Harmonics are periodic distortions of voltage, latest, or power sine waves. Harmonics in electric power distribution techniques in many cases are a result of non-linear loads for instance switched mode dc electricity materials and adjustable pace motor drives.Tra?nh tr???ng h??p ?ê?n t?i ca?c ?i?a chi? kinh doanh vé s? không uy ti?n, khi ?ó ng?