真空触发开关的触发能量和延时特性分析

本文采用辅助高压击穿与能量续流的触发电路来导通真空触发开关TVS，对触发过程中的触发能量和时延特性进行了分析和研究。结果表明，触发能量充足（〉20J）该电路稳定可靠地导通TVS；导通总延时在数百纳秒，并且随主间隙外加电压的增加有明显减小的趋势。     

闪光灯触发电路的有关问题

闪光灯触发电路的有关问题北京银燕电子闪光灯有限公司技术工程部“谈谈闪光灯的高压与低压触发”一文发表后，有朋友来信称受益非浅，也有朋友提出异议，认为闪光灯触发回路中不会有那么大的电流（５０Ａ）。对闪光灯电路不太清楚的同志，很容易产生上面误解。因此，首先...     

基于金属蒸汽沉积影响的真空触发开关的工作性能研究

真空触发开关(triggered vacuum switch,TVS)结合了三电极火花隙技术,以真空为灭弧和绝缘介质,具有通流能力强、体积小、控制简单、环境噪声小等优点。然而上百k A的脉冲电流所产生的真空电弧对TVS工作性能的影响不可避免,特别是基于沿面击穿产生初始等离子体的触发极。本文分析了影响TVS工作性能的多种因素,包括触发电压电流、主间隙金属蒸汽沉积以及超大电流真空电弧的烧蚀,认为金属蒸汽沉积是影响额定工况下TVS性能的主要因素,同时提出此影响下TVS触发电压、触发时延等性能参数的变化趋势。     

真空触发开关的起弧稳定性分析

真空触发开关(triggered vacuum switch,TVS)是大功率脉冲技术领域的重要开关器件之一,它具有结构紧凑、介质恢复迅速、操作无噪声、工作可靠性高、环境适应性强等优点,在中压领域具有广泛的应用前景.TVS的开通过程本质上是电弧燃烧过程.针对TVS的起弧稳定性,搭建了一套场击穿型TVS的触发和实验系统,从电气特性和图像特性两个方面记录其起弧过程.实验和理论分析表明,触发系统的稳定延时大约40μs,起弧过程持续297μs左右;初始等离子体的不同发展决定着TVS的开通.只有充足的初始等离子体,才能产生一定的鞘层电压,从而不断产生新的阴极斑点,保障起弧的稳定性.     

一种小型真空弧离子源的触发放电结构优化研究

在对一种小型触发型真空弧离子源的研究过程中发现,稳定的触发过程对真空弧离子源的主弧形成以及后续离子引出过程是至关重要的.传统触发结构为简单的触发极、绝缘体和阴极堆叠而成的"三明治"结构,触发过程为绝缘体表面的沿面放电过程,该结构若要实现稳定的触发需要很苛刻的外加条件.优化触发结构可有效提高离子源工作稳定性,降低电源要求...     

基于单片机AT89S52的晶闸管触发电路设计

该文阐述了基于单片机AT89S52构成的三相半波可控整流电路晶闸管触发电路的设计，介绍了AT89S52单片机控制的触发装置的硬件与软件设计，并且成功地改造了KGT-1型晶闸管调速装置。     

交直流电压条件下TVS触发特性研究

通过试验得到了触发系统的触发能量、触发电压与真空触发开关(TVS)导通概率、触发时延及分散性的关系,试验结果可以作为高性能真空触发开关控制器的设计与应用的指导。触发点火回路采用陡化高压触发脉冲,使TVS的导通时延及其分散性显著降低。引入同步触发技术,控制TVS主间隙在交流外施电压峰值触发。重点比较主间隙施加交直流情况下的触发特性,在触发参数、交流电压峰值与直流电压值相等的条件下,直流情况下TVS的导通概率和触发稳定性明显高于交流情况,交流情况下对触发系统的要求更为苛刻。     

高频逆变真空电弧蒸发电源

高频逆变真空电弧蒸发电源是现代电力电子技术与微电子技术的综合产物，因其具有高效节能、形小体轻、真空电弧稳定等特点，势必发展成为新一代电弧蒸发电源。本文就其主要工作原理、设计计算、实验数据等进行了分析研讨，并举电路实例供参照     

边沿触发超长时间定时电路设计思路

一般单稳态电路的暂态输出时间相对不是很长，而且电路的输入触发信号时间长度应小于暂态输出时间的长度，这种单稳态电路有时可能满足不了某些场合的实际工程需要。为此，本文给出了一种类似于单稳态触发电路但其输入触发信号的时间长度既可小于也可大于电路暂态输出时间长度，并且暂态的输出时间具有超长时间的定时电路设计方案。     

电脑型可控硅焊机软件触发技术研究

本文对电脑型可控硅焊机的软件触发技术进行了深入的研究。提出了利用 CTC 的一个通道进行重复定时的定时方式,这种定时方式具有硬件电路简单,动态响应灵敏度高的特点。采取软件触发后,使焊机的调试工作及触发电路大为简化。这种软件触发技术不仅可以应用在电脑型可控硅焊机上,也可以应用到其它微机控制的可控硅整流电路中。     

磁过滤阴极真空弧沉积装置研究中的等效电路方法

提出了模拟磁过滤阴极真空弧放电等离子体沉积装置阴极弧放电过程的等效电路 ,并用此电路定性研究了各参数对弧放电的影响 ,结果同实验符合的很好     

DC vacuum arc in a nonuniform axisymmetric magnetic field

An experimental investigation is performed of the characteristics of DC vacuum arc during the opening of contacts in an axisymmetric magnetic field with different ratios between the axial and radial components of magnetic field induction. A study is made of the main features of the dynamics of plasma glow in the contact gap during the stable and unstable stages of arcing until the arc extinction in the current range of 50 to 150 A with the voltage limited at the instant of breaking of current to a level of 8 kV. Possible mechanisms of disturbance of the vacuum arc stability in an axisymmetric magnetic field are discussed.     

Preparation and Arc Breakdown Behavior of Nanocrystalline W-Cu Electrical Contact Materials

1. IntroductionBecause of high strength and high conductivity cou-pled with low thermal expansion coefficient, W-Cu alloyshave been widely used in the field of power engineer-ing and plasma technology, such as contact materials formedium and high voltage interrupters as well as weld-ing electrode[1,2]. Usually, W-Cu alloys are produced bypowder metallurgy, but this technology often results inthe segregation of copper phase that will influence elec-trical properties of the contact material. I…     

A study into statistical regularities of extinction of a DC electric arc in an axisymmetric magnetic field

A statistical investigation is performed of the extinction of a 30–350 A electric arc in a vacuum gap, in which permanent magnets are used to generate an axisymmetric magnetic field with different ratios between the radial and axial components of magnetic field induction. Dependences are given of the duration of stable arcing and limiting interruption currents on the magnetic field induction and on the size of contact gap.     

A method of measuring electrode temperature for arc powercalculation

A technique for the construction of the thermocouple probe used for the measurement of electrode temperature under the influence of arcing in a low-power circuit breaker at break is reported. The problem of appreciable heat diffusion to the surroundings during the short time of arcing at break, typically 3-6 ms (depending on the speed of break), is dealt with by placing the thermocouple probe as near as possible to the electrode's surface, and in the center where, in most cases, the arc occurs. Under dc test conditions the amounts of the are power received by each electrode for various parameters such as current and electrode spacing are calculated     

脉冲真空弧离子源的质谱分析

本文介绍了脉冲真空弧离子源的特点,建立了脉冲真空弧离子源工作瞬间放气成分的质谱分析系统.应用四极质谱仪记录了真空系统中离子源工作前后的谱图,并通过数据软件的二次处理初步取得了脉冲真空弧离子源放电空间的增量成分分析;开展了不同绝缘介质对脉冲真空弧离子源工作瞬间所产生气体成分的对比研究.     

真空电渣重熔的冶金特性

真空电渣重熔具有脱氧性能好,防止金属氧化等许多优异的冶金特性.本文通过对真空电渣重熔与普通电渣重熔、气体保护熔炼和真空电弧熔炼等冶金特性的分析对比,找出真空电渣重熔的冶金特性,表明发展真空电渣重熔的意义.     

真空断路器绝缘子性能研究及结构改进

真空断路器的支撑绝缘子是传动机构的重要部件,起绝缘和支撑的作用。真空断路器的特性试验表明绝缘子断裂主要影响其中“弹跳时间”和“不同期时间”两项试验,即对断路器的使用有直接影响,特别是满足不了其电气性能上的要求。环氧树脂绝缘子在使用过程中发生断裂的几率很小,但由于绝缘子失效对真空断路器的综合使用性能影响很大,所以结合真空断路器操动机构对支撑绝缘子性能进行分析研究,具有现实价值。     

Dielectric characteristics of vacuum circuit breakers with CuCr and CuBi contacts before and after short-circuit breaking operations

This paper presents the results of the degree of irreversible changes of dielectric properties of vacuum circuit breakers with CuCr and CuBi contacts before and after short-circuit breaking operations. Tests of dielectric properties were performed on four different types of switching vacuum chamber with RMF electrodes in the form of a spiral disk with slots. The paper describes the configuration of measuring system for determining the dielectric properties of circuit breakers with DC, AC and pulse voltage. It also describes the measuring procedure. The results were analyzed and the experimentally obtained random variable breakdown voltage is found to belong to Weibull distribution in all cases. Based on these results it was found that for the vacuum circuit breakers with CuCr contacts and CuBi breakdown occurs by the emission mechanism after stopping of diffuse arc with the initial breakdown at the anode. It was also found that significant reduction of the breakdown voltage occurs only after a short-circuit current breaking for a constricted arc. Only in this case, the significant difference between circuit breakers with CuBi and CuCr contacts is observed. This difference is explained by the fact that breakdown voltage for a constricted arc strongly depends on the shape of the applied voltage by the action mechanism of micro particles generated during the breaking of the arc current for the vacuum circuit breakers with CuBi contacts and it is caused by material of contacts. The results confirm the lower degree of irreversible changes of dielectric properties of vacuum circuit breakers with CuCr contacts in operation.     

6063铝材微弧氧化最佳电流密度和槽液温度的探讨

目前的铝合金微弧氧化工艺存在电流密度高、槽液温度范围窄等不足,使其应用受到了限制.为此,从铝材低电流密度和宽槽液温度方面研究了6063铝材的微弧氧化工艺,探讨了微弧氧化工艺中电流密度及槽液温度对起弧电压、起弧时间及膜层厚度等的影响.结果表明,同等条件下,电流密度越大,则起弧电压越低,起弧时间越短,膜层越厚;槽液温度越高,则起弧电压越低,起弧时间越短,膜层越厚;在10 min内,得到12μm厚度的膜层,同等时间内比普通阳极氧化膜厚提高4倍;微弧氧化膜的表面显微硬度相对6063铝材高7倍以上.