Research And Application Of Relationship Between Operation Frequency And Efficiency Of Mine Main Fan

The mine main fan plays a crucial role in the safe production of the coal mine,and its operation status directly affects the safety and reliability of the mine ventilation system.In order to study the frequency conversion and operation efficiency regulation of the main fan,this paper sets up the experimental platform of the variable frequency fan to determine the parameters of the fan and analyze them.Finally,in combination with the actual conditions of the Xiadian Coal Mine,we perform the frequency conversion adjustment of the Xifeng well fan and the Dongfeng well fan to meet the current production requirements.In this paper,we carry out the experiment of frequency conversion characteristics of mine main fan,deal the data by least squares method and get the operating efficiency curves at different frequency.The experiment shows that under the same blade angle and different frequency,the change trend of the air volume Q-efficiency?curve is consistent.With the increase of the air volume Q,the efficiency?increases at first,and then gradually decreases after reaching the highest point of efficiency,and the highest efficiency point of different frequency is different.At the same blade angle,with the increase of the operating frequency,the highest efficiency point appears to increase trend.At the same operating frequency and different the blade angle,the highest efficiency point is different and as the blade angle increases,the highest efficiency point increases.In addition,the pressure curve of the process of frequency conversion from large to small at large blade angle becomes more and more similar to the pressure curve of frequency conversion from small to large at small blade angle.In the process of frequency conversion large to small at large blade angle,the efficiency becomes smaller gradually,and the efficiency becomes smaller gradually during frequency conversion small to large at small blade angle.This paper takes Xiadian Coal Mine as an object,and adjusts the frequency of Dongfeng and Xifeng well fans.The Dongfeng well fan maintains the blade angle of+3°,and adjusts the operating frequency from 45Hz to 50Hz,and its air volume increases from 5016.6m~3/min to5601m~3/min,and the corresponding efficiency increases from 69.45%to 70.72%.The Xifeng well fan adjusts from the blade angle+3°frequency 47Hz to the blade angle+6°frequency45Hz,and the air volume increases from 6292.8m~3/min to 6869.13m~3/min,and the corresponding efficiency increases from 66.58%to74.48%.This shows that the efficiency of the two fans improves after adjusting the frequency of the two fans at meeting the current production requirements.