“…The fault rate for the seven future weeks and true health state are tabulated in Table X. To clarify, actual faults were assessed by a hybrid method combining the Roger's ratio and Duval triangle method to construct a fault database, which was proposed in our previous work [18] [31]. In most cases, the transformer condition was healthy; only rare cases with DT faults and some cases with thermal faults, particularly for T3 occurred, which matched the actual fault type distribution.…”