A teardown of a huge (2 full size 19" racks) UPS system, the APC SmartUPS VT 40 kVA, a run down of the power electronics of the system.
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The power distribution board contains all input, output, gate drivers and filtering for the 3 smaller power inverter boards.
The 3 power inverters have each their own heat sinks and seems to consist of 3 different bridges. For battery charging, for AC to DC conversion and DC to AC conversion. I can not tell which bride goes where, as most of the large power traces run inside a 4 layer PCB.
3 different types of silicon is utilized in the inverter, IGBT, MOSFET and diodes. There is two sections of each 6x 47N60C3 MOSFET rated for 600 V and 47 A, 141 A pulsed. First section uses diodes DSEI30-06A rated for 600 V and 30 A, 250 A pulsed. Second section uses diodes DLA60I1200HA rated for 1200 V and 30 A, 850 A pulsed. The IGBT section in the middle uses FGH40N120 IGBT rated for 1200 V and 40 A, 120 A pulsed. Multiply versions of the 40N120 exists called FGL, FGH, FGW and seems to be about different diodes and current ratings.
