A mesh-based magnetic equivalent circuit has been derived to model the dynamics of wound rotor synchronous machines (WRSMs). A particular focus has been placed on the derivation of flux tubes to model machines with an arbitrary number of damper bars placed at an arbitrary depth in the rotor pole tip. Faraday's Law is applied to establish a state model in which winding and damper bar flux linkages are selected as state variables. The resulting coupled magnetic equivalent circuit/state model is solved to predict machine dynamics. An important attribute of the model is that saturation is represented without the need for a relaxation factor, which enables its use as a practical tool in machine design. Data obtained from hardware experiment and a finite-element model are used to validate the proposed methods.Index Terms-Damper bars, magnetic equivalent circuit (MEC), wound rotor synchronous machine (WRSM).
Time-resolved photon emission has been shown to be useful in analyzing clock skews and timing-related defects in flip-chip devices. In practice, time-resolved photon emission using the S-25 Quantar detector cannot be used at long loop lengths (typically >10 μs). This paper discusses a near-infrared (NIR) optimized time-resolved emission system to demonstrate that even with long loop lengths time-resolved photon emission can be extremely useful for defect localization. Specifically, it describes time-resolved photon emission system, and shows how time-resolved photon emission was used to solve two different issues that caused scan fails on silicon-on-insulator devices, and briefly discusses the interpretation of optical waveforms. The two issues are presented as case studies.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.