Phasor Measurement Units (PMUs) are being widely installed in modern power systems worldwide. The most important advantage of PMUs is their capability to provide fast, reliable and synchronized real-time measurements of different system parameters. This characteristic leads to an essential role of PMUs in real-time monitoring, advanced power system protection, and advanced control schemes. In this paper, a new scheme for controlled separation of two real power systems, i.e., British Columbia and Alberta power systems, based on PMUs synchronized measurements of angles is proposed. Two indices, based on region center of angle and kinetic energy function are obtained for the two power systems. The results demonstrate the reliability, speed and efficiency of the proposed scheme in comparison to the existing installed scheme.