Harmonics are periodic distortions of voltage, latest, or electrical power sine waves. Harmonics in electrical power distribution techniques tend to be brought on by non-linear loads such as switched mode dc energy provides and adjustable speed motor drives.Nh?ng l?u ý khi anh em soi kèo nh?n ??nh m?t hay nhi?u tr?n ??u nào ?ó di?n ra trong ng�