CN1544912A - Concentration changing and sending adjusting device - Google Patents

Abstract

The invention is a temperature transducing and adjusting device, specially relating to a device of measuring and controlling fluid concentration, including power concentration transducer, fuzzy adjuster, solid-state relay, valve machine and adjusting valve, all electrically connected in turn, where the power concentration transducer includes sensing component, lever mechanism, photoelectric sensor and force generator, the fuzzy adjuster includes matrix unit and programmable pulse-width modulation (PWM) unit, and the output signal of the fuzzy adjuster is connected to the input end of the solid-state relay. It implements direct control of valve machine; the solid-state relay has no contractor, light control current and high acting speed; it omits adjuster and valve servo amplifier, reduces cost, and enhances reliability, and the control system has small overshoot and responds quickly.

Description

Concentration becomes send regulating device

Technical field

The invention belongs to instrument and meter for automation, automaton, particularly a kind of automation equipment of measuring and controlling fluid concentrations.

Background technology

Homogeneous substance with identical component or same physical, chemical property is called " phase ".Can constitute by one matter or multiple material mutually.Two-phase fluid is meant the dynamic synergistic situation that exists between two-phase or two components in fluid.Compare with monophasic fluid, two-phase fluid is wanted the many of complexity.On the one hand, owing to whenever in the two-phase flow each have one group of flow parameter mutually, the variable of describing motion has almost increased by one times, on the other hand, physical property of the volumetric concentration of each phase, the size of dispersion particle, each phase (density, viscosity etc.) and alternate relative velocity can be in very wide range, and these all can cause the great changes of nowed forming.Heterogeneous fluid concentration is meant the number percent of quality in whole heterogeneous fluid quality of discrete phase in the fluid.Wherein liquid-solid two-phase fluid extensively is present in departments such as chemical industry, metallurgy, the energy, light industry and military project.Paper pulp in the pulp and paper industry is a kind of liquid-solid two-phase fluid.Usually said " pulp density " is meant the mass percent of bone dry fiber material in the potpourri of paper stock (paper pulp and adjuvant) and water composition.

The on-line measurement of liquid-solid two-phase fluid discrete phase concentration is significant to metering, control and the operational reliability of production run.In papermaking, sugaring, food-processing industry production run, extensively need carry out the measurement and the control of material concentration.In for example slurrying production run, on-line measurement and control pulp density can be stablized making beating and bleaching effect; For copying the paper production run, measure and control pulp density in real time, can stablize the online pulp density, improve paper quality.In paper plant, can measure the bone dry fiber amount by measuring pulp density and volumetric flow rate, for the trade settlement between paper plant, the workshop, production cost management provide foundation.Because two-phase flow characteristic complexity, the on-line measurement difficulty of its concentration is very big, though people (both at home and abroad) are studying different measuring methods at different objects, and the detection means thought of convention nothing but still so far.According to the characteristics of different object and liquid fixed double phase flow, at present, the method that people studied has: isotope density method, capacitance method, supercritical ultrasonics technology, optical method and mechanics method.The mechanics method is the method that the extensive engineering of unique energy is used.It comes the concentration of measuring media based on the shear stress principle by the shear stress of measuring sensor and measured medium relative motion generation.

The measurement of concetration instrument (transmitter) of engineering application at present is divided into according to structure type: evolute consistency transmitter, inner-rotary type consistency transmitter, quiet cutter formula consistency transmitter, moving-blade consistency transmitter.Abroad, the more complete unit of measurement of concetration instrument product is the BTG company of Sweden, and its consistency transmitter product is inner-rotary type and moving-blade consistency transmitter.The quiet cutter formula and the evolute consistency transmitter that still have domestic today belong to product of low grade, and BTG company has not produced already.

Interior rotary consistency transmitter is a microcomputer equalising torque digital servosystem, the variation of concentration is reflected in the change in torque on the measurement axis, the moment of torsion increment overcomes the support moment of friction and the moment of elasticity that is connected rubber ring between measurement axis and the driving shaft, make diaxon when rotating, produce relative angular displacement, photoelectric sensor is transformed into electric signal with it and is defeated by microcomputer, the microcomputer FEEDBACK CONTROL makes diaxon keep original relative position, the current signal of FEEDBACK CONTROL is followed the variation of concentration and is changed, and therefore the current signal of output just can reflect concentration.The stability that the inner-rotary type consistency transmitter has high sensitivity to become reconciled, but complex structure involve great expense, and is difficult in maintenance, uses inconvenient.

Moving-blade consistency transmitter moving-blade consistency transmitter structure is made up of sensitive element, measurement axis, driver part (forcer) and circuit unit.Movable member is that fulcrum is made reciprocating swing with the bolster under the acting in conjunction of the constant driving and the resistance of motion, constitutes a movable system of single-degree-of-freedom machinery.Its movement velocity is promptly relevant with concentration by the time of optoelectronic switch, and mimic channel is converted to output current signal with this time.As shown in Figure 1.Moving-blade consistency transmitter performance is only second to the inner-rotary type consistency transmitter, and is better than evolute consistency transmitter and quiet cutter formula consistency transmitter performance, and simple in structure, low cost is safeguarded easily, and is easy to use, very high cost performance is arranged, at home and abroad have a wide range of applications.

At present, the paper plant of large-scale production has has all installed and used concentration varitrol (for example copy the paper production line just need 3 grades of i.e. 3 cover concentration control systems) in a large number, in concentration varitrol shown in Figure 2, moving-blade consistency transmitter P measures the situation of change of concentration in real time, output 4-20mA signal is given all-purpose controller, all-purpose controller is according to the deviation of actual concentrations and setting value, according to certain adjusting rule output 4-20mA conditioning signal, regulating and controlling valve FW aperture, increase or the minimizing dilution water, make the pulp density after the process stock pump mixes reach the setting requirement.Sample valve FS among the figure is used for instrument is carried out the timing signal sampling.

In traditional pulp density regulating system, because electrically operated valve belongs to inertial element Controlled device also belongs to inertial element and pure lag system $\left(\frac{1}{1+T_s}{e}^{-T_s}\right),$ In the moving-blade consistency transmitter sampling period long (T=2s), adopt the PID adjusting of all-purpose controller must produce the serious lag effect; Be difficult to make system to obtain good control effect.The electrically operated valve of widespread use is made up of spool, reducing gear and monophase machine three parts, accepts the control signal of 220V with three terminals (com, open, close) form.When voltage was added on com and the open two-terminal, motor just changeed continuously, and valve does not disconnect greatly; When voltage was added on com and the close two-terminal, motor reversed continuously, and valve constantly turns down.When voltage disconnects, the motor stall, valve is parked in a certain aperture invariant position.This valve need be accepted a formula control signal (220V make-and-break signal), can not directly accept 4～20mA signal.At present, all all-purpose controllers (the no matter still analog form of digital form) are output as 4～20mA standard signal system signal.When adopting the actuator of electrically operated valve action control system (Control Flow, pressure, temperature, liquid level etc.), valve must add the band servoamplifier, could accept the control signal of 4～20mA of regulator, and be converted to the corresponding aperture (0～100%) of valve by servoamplifier.Actual operating position shows that the time-delay that servoamplifier has increased control lags behind, and causes system fluctuation easily; Also improved the cost of valve.A lot of users wish to have and a kind ofly measure after the concentration directly automatically that the automation equipment of control electrically operated valve comes out.

Summary of the invention

The present invention proposes a kind of concentration change and send regulating device, at all-purpose controller (PID adjusting) and the problems of electrically operated valve in moving-blade concentration automatic control system, overcome above-mentioned deficiency of the prior art, a kind of consistency transmitter function that both had is provided, include Fuzzy Controller again, directly control the microcomputer type automation equipment of electrically operated valve with pulse-width modulation PWM signal able to programme.

A kind of concentration of the present invention becomes send regulating device, comprise moving-blade consistency transmitter, regulator, valve driving machine and variable valve, connected by electric signal in regular turn between them, described moving-blade consistency transmitter comprises sensitive element, leverage, photoelectric sensor and forcer, it is characterized in that:

(1) Fuzzy Controller of described regulator for constituting by microcomputer, it comprises: a comparer, be used for the current concentration that records of moving-blade consistency transmitter is compared with setting concentration, obtain the deviate e of concentration, a differentiator, differential is carried out in variation in several sampling periods to deviate e, obtains deviation variation rate ec; The discretize unit changes continually varying variable e and ec into the discrete variable of segmentation; Taxon according to the variable e of discretize and the variation range of ec, is included into it set that N fuzzy subset forms respectively, and N=6-10 finishes the fuzzification process of two variablees; Fuzzy relation matrix unit, its input quantity are e and the ec after the obfuscation, output quantity be in the fuzzy relation matrix row with row respectively with obfuscation after e and the corresponding matrix data of ec, matrix data according to the experiment or formula insert in advance; Pulse-width modulation PWM able to programme unit is used for converting described fuzzy relation matrix unit output quantity to dutycycle variable square-wave signal and exports as Fuzzy Controller;

(2) the Fuzzy Controller output signal is added to two solid-state relay input ends respectively, and the solid-state relay output loop connects the electrically operated valve motor and realizes itself and being communicated with or shutoff of power supply.

Described concentration becomes send regulating device, and it is further characterized in that the set that described N fuzzy subset forms, and when N=8, is { negative big, negative in, bear little, negative zero, positive zero, just little, center, honest }; When N=7, be { in negative big, negative, negative little, zero, just little, center, honest }.

The present invention has following advantage:

(1) fuzzy logic control is the control method of fuzzy language type; Do not need to know in advance structure, the parameter of controlled device, do not need to set up the mathematical models of controlled device.Therefore, in consistency transmitter, embed the fuzzy controller of two inputs, single output type, regulate directly formation density Adjusting System (not needing regulator in addition) in order to replace traditional PID; Solved the bad problem of all-purpose controller PID control effect;

(2) at the characteristics of electrically operated valve, pulsewidth sequence between the control of regulator is output as for the moment; No matter open or close valve, size and polarity according to poor (deviation) of concentration measurement and concentration set point, the dutycycle of regulator output signal is different, the open terminal or the close terminal of by-pass valve control are different turn-on time, make valve event by a series of short time the time stop combination of actions when moving and form; Realized the direct control of electrically operated valve, i.e. the direct control of valve driving machine;

(3) adopt the isolating converter spare of solid-state relay as light current control forceful electric power.Solid-state relay does not have moving part (contactless), the noiseless no-spark, and Control current is little, isolates with forceful electric power, quick action, highly reliable, the long-life;

(4) save regulator and valve servo amplifier two parts hardware, both reduced cost, improved reliability again;

(5) control system overshoot is little, and response is fast; Installation line and maintenance workload have been reduced.

Description of drawings

Fig. 1 is a moving-blade consistency transmitter block diagram;

Fig. 2 is the concentration varitrol synoptic diagram of existing use;

Fig. 3 is for utilizing control system synoptic diagram of the present invention;

Fig. 4 send the adjustment system block diagram for concentration of the present invention becomes;

Fig. 5 is Fuzzy Controller system chart among the present invention;

Fig. 6 is solid-state relay and valve driving machine connecting circuit schematic diagram among the present invention;

Fig. 7 controls the output time pulse sequence diagram for the present invention;

Fig. 8 controls the effect synoptic diagram for the present invention.

Embodiment

Among Fig. 3, the real-time measurement values of moving-blade consistency transmitter P is sent into the microcomputer Fuzzy Controller, and Fuzzy Controller is exported through valve driving machine regulating and controlling valve FW aperture, and sample cock FS is used for instrument is carried out the timing signal sampling among the figure.

Below specify the constructive method of described Fuzzy Controller.

1, the linguistic variable of controller

Input variable of fuzzy controller (often getting deviation and deviation variation rate) and output variable (often getting controlled quentity controlled variable) all provide with the natural language form, rather than the numerical value form provides, and it belongs to linguistic variable.The word set of getting linguistic variable usually is the set that following 7 fuzzy subsets form:

Negative big, and negative little in bearing, negative zero, positive zero, just little, the center, honest

Represent with symbol to be exactly:

{NB，NM，NS，NO，PO，PS，PM，PB}??????(1)

2, the discretize of continuous variable

The basic domain that the actual change scope of the actual range collection output variable of input variable of fuzzy controller deviation, deviation variation rate is called these variablees.

If the basic domain of deviation E (e) is [x _e, x _e], the amount in it is accurately to measure.The quantification domain of deviation is:

X＝{-n，-n+1，…，0，…，n-1，n}??????(2)

Positive integer n is with 0～x _eThe progression that is divided into after the continually varying deviation discretize in the scope (or quantification).The quantizing factor k of deviation _eBe defined as

$K_e\stackrel{\mathrm{\Δ}}{=}n/x_e----\left(3\right)$

Quantizing factor k _eSelected back (being the selected back of n), any deviation of system always can be quantified as a certain element on the domain (2) by formula (3).Actual practice is often got n=6, and the scope of observed quantity deviation e is quantized to:

{-6，-5，-4，-3，-2，-1，0，1，2，3，4，5，6}????(4)

If deviation is got the amount on [a, b], available following discretize formula is quantized to the quantification domain with it:

$x=\mathrm{INT}\left(\frac{2n}{b-a}(x^{\text{'}}-\frac{a+b}{2})\right)----\left(5\right)$

In the formula: x ' ∈ [a, b], x ∈ X

3, the fuzzy subset of definitional language variable

After the continuous variable discretize, just it to be ranged some fuzzy subsets.As get n=6, quantize normal following the following the example of of fuzzy subset on the domain:

Negative big (NB)---get near-6

In negative (NM)---get near-4

Negative little (NS)---get near-2

Negative zero (NO)---get than near the zero point slightly

Positive zero (PO)---get than zero a little bigger slightly near

Just little (PS)---get+2 near

The center (PM)---get+4 near

Honest (PB)---get+6 near

4, fuzzy control rule

Can make control rule tables by the experience of manual strategy summary or by a large amount of test figures, control rule tables is one group of the control strategy set of describing with fuzzy language, i.e. " IF THEN

".For the fuzzy control of many inputs, can merge and simplify rule.

5, fuzzy judgment

What drawn by FUZZY ALGORITHMS FOR CONTROL is fuzzy set on the domain, but controlled device can only be accepted accurate controlled quentity controlled variable, and the fuzzy judgment that this just need carry out output information promptly is converted into accurate amount to fuzzy quantity.What be commonly used to carry out fuzzy judgment has a maximum membership degree method, method of weighted mean and get median method.Consider the characteristic of controlled device, we have selected the maximum membership degree method, and its advantage is simple, and is easy to use, and the algorithm real-time is good.

6, illustrate

In the microcomputer concentration transporting regulator of the single output type of two inputs, according to E, the basic domain of EC utilizes quantizing factor k _e, k _EcCarry out fuzzy quantization.And the basic domain of definite U and quantification domain.

Input quantity 1: pulp density deviation e

The basic domain of setting the pulp density deviation is :-0.8%～0.8% pulp density;

Get quantizing factor k _e=6/x _e, get by formula (4) formula and to quantize domain and be:

X＝{-6，-5，-4，-3，-2，-1，-0，+0，1，2，3，4，5，6}

Then basic domain is quantized to one by one and is quantized in the domain by discretize formula (5-5):

-6：-0.8％≤e＜-0.74％

-5：-0.74％≤e＜-0.6％

-4：-0.6≤e＜-0.47％

-3：-0.47％≤e＜-0.34％

-2：-0.34％≤e＜-0.2％

-1：-0.2％≤e＜-0.07％

0：-0.07％≤e＜0.07％

1：0.07％≤e＜0.2％

2：0.2％≤e＜0.34％

3：0.34％≤e＜0.47％

4：0.47％≤e＜0.6％

5：0.6％≤e＜0.74％

6：0.74％≤e＜0.8％

Select word set to be by formula (1):

{NB _e，NM _e，NS _e，NO _e，PO _e，PS _e，PM _e，PB _e}

Then the degree of membership of each word set is:

NB _e＝1.0/-6+0.8/-5+0.4/-4+0.1/-3，

NM _e＝0.2/-6+0.7/-5+1.0/-4+0.7/-3+0.2/-2，

NS _e＝0.1/-4+0.5/-3+1.0/-2+0.8/-1+0.3/-0，

NO _e＝0.1/-2+0.6/-1+1.0/-0，

PO _e＝1.0/+0+0.6/1+0.1/2，

PS _e＝0.3/+0+0.8/1+1.0/2+0.5/3+0.1/4，

PM _e＝0.2/2+0.7/3+1.0/4+0.7/5+0.2/6，

PB _e＝0.1/3+0.4/4+0.8/5+1.0/6，

Input quantity 2: pulp density deviation variation rate ec

The basic domain of setting the pulp density deviation variation rate is :-0.5%～0.5% pulp density;

Get quantizing factor k _Ec=6/x _e, get by formula (4) and to quantize domain and be:

X＝{-6，-5，-4，-3，-2，-1，0，?1，2，?3，4，5，6}

Then basic domain is quantized to one by one and is quantized in the domain by discretize formula (5):

-6：-0.5％≤e＜-0.46％

-5：-0.46％≤e＜-0.38％

-4：-0.38≤e＜-0.3％

-3：-0.3％≤e＜-0.2％

-2：-0.2％≤e＜-0.13％

-1：-0.13％≤e＜-0.04％

0：-0.04％≤e＜0.04％

1：0.04％≤e＜0.13％

2：0.13％≤e＜0.2％

3：0.2％≤e＜0.3％

4：0.3％≤e＜0.38％

5：0.38％≤e＜0.46％

6：0.46％≤e＜0.5％

Select word set to be by formula (1):

{NB _ec，NM _ec，NS _ec，ZO _ec，PS _ec，PM _ec，PB _ec}

Then the degree of membership of each word set is:

NB _ec＝1.0/-6+0.8/-5+0.4/-4+0.1/-3，

NM _ec＝0.2/-6+0.7/-5+1.0/-4+0.7/-3+0.2/-2，

NS _ec＝0.2/-4+0.7/-3+1.0/-2+0.9/-1，

ZO _ec＝0.5/-1+1.0/0+0.5/1，

PS _ec＝0.9/1+1.0/2+0.7/3+0.2/4，

PM _ec＝0.2/2+0.7/3+1.0/4+0.7/5+0.2/6，

PB _ec＝0.1/3+0.4/4+0.8/5+1.0/6，

Output quantity: valve opening gets increment u

The basic domain that the setting valve opening gets increment is :-12～12 (control PWM gets increment);

Get the scale factor k of output controlled quentity controlled variable _u=u/7, output quantity quantizes domain and is:

X＝{-7，-6，-5，-4，-3，-2，-1，0，1，2，3，4，5，6，7}

Then basic domain is quantized to one by one and is quantized in the domain by discretize formula (3-5):

-7：{-12，-11}

-6：{-10，-9}

-5：{-8，-7}

-4：{-6，}

-3：{-5，-4}

-2：{-3，-2}

-1：{-1}

0：{0}

1：{1}

2：{3，2}

3：{5，4}

4：{6，}

5：{8，7}

6：{10，9}

7：{12，11}

Select word set to be by formula (1):

{NB _u，NM _u，NS _u，ZO _u，PS _u，PM _u，PB _u}

Then the degree of membership of each word set is:

NB _u＝1.0/-7+0.8/-6+0.4/-5+0.1/-4，

NM _u＝0.2/-6+0.7/-5+1.0/-4+0.7/-3+0.2/-2，

NS _u＝0.1/-4+0.4/-3+0.8/-2+1.0/-1+0.4/0，

ZO _u＝0.5/-1+1.0/0+0.5/1，

PS _u＝0.4/0+1.0/1+0.8/2+0.4/3+0.1/4，

PM _u＝0.2/2+0.7/3+1.0/4+0.7/5+0.2/6，

PB _u＝0.1/4+0.4/5+0.8/6+1.0/7，

Because system is the output of dual input list, adopt the rule of " if A and B then C ", sum up operator's practical experience, obtain the language control rule tables, see Table 1.In table, have 56 control laws, represent respectively under different condition, should take control strategy.

Table 1 fuzzy control rule table

These 56 rules can be merged into 21 rules by the following method:

As: IF NB _eAND NB _EcTHEN PB _u

IF??NM _e?AND??NB _ec?THEN??PB _u

IF??NB _e?AND??NM _ec?THEN??PB _u

IF??NM _e?AND??NM _ec?THEN??PB _u

These four rules can be merged into rule:

IF?NB _e?OR?NM _e?AND?NB _ec?OR?NM _ec?THEN?PB _u

According to the dual input fuzzy condition statement " if

And

Then

", every rule is obtained its fuzzy relation R _i

$R_i={(A\×B)}^{T_1}\·C----\left(6\right)$

Behind actual measurement e and ec, through quantizing factor k _e, k _EcBut fuzzy quantization is the single-point fuzzy set, E, EC; Reach according to formula (6):

U _i＝(E×EC)·R _i?????????????(7)

To 21 rules of control law, obtain 21 fuzzy control quantities respectively, be designated as U successively ₁, U ₂.U ₂₁, so total fuzzy control quantity is:

U＝U ₁∪U ₂∪U ₃∪…∪U ₂₁??????(8)

Carry out fuzzy judgment with the maximum membership degree method, last accurate amount u that just can controlled output quantity.

All over the various possibility situations of getting the input data, carry out above-mentioned computing, obtain every kind of pairing output quantity of input, be compiled into fuzzy control table.More than work and to finish by off-line, then fuzzy control table is deposited in the computing machine as " file ", see Table 2.

For overcome ordinary fuzzy controller input, output variable be quantified as the limited control accuracy that discrete value caused low with the stable state flutter problem that may occur, utilize the successive value of fuzzy control table and input, the two interpolation algorithms of employing binary function burst on rectangular domain online calculate the controlled quentity controlled variable of continuous variable, can significantly improve control accuracy.

Therefore, in that control algolithm is in the cycle every time a step, e and ec that sampling is obtained use quantizing factor k respectively _e, k _EcConvert continuous E to _iAnd EC _iAnd without rounding operation.

E _i＝K _e·e；EC _i＝K _ec·ec，E _i，EC _i∈[-6，6]。

Interpolation arithmetic is carried out in control table obtain continuous U (K _eE, K _EcEc), again through K _uDraw the output controlled quentity controlled variable after the weighting:

u＝INT(K _u·U)，U∈[-7，7]，

The output controlled quentity controlled variable is converted into the variable square-wave signal of dutycycle, the increase and decrease of by-pass valve control aperture via pwm unit PWM again.

	??-6	??-5	??-4	??-3	??-2	??-1	??-0	??+0	??1	??2	??3	??4	??5	??6
															-6	??7	??6	??7	??7	??4	??4	??4	??4	??2	??1	??0	??0	??0	??0
-5	??6	??6	??6	??6	??4	??4	??4	??4	??2	??2	??0	??0	??0	??0
															-4	??7	??6	??7	??6	??4	??4	??4	??4	??2	??1	??0	??0	??0	??0
-3	??6	??6	??6	??6	??5	??5	??5	??5	??2	??2	??0	??-2	??-2	??-2
															-2	??7	??6	??7	??6	??4	??4	??1	??1	??0	??0	??-3	??-4	??-4	??-4
-1	??7	??6	??7	??6	??4	??4	??1	??1	??0	??-3	??-3	??-4	??-4	??-4
															0	??7	??6	??7	??6	??4	??1	??0	??0	??-1	??-4	??-6	??-7	??-6	??-7
1	??4	??4	??4	??3	??1	??0	??-1	??-1	??-4	??-4	??-6	??-7	??-6	??-7
															2	??4	??4	??4	??2	??0	??0	??-1	??-1	??-4	??-4	??-6	??-7	??-6	??-7
3	??2	??2	??2	??0	??0	??0	??-1	??-1	??-3	??-3	??-6	??-6	??-6	??-6
															4	??0	??0	??0	??-1	??-1	??-3	??-4	??-4	??-4	??-4	??-6	??-7	??-6	??-7
5	??0	??0	??0	??-1	??-1	??-2	??-4	??-4	??-4	??-4	??-6	??-6	??-6	??-6
															6	??0	??0	??0	??-1	??-1	??-1	??-4	??-4	??-4	??-4	??-6	??-7	??-6	??-7

Table 2 fuzzy control table

Fig. 7 represents to control the output time pulse sequence diagram, and the dutycycle of regulator output signal is different, and the open terminal or the close terminal of by-pass valve control are different turn-on time, stops combination of actions when moving when making valve event by a series of short time and forms.

Fig. 8 represents text invention control effect, and fuzzy overshoot of regulating is little, and response speed is fast.

Claims (2)

1, regulating device is sent in the concentration change, comprise moving-blade consistency transmitter, regulator, valve driving machine and variable valve, connected by electric signal in regular turn between them, described moving-blade consistency transmitter comprises sensitive element, leverage, photoelectric sensor and forcer, it is characterized in that:

(1) Fuzzy Controller of described regulator for constituting by microcomputer, it comprises:

A comparer is used for the current concentration that records of moving-blade consistency transmitter is compared with setting concentration, obtains the deviate e of concentration;

A differentiator, differential is carried out in the variation in several sampling periods to deviate e, obtains deviation variation rate ec; The discretize unit changes continually varying variable e and ec into the discrete variable of segmentation;

Taxon according to the variable e of discretize and the variation range of ec, is included into it set that N fuzzy subset forms respectively, and N=6-10 finishes the fuzzification process of two variablees; Fuzzy relation matrix unit, its input quantity are e and the ec after the obfuscation, output quantity be in the fuzzy relation matrix row and row respectively with obfuscation after e and the corresponding matrix data of ec, matrix data insert in advance according to experiment or formula;

Pulse-width modulation PWM able to programme unit is used for converting described fuzzy relation matrix unit output quantity to dutycycle variable square-wave signal and exports as Fuzzy Controller;

(2) the Fuzzy Controller output signal is added to two solid-state relay input ends respectively, and the solid-state relay output loop connects the electrically operated valve motor and realizes itself and being communicated with or shutoff of power supply.

2, concentration as claimed in claim 1 becomes and send regulating device, it is characterized in that the set that described N fuzzy subset forms, and when N=8, is { negative big, negative in, bear little, negative zero, positive zero, just little, center, honest }; When N=7, be { in negative big, negative, negative little, zero, just little, center, honest }.

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