Experimental Study On Variation Regularity Of Motor Drive Current In Rotary Kiln

Rotary kilns are large process equipment which are widely used in metallurgical and chemical industries. The physical and chemical phenomena in rotary kilns are complex. In the industrial production, some production process parameters are detected to recognize conditions in the rotary kilns, the kiln motor drive current as a very important process parameters can comprehensively reflect the calcinations in the rotary kilns and operation of the equipment.Now the research about kiln motor drive current is mainly about the qualitative analysis based on actual conditions and experience. Although these conclusions can be the guidance to manufacturing process, it is limited to manual control rather than automatic control. So, the study on the quantitative relationship between kiln motor drive current and operating parameters and to establish proper mathematical model are highly valued both theoretically and practically.In this paper, we research on the kiln motor drive current with experimental method based on the research status and achievements at home and abroad about it. We designed a laboratory rotary kiln which has similar mechanical structure and driving methods with industrial kilns as a experimental subject and developed a real-time acquisition system with software and hardware about kiln motor drive current. This real-time acquisition system can be used to acquire and save kiln motor drive current, kiln speed and the images of the material in the kiln. A series of experiments about kiln motor drive current in different speed and weight of material were completed based on the acquisition system and the waveform figure of kiln motor drive current was acquired. The periodical changing rule of current was preliminary analyzed based on the waveform figure of kiln motor drive current and by means of frequency spectrum analysis, we found that the period of current is equal to the period of kiln speed. The axis location of rotary kiln was measured using image processing technology. Analyzed the data of axis location by means of frequency spectrum analysis, the result indicated that the period of current was caused by the deviation of rotating axis. And then we built the regression model about mean value of kiln motor drive current by analysis of the mean value of kiln motor drive current in different kiln speed and weight of material, deduced the quantitative relation between the mean value of kiln motor drive current, kiln speed and weight of material. The research results of this paper provide a reliable basis to improve the level of automatic control of rotary kiln and have important theoretical and practical significance.