A Study on High Current Arc Interruption by Multi-Channel Synchronized Diagnosis of Gas Temperature in Circuit Breaker Nozzle.

点击翻译按钮获取中文摘要

Following results are derived from this research project :(1) Transient axial temperature distributions in a post-arc channel in a flat-type SF_6 gas-blast quenching chamber is estimated from relative intensities of two Fe spectral lines at wavelengths of 426.0 and 442.7 nm by the two-line method. In the practical experiment, iron is intentionally used as the electrode material in a flat-type SF_6 gas-blast quenching chamber. Measurements of radiation intensities of these two Fe spectral lines make it possible to estimate post-arc temperature below 3500 K at 100 mus after current zero in the chamber.(2) A method for estimating X_<Fe> is developed on the basis of spectroscopy, which utilizes the relative radiation intensity of background spectra at 455.0 nm to Fe spectral line at 426.0 nm. From the calculation of the coefficients of the background spectra, it is observed that the background spectra at 455.0 nm have not only continuous contribution but also those of S_2 spectra. It is al … More so found that X_<Fe> is of the order of 0.01% around current zero along the arc axis in the chamber.(3) A new concept of 'thermal plasma contacts' is proposed in order to interpret the behavior of a post-arc channel from the viewpoint of transient axial electrical resistivity distribution in a post-arc channel. The fictitious 'thermal plasma contacts' are found to open in the axial direction during arc quenching period with the velocity exceeds 100 m s^<-1>. Furthermore, behavior of the thermal plasma contacts applied TRV of the order of 2 or 3 V mus^<-1> was discussed to give an interpretation on thermal failure and successful interruption.(4) Particle compositions and electrical conductivity of SF_6 plasmas are calculated considering the non-equilibrium effect, i.e.two-temperature effect. In the calculation of particle compositions, effective excitation temperature is newly proposed in order to express the populations of the internal states of heavy particles in high-pressure and high-gas temperature plasma in two-temperature steady state. The effect of an increase in electron temperature is investigated on the variation in particle composition and electrical conductivity of SF_6 plasmas. Less