Harmonics are periodic distortions of voltage, present-day, or ability sine waves. Harmonics in ability distribution devices in many cases are caused by non-linear masses including switched manner dc electric power supplies and adjustable pace motor drives.K?t qu? x? s? mi?n B?c trên m?ng c?ng s? ???c c?p nh?t ngay vào lúc 18h15 h?ng ngày b?i t