A substation is a division of an electrical generation, distribution and transmission system. Substations convert voltage from high to low, or the overturn, or execute any of numerous other vital functions. Between the generating station and customer, electric power might flow through several substations at varied voltage levels.
Substations might be owned and operated by an electrical efficacy, or might be owned by a large commercial or industrial client. Usually substations are unattended, relying on SCADA for remote control and supervision.
A substation might include transformers for changing voltage levels between the lower distribution voltages and high transmission voltages, or at the interconnection of two varied transmission voltages. The word substation comes from the being prior the distribution system became a grid. Since central generation stations became larger, smaller generating plants were transformed to Electrical Substations, receiving their energy supply from a larger plant despite of utilizing their own generators.