A study on non-intrusive blocking filter with non-saturation characteristic to high current

In this paper, a non-intrusive blocking filter for Broadband Power Line Communication(BPLC) without magnetic saturation to high current has been first proposed and designed. The non-intrusive blocking filter consists of a blocking filter core to attenuate BPLC signals and a magnetic saturation prevention circuit to prevent a blocking filter core from magnetic saturation. Ferrite for EMI filter is used as the blocking filter core to obtain broadband attenuation characteristic in BPLC frequency range. The magnetic saturation prevention circuit consists of a Current Transformer(CT), a low pass filter, a phase delay compensation circuit, and a driver circuit. Performance of the blocking filter core is verified to measure attenuation characteristic in the BPLC frequency range. The performance of the magnetic saturation prevention circuit is verified to measure whether a magnetic saturation is caused or not depending on magnitude of current.