3 ms·
Obviously 48VDC has been around and internally they will probably still step down to 48V. But these 48V islands are nowadays inter connected by regular AC grid.
by _fizz_buzz_ 7mo ago
Obviously 48VDC has been around and internally they will probably still step down to 48V. But these 48V islands are nowadays inter connected by regular AC grid. They want to replace that interconnection with a 800VDc bus. I kind of assume they chose 800vdc because there are already bunch of stuff available from EVs which also have 800vdc battery packs now.
- 15155 7mo agoThey chose 800VDC because it's a convenient multiple that is the peak possible with a two-level 650V (probably GaN) FET arrangement.
- eternauta3k 7mo agoAnd why is 650V special?
- 15155 7mo agoHistorical, physical, engineering reasons. Much of the world's mains-voltage electronics run at 240V (historical) and have PFC circuits (which are essentially just boost converters) that run at ~400V DC link voltages. 650V gives you enough headroom to tolerate overshoots and still have an 80% safety margin with a single level topology. This voltage also coincidentally is a convenient crossover point where silicon MOSFETs start to become inefficient and GaN FETs have recently become feasible and mass-produced.