Papers by Keyword: Bode Plots

Abstract: The paper presents the results of study of corrosion resistance of Vanadis 6 steel after conventional heat treatment and sub-zero treatment at-140 °C for 17 h. It was found that sub-zero treatment leads generally to decrease in corrosion current, which is in turn reflected in lower corrosion rate of the material subjected to this kind of treatment. The corrosion potential of sub-zero treated specimens was more anodic, suggesting their more noble behavior in 3.5 % NaCl water solution. This behavior was ascribed to the presence of a huge number of small globular carbides in SZT specimens, which seemed to stabilize the protective oxide films on the surfaces. Tempering reduces the corrosion resistance of the steel since this treatment produces fine precipitates of alloyed carbides that deplete the matrix by chromium and thereby destabilizes the protective films on the steel surface.

Abstract: In this paper, the traditional passive loop filter is improved, and a new type of Cascade Third-order filter structure and Graphical Phase Design method is proposed, which greatly simplifies high-order PLL filter’s design, analysis and calculation. According to graphical phase design principle, parameters for cascade third-order filter could be figured out from the given formula, the derived result is simulated in the form of Bode plots and Unit-step response with Pspice software and the loop target under different parameters is compared. Experiments show that this third-order filter could significantly improve the stability of PLL, deeply attenuate the phase detector’s high-frequency noise and is well adapted to the loop gain change. Users can also change the design parameters flexibly according to the system requirements with this filter.