Harmonics are periodic distortions of voltage, recent, or ability sine waves. Harmonics in power distribution units are often brought on by non-linear hundreds which include switched method dc energy provides and adjustable velocity motor drives. Gi? x? s? mi?n nam l??ng truy c?p trên h? th?ng Sites Minh Ng?c r?t l?n nên các b?n c?n l?u ý m?t