Fig 1.
500kv T connection transmission line.
Fig 2.
Propagation direction of the traveling wave when the T-connection transmission line internal branch AO fails.
Fig 3.
Fault traveling wave propagation direction when an external fault occurs on the T-connection transmission line.
Fig 4.
Corresponding waveform of the traveling wave of the traveling wave protection unit TR1 in the case of internal fault occurred on branch AO of the T-connection transmission line.
Fig 5.
Corresponding waveform of the traveling wave of the traveling wave protection unit TR2 in the case of internal fault occurred on branch AO of the T-connection transmission line.
Fig 6.
Corresponding waveform of the traveling wave of the traveling wave protection unit TR3 in the case of an internal fault occurred on branch AO of the T-connection transmission line.
Fig 7.
Corresponding traveling wave waveform of the traveling wave protection unit TR1 in the case of an external fault occurred on branch BE of the T-connection transmission line.
Fig 8.
Corresponding traveling wave waveform of the traveling wave protection unit TR2 in the case of an external fault occurred on branch BE of the T-connection transmission line.
Fig 9.
Corresponding traveling wave waveform of the traveling wave protection unit TR3 in the case of an external fault occurred on branch BE of the T-connection transmission line.
Fig 10.
ELM network structure.
Fig 11.
Flow chart of the fault branch identification algorithm.
Fig 12.
Power line configuration.
Table 1.
Transmission line parameter I.
Table 2.
Transmission line parameters II.
Fig 13.
Training sample set composition diagram.
Fig 14.
Comparison of training set prediction results.
Fig 15.
Comparison of test set prediction results.
Table 3.
Simulation results of different fault type test sets.
Fig 16.
Comparison of test set prediction results.
Table 4.
Simulation results of different transitional resistance fault test sets.
Fig 17.
Comparison of test set prediction results.
Table 5.
Simulation results of different fault distance test sets.
Fig 18.
Comparison of test set prediction results.
Table 6.
Simulation results of different initial angle test sets.
Fig 19.
Comparison of test set prediction results.
Table 7.
Simulation results of a test set in which the T-connection line near the O point fails.
Fig 20.
Comparison of test set prediction results.
Table 8.
Simulation results of test set Of fault occurred near point O of the T-connection transmission line.
Fig 21.
Corresponding figure of data of the sampling points near the wavefront of the initial traveling wave of TR1 when a fault occurs on branch AO.
Fig 22.
Corresponding figure of data of the sampling points near the wavefront of the initial traveling wave of TR1 when a fault occurs on branch BE.
Fig 23.
Comparison of test set prediction results.
Table 9.
Simulation results of the test set under loss of AO and out-of-band branch road data in the zone.
Fig 24.
Corresponding graph of random loss of 100 data sampling points near the initial traveling wave head of TR1 in the case of BO branch fault.
Fig 25.
Data loss random correlation graph of 100 data sampling points near the initial traveling wave head of TR1 in the case of CF branch fault.
Fig 26.
Comparison of test set prediction results.
Table 10.
Simulation results of the test set under random loss of CF data in the branch road and the outer branch road in the zone.
Fig 27.
Comparison of test set prediction results.
Table 11.
Simulation results of the test set when the branch BO of the T-connection transmission line zone exhibits CT saturation.
Fig 28.
Current-related waveforms measured by the branch BO fault traveling wave protection unit TR1 in the T-connection transmission line zone.
Fig 29.
Current-related waveforms measured by the AD fault traveling wave protection unit TR1 of the external branch of the T-connection transmission line.
Fig 30.
Comparison of test set prediction results.
Table 12.
Simulation results of test set for branch BO and out-of-band branch AD in T-connection transmission zone under different SNR faults.