Comparing the trustworthiness of signal-to-noise ratio and peak signal-to-noise ratio in processing noisy partial discharge signals

In partial discharge (PD) analyses, there is a need to compare the noise level of measured signals in different conditions and/or after applying certain signal processing algorithms (e. g. noise reduction). Moreover, in PD analyses through modelling approaches, whenever noisy signals should be constructed by adding noise with a desired level to the simulated PD signal and/or where de-noising process is employed, there is a need to evaluate the strength of noise. In all these cases, signal-to-noise ratio (SNR) is already used as an indicator of noise level, whereas it is shown that SNR can be deceptive and misleading. Instead, this study recommends employing the proposed peak SNR which is more robust than SNR. The results can be extended to the analysis of any non-periodic transient signal as well.