数字化直流接地系统绝缘检测仪的设计与开发

文章重点阐述了基于 89C5 1单片机设计和开发具有数字显示。

ZJD—4电脑直流接地系统检测仪

介绍ＺＪＤ－４电脑直流接地系统检测仪的原理，技术应用，设备特点。

一种应用于交直流不接地系统绝缘监测装置的设计与开发

介绍了一种用于工业不接地系统的绝缘监测装置(IMD),针对现有技术的不足,提供了一种新的硬件平台,可监测400V等级的交直流不接地系统,并详述了绝缘监测仪的硬件和软件设计原理。目前该绝缘监测仪已通过试验验证,并在市场上大量销售,为工业不接地配电系统提供了可靠的绝缘监测。

地中敷设绝缘层降低直流接地极跨步电压的方法研究

为利用有限的土壤面积尽可能的降低直流接地极的跨步电压,以圆环形直流接地极为研究对象,提出了一种地中敷设绝缘层以降低跨步电压的方法。结合矩量法和边界元法对敷设绝缘层的接地极性能进行了分析,并通过现场实验验证地中绝缘层降低跨步电压的有效性。计算结果表明:地中敷设绝缘层能够有效抑制接地极入地电流流入表层土壤,从而均衡地表电位,降低跨步电压;在不增加任何其他措施的情况下,采用U形绝缘层能够有效降低直流接地极跨步电压10%以上,且该方法对接地极本身性能的影响较小。

直流漏电检测中的数字锁相放大技术

在介绍直流系统漏电检测原理的基础上,提出一种全新的微弱信号检测法。该方法采用 DSP(数字信号处理器)和采样 ADC(模数转换器)实现数字锁相放大器。在整数个周期内对被测信号进行采样得到信号序列,由数学运算得到参考序列,通过计算信号序列和参考序列的互相关函数就可实现数字相敏检测。同时还对数字相敏检测的频率特性进行了分析,给出了实际设计的数字锁相放大器。

Application of DC component to select fault branch in arc suppression coil grounding system

When single phase earth fault occurs in the arc suppression coil grounding system, the amplitude of the transient capacitance current is high and decays fast, but the attenuation of the transient inductance current is much slower. This paper analyses the DC component of fault branch, and has found it is much bigger than that of the normal branches in transient state. All the simulation results obtained from three compensation types, different fault time and different wave cycles show that the DC component of fault branch is much higher than that of those normal branches. These results verify the effectiveness of taking the DC component as the method of fault line selection in the arc suppression coil grounding system.

Research on Common Grounding Electrode Technique in HVDC

This paper discusses the characteristics of DC transmission common system ground electrode type and shared ground electrode, established the mathematical model of two circuit DC systems share ground electrode, analyze effects of the shared loop ground DC transmission system electrode on the operation of HVDC system size under different operation modes, and compare with the independent ground electrode, ground electrode impact on environment under different operation mode, and the paper finally puts forward some solving measures for the influence of the shared ground electrode on the environment and public ground electrode effects on DC system operation problems.