Flow of voltage transformation and power transmission
1. Substations inside (or alongside) the power station
* Step up voltage from the power station output (approx.20kV) to ultra-high voltage from 275kV to 500kV.
* Transmit electricity to Ultra-high voltage substations.
2. Ultra-high voltage substations
* Step down the ultra-high voltage transmitted from the substation in the power station to 154kV.
* Transmit the electricity to primary substations.
3. Primary substations
* Distribute 154kV electricity to railways or large factories.
* Step down the voltage to 66kV and transmit to secondary substations.
4. Secondary substations
* Step down 66kV to 22kV.
* Distribute electricity to factories
* Transmit the electricity to distribution substations.
5.Distribution substations
* Step down 22kV to 6600V
* Distribute electricity to factories or offices
* Transmit the electricity to
6. Pole transformers
* Step down 6600V to 200V or 100V
* Distribute electricity to houses or small offices