Impact of phase shifting transformers on cross-border power flows in the Central and Eastern Europe region

Unscheduled power flows are a serious problem for the Central and Eastern Europe (CEE) region. One method of reducing these undesirable flows relies on the use of phase shifting transformers (PSTs). This paper presents how the installation of PSTs on the Polish-German and Czech-German borders affects cross-border power flows in the CEE region, as well as interactions between these devices. The essential parameters proposed for PSTs are based on the effects arising from the application of PSTs on the border between Poland and Germany. The results demonstrate that the use of PSTs in the CEE region can provide effective control of active power flows in tie-lines and significantly reduce unscheduled flows. However, the operation of these devices must be coordinated in order to achieve maximum controllability and to guarantee the secure operation of the interconnected systems.