As the material level to further improve power down, production has continued to increase. When production reaches its maximum , level continues to increase, the mill power and yield decreased. Due to increased production but decreased the material level , the mill is not working state of homeostasis . And therefore can not work in manual state.
In manual mode , the left side of the ball mill can only work in maximum power point , in fact, due to the material level is no sensitive and reliable means of measurement , the actual operating point far less than the maximum output point . This is the flaw habit runs. In the area corresponding to the feeding habits of the curve is called operation area , the energy consumption in the region of about 50% of the ball , namely, the energy of the ball is about 50% of ineffective . Maximum output point to the right mill power consumption than a habit of running a small area , large production runs than the customary area . Energy in this region is less than 25% of the balls is invalid . But the mill work in this state is not self-stabilizing , only to work properly under automatic control conditions . This area is determined to optimize the operation of our district .
Power ball - see curve a material level characteristics for mill power load that is expected bit is 0 , then the power is about 90 % of the maximum power . With the improvement of the material level , the power first and then decreased , the power tends to zero when the tank is full . Curve 2 , steel touch power ( power consumption of the ball ) , with the improvement of the material level , the steel touch power first and then decreased , touching the steel tank full of power tends to zero . 3 is a power curve coal (coal power consumption ) , the bit with the increase of the material , coal power decreases . Steel ball touch the power and loss, liner loss , vibration, size is proportional to the noise. Coal and coal production is proportional to the power . I.e., curve 1 is the total power , reactive power curve 2 , the curve 3 is the effective power . Curve 1 Curve 2 and curve 3 is equal to the sum that is equal to the total power reactive power and active power . From the above analysis we can know the difference between the actual operation area and optimize the operation area is used to feed bits , or " big coal storage in coal ." Coal pulverizer mill in direct impact power output loss and ineffective . As long as the material is located in the control position , the minimum reactive power consumed by the mill , but the yield increase hair . So the question becomes mill economy optimal control problems material level .