“…Alternative to traditional model-based approaches, data-driven FD (Wang, Xu, Han, & Elbouchikhi, 2015;Yang, Qin, & Saeedifard, 2016) has been developed, which offers powerful tools to extract useful information for FD based on the available voltage and current measurements. Among the data-driven methods, support vector machine (SVM) is employed to diagnose the fault (Li, Liu, Zhang, Chai, & Xu, 2019), and intelligent optimization algorithms (Li, Deng, Wei, Xu, & Cao, 2011;Li, Wang, Gooi, Ye, & Wu, 2017;Liao et al, 2017;Wang, Zhang, Song, Liu, & Dong, 2019;Zeng et al, 2018) are adopted to optimize the key parameters of SVM so that accurate FD can be achieved. It should be noted that the results in FD of MMC so far have been mostly focused on the model-based research (Li, Shi, Wang, & Wang, 2015;Xu, Xie, Yuan, & Yan, 2017;Zhou, Yang, & Tang, 2018).…”