This paper contains the analysis of existing, as well as possible future application of Phasor Measurement Units (PMU) in frame of interconnection of large-scale power systems. The work is based on the real example – interconnection between EU and Russian power systems. The paper reviews the technical specification of PMU, data concentrators and information output instruments as modern dynamic monitoring system for power grid. The analysis have shown, that application of PMU in power system nodes gives a better opportunity to observe power system’s state, to make optimal decision on planning or protection measures, to perform a forecast, to choose optimal management scheme etc.