Which PSU and drivers do I need ?

[Boyan Silyavski]

what i learned here on the forum here from Dean

-to get the needed transformer necessary secondary winding voltage we divide the 70DC/1.4= 50 Vac
-due to the fact that the drive uses PWM - On and Off cycle, the actual current use will be 60-70% at most , so say using 4 x 4.1A motors =16.4A so 65% = ~ 10.6A
so at 50VAC and ~10A, we are looking at 500W toroid transformer
-the secondary 2x50VAC must be wired in parallel !
-capacitor has to be around 10 000mf for that setup , at least x1, more will not hurt, it must be >100VDC rating
- >35A 100Vdc Bridge rectifier, the bigger the better, heatsink

That will give you on output 50VACx1.4=70VDC when rectified