Harmonics are periodic distortions of voltage, latest, or power sine waves. Harmonics in ability distribution units tend to be brought on by non-linear hundreds such as switched manner dc ability supplies and adjustable velocity motor drives.x? s? ki?n thi?t B? tr??ng Tài chính H? ??c Ph?c ch?t v?n casino Vân ??nHello?n, c? n??c có 63 doanh ngh