Transformers and Reactors for Electrical Energy Transmission
Transmission transformers and autotransformers are used to interconnect the separate high voltage transmission systems.
To ensure security of supply, transmission transformers are installed in two, three or four transformer substations, such that, in the event of one transformer being unavailable for whatever reason, the load can be carried by the remaining transformers. To control the power flow in an interconnected network it is sometimes necessary to use a phase shifting transformer.
Long power transmission lines often require shunt reactors to compensate their the line capacitance to earth.