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Interconnected system SLD with bus voltages

Short answer

The SLD shows generators at 11 kV stepped up to 220 kV and 132 kV buses, interconnected transmission at 132 kV, sub-transmission at 66/33 kV, primary distribution at 11 kV, and secondary at 400/230 V. Multiple stations feed grid buses through step-up transformers.

Produce a neat single line diagram of an interconnected power system showing multiple generating stations, transmission and sub-transmission lines, and primary distribution lines. Mention all bus voltages in the system.

An interconnected power system links several generating stations through a transmission grid; sub-transmission and primary distribution lines then carry power to load areas.

 G1 11kV          G2 11kV          G3 11kV
   |                |                |
 [11/220]        [11/132]         [11/132]
   |                |                |
 B1 220 kV          |                |
   |                |                |
 [220/132]          |                |
   |                |                |
 B2 132 kV ====== B3 132 kV ====== B4 132 kV
   |                                 |
 [132/33]                        [132/66]
   |                                 |
 B5 33 kV (sub-trans.)           B6 66 kV
   |                                 |
 [33/11]                         [66/11]
   |                                 |
 B7 11 kV feeders                B8 11 kV
   |                                 |
 [11/0.4] -> 400/230 V           [11/0.4] -> LT

Bus voltages

BusVoltageRole
Generator terminals11 kVGeneration
B1220 kVEHV transmission bus
B2, B3, B4132 kVTransmission/grid buses
B533 kVSub-transmission
B666 kVSub-transmission
B7, B811 kVPrimary distribution
LT bus400/230 VSecondary distribution
  • Generating stations (hydro, thermal) feed the grid through step-up transformers.
  • 220 kV and 132 kV lines interconnect the stations and grid substations, forming loops for reliability.
  • 66/33 kV lines carry power to distribution substations.
  • 11 kV primary feeders carry power to distribution transformers and bulk consumers.

These are the levels used in Nepal's INPS (with 400 kV now added for cross-border lines).

✓ Answer checked by Claude Opus 5.5 (high effort)

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