(3) summary of the invention:
The present invention is directed to the moisture instability problem that online tobacco shreds drying bloating plant exists, a kind of control method that improves online bloating plant moisture content of outlet stability is provided.
The present invention adopts following solution:
This control method may further comprise the steps:
(1). to the undulate quantity of the inlet moisture of equipment, be superimposed upon on the control water setting value, realize the stable precompensation of outlet moisture in cut tobacco;
(2). when equipment exported moisture in cut tobacco away from setting value, control water setting value was appended significantly;
(3). when equipment exported moisture in cut tobacco relatively near setting value, control water setting value was revised by a small margin;
(4). when the approaching setting value of equipment outlet moisture in cut tobacco, retentive control water regulating valve opening value.
The present invention analyzes comparison and control to pipe tobacco inlet moisture and moisture content of outlet by control program, has improved the stability of equipment outlet moisture in cut tobacco accordingly, compares with existing control mode, and the qualification rate of moisture in cut tobacco improves more than 20%.
(5) specific embodiment:
Fig. 1 has provided the flow chart of pipe tobacco by equipment, and pipe tobacco passes through inlet Moisture Meter 1, control sprinkler head 2 and moisture content of outlet instrument 3 successively from pipe tobacco moisture regain equipment.The following regulation of intercropping during to each section:
The A section time: under the condition of normal operation, pick up counting when below inlet Moisture Meter 1, putting into mark, stop timing, continuous three times and average to the porch of HXD.
The meaning of determining this section period is: determine that the pipe tobacco (moisture in cut tobacco data record) of inlet Moisture Meter 1 below arrives the time at control sprinkler head 2 places, the moisture data of tested pipe tobacco are preserved and time-delay, and the time of time-delay is exactly that pipe tobacco arrives HXD porch (top of control sprinkler head 2) from inlet Moisture Meter 1.After the moisture data arrive delay time, take out the undulating value that moisture in cut tobacco data and HXD setting value relatively calculates moisture.Be used to control the calculating of water setting value stack amount.
B section time: HXD is treating the material state, and the porch of pipe tobacco being put into HXD picks up counting, and discharges to arrive moisture content of outlet instrument 2 and stop timing from the exit of HXD when pipe tobacco for continuous ten times and average.
The meaning of determining this section period is: the pipe tobacco of definite control sprinkler head 2 tops arrives the time of HXD moisture content of outlet instrument 3 belows, and the B section time is identified for judging the time of adjustment when the approaching setting value of HXD moisture content of outlet and arrival setting value.
By following steps equipment moisture content of outlet stability is controlled:
(1). the inlet Moisture Meter 1 to HXD is carried out data acquisition, data are preserved and the actual material of delaying time when arriving the top of control sprinkler head 2, the difference of dividing setting value with these data and HXD inlet water (proportion is generally between the 0.5-1.0) by a certain percentage is superimposed upon on the setting value of control water and eliminates the fluctuation of supplied materials moisture to exporting the influence of moisture in cut tobacco.
(2). in the moisture of HXD outlet pipe tobacco during (>| ± 0.45%|HXD moisture content of outlet setting value), control amount of water rapidly by control water PID (P ratio, I integration, D differential regulator) moisture of equipment outlet is got back in the normal range (NR) away from setting value.
(3). when HXD exports moisture in cut tobacco relatively near setting value (<| ± 0.3%|HXD moisture content of outlet setting value), setting value to control water remains unchanged earlier, retention time is institute's elapsed time (B section time) below the pipe tobacco above the control sprinkler head 2 arrives HXD moisture content of outlet instrument 3, when these pipe tobaccos arrive the below of HXD moisture content of outlet instrument 3, equipment outlet moisture in cut tobacco is carried out data acquisition and calculates mean value, judge that whether amount of water is suitable, carries out suitable correction to amount of water.
(4). when HXD outlet moisture in cut tobacco arrives setting value, the aperture of retentive control water regulating valve, process time-delay (B section time) collecting device moisture content of outlet is again judged.Enter next control circulation.
Fig. 2 has provided control program block diagram of the present invention.Wherein:
SP: the setting value of online bloating plant HXD outlet moisture in cut tobacco, with % (moisture content of pipe tobacco) expression.
The measured value of PV:HXD outlet moisture in cut tobacco is represented with %.
Sp new: calculate the setting value of the control water yield that makes new advances, usefulness L/H (rise/hour) expression.
Sp old: the setting value of the control water yield that the last time calculates, usefulness L/H (rise/hour) expression.
Factor: the span of control limit of control (empirical value) of the control water yield.
The setting value and the measured value of moisture Sp and moisture Pv:HXD moisture content of outlet.Represent with %.
30 seconds: the B section time (pipe tobacco of control sprinkler head top arrives institute's elapsed time of HXD moisture content of outlet instrument below)
Use above control mode and former control mode relatively, the qualification rate of moisture improves more than 20%.