Research on Harmonic Analysis and Suppression Methods in Electrowinning Copper Rectifier

In this paper, a double reverse star rectifying device with an annual output of 20,000 tons of electrolytic copper in a copper plant is taken as the research object. Firstly, the working principle of the double reverse star thyristor rectifying device is analyzed, and the theoretical analysis of its rectifying circuit is obtained. High harmonics present and verified by simulation experiments. Then, for the corresponding harmonics, a harmonic suppression system constructed by the principle of induction filtering is proposed. For the rectifier transformer, in order to achieve the zero impedance of the winding, the harmonic flux of the secondary winding and the filter winding must be equivalent to zero in the design process, thereby providing a flow channel for the harmonics. Finally, according to the overall structure of the system, the mathematical model of the power induction filter rectifier transformer is established, and the filtering effect is designed according to the derived harmonic flow path. In order to better achieve the filtering effect, the DC output current is controlled by the PI controller to achieving a constant value. By constructing a simulation model, the analysis results show that the system can suppress harmonics well.