HARMONIC SUPPRESSING CIRCUIT FOR ELECTRIC POWER SYSTEM AND COMMUNICATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To suppress higher harmonics and prevent the production of overvoltage due to ground fault accident by series-connecting a bidirectional switching element with a coil having a required inductance, and exercising control so that the bidirectional switching element will has a constant switching voltage both in positive and in negative. SOLUTION: A coil L is series-connected with a diode anti-parallel circuit 1 having a certain positive and negative switching voltage. Another coil L1 and a capacitor C parallel circuit 5 are added as required to reduce the reactance of the entire circuit. A harmonic suppressing circuit 10a is thereby constituted, and it is connected with a sheath grounding conductor 9. The circuit allows fundamental waves to be passed and yet suppresses higher harmonics.