|Budget Amount *help
¥4,600,000 (Direct Cost : ¥4,600,000)
Fiscal Year 1999 : ¥4,600,000 (Direct Cost : ¥4,600,000)
On the Basis of the successive results of generating a wide area induction plasma by using MOSFET inverter with 450-kHz frequency and 50-kW power in 1998, the further experiments were carried out in the final year of the project, 1999, as follows.
1) Generation of Atmospheric Induction Thermal plasma for SFィイD26ィエD2 and NィイD22ィエD2
Induction plasma for SFィイD26ィエD2 gas medium which has a strong plasma quenching property was, for the first time, generated in inductively coupled mode at atmospheric pressure in this project. The power level was increased from 50 to 200kW, which gives a possibility to do the experiment for high pressure and high power condition equivalent to the actual circuit breaker interruption phenomena.
2) Operation of Pulse Modulated Induction Plasma
The most important facility to proceed this project, the pulse modulated induction thermal plasma, can be generated under several conditions with respect to the pressure(up to 0.1 Mpa), the duty factor and the shimmer current level(down to 40%). The rise and fall time of pulsing is as short as hundreds μs which gives almost ideal pulse-like disturbance to the plasma. It is found that the new facility thus developed gives a detail of dynamic decaying process of high pressure plasmas of NィイD22ィエD2, HィイD22ィエD2 and SFィイD26ィエD2 in repetitive mode.
3) Measurement of SFィイD26ィエD2 and NィイD22ィエD2 Induction Plasma Temperature
The multi-channel detection of the spectrum line from Ar-SFィイD26ィエD2 and Ar-NィイD22ィエD2 induction plasma reveals that the SF6 inclusion gives a strong shrinkage and reduction of the plasma temperature as prospected, while such effects are not enough in the case of NィイD22ィエD2 inclusion. The results showed, however, that the increase of pressure or concentration NィイD22ィエD2 gas gives a emphasis of above quenching effects almost equivalent to SFィイD26ィエD2 gas.