Page 483 - Decision Making Applications in Modern Power Systems

Pattern-recognition methods for decision-making Chapter | 17 443

FIGURE 17.1 The structure of pattern-recognition methods.

extraction and decision-making are the primary tasks of automatic pattern rec-
ognition. The computation burden is one of the main challenges of the protec-
tion schemes, and hence, the feature selection as a reduction technique of
construction of a feature vector can be considered in the procedure of the pat-
tern recognitions.
Since distance relays are the most difficult to set in protection relays, and
they need a multiplicity of settings; this section concentrates on outlining the
development of pattern recognition for some functions of distance protective
relays. The procedure of a pattern-recognition-based protection scheme has
essential requirements to be considered:
Identification of function type of protection and, hence, a definition of the
target of protection scheme: A distance relay as a multitask relay has dif-
ferent protection functions. Some of these functions can be a candidate to
replace with pattern-recognition methods. The functions are expected to
issue a trip decision or supervise other performances. In addition to the
existing protection functions, some other auxiliary functions can be
designed to improve the performance of the distance relay. Accordingly,
the target should be identified, then the pattern-recognition model can
make a final decision.