Development Of Intelligent Mill Measuring Instrument Based On DSP

Ball mill is an indispensable material grinding equipment in industrial production.It exists in the scene where there are grinding demands for all kinds of materials,such as beneficiation,lime,cement,coal and other industries' materials.At present,the ball mill's energy consumption is a huge number accounting for more than half of the total energy of the entire industrial system.The work of mill accompanied by blocking,full grinding,cause it to be in low production efficiency.The data of mill production show that the power consumption?grinding yield and the maintenance cost will reach the optimum value if the mill works at optimum load condition.If we can measure the working load of the ball mill timely through the intelligent equipment and control the imported and export materials of the mill to keep the grinding state at high efficiency,it will have a very important significance.This thesis show us a intelligent grinding sound measuring instrument based on DSP aiming at the demand of load monitoring in the process of mill.The mill measuring instrument is mainly composed of hardware circuit and software control program.The hardware circuit mainly includes core signal acquisition circuit,audio processor circuit,display screen interface circuit and output interface circuit.The software part mainly consists of five parts: initialization module,signal acquisition module,core processing algorithm module,graphic display module and output interface module.The work process of the intelligent mill sound measuring instrument is to collect the noise signal from the mill,adjust the spectral range for analyzing according to the data characteristics,select the spectral range that reflects the working state of the mill,and calculate the sound intensity of the selected band so that we can predict the working state of the mill according to the mill sound.Furthermore,the device can output current 4~20mA to the Distributed control system(DCS),which guide the staff to make a reasonable control of the process of feed and discharge to ensure efficient production of mill.After the joint debugging of hardware and software,the intelligent grinding sound measuring instrument can collect the grinding sound signal effectively and display the sound spectrum and sound intensity.Finally,the mill measuring instrument was installed in ball mill production line for trial operation in a cement plant,in Chongqing,Fengdu.The results show that the instrument can indicate sound intensity accurately when the mill is in different working conditions,such as the empty load,the full load and the normal load after the set of the spectral range of mill working.It generates a 4~20mA standard current signal outputted to the DCS,which provides the advanced detection means for the efficient production of the mill,reduces the maintenance costs of mill and reduces labor intensity of the workers.