Parallel Strings: Cable and SOC mismatch

by VladM

12 parts

Two strings share one 2Ω load through S1 (10mΩ closed, 2.01Ω in all). String A starts at 50.0V on a 10mΩ cable, string B at 49.0V on a 40mΩ cable; each is 15F + 50mΩ. Press Run: the load is on for the first second, then "load cmd" moves S1 off it (about 2 seconds later on screen at ×0.25) and the strings are left to themselves. Real packs: a 1V mismatch over 0.15Ω circulates about 7A the moment two strings are paralleled; why strings are matched in voltage before their contactors close.