Contribution of phase shifting transformers to improvement of the security of power transfer from the power plant

The paper presents a case study of the use of phase shifting transformer (PST) for improvement of security of power transfer from a power plant. The phase shifting transformer is used for increasing real power flow from the plant to higher voltage level (220 kV), i.e., redistributing the real power flows, and such reducing loading of heavily loaded 110 kV lines. This re-distribution of power flow from the plant results in local transmission network becoming more secure. The local network performance, with and without PST in place, is analysed in both steady state and transient conditions. Interconnection model of Southeast Europe, which consists of transmission network models of Albania, Bosnia and Herzegovina, Bulgaria, Croatia, Greece, Macedonia, Montenegro, Romania, Serbia, Slovenia, Turkey and part of Ukraine is used in simulations. All simulations are made using PSS®E software.