The Research Of On-off Six-wave Rectifier In Electrolytic Manganese Industry

Electrolytic manganese industry has always been energy-intensive industries, thecurrent efficiency is about65%~75%. Electrolytic manganese is made by high powerrectifier unit on the alternating current into direct current to the cell; make cellreaction negative pole and positive pole, reduction of manganese metal. Factors thatinfluence efficiency of electrolytic manganese current with temperature,concentration, PH and additives, etc. And some research suggest that added to the cellif able to block the poles of the DC current, and under the proper on-off frequency,the current efficiency can improve the quality. Due to the direct current electrolysismanganese can amount to several thousand to tens of amperes, if realize with DCbreaker directly is very difficult to stop. Therefore develop a cut-out of high-powerrectifier is necessary, to delve into the DC flow’s influence on the electrolysisefficiency.This paper briefly introduces the emm process of manganese electrolysis currentefficiency and measures to improve, studying the high power thyristor rectifier unit-6pulse wave rectifier operation mode. And the article puts forward6pulse waverectifier can be shut off the implementation of the scheme. Using Matlab simulationsoftware for power shut off6pulse wave rectifier modeling, Analysis the influence ofthe current waveform control parameters on the grid. The simulation results show that,Cut-out is realized by using block trigger pulse method is feasible, but the systemneed to adjust the control frequency, make the net side current harmonic content assmall as possible, at the same time, also note current waveform symmetry of theproblem.The block6pulse wave rectifier and its control system are designed, and realizeto the control function of the on-off. Hardware circuit including synchronous voltagedetection circuit, pulse amplification circuit, photoelectric isolation circuit, and pulsetransformer output circuit, DC voltage and current sampling circuit and a variety ofprotection circuits, etc. Software part has realized the adaptive phase sequence, faultjudging, trigger Angle control and trigger pulse trigger sequence control.A small block6pulse wave rectifier and its control system prototype aredeveloped, the prototype was tested and studied; the experimental data under differentparameters are analyzed. The experiment results show that, block6pulse waverectifier as a pulse generator, the on-off frequency and duty ratio parameters such as the impact on the current waveform is bigger. when the on-off frequency is constant,the duty ratio, the greater the symmetry of three phase current, the better; duty ratio isconstant, on-off frequency is lower, the symmetry of three phase current, the better,the lower the harmonic content. At the same time, pulse power cycle should be integertimes frequency cycle.