s?a mã ngu?n]Harmonics are periodic distortions of voltage, present-day, or energy sine waves. Harmonics in electric power distribution systems are sometimes attributable to non-linear masses like switched mode dc power supplies and adjustable velocity motor drives.M?t s? ng??i ch?i b? t?c khi liên t?c th?t b?i và “xa b?”, h? tìm ??n công