Yes, indirectly, by using the PLL as a demodulator to extract the sidebands from the 50/60 Hz "carrier" frequency. These types of problems usually boil down to reducing the signal bandwidth as far as you can in order to get rid of as much noise as possible, and the loop filter in a PLL can be good for that.
Some terms to Google for more information on that would be "synchronous detection" and "lock-in amplifier."
The method in the article talks about Fourier transform techniques, but in reality, this is a correlation problem that doesn't have to be handled in the frequency domain at all. Essentially you'd do a dot product of the contents of a sliding window from the recording against the utility's own recording of the AC power waveform. When the peak value is reached, the window offset corresponds to the best estimate of the signal's position with respect to the timeframe of the recording. This benefits tremendously from bandpass filtering, in terms of saving computation time, but doesn't strictly require it.
In real life, you'd use the STFT or something like it as the author describes, but you'd use it as a convolution filter, not to locate the frequency peak. That's kind of a red herring in an otherwise-excellent article.
Some terms to Google for more information on that would be "synchronous detection" and "lock-in amplifier."
The method in the article talks about Fourier transform techniques, but in reality, this is a correlation problem that doesn't have to be handled in the frequency domain at all. Essentially you'd do a dot product of the contents of a sliding window from the recording against the utility's own recording of the AC power waveform. When the peak value is reached, the window offset corresponds to the best estimate of the signal's position with respect to the timeframe of the recording. This benefits tremendously from bandpass filtering, in terms of saving computation time, but doesn't strictly require it.
In real life, you'd use the STFT or something like it as the author describes, but you'd use it as a convolution filter, not to locate the frequency peak. That's kind of a red herring in an otherwise-excellent article.