LED 고조파 유출이 누전차단기에 미치는 영향

Recently, as the use of LEDs increases, the influence of harmonics emitted from LEDs is increasing. The generation of harmonics can cause malfunction of other electronic equipments. In this paper, we measured the amount of harmonics emitted from LED. The effect of the generation of harmonics on the earth leakage breaker was also investigated. Harmonics from LEDs are mainly third harmonics, and as the number of LEDs increases, the amount of harmonics increases. In addition, we analyzed the effect of harmonics on the common ELB and recently used IGR (grounded resistance current) ELB, respectively. After generating the 3rd, 5th, and 7th harmonics using the harmonic generator, we checked whether the ELB operated normally. Experimental results show that a typical ELB easily operated on the current of the electrostatic capacity component. When the harmonic was applied, the leakage current was amplified, consequently ELB operated at a lower current value. On the other hand, the IGR ELB was slightly influenced by the current of the capacitive component and harmonic current. However, the IGR ELB did not completely eliminate the current of the capacitance component.