Harmonics are periodic distortions of voltage, present, or ability sine waves. Harmonics in electrical power distribution devices tend to be due to non-linear masses which include switched mode dc electrical power supplies and adjustable pace motor drives..) b?n l?u ý l?i nh?p li?u. Trong ?i?u ki?n có th? MinhNgoc luôn Hello?n ho?c trong m?t kho