Perturbation identification via voltage phasor monitoring in transmission systems

Monitoring devices such as PMUs have made available direct measures of node and branch phasors. These quantities could be useful especially in promptly detecting emergency conditions and/or starting specific special protection schemes. This paper points out correlations, in variational terms, between monitored node quantities, voltage phase-angles and magnitudes, and single elementary events potentially affecting a transmission system. For sake of generalization an analytical support is also presented. In the end, to validate the proposed approach, an event identification and location module has been developed and tested within a transient stability program.