Electric Utility

It gives the test results of a few typical samples to analyze the difference in the effect of moisture and aging on FDS curves.  (a) and (b) take A1 and A4 samples as examples, respectively, to show the effect of moisture on frequency domain dielectric spectra. It can be seen that the frequency-domain response curves of dielectric loss increase with increase in the moisture content for both unaged and severely aged samples, and there is a difference of nearly two orders of magnitude between dry samples and severely damped samples.

The oil-paper insulation system in power transformers operates under the effects of high temperature and strong electromagnetic environment, and the insulation medium can slowly decompose into a number of small molecules. The decomposition gases dissolved in oil are H2, CH4, C2H6, C2H4, C2H2. When a fault occurs, the insulation breaks down more quickly and the decomposition products will be different according to the type and severity of the fault.

In this paper, a novel silicon-on-insulator (SOI) lateral-double-diffused metal-oxide-semiconductor field-effect transistor (LDMOSFET) is presented. Changing charge distribution leads to lower electric field crowding and increased breakdown voltage (VBR). For modifying charge distribution, a metal region (COLUMN) and an air layer inside the transistor are utilized. On the other the floating-body effect and impact ionization generate excess holes that are amplified by the parasitic bipolar junction transistor (BJT) in SOI-LDMOSFET that degrade the transistor performance.

propagation coefficient has many relations for cable.It is clear that there is more “rough jitter” in the spectrum of the last 500MHz than that of the first 500MHz. This is due to the additional influence produced on the spectrum by the extra capacitance introduced from the cable joint as the result of connection, which leads to distortion of the spectrum to some extent.