Comparative Performance Study of Dissolved Gas Analysis (DGA) Methods for Identification of Faults in Power Transformer

Table 15

Fault identification results of each DGA methods.

S. no.	Roger’s ratio method	IEC ratio method	Doernenburg ratio method	Duval triangle method	Three-ratio method	Relative percentage of four gas methods	Key gas method
T-1	T2	T2	Thermal decomposition	T1	T1	NR	NR
T-2	NI	T2	Thermal decomposition	T1	T1	T2	NR
T-3	T2	T3	PD	T2	T3	T3	NI
T-4	T2	T2	NI	NI	T2	T1	PD
T-5	NI	NI	NI	NR	NI	NI	Overheat of oil
T-6	T3	T3	NI	NR	T3	T2	NR
T-7	NI	NI	T1	NR	T3	NI	Overheat of cellulose
T-8	T2	T3	NI	NI	NI	T3	Arc
T-9	T4	T3	NI	T2	T3	T3	PD
T-10	T1	T3	NI	NR	T3	NI	PD
T-11	D1	NI	Thermal decomposition	DT	D1	T2	NI
T-12	T3	T2	NI	NI	T2	NR	NR
T-13	NI	NI	Thermal decomposition	D1	D2	T1	Overheat of oil
T-14	NI	PD	Arc	D2	D1	D2	Overheat of cellulose
T-15	T1	NI	T1	NR	D2	NI	Overheat of oil
T-16	T3	T3	NI	NR	T1	NI	Arc
T-17	NI	NI	T1	NR	T1	PD	Overheat of oil
T-18	T3	PD	Arc	T2	T3	T2	NI
T-19	NI	F6	T1	DT	D2	NR	F3
T-20	T3	T3	NI	NR	NR	T3	NR
T-21	T3	T2	NI	NR	T3	T2	Overheat of cellulose
T-22	T1	NI	NI	NI	T1	T2	Overheat of oil