Harmonics are periodic distortions of voltage, present, or electric power sine waves. Harmonics in electrical power distribution units are often brought on by non-linear loads such as switched method dc electricity materials and adjustable pace motor drives.T.Huy XSMB: Gi?i ??c bi?t k?t qu? x? s? Mi?n B?c ???c bao nhiêu v?y m?i ng??i ?i!K?t qu? x?