Two-Stage Fault Diagnosis Method Based on the Extension Theory for PV Power Systems

Table 1

Three different sorts of mathematical sets.

Compared item	Standard set	Fuzzy set	Extension set
Research objects	Data variables	Linguistic variables	Contradictory problems
Model	Mathematics model	Fuzzy mathematics model	Matter-element model
Descriptive function	Transfer function	Membership function	Correlation function
Descriptive property	Precision	Ambiguity	Extension
Range of set	𝐶𝐴(𝑥)∈(0,1)	𝜇𝐴(𝑥)∈[0,1]	𝐾𝐴(𝑥)∈(−∞,∞)