The power system environment presents various sources of stochastic disturbances. Phasor estimation requires a chain of devices, mainly instrument transformers and phasor measurement units, whose operation is affected by such stochastic disturbances that can hinder the accuracy of the estimation itself. This thesis adopts a simulation-based sensitivity and uncertainty analysis framework to analyze how Discrete Fourier Transform??based phasor estimation during transmission system faults is impacted by current-transformer saturation, capacitive voltage transformer parameter degradation and transient behavior, and phasor measurement unit clock jitter. Furthermore, an attempt to assess which stochastic parameters are the main drivers behind these disturbances is performed, in order to lay the groundwork for future mitigation strategies.