SrTiO3陶瓷变阻器

SrTiO_3陶瓷变阻器是一种新型的复合功能元件,它既具有电容器功能,又具有吸收浪涌的压敏电阻器作用的功能。在工业电子设备、家用电子设备中均有广泛的应用,并可大大地提高电子设备的抗干扰性能和抗噪声能力。本文简要介绍了SrTiO_3陶瓷变阻器的制造方法和电气特性,以及它们在电器设备中的主要应用。     

氧化锌压敏电阻器的应用

氧化锌压敏电阻器的主要功能是探测和抑制反复出现的浪涌电压及过电压而自身不会破坏。具有优良的非线性伏安特性，在稳态工作电压下漏电流很小（能耗低）。利用这些特性可制造各种半导体器件的过电压保护、电子设备的雷击浪涌保护、各种负荷开关的浪涌吸收、各种装置中的瞬间脉冲抑制等电子保护装置。     

SrTiO_3环形压敏电阻器

以ＳｒＴｉＯ_３为主晶相，以Ｌａ_２Ｏ_３为施主杂质，在还原气氛下烧结使其充分半导化；掺杂多种金属氧化物，通过高温氧化处理形成晶界层，研制出环形压敏电阻器。其性能优于原有的ＺｎＯ环形压敏电阻器，不仅压敏特性优良，且具有很高的电容量，是一种双功能元件。更重要的是解决了ＺｎＯ压敏电阻器固有的在焊接挂锡后电压降低严重的问题。该成果填补了国内空白，并于１９９２年通过机电部设计定型鉴定。     

具有电容器和压敏电阻器双重功能的独石器件

国外已制成具有电容器和压敏电阻器双重功能的独石器件。其容量为1μF;在1～100kHz,损耗角正切小于0.05。在电压大于阈电压(V_0)约15V的情况下,器件传导电流I=AV~α;非线性指数α为11.4。该器件可用于电子设备的保护,以防止电压脉冲。适当的电容器和压敏电阻器的组成具有相同的烧结温度。可在900～1350℃烧结制成独石器件。     

ZnO压敏电阻器在电源电路中的应用及其展望

ＺｎＯ压敏电阻器是６０年代末期研制成功的新型过电压保护元件。本文就ＺｎＯ压敏电阻器的特性及其抑制过电压原理，分析了电源电路产生过电压的原因及其对策，得出用ＺｎＯ压敏电阻器抑制过电压是一种较为理想的方法，它具有保护效果好、可靠性高、节能、价廉等一系列优点。文中还就如何应用ＺｎＯ压敏电阻器来保护电源线路、变压器、半导体整流元件、电气电子机器和家电等，给出了保护电路、选用原则和使用注意事项。目前ＺｎＯ压敏电阻器已有成功地应用于某些电源电路的过电压保护的实例，并取得了明显的经济效益。可以预料，ＺｎＯ压敏电阻器将是电源设计者和使用者不可缺少的新型浪涌吸收元件，将广泛地应用于各类电源电路的保护。     

新型SrTIO3电磁兼容元件的特点及应用

本首先概括地说明了具有电容性、压敏性的ＳｒＴｉＯ３双功能电磁兼容元件的基本特点。把ＳｒＴｉＯ３双功能元件、ＺｎＯ压敏电阻器、普通陶瓷电容器掏陡脉冲干扰析性能进行了对比,显示出该元件具有优异的抗干扰性能。最后列举了ＳｒＴｉＯ３双功能元件的主要应用领域,说明该元件具有广阔的应用前景。     

片式叠层压敏电阻器及其应用

用流延工艺把电极层和半导体陶瓷交错排布，经烧结而成的片式叠层压敏电阻器，其结构类似多层陶瓷电容器。通过与氧化锌压敏电阻器及其他压敏电阻器比较表明，片式叠层压敏电阻器具有优良的性能。并论述这类压敏电阻器在ＩＣ保护、ＣＭＯＳ器件保护、汽车电路系统保护等方面的应用。     

SiO_2对ZnO压敏电阻器性能的影响

实验研究了ＳｉＯ２对ＺｎＯ压敏电阻器性能的影响，在ＺｎＯ陶瓷中，添加适量的ＳｉＯ２可以提高压敏电阻器的α值和电压梯度，降低漏泄电流，提高通流量，能够制造出性能优异的ＺｎＯ压敏电阻器。     

压敏电阻器的电阻值

压敏电阻器是一种限压型非线性电阻器,主要用于抑制浪涌过电压。通常不用电阻值而用电压(压敏电压、限制电压)或电流(漏电流、最大脉冲电流)来描述它的特性。但是,在有些问题中,例如在压敏电阻器的冲击电流试验中,要考虑它与冲击电流发生回路的匹配问题,这时用电阻值这个参数就更为方便。根据作者在研制压敏电阻器测试仪器中所进行的实验,对压敏电阻器的电阻值这个参数作一些讨论。     

优选组分,改进工艺,提高氧化锌压敏电阻器性能

氧化锌(ZnO)压敏电阻器,是以ZnO为基础,添加多种微量金属氧化物,采用电子陶瓷工艺制作而成的半导体陶瓷敏感元件,具有优异的非线性电流电压特性。自问世以来,已广泛地应用于电力设备和电子线路中,主要用作过电压保护和浪涌抑制等。在汽车工业,铁路信号和通讯设备中所使用的ZnO压敏电阻器,通常要求应具有较高的耐浪涌能力,目前,由于此类产品的市场需求量增大,引起了人们的极大关注,因此,制造非线性好,耐浪涌能力强的高能氧化锌压敏电阻器,就显得十分重要。     

ZnO压敏电阻两片并联方法及性能分析

目前,常采用将压敏电阻片( MOV)并联的方法来提高压敏型电涌保护器(SPD)的通流容量和电压保护水平.根据ZnO压敏电阻的伏安特性,利用冲击发生器HAEFELY PSURGE 30.2和CJ1001型压敏电阻直流参数仪进行了大规模实验,通过对实验数据进行对比分析发现,将压敏电压U1mA作为并联选片的参数是可行的;双片...     

$hbox{VO}_{2}$ Thin-Film Varistor Based on Metal-Insulator Transition

For electronic applications, we have fabricated VO₂ thin-film variable resistors (varistors) using metal-insulator transition regarded as the abrupt current jump. The increase of the number of parallel stripe patterns in the varistor leads to the increase in current below a current-jump voltage, which endures a high surge voltage with high current and short rising time. Electrostatic discharge (ESD) experiments show that the varistic coefficient of 500 is larger than 30-80, which is known for commercial ZnO varistors. In overvoltage-protection tests applying high ESD voltages up to 3.3 kV to a varistor, the maximum response voltage is lower than 200 V at an ESD voltage of 1600 V, and the electronic response time is less than 20 ns. This is sufficient to protect a device perfectly.     

ZnO压敏电阻器复合添加剂制备技术

论述了利用化学共沉淀法制备ZnO压敏电阻器复合添加剂的原理和方法,讨论了氨水、碳酸氢铵等8种试剂作为沉淀剂的可行性。实验结果表明,合理地选择复合沉淀剂和沉淀条件,可以显著地提高压敏电阻器的通流能力、降低残压比,并可降低烧结温度和成本,有广阔的推广应用价值。     

半导体激光器电源防浪涌电路的设计

本文利用氧化锌压敏电阻、瞬态电压抑制器(TVS)以及慢启动电路设计了一款应用于半导体激光器的防浪涌保护电路,通过实际测量开关插拔瞬间电路的浪涌波形以及防浪涌保护的实际效果,测试结果证明该电路能够对该浪涌起到良好的防范作用,实现了对半导体激光器的防浪涌保护.     

Zn2SiO4掺杂对氧化锌压敏电阻性能的影响

采用普通陶瓷工艺制备了Zn2SiO4掺杂的氧化锌压敏电阻,研究了Zn2SiO4掺杂量对氧化锌压敏电阻的致密度,晶粒微观结构,小电流性能和通流能力的影响.结果表明:当Zn2SiO4掺杂量达到0.75％(摩尔分数)时,氧化锌压敏电阻晶粒致密均匀;电学性能得到改善,压敏电压梯度和非线性系数分别高达438 V/mm和85,漏电...     

A Suitable Method for Ecovehicles to Control Surge Voltage Occurring at Motor Terminals Connected to PWM Inverters and to Control Induced EMI Noise

A method that is suitable for ecovehicles, which controls the surge voltage appearing at motor terminals that are connected to a pulsewidth modulation inverter with short leads that are less than the critical cable length (i.e., the shortest length at which full reflection may occur), is described here. Also, a method to control electromagnetic interference (EMI) noise, which is induced by the surge voltage, is discussed. Ecovehicles have the problem where insulation degradation of motors occurs due to the surge voltage being repeatedly applied to motor terminals during long lifecycles. EMI noise such as the shaft current and the radiated noise, which are induced by the generated surge voltage, easily diffuse into other electric devices due to the high-density packaging structure. The diffused EMI noise may cause a malfunction of the vehicle controller. An EMI noise controller is studied, which can meet the high-density packaging requirements for ecovehicles like electric vehicles. The EMI noise controller is attached on the motor terminals and simultaneously suppresses the surge voltage and the noise. After clarifying surge voltage characteristics and a circuit model for expressing the surge phenomenon through experiments and simulations, an EMI noise controller is proposed, which uses a multilayer printed power circuit technique. It is verified through simulations and experiments that the proposed controller has the ability to simultaneously control the surge voltage and the EMI noise, such as the radiated noise and the shaft current (the bearing current), which are induced by the surge voltage.     

ZnO压敏元件雷电流冲击试验残压波形分析

研究了ZnO压敏元件在8/20 ms雷电波冲击试验时的残压波形。实验观察到残压波波前尖峰来源于所采用的放电回路触发元件——铜球间隙;在RLC回路临界点附近,随着冲击电流峰值的增大,残压波波尾从非振荡衰减过渡到大幅度的过零振荡;残压波峰值超前于电流波峰值,说明ZnO压敏元件在冲击电流作用下呈现出电感性,且放电电流越大,呈现的电感性越大;元件厚度越大,呈现的电感性也越大。     

Co3O4在压敏陶瓷中的作用和影响

研究了Ｃｏ３Ｏ４在ＺｎＯ压敏陶瓷中的作用，以及它对电性能和微观结构的影响。Ｘ光衍射（ＸＲＤ）、扫描电镜（ＳＥＭ）和电子探针（ＥＰＭＡ）分析结果表明，在ＺｎＯ压敏陶瓷中Ｃｏ离子以Ｃｏ２＋的形式存在，多数Ｃｏ离子已溶入ＺｎＯ晶粒中，形成替位或填隙缺陷，但它基本上不影响ＺｎＯ晶粒的生长。电性能测试结果表明，适当的氧化钻含量能提高ＺｎＯ压敏陶瓷的非线性系数和通流能力，并能降低漏电流和限制电压，然而过多的氧化钻则会对回升区大电流特性带来损害．此论点至今在国内外尚未见到类似的报道。     

Quality assessment of ZnO-based varistors by 1/f noise

Noise has been used as a diagnostic tool of surge arrester varistor structures comprising of ZnO grains of various type and size. The physical and electrical properties of the measured samples have been described. In the experimental study, the applied measurement system and the results of noise measurements for the selected structures of varistors designed for the continuous working voltage 280 V, 440 V and 660 V have been presented. Noise properties are related to electrical characteristics of the measured specimens giving more distinctive results than their voltage–current characteristics. It is suggested that the proposed procedure can be applied as an effective non-destructive testing method focused on defects and structural heterogeneity detection in the tested objects to assess their preparation processes.