In a Rail network wherein we have Grid Substation (PCC) connected to Auxiliary Network (supplying auxiliary loads some of them with rectifiers) & Traction Network (Singe phase loads which has inverters/rectifiers); which network which would be dominant source causing harmonics at PCC ?
the single-phase traction load will create issues of unbalance (negative phase sequence)
the type of rectification used on the trains will dominate the current and voltage harmonics at the PCC. Uncontrolled or thyristor rectifiers will create very high harmonics, which can dominate not just at the PCC but deeper into the public network. Newer units with active front ends to the converters, which shape the current waveform, are relatively benign, so voltage harmonics at the PCC might then be dominated by conditions on the public network
the single-phase traction load will create issues of unbalance (negative phase sequence)
the type of rectification used on the trains will dominate the current and voltage harmonics at the PCC. Uncontrolled or thyristor rectifiers will create very high harmonics, which can dominate not just at the PCC but deeper into the public network. Newer units with active front ends to the converters, which shape the current waveform, are relatively benign, so voltage harmonics at the PCC might then be dominated by conditions on the public network
