CN103245481A - Frequency conversion technology based detection method for air resistance characteristic of large-scale variable-load heat exchanger - Google Patents
Frequency conversion technology based detection method for air resistance characteristic of large-scale variable-load heat exchanger Download PDFInfo
- Publication number
- CN103245481A CN103245481A CN2013101644232A CN201310164423A CN103245481A CN 103245481 A CN103245481 A CN 103245481A CN 2013101644232 A CN2013101644232 A CN 2013101644232A CN 201310164423 A CN201310164423 A CN 201310164423A CN 103245481 A CN103245481 A CN 103245481A
- Authority
- CN
- China
- Prior art keywords
- frequency
- output
- air quantity
- value
- input
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Feedback Control In General (AREA)
Abstract
The invention discloses a frequency conversion technology based detection method for the air resistance characteristic of a large-scale variable-load heat exchanger. The method comprises the specific steps: speculating an initial frequency predicted value f0 of a frequency converter under standard wind volume according to history data in combination with a nerve network; calculating out three parameters K, T and t of an open-loop transfer function(as shown in the specification) between frequency converter frequency and the pipeline wind volume through a least squares algorithm through acquiring the wind volume and frequency variations of the frequency converter with frequency changing from 0 to f0; then taking IATE as an optimal index and PID+(as shown in the specification) as the open-loop transfer function, utilizing the a closed-loop transfer function as a restraint equation, and performing optimization solution by a nonlinear optimization solver to obtain optimal values Kji, Ti and Td of a PID controller; and obtaining a corrected frequency value f'0 according to approximate linear feature of the wind volume and the frequency at the working point, and regulating the frequency of the frequency converter to f'0. According to the invention, the detection method avoids troubles brought by manually adjusting wind volume, is energy-saving and time-saving, is convenient and quick, and effectively improves the production efficiency.
Description
Technical field
The invention belongs to the control technology field, relate to data modeling and the process control in industrial process control field, relate in particular to a kind of detection method of the varying load large heat exchanger vapour lock characteristic based on converter technique.
Background technology
The vapour lock characteristic is the important indicator that characterizes the large heat exchanger flowing property, also is one of important indicator of large-scale plate type finned heat exchanger product necessary test before dispatching from the factory.Mainly comprise two aspects: one is for certain heat exchanger channel, under standard temperature, normal pressure and normal flow situation, and the pressure loss at these heat exchanger channel two ends; Another one is the friction factor of heat exchanger channel in the case.Because test result difference under conditions such as different temperatures, pressure lacks comparability.Therefore the required standard situation is that a normal atmosphere is depressed, the standard zero degrees celsius is the status of criterion, and the air quantity that record this moment is the standard air quantity, and the air quantity that records under other pressure and temperatures need be converted into the standard air quantity.Past, the general orifice flowmeter that adopts was by measuring the vapour lock parameter of heat interchanger under certain air quantity situation in measuring process, and converting then obtains the vapour lock characteristic of heat interchanger under normal conditions.Adopt above method to have significant disadvantages, one is that the measurement accuracy of orifice flowmeter is poor, the mode of manual control valve is adopted in the control of air quantity in addition, cannot accurately control the air quantity after conversion, the 3rd is that the measurement of employing orifice plate and not energy-conservation, inaccurate, the follow-up artificial calculated amount of manual control are big, because each heat interchanger test duration is long, work efficiency is lower.
Adopt the air quantity of Frequency Converter Control blower fan, adopt the nozzle measuring system can the resolution system power saving, the precision that nozzle is measured air quantity be much higher than orifice flowmeter.Owing to can't guarantee that current working is in standard condition in the test process, need the temperature and pressure of heat exchanging device to convert according to the equation of gas state, conversion method is:
, here
With
The expression standard temperature and pressure (STP),
Be the actual measurement air quantity,
With
Be observed pressure and temperature,
Then be the standard air quantity after converting.For the purpose of accurately, with the standard air quantity of the quick control of air quantity after conversion, requirement just will be surveyed air quantity by converting the standard air quantity to, control this standard air quantity then and make it equal to set air quantity in heat exchanger channel performance test process.Consider efficient and the energy-conservation requirement of test, measurement mechanism adopts converter technique to carry out air quantity and regulates.
It is that test has intermittence that the different lane testings of heat interchanger also have characteristics: after namely testing a passage, before new passage was received measurement mechanism, it was zero that measurement mechanism air channel air quantity requires.Because the model of each heat interchanger is different with type, in test process, how to determine the original frequency of frequency converter, and how according to the characteristic of system under test (SUT), adopt suitable control method that air quantity is stablized control on the setting value corresponding with standard condition, heat exchanging device measuring accuracy and rapidity have material impact.Because the nonlinear characteristic that hysteresis quality, the different passage part throttle characteristics of measuring system are widely different and frequency variation signal changes causes system to be difficult to realize measuring fast automatically.Therefore be necessary to study a kind of method of observing and controlling air quantity fast that can realize in the case automatically, make it to satisfy the industrial requirements of plate type finned heat exchanger vapour lock characteristic test.
Summary of the invention
The objective of the invention is at the deficiencies in the prior art, a kind of detection method of the varying load large heat exchanger vapour lock characteristic based on converter technique is provided.
The technical solution used in the present invention is as follows:
Step (1) is gathered dissimilar plate type finned heat exchanger design parameters and operational factor, sets up the real-time data base that comprises design of heat exchanger parameter and operational factor, and the collection of concrete parameter is obtained by the database in the heat exchanger system detection platform.
Described design of heat exchanger parameter comprises tunnel name, design air flow, the design vapour lock of heat interchanger, and operational factor comprises actual vapour lock, detected temperatures, air pressure and the actual frequency converter frequency of heat interchanger, and the preparation method of these parameters is mature technology.
Based on historical test data, the employing neural network is set up the neural network model between design standards air quantity, design vapour lock and actual vapour lock, the actual frequency converter frequency, predict that with this blower fan is in order to reach the original frequency predicted value of this air quantity under various heat exchange device channels designs standard air quantity
, concrete implementation step is as follows:
At first, extract the historical data under each heat exchanger channel situation, set up input sample and output sample collection, the input sample comprises design air flow, design vapour lock, the detected temperatures of heat interchanger, output sample is that actual vapour lock and heat interchanger are at the actual frequency converter frequency that reaches under the design air flow, adopt neural network that these historical datas are trained then, neural network structure comprises input layer, hidden layer (middle layer) and output layer, and the neuron number scope of hidden layer and output layer is respectively 4~10 and 2~6.In the training process with design air flow, design vapour lock and detected temperatures as input, as output, obtain neural network model by neural network learning with actual frequency converter frequency and actual vapour lock, each parameter-definition in the neural network model is as follows:
Input layer unit input vector is
, object vector
Hidden layer unit input vector
, output vector
The output layer unit input vector
, output vector
, k=1,2 ..., m represents the sample data number; Input layer is to the connection weight of hidden layer
, i=1,2 ...., n; J=1,2 ... p; Hidden layer is to the connection weight of output layer
, t=1,2 ... q; The output threshold value of each unit of hidden layer
, the output threshold value of each unit of output layer
The learning process step of neural network model is as follows:
A) connection weights and the threshold value of each layer of initialization are given each connection weight
,
With the output threshold value
,
Give the random value in the interval (1,1).
B) choose input sample and output sample.
C) with the output of importing sample, connection weight, input threshold value and output threshold calculations hidden layer and each unit of output layer.
Wherein,
The input value of expression hidden layer unit,
The output valve of expression hidden layer unit,
The input value of expression output layer unit,
The output valve of expression output layer unit.
D) calculate each unit vague generalization error of output layer
, utilize hidden layer to the connection weight of output layer then
, hidden layer output vector
, each unit vague generalization error of output layer
Calculate the vague generalization error of each unit of hidden layer
, computing formula is as follows:
;
E) utilize the vague generalization error of each unit of output layer
Revise hidden layer to the connection weight of output layer with the output valve of each unit of hidden layer
, output threshold value
:
Utilize the vague generalization error of each unit of hidden layer equally
Revise input layer to the connection weight of hidden layer with the input of input layer
, output threshold value
:
Represent current connection weight
,
Represent revised connection weight;
Represent current output threshold value
,
Represent revised respective threshold.
Represent current connection weight
,
Represent revised connection weight,
Represent current threshold value,
Represent revised threshold value, N=1,2 ..., NN, wherein NN represents the study iterations set.
F) choose next input sample and output sample, turn back to step c), finish up to m training sample training.
G) calculate the cumulative errors of all samples
, the cumulative errors account form is
, wherein, q represents the output layer unit number, m represents sample size.If sample cumulative errors
Less than preset value
, perhaps current study iterations is greater than the study iterations of setting, and learning training finishes so.Otherwise choose sample input and target output again, turn back to step c) then.
After learning process finishes, weights and threshold value by the neural network each several part that obtains, foundation can reflect the neural network model of input and output, by given input information (design air flow, design vapour lock and detected temperatures), obtains the predicted value of frequency converter original frequency.
Step (2): according to design air flow, design vapour lock and the detected temperatures of real exchanger passage, the neural network model that utilizes step (1) to set up obtains the original frequency predicted value of this heat interchanger channel condition low-converter
Step (3): the original frequency predicted value that obtains according to step (2)
, the blower fan frequency is adjusted to from 0
80%, be designated as
, when the blower fan frequency reaches
And behind stable operation 10~20s, record and survey the standard air quantity and be designated as this moment
With the blower fan frequency adjustment be
100%, be designated as
, when the blower fan frequency reaches
And after stablizing 10~20s, record and survey the standard air quantity and be designated as this moment
And the blower fan frequency to
And stablize in 10~20s process, with actual measurement standard air quantity, actual measurement vapour lock and the blower fan frequency of cycle 0.5~1s record heat exchanger channel, then, actual measurement standard air quantity and blower fan frequency that record in this process is obtained deduct respectively
With
, obtain the air quantity changing value
, the frequency change value
, wherein
With
Respectively the of expression record
Individual air quantity changes and the frequency change value.
Step (4): according to the mobile control of pipeline gas model feature, set up the transport function between frequency and the air quantity.The air quantity control system transport function is that one order inertia adds delay link, therefore the transport function between frequency and the standard air quantity can be made as
, wherein
Represent open loop enlargement factor, time constant and time delay respectively,
Be plural number.The frequency change value that obtains according to step (3)
, will
Give positive initial value respectively, pass through transport function
Calculate in sample point frequency change value
Output under the effect
, then with
Be target, the employing least-squares algorithm simulates three parameters in the transport function
, obtain the concrete transport function of this heat interchanger passage.
Step (5): set up the concrete transport function of heat interchanger passage in step (4) after, air quantity is adjusted to preset standard air quantity, the parameter of the PID that adjusts in order to ensure fast and stable.Be optimum index with IATE integration performance, with parameter in the PID controller
,
,
Be variable, with PID+
As open-loop transfer function, be equation of constraint with the closed loop transfer function,, with
,
,
Be on the occasion of being variable bound, adopt the nonlinear optimization solution technique to be optimized and find the solution, obtain optimum PID controller parameter
,
,
Value, wherein
,
,
Represent ratio, integration and differential parameter respectively.
Step (6): obtain the original frequency predicted value according to step (2)
And the frequency that obtains of step (3)
, calculate approximate linear parameter between air quantity and the frequency, and the modified value of definite original frequency
, with the blower fan frequency adjustment to modified value
, and stable
Second.According to the principle of similitude, frequency
With air quantity
Exist approximation relation to be
, wherein
With
The linear relationship parameter that obtains for needs.With the original frequency predicted value
With
And corresponding air quantity, bring above relational expression into and obtain parameter
With
Obtaining
With
After, according to
Relation, the order
Be the established standards air quantity, obtain the modified value of original frequency under the established standards air quantity
Step (7): the blower fan frequency setting is existed
Frequency point, equifrequent reach setting value and stable
After second.Adopt the increment type PID controller that the actual measurement air quantity of heat exchanger channel is controlled at established standards air quantity place then, obtain the vapour lock characteristic of heat exchanger channel under the established standards air quantity.The output form of PID is:
;
Here three of the increment type PID controller parameters
,
,
For obtain in step (5) those three parameters.
The expression sampling period,
Represent the setting value of corresponding step number and the error between the value of feedback,
,
,
Represent current frequency values, frequency change value and next step frequency values respectively.By increment type PID control, the actual measurement airflow value can be controlled automatically in the established standards airflow value, control accuracy is in 0.5%.Be exactly vapour lock characteristic under established standards air quantity by the vapour lock characteristic that measures this moment, and the comparison by between actual measurement vapour lock and the design vapour lock can get heat interchanger vapour lock characteristic performance index.
Beneficial effect of the present invention:
The present invention not only replaces manual inspection heat interchanger vapour lock characteristic method in the past fully, has automatic detection, calculates and characteristic of high test precision automatically.Robotization and the rapidity of this method are very good, can adapt to different loads and air quantity requirement, when improving measuring accuracy, reducing labor workload, can accelerate heat interchanger test lot number greatly.
Embodiment
Based on the detection method of the varying load large heat exchanger vapour lock characteristic of converter technique, to the different channel characteristics of various heat exchange device, carry out measuring fast automatically the vapour lock characteristic.The present invention at first carries out data mining according to historical test data, the employing neural network is set up the relation between design of heat exchanger parameter and the original frequency, obtain the control characteristic of heat exchanger channel then by the automatic identification of the control characteristic parameter of various heat exchange device passage, adopt the adjust pid parameter of self-actuated controller of optimal performance index, standard value after adopting the increment type PID controller with the conversion of air channel air quantity then controls to established standards air quantity place, obtains its vapour lock characteristic by the vapour lock value that detects this moment.
Concrete steps of the present invention are as follows:
Step (1) is gathered dissimilar plate type finned heat exchanger design parameters and operational factor, sets up the real-time data base that comprises design of heat exchanger parameter and operational factor, and the collection of concrete parameter is obtained by the database in the heat exchanger system detection platform.
Described design of heat exchanger parameter comprises tunnel name, design air flow, the design vapour lock of heat interchanger, and operational factor comprises actual vapour lock, detected temperatures, air pressure and the actual frequency converter frequency of heat interchanger, and the preparation method of these parameters is mature technology.
Based on historical test data, the employing neural network is set up the neural network model between design standards air quantity, design vapour lock and actual vapour lock, the actual frequency converter frequency, predict that with this blower fan is in order to reach the original frequency predicted value of this air quantity under various heat exchange device channels designs standard air quantity
, concrete implementation step is as follows:
At first, extract the historical data under each heat exchanger channel situation, set up input sample and output sample collection, the input sample comprises design air flow, design vapour lock, the detected temperatures of heat interchanger, output sample is that actual vapour lock and heat interchanger are at the actual frequency converter frequency that reaches under the design air flow, adopt neural network that these historical datas are trained then, neural network structure comprises input layer, hidden layer (middle layer) and output layer, and the neuron number scope of hidden layer and output layer is respectively 4~10 and 2~6.In the training process with design air flow, design vapour lock and detected temperatures as input, as output, obtain neural network model by neural network learning with actual frequency converter frequency and actual vapour lock, each parameter-definition in the neural network model is as follows:
Input layer unit input vector is
, object vector
Hidden layer unit input vector
, output vector
The output layer unit input vector
, output vector
, k=1,2 ..., m represents the sample data number; Input layer is to the connection weight of hidden layer
, i=1,2 ...., n; J=1,2 ... p; Hidden layer is to the connection weight of output layer
, t=1,2 ... q; The output threshold value of each unit of hidden layer
, the output threshold value of each unit of output layer
The learning process step of neural network model is as follows:
H) connection weights and the threshold value of each layer of initialization are given each connection weight
,
With the output threshold value
,
Give the random value in the interval (1,1).
I) choose input sample and output sample.
J) with the output of importing sample, connection weight, input threshold value and output threshold calculations hidden layer and each unit of output layer.
Wherein,
The input value of expression hidden layer unit,
The output valve of expression hidden layer unit,
The input value of expression output layer unit,
The output valve of expression output layer unit.
K) calculate each unit vague generalization error of output layer
, utilize hidden layer to the connection weight of output layer then
, hidden layer output vector
, each unit vague generalization error of output layer
Calculate the vague generalization error of each unit of hidden layer
, computing formula is as follows:
;
L) utilize the vague generalization error of each unit of output layer
Revise hidden layer to the connection weight of output layer with the output valve of each unit of hidden layer
, output threshold value
:
Utilize the vague generalization error of each unit of hidden layer equally
Revise input layer to the connection weight of hidden layer with the input of input layer
, output threshold value
:
Represent current connection weight
,
Represent revised connection weight;
Represent current output threshold value
,
Represent revised respective threshold.
Represent current connection weight
,
Represent revised connection weight,
Represent current threshold value,
Represent revised threshold value, N=1,2 ..., NN, wherein NN represents the study iterations set.
M) choose next input sample and output sample, turn back to step c), finish up to m training sample training.
N) calculate the cumulative errors of all samples
, the cumulative errors account form is
, wherein, q represents the output layer unit number, m represents sample size.If sample cumulative errors
Less than preset value
, perhaps current study iterations is greater than the study iterations of setting, and learning training finishes so.Otherwise choose sample input and target output again, turn back to step c) then.
After learning process finishes, weights and threshold value by the neural network each several part that obtains, foundation can reflect the neural network model of input and output, by given input information (design air flow, design vapour lock and detected temperatures), obtains the predicted value of frequency converter original frequency.
Step (2): according to design air flow, design vapour lock and the detected temperatures of real exchanger passage, the neural network model that utilizes step (1) to set up obtains the original frequency predicted value of this heat interchanger channel condition low-converter
Step (3): the original frequency predicted value that obtains according to step (2)
, the blower fan frequency is adjusted to from 0
80%, be designated as
, when the blower fan frequency reaches
And behind stable operation 10~20s, record and survey the standard air quantity and be designated as this moment
With the blower fan frequency adjustment be
100%, be designated as
, when the blower fan frequency reaches
And after stablizing 10~20s, record and survey the standard air quantity and be designated as this moment
And the blower fan frequency from
Arrive
And stablize in 10~20s process, with actual measurement standard air quantity, actual measurement vapour lock and the blower fan frequency of cycle 0.5~1s record heat exchanger channel, then, actual measurement standard air quantity and blower fan frequency that record in this process is obtained deduct respectively
With
, obtain the air quantity changing value
, the frequency change value
, wherein
With
Respectively the of expression record
Individual air quantity changes and the frequency change value.
Step (4): according to the mobile control of pipeline gas model feature, set up the transport function between frequency and the air quantity.The air quantity control system transport function is that one order inertia adds delay link, therefore the transport function between frequency and the standard air quantity can be made as
, wherein
Represent open loop enlargement factor, time constant and time delay respectively,
Be plural number.The frequency change value that obtains according to step (3)
, will
Give positive initial value respectively, pass through transport function
Calculate in sample point frequency change value
Output under the effect
, then with
Be target, the employing least-squares algorithm simulates three parameters in the transport function
, obtain the concrete transport function of this heat interchanger passage.
Step (5): set up the concrete transport function of heat interchanger passage in step (4) after, air quantity is adjusted to preset standard air quantity, the parameter of the PID that adjusts in order to ensure fast and stable.Be optimum index with IATE integration performance, with parameter in the PID controller
,
,
Be variable, with PID+
As open-loop transfer function, be equation of constraint with the closed loop transfer function,, with
,
,
Be on the occasion of being variable bound, adopt the nonlinear optimization solution technique to be optimized and find the solution, obtain optimum PID controller parameter
,
,
Value, wherein
,
,
Represent ratio, integration and differential parameter respectively.
Step (6): obtain the original frequency predicted value according to step (2)
And the frequency that obtains of step (3)
, calculate approximate linear parameter between air quantity and the frequency, and the modified value of definite original frequency
, with the blower fan frequency adjustment to modified value
, and stable
Second.According to the principle of similitude, frequency
With air quantity
Exist approximation relation to be
, wherein
With
The linear relationship parameter that obtains for needs.With the original frequency predicted value
With
And corresponding air quantity, bring above relational expression into and obtain parameter
With
Obtaining
With
After, according to
Relation, the order
Be the established standards air quantity, obtain the modified value of original frequency under the established standards air quantity
Step (7): the blower fan frequency setting is existed
Frequency point, equifrequent reach setting value and stable
After second.Adopt the increment type PID controller that the actual measurement air quantity of heat exchanger channel is controlled at established standards air quantity place then, obtain the vapour lock characteristic of heat exchanger channel under the established standards air quantity.The output form of PID is:
Here three of the increment type PID controller parameters
,
,
For obtain in step (5) those three parameters.
The expression sampling period,
Represent the setting value of corresponding step number and the error between the value of feedback,
,
,
Represent current frequency values, frequency change value and next step frequency values respectively.By increment type PID control, the actual measurement airflow value can be controlled automatically in the established standards airflow value, control accuracy is in 0.5%.Be exactly vapour lock characteristic under established standards air quantity by the vapour lock characteristic that measures this moment, and the comparison by between actual measurement vapour lock and the design vapour lock can get heat interchanger vapour lock characteristic performance index.
Claims (1)
1. based on the detection method of the varying load large heat exchanger vapour lock characteristic of converter technique, it is characterized in that this method comprises the steps:
Step (1) is gathered dissimilar plate type finned heat exchanger design parameters and operational factor, sets up the real-time data base that comprises design of heat exchanger parameter and operational factor, and the collection of concrete parameter is obtained by the database in the heat exchanger system detection platform;
Described design of heat exchanger parameter comprises tunnel name, design air flow, the design vapour lock of heat interchanger, and operational factor comprises actual vapour lock, detected temperatures, air pressure and the actual frequency converter frequency of heat interchanger;
Based on historical test data, the employing neural network is set up the neural network model between design standards air quantity, design vapour lock and actual vapour lock, the actual frequency converter frequency, predict that with this blower fan is in order to reach the original frequency predicted value of this air quantity under various heat exchange device channels designs standard air quantity
, concrete implementation step is as follows:
At first, extract the historical data under each heat exchanger channel situation, set up input sample and output sample collection, the input sample comprises design air flow, design vapour lock, the detected temperatures of heat interchanger, output sample be actual vapour lock and heat interchanger at the actual frequency converter frequency that reaches under the design air flow, adopt neural network that these historical datas are trained then; Neural network structure comprises input layer, hidden layer and output layer, and the neuron number scope of hidden layer and output layer is respectively 4~10 and 2~6; In the training process with design air flow, design vapour lock and detected temperatures as input, as output, obtain neural network model by neural network learning with actual frequency converter frequency and actual vapour lock, each parameter-definition in the neural network model is as follows:
Input layer unit input vector is
, object vector
Hidden layer unit input vector, output vector
The output layer unit input vector
, output vector
, k=1,2 ..., m represents the sample data number; Input layer is to the connection weight of hidden layer
, i=1,2 ..., n; J=1,2 ... p; Hidden layer is to the connection weight of output layer
, t=1,2 ... q; The output threshold value of each unit of hidden layer
, the output threshold value of each unit of output layer
The learning process step of neural network model is as follows:
Connection weights and the threshold value of each layer of initialization are given each connection weight
, and output threshold value
,
Give the random value in the interval (1,1);
Choose input sample and output sample;
Output with input sample, connection weight, input threshold value and output threshold calculations hidden layer and each unit of output layer;
Wherein,
The input value of expression hidden layer unit,
The output valve of expression hidden layer unit,
The input value of expression output layer unit,
The output valve of expression output layer unit;
Calculate each unit vague generalization error of output layer
, utilize hidden layer to the connection weight of output layer then
, hidden layer output vector
, each unit vague generalization error of output layer
Calculate the vague generalization error of each unit of hidden layer
, computing formula is as follows:
Utilize the vague generalization error of each unit of output layer
Revise hidden layer to the connection weight of output layer with the output valve of each unit of hidden layer
, output threshold value
:
Equally, utilize the vague generalization error of each unit of hidden layer
Revise input layer to the connection weight of hidden layer with the input of input layer
, output threshold value
:
Wherein,
Represent current connection weight
,
Represent revised connection weight;
Represent current output threshold value
,
Represent revised respective threshold;
Represent current connection weight
,
Represent revised connection weight,
Represent current threshold value,
Represent revised threshold value, N=1,2 ..., NN, wherein NN represents the study iterations set;
Choose next input sample and output sample, turn back to step c), finish up to m training sample training;
Calculate the cumulative errors of all samples
, the cumulative errors account form is
, wherein, q represents the output layer unit number, m represents sample size; If sample cumulative errors
Less than preset value
, perhaps current study iterations is greater than the study iterations of setting, and learning training finishes so; Otherwise choose sample input and target output again, turn back to step c) then;
After learning process finished, by weights and the threshold value of the neural network each several part that obtains, foundation can reflect the neural network model of input and output, by given input sample information, obtains the predicted value of frequency converter original frequency;
Step (2) is according to design air flow, design vapour lock and the detected temperatures of real exchanger passage, and the neural network model that utilizes step (1) to set up obtains the original frequency predicted value of this heat interchanger channel condition low-converter
The original frequency predicted value that step (3) obtains according to step (2)
, the blower fan frequency is adjusted to from 0
80%, be designated as
, when the blower fan frequency reaches
And behind stable operation 10~20s, record and survey the standard air quantity and be designated as this moment
With the blower fan frequency adjustment be
100%, be designated as
, when the blower fan frequency reaches
And after stablizing 10~20s, record and survey the standard air quantity and be designated as this moment
And the blower fan frequency from
Arrive
And stablize in 10~20s process, with actual measurement standard air quantity, actual measurement vapour lock and the blower fan frequency of cycle 0.5~1s record heat exchanger channel, then, actual measurement standard air quantity and blower fan frequency that record in this process is obtained deduct respectively
With
, obtain the air quantity changing value
, the frequency change value
, wherein
With
Respectively the of expression record
Individual air quantity changes and the frequency change value;
Step (4) flows according to pipeline gas and controls model feature, sets up the transport function between frequency and the air quantity; The air quantity control system transport function is that one order inertia adds delay link, therefore the transport function between frequency and the standard air quantity can be made as
, wherein
Represent open loop enlargement factor, time constant and time delay respectively,
Be plural number; The frequency change value that obtains according to step (3)
, will
Give positive initial value respectively, pass through transport function
Calculate in sample point frequency change value
Output under the effect
, then with
Be target, the employing least-squares algorithm simulates three parameters in the transport function
, obtain the concrete transport function of this heat interchanger passage;
After step (5) has been set up the concrete transport function of heat interchanger passage in step (4), air quantity is adjusted to preset standard air quantity, the parameter of the PID that adjusts in order to ensure fast and stable; Be optimum index with IATE integration performance, with parameter in the PID controller
,
,
Be variable, with PID+
As open-loop transfer function, be equation of constraint with the closed loop transfer function,, with
,
,
Be on the occasion of being variable bound, adopt the nonlinear optimization solution technique to be optimized and find the solution, obtain optimum PID controller parameter
,
,
Value, wherein
,
,
Represent ratio, integration and differential parameter respectively;
The original frequency predicted value that step (6) obtains according to step (2)
And the frequency that obtains of step (3)
, calculate approximate linear parameter between air quantity and the frequency, and the modified value of definite original frequency
, with the blower fan frequency adjustment to modified value
, and stable
Second; According to the principle of similitude, frequency
With air quantity
Exist approximation relation to be
, wherein
With
The linear relationship parameter that obtains for needs; With the original frequency predicted value
With
And corresponding air quantity, bring above relational expression into and obtain parameter
With
Obtaining
With
After, according to
Relation, the order
Be the established standards air quantity, obtain the modified value of original frequency under the established standards air quantity
Step (7) exists the blower fan frequency setting
Frequency point, equifrequent reach setting value and stable
After second; Adopt the increment type PID controller that the actual measurement air quantity of heat exchanger channel is controlled at established standards air quantity place then, obtain the vapour lock characteristic of heat exchanger channel under the established standards air quantity; The output form of PID is:
Here three of the increment type PID controller parameters
,
,
For obtain in step (5) those three parameters;
The expression sampling period,
Represent the setting value of corresponding step number and the error between the value of feedback,
,
,
Represent current frequency values, frequency change value and next step frequency values respectively; By increment type PID control, the actual measurement airflow value can be controlled automatically in the established standards airflow value, control accuracy is in 0.5%; Be exactly vapour lock characteristic under established standards air quantity by the vapour lock characteristic that measures this moment, and the comparison by between actual measurement vapour lock and the design vapour lock can get heat interchanger vapour lock characteristic performance index.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201310164423.2A CN103245481B (en) | 2013-05-07 | 2013-05-07 | Frequency conversion technology based detection method for air resistance characteristic of large-scale variable-load heat exchanger |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201310164423.2A CN103245481B (en) | 2013-05-07 | 2013-05-07 | Frequency conversion technology based detection method for air resistance characteristic of large-scale variable-load heat exchanger |
Publications (2)
Publication Number | Publication Date |
---|---|
CN103245481A true CN103245481A (en) | 2013-08-14 |
CN103245481B CN103245481B (en) | 2015-07-15 |
Family
ID=48925149
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201310164423.2A Active CN103245481B (en) | 2013-05-07 | 2013-05-07 | Frequency conversion technology based detection method for air resistance characteristic of large-scale variable-load heat exchanger |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN103245481B (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104569625A (en) * | 2015-01-20 | 2015-04-29 | 中国人民解放军国防科学技术大学 | Large antenna directional diagram measuring method based on rotary auxiliary antenna |
CN105929683A (en) * | 2016-06-23 | 2016-09-07 | 东南大学 | Differential adjustable PID controller parameter project adjusting method |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS59205523A (en) * | 1983-05-09 | 1984-11-21 | Omron Tateisi Electronics Co | Combustion controlling device |
US6460359B1 (en) * | 1998-05-26 | 2002-10-08 | Atlas Copco Airpower, Nv | Method and device for cool-drying |
CN101392939A (en) * | 2008-11-18 | 2009-03-25 | 天津大学 | Nonlinear prediction and control method for independence energy supply temperature of buildings |
CN102096373A (en) * | 2010-12-07 | 2011-06-15 | 昆明理工大学 | Microwave drying PID (proportion integration differentiation) control method based on increment improved BP (back propagation) neural network |
CN102645315A (en) * | 2012-04-28 | 2012-08-22 | 杭州电子科技大学 | Automatic, fast and accurate detection method for air resistance characteristics of large heat exchanger |
CN102680037A (en) * | 2012-06-06 | 2012-09-19 | 上海华东电脑系统工程有限公司 | Air quantity differential pressure calibration method applied to liquid cooling type frame |
-
2013
- 2013-05-07 CN CN201310164423.2A patent/CN103245481B/en active Active
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS59205523A (en) * | 1983-05-09 | 1984-11-21 | Omron Tateisi Electronics Co | Combustion controlling device |
US6460359B1 (en) * | 1998-05-26 | 2002-10-08 | Atlas Copco Airpower, Nv | Method and device for cool-drying |
CN101392939A (en) * | 2008-11-18 | 2009-03-25 | 天津大学 | Nonlinear prediction and control method for independence energy supply temperature of buildings |
CN102096373A (en) * | 2010-12-07 | 2011-06-15 | 昆明理工大学 | Microwave drying PID (proportion integration differentiation) control method based on increment improved BP (back propagation) neural network |
CN102645315A (en) * | 2012-04-28 | 2012-08-22 | 杭州电子科技大学 | Automatic, fast and accurate detection method for air resistance characteristics of large heat exchanger |
CN102680037A (en) * | 2012-06-06 | 2012-09-19 | 上海华东电脑系统工程有限公司 | Air quantity differential pressure calibration method applied to liquid cooling type frame |
Non-Patent Citations (2)
Title |
---|
徐丁等: "板翅式换热器翅片表面流动特性测试系统", 《杭州电子科技大学学报》, vol. 30, no. 4, 31 August 2010 (2010-08-31) * |
李相发等: "大型板翅式换热器气阻特性测控系统的开发", 《第30届中国控制会议》, 31 December 2011 (2011-12-31) * |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104569625A (en) * | 2015-01-20 | 2015-04-29 | 中国人民解放军国防科学技术大学 | Large antenna directional diagram measuring method based on rotary auxiliary antenna |
CN104569625B (en) * | 2015-01-20 | 2015-11-04 | 中国人民解放军国防科学技术大学 | A kind of large-scale antenna directional diagram measuring method based on rotatable auxiliary antenna |
CN105929683A (en) * | 2016-06-23 | 2016-09-07 | 东南大学 | Differential adjustable PID controller parameter project adjusting method |
CN105929683B (en) * | 2016-06-23 | 2019-01-18 | 东南大学 | A kind of differential is adjustable PID controller parameter engineering turning model and method |
Also Published As
Publication number | Publication date |
---|---|
CN103245481B (en) | 2015-07-15 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN104533701B (en) | A kind of automatic setting method of Turbine Governor System control parameter | |
CN109583585B (en) | Construction method of power station boiler wall temperature prediction neural network model | |
CN103912966B (en) | A kind of earth source heat pump refrigeration system optimal control method | |
CN102096373B (en) | Microwave drying PID (proportion integration differentiation) control method based on increment improved BP (back propagation) neural network | |
CN104651559B (en) | Blast furnace liquid iron quality online forecasting system and method based on multivariable online sequential extreme learning machine | |
CN102176221B (en) | Coke furnace temperature predicting method based on dynamic working conditions in coke furnace heating and burning process | |
CN111829003B (en) | Power plant combustion control system and control method | |
CN107272412A (en) | A kind of identifying approach of intermittent wind tunnel flow field control | |
CN107632524B (en) | Communication machine room temperature model prediction control method and system | |
CN112987566A (en) | Aerodynamic-thermal supercoiled nonlinear fractional order sliding-mode model-free control method | |
CN201476905U (en) | Neural network PID temperature controlled thermocouple automatic verification system | |
WO2015171196A1 (en) | Virtual flow measurement system | |
CN102998720A (en) | Method and device for calibrating dynamic response characteristic of sonde humidity by double flow method | |
Feng et al. | Predictive control model for variable air volume terminal valve opening based on backpropagation neural network | |
CN103279030B (en) | Dynamic soft measuring modeling method and device based on Bayesian frame | |
CN102419827A (en) | Radial basis function (RBF) neural network-based boiling heat exchanging prediction method | |
CN202210005U (en) | Heat energy meter flow full-automatic detection device | |
CN103245481B (en) | Frequency conversion technology based detection method for air resistance characteristic of large-scale variable-load heat exchanger | |
CN102645315B (en) | Automatic, fast and accurate detection method for air resistance characteristics of large heat exchanger | |
CN114721263A (en) | Intelligent regulation and control method for cement decomposing furnace based on machine learning and intelligent optimization algorithm | |
CN108106679B (en) | Method and system for measuring inlet air volume of coal mill of power station | |
CN104034378A (en) | Constant-current thermal gas mass flow meter and measuring method implemented by same | |
CN107730045A (en) | A kind of baseline load thermal inertia modification method based on discrete inertia force system | |
CN105090084B (en) | Draught fan online monitoring system and method | |
CN104571086B (en) | Temperature controller emulation test method based on transmission function |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C06 | Publication | ||
PB01 | Publication | ||
C10 | Entry into substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
C14 | Grant of patent or utility model | ||
GR01 | Patent grant | ||
EE01 | Entry into force of recordation of patent licensing contract |
Application publication date: 20130814 Assignee: ZHEJIANG YINBO INTELLIGENT TECHNOLOGY Co.,Ltd. Assignor: HANGZHOU DIANZI University Contract record no.: X2020330000114 Denomination of invention: Detection method of gas resistance characteristics of large heat exchanger with variable load based on frequency conversion technology Granted publication date: 20150715 License type: Common License Record date: 20201216 |
|
EE01 | Entry into force of recordation of patent licensing contract |