Skip to main content

Typical power system network and components

Short answer

A power system consists of generation (6.6–11 kV), generator step-up transformer, transmision lines (132–400 kV), grid substation, sub-transmision (66/33 kV), distribution substation (33/11 kV), 11 kV primary feeders, distribution transformers (11/0.4 kV), and 400/230 V secondary network, with switchgear and protection at each stage.

Draw a typical power system network and name its different components.

A power system network is the chain of equipment that generates electrical energy, transmits it over long distances and distributes it to consumers.

 GENERATION        TRANSMISSION       SUB-TRANS.
 [G]11kV-[GT]==== 220/132 kV ====[S/S]== 66/33 kV
 [G]11kV-[GT]====      ||           |
                  (other grids)     |
 DISTRIBUTION                       v
               [33/11 kV substation]
                         |
            11 kV primary feeders
               |                 |
         [11/0.4 kV DT]   [11 kV industry]
               |
     400/230 V LT lines -> houses, shops

Components and their functions

ComponentFunction / typical rating
Generating station (G)Hydro/thermal/solar plant producing 6.6–11 kV
Generator transformerSteps up to transmission voltage
Transmission linesCarry bulk power at 132/220/400 kV
Grid substationSwitching, interconnection, step-down to 66/33 kV
Sub-transmission lines66/33 kV to distribution substations
Distribution substation33/11 kV transformation
Primary feeders11 kV lines to load areas, large consumers
Distribution transformer11/0.4 kV near loads
Secondary (LT) network400 V 3-phase / 230 V 1-phase to consumers
Switchgear and protectionCircuit breakers, relays, isolators, LAs at each stage
Control centre (Load dispatch)Monitors and controls the whole system (SCADA)

Generation produces power, transmission moves bulk power efficiently over long distances at high voltage, and distribution delivers it safely at usable voltage to each consumer.

✓ Answer checked by Claude Opus 5.5 (high effort)

Related questions

All Power System Analysis I chapter 1 questions →