Scott-T Transformer - Interconnection

Interconnection

At this time two-phase motor loads also existed and the Scott connection allowed connecting them to newer three-phase supplies with the currents equal on the three phases. This was valuable for getting equal voltage drop and thus feasible regulation of the voltage from the electric generator (the phases cannot be varied separately in a three-phase machine). Nikola Tesla's original polyphase power system was based on simple to build two-phase four-wire components. However, as transmission distances increased, the more transmission line efficient three-phase system became more common. (Three phase power can be transmitted with only three wires, where the two-phase power systems required four wires, two per phase.) Both 2-φ and 3-φ components coexisted for a number of years and the Scott-T transformer connection allowed them to be interconnected.