Mr.G wrote: ↑30 Aug 2018, 18:00
AJI wrote: ↑30 Aug 2018, 14:12
Mr.G wrote: ↑30 Aug 2018, 08:01
Fuel supply pump? Radios, any other electronic?
Of course, but my point is that they already have a 120kW 'alternator' permanently driven by the crankshaft and another ~90kW one driven by exhaust, both of which charge the ES. There is also a provision in the rules to access unlimited energy from the ES and also store an additional 300kJ of energy outside of the ES specifically for running other ancillaries. Why would they even need another alternator?
Efficiency? Power conversion? Stability? MGU-H/K are probably 400/700V systems... Ancillaries are 12-15V... Safety? No need for special insulation?
The main reason I don't think they have an ancillary alternator is because they are allowed to use the ES, so what would be the point? I am happy to be proven wrong, but to address your specific concerns:
-If your going for efficiency then not having another alternator is sensible, not to mention weight saving. A lot of race cars and bikes don't have an alternator for this reason, just a battery.
-Power conversion isn't really a problem, step-up or down is common in most electronics.
-A 25kg battery pack is pretty stable. They must hold somewhere around 12MJ of capacity and the ancillaries only need a tiny fraction of that. The ancillaries also have their own separate 300kJ buffer. I assume this is for stability?
Almost anything that can be driven by a hydraulic system is driven by the car's hydraulic system, from high pressure pumps right down to throttle butterflies. There is very little ancillary power required. The ECU is probably the most power hungry..?
- The ERS system is limited to 1000V and I'm pretty sure the manufacturers would try and get as close as possible to that number. Just step it down to 12v for ancillaries.
-Safety? How?
-Insulation... There is ~1000V all over the place on a PU. I don't think that's a problem, however, interference could be?