Harmonics are periodic distortions of voltage, existing, or power sine waves. Harmonics in electric power distribution methods are often a result of non-linear loads including switched method dc electric power supplies and adjustable velocity motor drives.K?t qu? x? s? toàn qu?c t? ??ng c?p nh?t liên t?c t?ng gi?i nh? ng?i xem tr??c h?i tr??ng x?