Substations are the convenient place for installing synchronous condensers for the purpose of improving power factor and it provide facilities for making measurements to monitor the operation of the various parts of the power system. Substations are provided with safety devices to disconnect equipment or circuit at the time of faults. Some substations provide facilities for switching operations of transmission lines, others are converting stations. Their main functions are to receive power transmitted at high voltage from the generating stations and reduce the voltage to a value suitable for distribution.

It is an assembly of electrical components such as bus-bars, switchgear apparatus, power transformers etc. Substations are important part of power system and form a link between generating stations, transmission systems and distribution systems. These are generally known as substations.

Between the power generating station and consumers a number of transformations and switching stations are required. High voltage transmission lines are used to transmit the electric power from the generating stations to the load centers.

Electric power is produced at the power generating stations, which are generally located far away from the load centers.