High Frequency Capacitive behavior of field stop trench gate IGBTs operating in Short Circuit
A wide experimental characterization about the input capacitance of Field Stop Trench Gate IGBTs is presented. It was achieved thanks to a novel experimental set-up which allows us to measure the input capacitance in the active region where the device operate during the Short Circuit (SC). The experimental results have been interpreted with the help of FEM simulations which confirm that negative capacitance is correlated with the accumulation of holes at the interface between N- IGBT base and gate oxide.
Instabilities in Silicon Power Devices: A Review of Failure Mechanisms in Modern Power Devices
In the last 15 years, the global demand for power saving, efficiency, and weight, size, and cost reduction in both the consumer and the industrial fields have strongly pushed the research and advancements in electronic power systems. Today, electronic power systems cover nearly the full voltage range (from volts to megavolts) and almost the full power range, if we exclude gigawatt-rated power plants. The applications include:smart grids . distributed power systems . photovoltaic (PV)/wind power stations . transportation (heavy/light traction, automotive, avionics, etc.) . industry applications (motor drives, arc welding, etc.) . consumer electronics (switch-mode power supplies, household appliances, etc.).
Tests of composite beams with web holes
Tests of composite beams comprising a concrete slab supported on a steel deck and a steel wide-flange shape containing large web openings are described. Special attention is directed to the amount of shear connection between slab and steel section in the region of a web hole, and on the effect of construction loads acting on the steel section prior to composite action being effective.It is shown that limited shear connection at the hole will significantly affect the strength when loading produces a high shear-to-moment ratio, and a theory is presented which conservatively takes this into account. The effect of construction loads on unshored construction is shown to be small when these do not exceed 60% of the non-composite beam resistance at the hole.