Papers by Author: Wei Jiang

Abstract: Cascaded H-bridges inverter has been gaining its ground in recent years because it can satisfy high voltage and power applications with medium volume semiconductors; however, it uses much more semiconductors than the traditional inverters which would increase the fault possibilities. Just because this case Cascaded H-bridges inverter is limited in many important industrial fields. In this paper, we, firstly, discussed the basic unit of Cascaded H-bridges inverter (namely, full-bridge inverter) and classify its inner faults, then we proposed a method to spot the faulty IGBT using neural network. We have also done lots of jobs on this fields which could be seen in the papers of our team.

Abstract: With the knowledge of heterogeneous characteristics of thermal barrier coating materials at mesoscopic level, a coupled thermo-mechanical-damage (TMD Model) model was introduced and used to numerically quantify the thermal stresses and crack development of in thermal barrier coatings (TBCs) composite subjected to decreased temperatures. The effect of different surface precrack morphologies, such as precrack length and precrack density, on an interface crack subjected to thermal loading caused by a temperature change is presented. It provides us with a more sensible physical intuition and a more accurate mathematical for optimizing the design and the processing of ceramic coatings subjected to the coupled thermal-mechanical loading.

Abstract: In this paper, a numerical code, Realistic Failure Process Analysis code (RFPA), was used to perform a microscopic analysis of a crack in a fiber-reinforced ceramic, when the crack length is the same order of magnitude as the fiber spacing. The numerical results performed in the paper shown the failure process of fiber-reinforced ceramic subjected to tension loading, which indicate that the reinforcing fibers in a ceramic composite have a significant effect in inhibiting crack propagation even during the stages of the development of crack. Moreover, the fiber evidently increased the load-carrying capacity.