Some applications of phasor measurements to adaptive protection Academic Article uri icon


  • The application of microprocessor based phasor measurements to new adaptive protection schemes is presented. The concepts of digital adaptive protection in which relay characteristics are modified in response to external signals and conditions in the system are examined. The importance of real-time phasor measurements in adaptive protection systems is illustrated by two examples. The first involves obtaining synchronizing information about phasor measurements to be used in a new type of current differential protection for a multiterminal line. By estimating the reference angles for the phasor measurements the effect of synchronized sampling can be obtained without the expense of synchronizing equipment The second use of phasor measurements in adaptive protection is the adaptive setting of out-of-step blocking and tripping. Traditional problems of setting out-of-step blocking and tripping are caused because the settings are, of necessity, compromises based on off-line studies. By reacting to real-time phasor measurements from selected buses in interconnection it is shown that improved out-of-step blocking and tripping is possible. 1988 IEEE

published proceedings

  • IEEE Transactions on Power Systems

author list (cited authors)

  • Thorp, J. S., Phadke, A. G., Horowitz, S. H., & Begovic, M. M.

citation count

  • 81

complete list of authors

  • Thorp, JS||Phadke, AG||Horowitz, SH||Begovic, MM

publication date

  • May 1988