20/4/2010

Go through substation categories, type and design. There are 4 types of substation:
PMU-Pencawang Masuk Utama(Transmission Main Intake)
PMU is the interconnection point of 132kv or 275kv to the distribution network .The standard transmission capacity and voltage transmission provided at the PMU are as follows:
-132/33 kv,2*90mva
-132/22 kv,2*90mva
132/11 kv,2*30mva
PPU-Pencawang Pembahagian utama(Main Distribution Substation)
PPU normally applicable to 33kv for interconnection g 33kv networks with 11kv networks. It provides capacity injection into 11kv network through a standardized transformation of 33/11 kv,2*30mva
SSU-Seksyen suis utama(Main Switching Station)
SSU at 33kv,22kv,and 11kv are established to serve the following function:
To supply a dedicated bolts customer(33kv,22kv,11kv)
To provide bulk capacity injection or transfer from a PPU/PMU to a load center for further localized distribution.
P/E-Pencawang Elektrik(Distribution Substation)
P/E are capacity injection points from 11kv,22kv and sometimes 33kv systems to the low voltage network(415v,240v)Typical capacity ratings are 1000kva,750kva,500kva,300kva and 100kva.
Conventional sub-station designs are of indoor type(equipment housed in a permanent building)and outdoor type(Ground-mounted or Pole mounted)
Compact substation (11/0.45kv)has limited application and is to be strictly applied in selective situations under the following circumstances.
-System reinforcement projects for highly build up areas where substation land is difficult to acquire.
-Dedicated supply to a single or limited group of low voltage customers after careful consideration of future expansion needs of the distribution network.
The main reasons for the above application criteria are as follows :
-Compact design reduces future system flexibility in terms of network expansion.
-Compact design features ,which limits the capacity of outgoing circuits.