Optical fiber imaging for high speed plasma motion diagnostics: applied to low voltage circuit breakers

An integrated portable measurement system is described for the study of high speed and high temperature unsteady plasma flows such as those found in the vicinity of high current switching arcs. An array of optical fibers allows the formation of low spatial resolution images, with a maximum capture rate of 1×106 images per second (1 MHz), with 8 bit intensity resolution. Novel software techniques are reported to allow imaging of the arc; and to measure arc trajectories. Results are presented on high current (2 kA) discharge events in a model test fixture and on the application to a commercial low voltage circuit breaker

Modeling and Simulation of Low Voltage Arcs

Modeling and Simulation of Low Voltage Arcs is an attempt to improve the physical understanding, mathematical modeling and numerical simulation of the electric arcs that are found during current interruptions in low voltage circuit breakers. An empirical description is gained by refined electrical measures and fiber optics based imaging. Ways to assess with a graded scale the interruption performance of a circuit breaker are developed. A theoretical review of the arc plasma physics allows to gain an insight in the governing phenomenon, namely the balance between particle energy gain from the electric field and particle energy redistribution through collisions. The elaboration of this idea to a more abstract level of modeling detail allows to develop a new black box model, based on non equilibrium theory and with increased realism, as well as to address the problem with predictive purposes by means of a computational, multi-physics approach.Electrical Power EngineeringElectrical Engineering, Mathematics and Computer Scienc

Anti-centromere antibodies in 2 patients with discoid lupus erythematosus and no signs of systemic sclerosis

n/