建立的模型进行对比,验证IFFRLS对模型精度提高的有效性,模型平均误差为0.003 8 V。最后,将不同辨识方法所建立的模型与扩展卡尔曼滤波(EKF)算法进行联合估计SOC并对比其误差,结果表明通过IFFRLS辨识出来的高精度模型可有效提高SOC的估计精度,DST工况下,误差在1.51%以内。     

动态工况电池在线参数辨识及SOC估计研究

基于电池模型的荷电状态(SOC)估计方法,其估计精度主要取决于模型的精度。电池在动态工况下,输入电流变化激烈,传统的辨识方法因其收敛性差,导致模型精度降低。为了提高动态工况下电池模型精度,对传统带遗忘因子最小二乘法(FFRLS)进行改进,通过设置精度阈值,引入梯度矫正的方法,提出了改进带遗忘因子递推最小二乘法(IFFRLS)。利用改进算法进行在线参数辨识,建立二阶RC等效电路模型,与其他传统参数辨识建立的模型进行对比,验证IFFRLS对模型精度提高的有效性,模型平均误差为0.003 8 V。最后,将不同辨识方法所建立的模型与扩展卡尔曼滤波(EKF)算法进行联合估计SOC并对比其误差,结果表明通过IFFRLS辨识出来的高精度模型可有效提高SOC的估计精度,DST工况下,误差在1.51%以内。     

ESD发生器开关动作对抗扰度试验的影响

分析了人体-金属静电放电(ESD)发生器开关动作的基本过程;说明了在ESD抗扰度试验中ESD发生器开关动作的影响。通过空气放电模拟测试装置测量并记录了ESS-200 AX、SANKI NS61000-2A和NSG-435 3种ESD发生器开关动作的影响。由小环耦合电压的测量研究了ESD发生器开关动作产生的辐射场。结果表明,使用不同的ESD发生器开关动作的影响程度不一样,且使用相同的ESD发生器开关闭合和开关释放的影响存在差异。对小环耦合电压的频谱分析表明,开关动作会产生频谱范围较宽的电磁骚扰,影响对高速逻辑器件的ESD抗扰度试验。在进行ESD抗扰度试验时,需考虑ESD辐射场,尤其需要降低或控制ESD发生器开关动作产生的辐射场。     

ESD电流的解析表达式与数值解

分析IEC6100042静电放电(ESD)电流波形典型拟合解析表达式表明,这种由有限点拟合曲线的纯数学方式存在拟合的多样性,无可依据的物理基础。因而根据ESD物理特性提出了一种通过数值计算等效电路模型获得ESD电流数值解的方法,由该方法算出的电流峰值、上升时间、i30ns、i60ns等关键参数与IEC610042电流波形参数的相对误差的最大值均<1.6‰,为ESD辐射电磁场研究提供了有效的手段。     

智能电网电力集中器静电放电抗扰度机理及防护方法

针对智能电网中电力集中器等电子设备产生的静电放电(ESD)抗扰度问题,分别利用电路理论和Wilson偶极子模型分析了静电感应产生的高电压、大电流以及辐射电磁场,建立了非金属绝缘外壳系统、无接地系统和敏感器件模型.提出了基于ESD地和电磁屏蔽的静电放电防护方法,即通过ESD地与大地之间的分布电容泄放高电压、大电流,利用E...     

静电放电试验中示波器的选择与使用

介绍了数字示波器测量带宽及采样速率方面的有关知识,分析了示波器对静电放电试验中上升时间测量的影响,提出了解决的具体措施,对其它领域快速非重复信号的测量有一定的指导意义。     

集成电路静电放电模拟器校准与测量不确定度

集成电路静电放电模拟器是微电子元器件可靠性筛选的重要设备,通过模拟静电放电对器件的抗静电能力进行筛选.本文在分析静电放电模拟器工作原理的基础上,利用高频电流探头和高速率采样示波器实现了对模拟器的校准.文章还并结合校准实例,对测量不确定度进行了评定.     

Wavelet transforms for real-time estimation of transmission line impedance under transient conditions

 Waveforms of voltages and currents in electrical power systems may include higher harmonics, transient components and random noise. For control and protection devices, it is necessary to estimate parameters of the basic waveform. The most well-known methods are based on the Fourier technique. The estimated phasors of the basic component can be applied to the calculation of the impedance of a faulty transmission line. In this paper, the current and voltage phasors were estimated using complex wavelets. The filter properties of the wavelet approach are better than those of the Fourier. Received: 20 July 2001/Accepted: 10 August 2001     

静电放电电流的频谱分析与计算

从静电放电的人体模型入手 ,从理论上详细分析并计算了更具实际意义的人体 -金属模型静电放电电流的频谱 ,解决了电磁兼容 (EMC)测试中注入信号的特性问题。计算结果表明静电放电的高频能量相对较少 ,存在一有效带宽。静电放电电流的准确测试系统应有超宽频带和近百 d B的动态测定范围     

乙苯装置ESD系统的设计与实现

ESD系统是大型流程工业生产装置的自动保护系统。它可以防止由于生产工艺故障或其他一些事故对工艺设备、生产系统、操作人员的损害,保证生产能够安全地运行,本文结合兰州石化公司合成橡胶厂对乙苯装置联锁系统ESD的研究与设计,介绍了ESD系统的结构和实现。