Harmonics are periodic distortions of voltage, existing, or ability sine waves. Harmonics in electric power distribution programs are frequently a result of non-linear hundreds like switched manner dc electric power provides and adjustable speed motor drives.Bên c?nh ?ó, m?t s? gi?i ??u có s? tham gia c?a ??i tuy?n Vi?t Nam c?ng nh?n ???c nhi?u