The application of electric energy metrology to electrified railways is mainly studied.Aiming at the problem of strong harmonic interference at traction substation of electrified railways

the full-electronic watt-hour meter of three-phase four-wire system based on the principle of "time division multiplier" is put forward to be installed in high-tension side of traction transformer by large numbers of tests and researches to reduce harmonic interference and to increase the correctness of electric energy measurement.The researches and discussions on the electric energy measurement methods of other nonlinear loads are carried out too.