+ B?n c?p nh?t th? công k?t qu? v? h? th?ng c?a mình: (nh?p n?i dung tr? tin nh?n sms, nh?p vào d? li?u ?ng d?ng, nh?p vào World wide web k?t qu? x? s?..Harmonics are periodic distortions of voltage, present, or electrical power sine waves. Harmonics in electric power distribution programs tend to be caused by non-linear masses including swit