A substation could be a portion of an electrical generation, transmission and distribution network. The assembly of equipment accustomed modification some characteristics (e.g. frequency, voltage, P.F., A.C. to D.C. etc.) of an electrical source are termed a station.
Some of the most important actions of substations are:
To receive the transmitted power at Extra high voltage from the generating stations.
To reduce the voltage to an appropriate value for native distribution.
To deliver switching facilities.
Power might flow through many substations between generating station and end user, and its voltage might modification in many steps.
Substations usually have protection, switching and controlling instrumentation, and transformers. In a giant station, circuit breakers are used to interject any short circuits or overload currents that might occur on the network. Smaller distribution stations might use recloses of circuit breakers otherwise fuses for safety of distribution circuits. Sub-stations themselves don't typically have generators, though an influence plant might have a station near. Difference devices like capacitors and voltage regulators may additionally be settled at a station.
Substations might be on the surface in enclosed enclosures, concealed, or situated in special purpose buildings. High rise buildings might have many indoor sub-stations. These indoor sub-stations are typically found in town areas to scale back the noise from transformers, for reasons of presence, or to shield switchgear from exciting climate or fumes conditions.
Where a station features a metallic fence, it should be correctly grounded to guard individuals from high voltages that will occur throughout a fault within the network. Earth faults at a substation will cause a ground potential increase. Currents rolling within the Earth's surface throughout a fault will cause metal objects to own a considerably completely different voltage than the bottom beneath human feet; this bit potential presents a danger of electrocution.