Online Monitoring and Early Warning of Subsynchronous Oscillation Using Levenberg–Marquardt and Backpropagation Algorithm Combined with Sensitivity Analysis and Principal Component Analysis

Table 4

Sample assessment results.

Sample number	Attenuation factor			Frequency (Hz)			Predicted results and classification
	Theoretical value	Predictive value	Error	Theoretical value	Predictive value	Error	Divergence	Classification correctness
1	−4.318	−4.308	0.010	43.13	43.064	−0.066	No	Correct
2	−3.493	−3.483	0.010	43.27	43.291	0.021	No	Correct
3	−2.935	−2.885	0.050	43.29	43.278	−0.012	No	Correct
4	−4.224	−4.151	0.073	43.14	43.180	0.040	No	Correct
5	1.038	1.127	0.089	38.44	38.430	−0.010	Yes	Correct
6	1.152	1.193	0.041	43.30	43.360	0.060	Yes	Correct
7	−5.414	−5.448	−0.034	42.88	42.874	−0.006	No	Correct
8	−3.566	−3.499	0.067	42.02	42.022	0.002	No	Correct
9	−3.865	−3.917	−0.052	42.45	42.431	−0.019	No	Correct