With the power of the widespread use of electronic devices, power grids in the harmonic pollution is becoming increasingly serious. Now widely used harmonic approach is to minimize harmonic or harmonic filters. Filtering equipment not only the traditional high-cost equipment investment, but also a waste can be used by the harmonic energy. This paper presents a harmonic use of a motor drag the methods and devices, the device can be harmful to the power grid and the electricity sector is being filtered out of the harmonic energy use, used to drive DC motor. Key words: Harmonic Harmonic Harmonic suppression against the passive filter fundamental harmonic drag degaussing circuit希望对你有帮助