A Study Of Passive Lossless Snubbers For IGBT Bridge-Inverters

The inverter-bridges of IGBT are applied to big power converting applications more widely with the develop of Power Electronics Technology. Nowadays the snubbers in IGBT inverters are traditional clamp RCD snubbers yet, which can convert some energy back to power supply so that the dissipation is low. But its energy wasting will grow bigger and bigger with the inverter work at higher switch frequency and convert bigger power. In this thesis, a clamp passive loseless snubber is put forward for IGBT inverters after analysing the dissipation of hard switching and soft switching with snubber. Then theoretical analysis and simulation are been take to prove the work of the snubber. And a real inverter circuit and its auxiliary circuits are built. The experiment result shows that the snubber can suppress the over voltage effectively at switch off and its dissipation is little.