Markov模型下的引信安全系统分析

采用Ｍａｒｋｏｖ模型对具有不同逻辑结构的引信安全系统在勤务处理环境激励作用下的安全性进行了分析。以三级保险为例，比较了增加顺序控制、时间窗控制的引信系统与普通引信系统的安全性，对引信安全系统的设计有一定的参考价值。     

变压器中初次级线圈对电容分压信号的影响

在小型脉冲变压器中,常采用分布式电容分压器实现输出电压的实时监测,但实际的测量波形存在畸变,为此根据变压器电容分压等效电路模型,结合ANSYS软件进行有限元仿真计算,分析了脉冲高电压变压器中分布式电容分压器输出信号的主要贡献源及影响程度;用频率响应法测量计算电容分压输出信号的结果表明:分压输出信号中,感应至初级线圈的信号约占24%,初级线圈对电容分压信号的影响较大,是一个重要的干扰源。针对以上结果,利用ANSYS软件进行结构优化,提出了降低初级线圈影响的方法。     

Study on the Pulsed Flashover Characteristics of Solid-Solid Interface in Electrical Devices Poured by Epoxy Resin

In electrical devices poured by epoxy resin, there are a lot of interfaces between epoxy resin and other solid dielectrics, i.e. solid-solid interfaces. Experiments were carried out to study the flashover characteristics of two typical solid-solid interfaces （epoxy-ceramic and epoxy~ PMMA） under steep high-voltage impulse for different electrode systems （coaxial electrodes and finger electrodes） and different types of epoxy resin （neat epoxy resin, polyether modified epoxy resin and polyurethane modified epoxy resin）. Results showed that, the flashover of solid-solid interface is similar to the breakdown of solid dielectric, and there are unrecoverable carbonated tracks after flashover. Under the same distance of electrodes, the electric stress of coaxial electrodes is lower than that of finger electrodes; and after the flashover, there are more severe breakdown and larger enhanced surface conductivity at interface for coaxial electrodes, as compared with the case of finger electrode. The dielectric properties are also discussed.     

聚醚对环氧-聚氨酯互穿网络制备的影响

研究了聚丙二醇醚（PPG）、聚四氢呋喃醚及二者的共聚醚分别形成的聚氨酯预聚体与低分子羟基化合物和环氧树脂的反应性,应用聚氨酯对环氧进行了IPN改性,测试了其红外光谱和冲击强度.结果说明：聚四氢呋喃醚型聚氨酯的反应活性太大,不适宜用于环氧树脂的IPN改性 聚丙二醇醚及其与聚四氢呋喃的共聚醚型的聚氨酯反应活性适中,适合作为环氧IPN改性的聚氨酯组分.采用PPG型聚氨酯对环氧进行了IPN改性,改性后的环氧体系冲击强度大大提高.     

变压器油的体积效应在小型脉冲变压器中的应用

介绍了变压器油的体积效应理论及其在小型脉冲变压器中的应用.