空气湿度对Zn-Al复合膜的影响与决策

叙述了金属化膜的发展历史 ,分析了湿度对 Zn- Al膜的影响 ,提出了减少水份吸附的对策和防止金属化膜氧化的三种方法。在生产过程中 ,采取有效的防潮措施 ,是关键工艺之一。Zn- Al复合是一种自愈性能优异的金属化膜 ,只要采取适当的工艺措施 ,就能生产出性能很好的电容器     

空气湿度对Zn-Al复合膜的影响与决策

叙述了金属化膜的发展历史 ,分析了湿度对 Zn- Al膜的影响 ,提出了减少水份吸附的对策和防止金属化膜氧化的三种方法。在生产过程中 ,采取有效的防潮措施 ,是关键工艺之一。Zn- Al复合是一种自愈性能优异的金属化膜 ,只要采取适当的工艺措施 ,就能生产出性能很好的电容器     

金属化膜脉冲电容器寿命测试方法

金属化膜脉冲电容器在脉冲功率装置中得到广泛的应用.当电容器内部出现短暂的薄膜击穿现象时电容器因自愈性能而恢复绝缘,使得电容器的稳定性得到提高.但由于自愈的不断进行,电容量不断减少.金属化膜脉冲电容器以5％的电容量下降作为寿命终结的标志.本文对影响金属化膜脉冲电容器寿命的因素进行了分析,提出了按不同影响因素测试金属化膜脉冲电容器寿命特性的方法,并对此测试方法的原理与主要设备进行了说明.此方法可高效测试金属化膜脉冲电容器的寿命特性,对获取电容器寿命特性以及基于寿命测试而形成寿命预测具有一定的指导意义.     

金属化膜脉冲电容器寿命测试方法

金属化膜脉冲电容器在脉冲功率装置中得到广泛的应用。当电容器内部出现短暂的薄膜击穿现象时电容器因自愈性能而恢复绝缘,使得电容器的稳定性得到提高。但由于自愈的不断进行,电容量不断减少。金属化膜脉冲电容器以5%的电容量下降作为寿命终结的标志。本文对影响金属化膜脉冲电容器寿命的因素进行了分析,提出了按不同影响因素测试金属化膜脉冲电容器寿命特性的方法,并对此测试方法的原理与主要设备进行了说明。此方法可高效测试金属化膜脉冲电容器的寿命特性,对获取电容器寿命特性以及基于寿命测试而形成寿命预测具有一定的指导意义。     

交直流复合电压下温度和膜厚对金属化膜击穿特性影响研究

本文对不同温度和不同膜厚条件下的交直流电场叠加下的金属化膜的击穿特性进行了试验研究,试验结果表明,金属化膜的击穿强度随着温度的升高和膜厚的增加而下降。因此本文建议在金属化膜电容器设计过程中采用一定优化元件的排列方式以加强散热,在其运行过程中要采取一定的冷却方法来降低金属化膜电容器的温度以提高电容器的绝缘性能,在选择电容器膜厚的时候可以根据其所处的电压等级进行选择并根据实际条件综合考虑。本文的研究成果能够给金属化膜电容器的绝缘性能设计以及工作性能的优化提供参考。     

金属化膜电容器层间压强计算

金属化膜电容器的优点是储能密度高、可靠性高及成本低,其自愈特性和端部通流能力与层间压强有关。笔者用理论方法计算了层间压强,并根据液体表面产生附加压强原理,分析和计算了金属化膜电容器热处理前后层间压强的变化。计算结果表明,电容器的层间压强是由里向外是递减的,经热处理后的压强是热处理前压强的3倍以上。     

锌铝金属化膜氧化腐蚀及其防护

1　前言金属化薄膜是制造各类金属化薄膜电容器的重要介质材料。根据金属化极板所用材料不同,有锌(Zn)金属化膜、铝(Al)金属化膜、锌铝(Zn-Al)金属化膜、银锌铝(Ag-Zn-Al)金属化膜等。由于Zn金属化膜极易氧化,不便贮存和运输,其应用范围受到限制。而Al金属化膜由于其优良的抗氧化性能,便于贮存和运输等特点,从而得到广泛的应用。近几年随着电子整机产品对元器件要求越来越高,Al金属化电容器的耐压强度低,容量衰减大,损耗增加量大的缺点日益显露出来。而同期开发的Al-Zn复合金属膜则显著提高了电容器的耐压性能,大大减少了电容器的容量…     

金属化膜和金属化T型安全膜在直流支撑电容器中的对比试验研究

通过对同一基膜,采用均匀蒸镀和T型蒸镀的金属化膜制作的元件进行各项性能对比试验研究,研究两种金属化膜的性能及差异;通过直流支撑电容器进行产品性能更深入的研究,验证国产金属化膜直流支撑电容器综合技术水平,促进柔性直流输电工程用直流支撑电容器及主要材料的国产化发展。     

高场强下金属化膜脉冲电容器特性的试验研究

介绍了金属化膜电容器的工作原理 ,研究了金属化膜脉冲电容器与箔式电容器工作特性的差别。并结合金属化膜电容器试品的解剖分析结果 ,对在高场强下金属化膜脉冲电容器的试验特性进行了分析与探讨     

金属化电容器元件端头接触电阻及监测方法

前言目前我国低压并联电容器正处于更新换代时期,采用国际上七十年代的金属化聚丙烯膜电容器代替四十年代的油浸纸电容器的工作已在开展。金属化电容器的各项电性能及比特性均大大优越于油浸纸介电容器。但是金属化电容器的工艺比较复杂,特别是元件端头的接触电阻对产品质量影响尤为严重。本文试图就控制元件端头接触电阻进行初步探讨。     

提高金属化薄膜电容器的脉冲电流处理能力

喷金是金属化薄膜电容器生产过程中的重要关键工艺,喷金质量的好坏直接影响着电容器的性能和寿命。基于喷金机的工作原理,对喷金距离、喷金颗粒、压缩空气等方面进行研究,并给出了提高喷金质量的方法。最后通过实验和批量生产来验证了这一改善的效果,事实证明工艺改进确实大大提高了薄膜电容器的脉冲电流处理能力,同时还节约了喷金料,降低了生产成本。     

Numerically established correlation in electrical responses ofpolymer film capacitors to ac and pulsed voltages

In this paper, an equivalent circuit model is used to simulate electrical responses of metalized polymer film capacitors to either ac voltage or pulsed voltage stresses, in particular electric field induced on the electrode coating surface and power dissipation within the film capacitor. Electrode segmentation patterns are taken into consideration by means of arrays of interconnected lumped surface resistors, and the film capacitance is modeled by a set of shunt capacitors distributed across the length of the capacitor film. Voltage magnitude and waveform characteristics are studied in great detail for their effects on surface electric field and power dissipation. Through numerical examples, surface electric field and dissipated power induced by one type of external stress (ac or pulsed) at one frequency are shown to correlate with those at a different frequency. Further correlation is also established to relate surface field and dissipated power induced by one type stress (e.g. ac) to those by the other (pulsed), provided the waveform. characteristics of the two different stresses are specifically related. These numerically established correlations can permit significant reduction in development time of metalized film capacitors     

应用于DC-Link电容器的金属化膜自愈特性分析

金属化DC-Link电容器较传统电解电容器具有很多优势,如何减少金属化膜电容器在自愈过程中的电容量衰减是一个重要研究课题。文章分析了金属化电容器自愈特性,研究了自愈特性与压强关系,通过自愈特性试验,结果表明压强的增大可减少自愈能量、优化自愈性能、减少自愈面积,对提升DC-Link电容器的性能具有指导意义。     

提高金属化薄膜电容器的脉冲电流处理能力

喷金是金属化薄膜电容器生产过程中的重要关键工艺，喷金质量的好坏直接影响着电容器的性能和寿命。基于喷金机的工作原理，对喷金距离、喷金颗粒、压缩空气等方面进行研究，并给出了提高喷金质量的方法。最后通过实验和批量生产来验证了这一改善的效果，事实证明工艺改进确实大大提高了薄膜电容器的脉冲电流处理能力，同时还节约了喷金料，降低了生产成本。     

电力电子装置滤波电容容量的设计方法

由于工作在高频电力电子装置中的滤波电容等效容量会随着工作频率的增加而减小,而由滤波电容的等效电阻和纹波电流产生的发热量会随之增加。因此,合理选择高频电力电子装置的滤波电容容量是电力电子装置设计的一个必要环节。提出了根据纹波电流大小设计电力电子装置的滤波电容容量的一般方法,针对滤波电容中纹波电流与开关频率的关系,纹波电流与电容发热量的关系以及纹波电流对电容器寿命的影响,给出了详细的计算公式。这种滤波电容容量的选择方法对于通用变频器、大功率开关电源等应用场合具有一定的实用参考价值。     

Improvement in the electrical properties of ferroelectric SrBi2Ta2O9 capacitors by electron beam irradiation on precursor films

Abstract

Ferroelectric SrBi₂Ta₂O₉ (SBT) capacitors were fabricated by the Electron-Beam-Induced Patterning process and their electrical properties were evaluated in detail. In this process, the dose of an electron beam irradiated on precursor films had a great influence on the electrical properties of the SBT capacitors. The appropriate electron dose significantly improved the electrical properties of the SBT capacitors although the excess electron dose made severe deterioration in the properties. The SBT capacitors fabricated with the optimum electron dose, 1.5 mC/cm² for Sr:Bi:Ta = 0.8:2.2:2.0 solutions, exhibited excellent ferroelectric properties: a remanent polarization of 11.5 μC/cm², a coercive field of 40 kV/cm, a leakage current of 8×10^?8 A/cm²@ 1V and fatigue-free up to 1010 cycles. It seems that such improvements were caused by the adjustment of Bi contents in the films and the modification or the decompositon of precursors before heat treatment by electron beam irradiation.     

高压脉冲电容器的直流局部放电绝缘检测

高压脉冲电容器的绝缘性能直接关系到其在放电单元中工作的可靠性,直流局部放电测试能够为评估高压脉冲电容器绝缘性能状况提供有效信息。在分析油浸膜—纸绝缘电容器的绝缘特性的基础上,利用所研制的直流局部放电测试系统在一般屏蔽实验室条件下应用平衡法对油浸膜—纸绝缘电容器进行了直流局部放电实验研究,结果表明,可以用放电量—局部放电次数来表征电容器的绝缘状况。通过一批同型号、同批次电容器的直流局部放电试验研究,证明电容器绝缘劣化严重时,其局部放电水平随电压增加而剧烈变化。     

The fundamentals of aging in HV polymer-film capacitors

This paper covers the basic phenomena involved in the aging of capacitors constructed using polymer films as the major dielectric material. A wide variety of aging phenomena can be identified, ranging from simple electrical, dielectric, thermal, radiation, chemical and physical aging, to aging originating from the specific construction of the capacitor. Some phenomena occur quickly, such as some morphological changes in the polymer, others occur progressively, and others occur later in the life of the capacitor. The polymers covered range from biaxially-oriented polypropylene, which is widely used in commercial utility and industrial capacitors, to polymers like polycarbonate, polysulfone, polyimide, and polyvinylidene fluoride, which are used in high-energy density, outer-space, high-temperature, or other special applications. The paper addresses two constructions of polymer film capacitor where the aging phenomena are significantly different due to the differences in construction: polymer/foil capacitors and metalized film capacitors. Metalized polymer film capacitors have the quality of clearing or self healing that is not present in film/foil capacitors. The discussion of aging in this paper is given from the perspective of these two designs     

Dielectric properties, of metallized paper-film capacitors

A capacitor formed of fluid-impregnated paper metalized on one side and a polymer film results in a relaxation peak caused by the much more rapid polarization of the dielectric fluid impregnated paper relative to the polymer film. This results in the capacitance being a function of frequency, with a substantial increase in capacitance at very low frequencies. A theory for such a capacitor is developed and compared with measurements on actual capacitors with relatively good agreement. The implications of the theory for discharge current and discharge efficiency are discussed.