With the development of power system in our country, the large-scale GTU(Generator Transformer Unit) of different types have been put into operation more and more. When the GTU breaks down, find out the reason, character and position of the trouble seem more and more important. So, it has very significant meaning to install special-purpose fault record device on GTU to analyze the reason, char...

Electric energy is the most important energy. Its application has caused great changes in the production technology. In the modern society electric energy has been applied to the various fields of the society production and the subsistence. Watt～hour meter is the important means of energy measurement and economic accounts. Its nicety directly relates the economy benefit of the Country and t...

This paper has carried on deep analysis and studies to various kinds of capacitive current calculation methods of resonance ground system and compensation principles of arc-suppressing coil, and has pointed out the error that they exist in theory and the necessity of reducing the error. On this basis, the paper has studied and put forward the new method to improve the precision of capacitive c...

Methane explosion accident is always the main threat to the mine production. The two main physical factors of methane explosion are the concentrations of methane and oxygen reaching explosive limits and the existence of fire source. It is very important to measure the distribution of methane concentration in real-time. For a long time, scientists in many countries have been researching on tec...

With the more and more high demand and deep study on the power quality, it asksfor more and higher demand to the power quality analyzer: it should not only has theability to comprehensively analyse power quality indexes, but also has the linking netand mass storage functions, the two functions not only can conveniently measure,analyse and govern the power quality from extensive scope, but also...

This paper aims at developing a system to evaluate the power supply system harmonics effect on energy measurement. Firstly, we analyzed the effect of the classic harmonic sources on the power quality by simulation of arc furnace using Matlab; secondly, by analyzing the structure and principle of induction watt-hour meter, this paper proposed a non-linear improved mathematic model to study its ...

Virtual Instrument has become an important direction of instrument development, now it has been widely used in many fields. FFT analysis is a widely used method in mechanical engineering, fault detection and many other fields. However, the traditional FFT analyzer is expensive and is not easy to be upgraded. The birth of virtual FFT Spectrum Analyzer gets rid of the limitation of traditional F...

grid grounding resistance value is the most important technical parameter of the grounding system in power plant、transformer substation and some other places. Whether right the Ground Resistance value is directly impact on whether safely work the power system can. However, because there are some errors between the design value of ground resistance and the actual value of it, the measurement...

Transmission line is one of the important component parts of power system. The power frequency parameters of transmission line generally include direct current resistance, positive sequence impedance, zero sequence impedance, positive sequence admittance, zero sequence admittance and zero sequence mutual inductive reactance between parallel lines. These parameters are necessary to set up math...

Digital oscillograph is a a sort of intuitionistic, universal,and exact metrical instrument.It is used in the all kinds of study field such as physics, chemistry, biology, mathematics,and physic and project technique such as electronical project, steely smelt, machinery instrument, calculational technique,radar navigation, automata, and universe flight.It is used to test, analyze,and surveil t...