Click to download PDF —> sld_substation
Above PDF contains two SLDs of substations (220kV into 400V). Below are screen shots.
In the right corner of the image, we can see a SLD of 11kv to 400 v step down. This is frequently asked in interviews. In India generating voltage is 11 kV mostly, but 6.6 kV or 33 kV generation also likely possible.
Single line diagram 0131A
In dg 0131A, we used (i) Bus Bar – 220 kV double bus bar, 66 kV double bus bar, 11 kv Bus, (ii) Incoming – 2 X incoming 220 kV, 5 X Outgoing 66 kV, 1 X outgoing 11kV. (iii) 2 X 100 MVA 3 winding 220/66/11 transformers 3 phase (iv) CT, PT, LA, Wave traps, coupling capacitor, fuse/CB, isolators.