Some applications of phasor measurements to adaptive protection

Conference · Thu Jan 01 04:00:00 EST 1987

OSTI ID:6355719

Thorp, J S; Phadke, A G; Horowitz, S H; Begovic, M M

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. 24 refs., 8 figs.

• Research Organization: Cornell Univ., Ithaca, NY (USA); Virginia Polytechnic Inst., Blacksburg (USA); AEP Service Corp., Columbus, OH (USA)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6355719
• Report Number(s): CONF-8705108-1; ON: DE87009823
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420800* -- Engineering-- Electronic Circuits & Devices-- (-1989)
COMPUTERS
CONTROL SYSTEMS
DATA ACQUISITION SYSTEMS
DESIGN
ELECTRONIC CIRCUITS
MICROELECTRONIC CIRCUITS
MICROPROCESSORS
REAL TIME SYSTEMS