浅谈有载分接开关的可靠性

从机械寿命、最短维护周期、型式试验等不同角度简述了有载分接开关的可靠性，并通过对国内外有载分接开关结构性能的探讨来证实有载分接开关可靠性的重要程度。     

有载调压变压器分接开关的运行和维护

指出有载分接开关运行中的注意事项,并从检修维护角度提出维护分接开关的注意事项.     

电力变压器有载分接开关运行中的维护

针对电力变压器有载分接开关运行中,由于维护不当易出现的故障,分析其原因及危害性,提出预防措施,同时阐述了有载分接开关维护的重要性。     

有载分接开关过渡电阻配置应注意的问题

有载分接开关过渡电阻配置应注意的问题王肇宽（吴江开关总厂）有载调压变压器的制造厂订购有载分接开关时，在提出有载分接开关的型号、规格的同时，均需要把该有载调压变压器的有关参数提供给有载分接开关制造厂，以便有载分接开关制造厂按此参数配置合适的过渡电阻。然...     

一起变压器有载分接开关故障的检测及分析

利用变压器有载分接开关测试仪对带有分接开关的变压器进行检测，有效地发现一重大隐患，保证了变压器的安全运行。同时提出将变压器有载分接开关切换波形检测做为预试项目一部分的重要性。     

新型无弧有载分接开关研制的可能性

本文针对上前机械式有载分接开关存在的问题，论述了开发新型有载分接开关的必要性，了新型无弧分接开关的原理，阐述了无弧分接开关实现的可能性。并针对实际开发中的有关问题，阐述了作者的见解，并提出了建议。     

变压器有载分接开关常见问题的分析和处理

1引言有载调压变压器在电力系统中应用非常普遍,有载分接开关起着稳定电压的重要作用,做好有载分接开关的维护工作,对变压器的安全稳定运行起着非常关键的作用。     

湖北电网100kV及以上有载分接开关统计分析

对河北电网中的有载分接开关数量,型式,故障情况进行了全面的调查,提出了防止故的措施,以促进有载分接开关的安全,可靠运行。     

变压器有载分接开关故障分析及维护

分析了变压器有载分接开关常见故障发生的原因,并提出了解决和正确维护的方法.     

基于单乙炔测量的变压器真空有载分接开关状态监测

本文中作者分析了一些变压器真空有载分接开关故障案例,提出通过监测真空有载分接开关乙炔含量及增长速率可以有效发现真空有载分接开关存在的潜伏性电气故障。     

关于滚筒洗衣机门锁开关进行软件评估的探讨

本文主要基于家电通标GB4706．1-2005《家用和类似用途电器的安全第一部分：通用要求》和特殊标准GB4706．24—2008《家用和类似用途电器的安全洗衣机的特殊要求》,对滚筒洗衣机门锁开关是否需要进行软件评估进行探讨。并结合笔者平时在滚筒洗衣机测试中的积累,给出滚筒洗衣机需要做软件评估的判断依据。     

A Hybrid dc-to-ac Polyphase Variable Frequency Converter

A method to combine a thyristor switch with a rubbing contact distributor in order to produce a polyphase square-wave output from a dc supply is described. The switch operates sequentially on each phase and is rated at a fraction of the total output of the converter. An experimental converter was used to study the problems of transferring the static switch from phase to phase without sparking under various loading conditions. A successful 6-kW laboratory converter was evolved, capable of operation on inductive and resistive load from 50-Hz to zero output frequency with a high efficiency. The economic features of the system and its application are discussed.     

场畸变触发开关新型触发电极的设计与实验

气体触发开关是脉冲功率电路的重要组成器件。针对工程中对低抖动、长寿命气体触发开关的需求,结合三电极场畸变型触发开关,设计一种拥有较多孔隙的多环型触发极结构。对三种主电极-触发极分别为平板-多环、平板-圆盘、球冠-圆盘的开关进行击穿特性实验研究,结合电场仿真对比分析实验结果。实验结果表明:在22.4k V/40ns的触发脉冲和5.0~7.5k V的工作电压下,平板-多环结构的开关时延及抖动比较稳定,开关时延基本在81.0~84.5ns之间,抖动为0.8~1.1ns。平板-多环电极结构开关时延、抖动均明显优于平板-圆盘结构,其开关时延、抖动与球冠-圆盘结构基本相同但使用寿命优于球冠-圆盘结构。     

基于单片机的电流故障录波系统设计与实现

针对电流超限使用或因用户末端短路造成的跳闸保护情况,设计实现了基于单片机的电流故障录波系统;系统以单片机为核心,对配电单元的电流信号进行采集,与设定电流阈值比较,异常时将电流故障信号传输至上位机处理显示。从硬件电路和软件实现等方面介绍了系统的设计,测试证明,该系统能够有效记录故障波形,减少故障的处理时间及停电时间,同时有利于事后查找故障的原因。     

Three-phase induction motor operating from single-phase supply with an electronically controlled capacitor

In this paper the performance of a three-phase induction motor operating from single-phase supply with a new electronically controlled capacitor using an electronic switch in series with a fixed capacitor to achieve a minimum unbalance of the motor phase voltages at all loading conditions is proposed. No mechanical or centrifugal switch is used here. Basic system operation, theoretical analysis, simulated and experimental results in comparison with conventional operation using one and two fixed capacitors are presented in this paper. The optimum effective capacitor value can be on-line adjusted at any operating speed by periodically changing the duty cycle of the controlled switch to achieve minimum unbalance in phase voltages to improve the motor performance at different speeds.     

应用最小路－广度优先搜索的配电系统可靠性评估

配电系统可靠性是电力系统可靠性的一个重要组成部分,越来越为人们所关注。采用的最小路和广度优先搜索相结合的算法,重点介绍了基于最小路的可靠性评估方法,并以C 语言编程实现广度优先搜索算法求取网络的最小路集。由于主馈线不同的接线方式对系统可靠性指标也会产生不同的影响,针对某地区配电网络一次接线图进行可靠性评估。此方法能够同时考虑配电网络最小路上元件和非最小路上元件对负荷点可靠性指标的作用,并充分考虑了分支线路、隔离开关、负荷开关和备用电源等的影响,为工程技术人员准确地发现配电系统的薄弱环节提供了重要依据,并验证了此算法的有效性。     

新型触头材料电接触行为测试技术及试验研究

为研究微机电系统（MEMS）开关的失效机理,设计了一种以压电陶瓷电动机为核心的新型超低速致动形式的触点材料电接触行为测试分析系统。应用该系统对典型触头材料在闭合和分断过程中的接触力特性、滞回特性、接触电压特性和电弧特性进行了初步观测和物理解释。     

An experimental investigation of a reactor‐type current limiter by cancellation of a noninductive state with power semiconductors

This paper presents experimental results on a new type of current limiter using a model current limiter. This type of current limiter consists of a reactor with two coils reverse wound so as to maintain the noninductive state in the core. A parallel circuit with a power semiconductor switch and a resistor is connected to one of the two coils in series. Maintaining the noninductive condition by turning on the semiconductor switch during the normal loading state, theoretically there is no voltage drop across the limiter, that is, the impedance of the limiter remains at zero. The limiter has a current limiting impedance value during current limiting performance under short circuit conditions. The principle is that, when turning off the semiconductor switch, the resistor is inserted in the circuit, so that the noninductive condition is canceled. The effects of the turn ratio of the reactor winding and the characteristics of the inserted resistor with linear and nonlinear characteristics are experimentally studied. The normal current through a semiconductor is reduced by taking a high winding turn ratio of the coil connected to a semiconductor. On the other hand, the voltage across the semiconductor terminals during the current limiting period increases in proportion to the winding turn ratio of the coil. The current limiting impedance and energy absorption of nonlinear resistors during the current limiting period are numerically analyzed and compared, and a method to determine the optimum winding ratio is proposed. © 2000 Scripta Technica, Electr Eng Jpn, 132(2): 19–28, 2000     

Single switch quadratic boost converter with continuous input current for high voltage applications

In this paper, a novel non-isolated very high step-up DC-DC converter is presented. The introduced converter benefits from various advantages, namely, very high voltage gain, low voltage stress on the active switch, and continuous input current with low ripple. Therefore, the presented converter is suitable for renewable energy applications. In addition, the energy of the leakage inductance of the coupled inductor is successfully recovered, and the voltage spike of the active switch is clamped during the turn-off process. Hence, a switch with low can be used, which decreases the conduction losses as well as cost of the converter. Furthermore, the voltage stress of the output diode is decreased, which reduces the reverse recovery problem. The steady-state analysis and design considerations of the proposed converter are discussed. Finally, the theoretical analysis is validated with the experimental results at an output power of 150 W.     

A new approach to switching, fault protection, and overloadmonitoring of distribution transformers

The major current monitoring and control functions for distribution transformers include: switching transformers in and out of the distribution system; sensing and interrupting secondary faults; sensing and interrupting primary faults; and monitoring transformer loading with indication and isolation capability. A novel primary switch and overcurrent protector device for handling all these requirements is presented. The device's sensor element and magnet latch are described, and its testing and application are discussed. Although it is designed specifically for use in overhead, completely-self-protected transformers, it could be modified for use in pad-mounted transformers