Block filter for power line communication

摘要

Provided is a blocking filter for PLC, the blocking filter including a low pass filter unit including a capacitor and a plurality of inductors, a plurality of magnetic saturation prevention circuits each connected to the inductor in parallel to prevent magnetic saturation of the inductor, and operating in response to an interruption control signal inputted from outside, and a first switch connected or opened in response to the interruption control signal and interconnected between the low pass filter unit and a neutral line.

主权项

1. A blocking filter for power line communication (PLC), the filter comprising:
a low pass filter unit configured to include a capacitor and a plurality of inductors; a plurality of magnetic saturation prevention circuits each connected to the inductor in parallel to prevent magnetic saturation of the inductor, and configured to operate in response to an interruption control signal inputted from outside; and a first switch connected or opened in response to the interruption control signal and interconnected between the low pass filter unit and a neutral line, wherein each of the magnetic saturation prevention circuits comprises: a current transformer so installed as to wrap a periphery of the power line and to detect an input current proportionate to a current flowing in the power line; a low pass filter configured to filter a frequency signal higher than a predetermined signal in the input current; a phase correction circuit configured to correct a phase difference of an output signal of the low pass filter; an amplification circuit configured to amplify the output signal of the phase correction circuit and to provide the amplified output signal to the inductors; and a second switch connected or opened in response to the interruption control signal and interconnected between the low pass filter and the phase correction circuit.