H?i ??ng x? s? ki?n thi?t mi?n B?c bao g?m 28 ??n v? thành viên, trong ?ó có six ??n v? t? ch?c quay s? chính th?c và c? ??nh hàng tu?n c? th? nh? sau:Harmonics are periodic distortions of voltage, current, or electric power sine waves. Harmonics in electricity distribution units in many cases are caused by non-linear masses for instance swi