DISTRIBUTION BOARD WITH NEUTRAL CURRENT DETECTOR AND ZERO-PHASE HARMONIC ACTIVE FILTER

摘要

PURPOSE: A device for detecting the current of a neutral line and electricity distributing box with an active zero-phase harmonic filter are provided to install an active zero-phase harmonic filter in an electricity distributing box of a three-phase and four-wire power system, thereby attenuating zero-phase harmonic waves. CONSTITUTION: A neutral line current detecting device(100) detects the currents flowing in a neutral line of an electricity distributing box. An active zero-phase harmonic filter(200) reduces the amount of zero-phase harmonic currents which are inputted from the neutral line of the electricity distributing box. The detection unit detects information about the temperature of the active zero-phase harmonic filter. A controller(240) generates a PWM signal by analyzing the information. The active zero-phase harmonic filter is protected from an overload.