*8.2. Comparative Study*

Performance of the proposed algorithm is compared with the algorithms used for the detection of faults in the presence of renewable energy using DWT [12,13] and Stockwell transform (ST) [14,15]. It is observed that the DWT-based technique effectively detects the faults; however its performance is adversely affected by the presence of noise above 50 dB SNR and generates false tripping signals. Hence, DWT-based technique is not effective for the detection of faults when high noise level of 10 dB SNR is present. The Stockwell transform-based algorithm uses the patterns of various contours and plots for the fault detection, which ranges from half cycle to one cycle. The protection scheme based on the application of proposed WD-index individually will be slow and fault detection time will be high. However, its performance is least affected by the noise. The proposed ALN-index is effective for reducing the fault detection time because it has the merit of sharp change at the time of fault incidence. However, this cannot be used as a standalone protection scheme because at the time of fault incidence, its magnitude increases for the faulty as well as healthy phases. Furthermore, the performance of ALN-index-based method is adversely affected by the presence of high noise level. Therefore, proposed algorithm, obtained using WD-index and ALN-index has the combined merits of these indexes and provide fast performance of protection scheme, further it is not affected by the noise. Hence it is established that the performance of proposed algorithm is superior as compared to DWT, Stockwell transform, standalone WD-index and standalone ALN-index.
