320kVA可控硅调压器触发电路改造

合成塔电加热器的调压器,一般属感应调压器,因其体积大、造价高、功率因素低、调压操作又不甚方便,故该厂在1983年将其设计并自制为可控硅三相调压器。经多年投运,效果好。1988年大修时,又将其触发器进行了改造,采用集成化相控触发电路,使其具有制作简单、调试方便、调压器输出三相电压均衡度高等优点。本文对其工作原理;相控元件及触发器等进行了论述。     

555定时器的典型电路及其实际应用

介绍555定时器的结构与工作原理,对比分析由555定时器构成的单稳态触发器、施密特触发器和多谐振荡器3种典型电路,举例分析了555定时器的实际应用。     

KCZ6.2型移相触发器及应用

本文系统介绍了KCZ6.2型晶闸管触发器的内部结构、工作原理、电路参数及使用特点,并介绍了KCZ6.2型触发器在电力电子技术中的应用。     

爱尼普拉触发电路应用于氯碱可控硅整流系统

通过两种触发电路的对比分析，阐述用Ｅｎｅｒｐｒｏ触发电路改造锯齿波同步触发电路的可行性、优越性。     

浅析单片机在晶闸管触发电路中的应用

由于计算机的快速发展与进步,其衍生品也在不断的产生、发展,比较具有代表性的产品就是单片机。单片机主要是应用在晶闸管触发电路当中,单片机被运用到很多的电器元件里面,因此,其对电路系统产生了一定程度上的改变与影响。主要是基于晶闸管与单片机的视角上进行分析,对单片机在晶闸管触发电路中的应用进行分析与研究。     

微机触发电路可控硅串级调速系统调试

介绍微机触发电路可控硅串级调速的原理及系统组成,重点介绍其调试方法。     

三相交流调压电路的设计

本文的设计内容是三相交流调压电路采用三相晶闸管反并联无中线的星形联结电路;触发电路的选择采用序列宽脉冲触发相控电路,利用同步变压器实现同步定相,采用脉冲变压器实现主电路与控制电路的电气隔离,控制电路采用单片机控制。从而实现了三相交流调压电路的设计。     

可自启动多模式三相环形脉冲分配器的设计

提出了一种可自启动的多模式三相步进电机环形脉冲分配器的设计方法。首先,通过分析各模式的状态转换关系分别获得各模式下的触发器驱动方程,进而产生模式可选的触发器驱动方程。其次,由驱动方程设计出简化的硬件电路。最后,对自启动进行了讨论,给出了自启动电路设计。实际电路可通过模式设置获得三相单三拍、三相双三拍和三相六拍等三种环形脉冲分配器。     

可靠的自动上盐装置

在电路中巧妙地利用了D型触发器40175的端置位与端正、负跳变之间的特性。实现了所要求的工艺逻辑关系，电路简单、运行可靠，从而保证了自动上盐系统的正常运行。     

Effect of trigger on crashworthiness of unidirectional carbon fibre reinforced polyamide 6 composites

Carbon fibre as reinforcement and polyamide resin as matrix were used to manufacture unidirectional laminates by using hot compression method for investigating the effect of trigger on their crashworthiness and energy absorption capability through static compression tests. Two types of trigger including single and double bevel trigger were used meanwhile six trigger angles from 30° to 80° of each type were employed to investigate the trigger effect. Optical observation was employed to observe the crushed cross section of each laminates to explain the fracture behaviour.     

整流微机触发及其同步方式

介绍了整流系统中微机触发的简要原理以及同步方式对系统的影响。     

1,2-oxazine linker as a thermal trigger for self-immolative polymers

We have demonstrated the site-specific thermal activation of self-immolative polymers (SIPs) using a bicyclic oxazine as a temperature-sensitive triggering moiety. The oxazine-based trigger was installed at the junction of a SIP-poly(N,N-dimethylacrylamide) (PDMA) diblock copolymer via oxidation of hydroxyurea end groups on the SIP and in situ [4 + 2] cycloaddition with cyclopentadiene-functionalized PDMA. The trigger undergoes a thermally-driven cycloreversion which ultimately leads to initiation of the depolymerization process. The temperature dependence of activation and depolymerization were investigated, along with the mechanism of activation. The relative rates of depolymerization at different temperatures suggested to us that the thermal trigger design may be a good candidate for on-demand activation of SIPs with minimal background triggering.     

小型仪表盘报警系统的设计与实现

由继电器搭建的报警系统包括以下4部分:外部信号触发部分,报警指示部分,报警试验、确认部分,报警主动作部分。该报警系统适合信号小于50点的小型控制室及室外小型控制盘,设计与施工费用低。     

蓄电池机车新型直流斩波控制触发板的设计

介绍蓄电池机车新型控制触发板的设计方法。     

亮度自动调节的室内灯光电路的设计

介绍光控电路的设计（包括电源电路、控制电路、主电路）,并介绍其工作原理、参数及特点。     

大功率整流装置触发控制角调控的节能经验

介绍了山东海科胜利电化有限公司合理控制触发控制角（相控角）,有效减少谐波影响的节能经验。     

输油站场ESD触发分析

介绍输油站场ESD系统的设置原则和结构组成．对其双重冗余配置和电液联动执行机构进行说明．分析系统的触发条件和系统特点．     

一种基于触发器的数据管理方法的设计与实现

为了方便、高效地管理RT21-ISCS综合监控系统的各项数据,保证数据的一致性和完整性,针对轨道交通综合监控系统的特点,通过对oracle触发器的合理设计,实现了一种基于模型的数据管理方式.触发器不但处理了各等级模型数据间的复杂逻辑,同时通过定义同步机制,实现了系统内实时数据库与历史数据库的同步,使客户端可以直接访问实时数据库,以提高系统的响应速度和处理能力.     

Leakage currents precede short circuits in PVC‐insulated cable when exposed to external radiant heat

The mechanism of how and when an arcing short or a physical short occurs on a polyvinyl chloride (PVC)‐insulated cable when exposed to radiant heat flux has been found experimentally. How this mechanism acts on the size of the resulting arc beads is also considered. As a physical short usually changes into an arcing short in an instant, it is difficult to determine which type of short circuit occurs as the first phenomenon. To solve this difficulty, a short circuit current was limited to the order of an ampere, which is large enough to trigger an arcing short, and short circuit tests were conducted with a PVC‐insulated cable. Before an arcing short, a small amount of leakage current in the order of milliamperes was observed flowing through PVC insulation, which gradually increased and finally turned into an arc. On the other hand, no leakage current was observed before a physical short. These results indicate the following mechanism: When PVC insulation between conductors in a cable melts when a heat flux is applied, conductors often come close to and into contact with each other. In this case, the leakage current is unrecognizably small because the PVC insulation is not yet carbonized and still has a high resistivity. Meanwhile, when conductors do not come into contact with each other, PVC insulation is gradually carbonized and the leakage current increases until an arcing‐through‐char occurs. Copyright © 2016 John Wiley & Sons, Ltd.