Phase Shifting Transformer has played an important role in electrical networks to improve their efficiency because it has the ability to control power flow in electrical transmission network that can lead to power loss minimization. PST technology is considered as mature technology which is used by transmission system operators. These transformers provide an integrated solution to control power due to the advantages of low economic and high reliability. In this research an exposure to the classification of phase shifting transformers and their application then a simple model for Phase shifting transformer is suggested without seeking in the details of transformer, this model presents the result for using PST via modeling phase shifting voltage, this model is performed using Matlab/Simulink program according to differential equation. Depending on the mathematical model which has been built in an Matlab environment we have a model shows the impact of this transformer through the representation of output voltage , results are verified using Neplan program via a case study demonstrated the role of this type of transformers in controlling power flow in transmission system achieving remarkable power loss reduction and improving voltage profile