Locating Natural Frequency Faults in HVDC Transmission Systems Based on the Rotation-Invariant Technology Signal Parameter Estimation Algorithm and the Total Least Squares Method

Table 3

S-ESPRIT unipolar HVDC metallic short-circuit distance measurements.

Actual point of failure (km)	Natural frequency principal component (Hz)	Calculated ranging point (km)	Error (%)
20	3737	20.17	+0.85
50	1506	50.04	−0.08
75	1011	74.55	−0.60
100	752	100.23	+0.23
125	604	124.79	−0.17
150	502	150.15	−0.10