How to eliminate power line coupling interference in a power line carrier PLC?

Eliminating power line coupling interference in PLC power line carriers requires isolation and filtering measures. An isolation transformer is used to couple the carrier signal, with a primary-to-secondary withstand voltage of 3000VAC, suppressing common-mode interference. A bandpass filter is deployed on the secondary side of the transformer, with a center frequency equal to the carrier frequency and a bandwidth of 10kHz, using an LC resonant circuit CMZ2012A-900T. For differential-mode coupling interference, a common-mode inductor CML4532A-510T is installed at the power line inlet. The coupling path is analyzed through simulation to optimize the isolation and filtering parameters. In actual testing, the coupling interference voltage is measured using an oscilloscope and should be less than 10% of the signal amplitude. Eliminating coupling interference can improve the signal-to-noise ratio by 25dB, significantly improving communication reliability.