CN111625047A - Heating power control method for intermediate frequency power supply - Google Patents
Heating power control method for intermediate frequency power supply Download PDFInfo
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- CN111625047A CN111625047A CN202010639470.8A CN202010639470A CN111625047A CN 111625047 A CN111625047 A CN 111625047A CN 202010639470 A CN202010639470 A CN 202010639470A CN 111625047 A CN111625047 A CN 111625047A
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- G05—CONTROLLING; REGULATING
- G05F—SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES
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- G05F1/66—Regulating electric power
Abstract
The invention discloses a heating power control method of an intermediate frequency power supply, which is realized by adopting a PLC control system, a given target temperature is input in the PLC by collecting a real-time temperature signal after steel bar annealing, and a PID closed-loop regulating instruction realizes the closed-loop control of the temperature according to the current real-time temperature and the target temperature and through parameters such as proper proportion, integral time, sampling time and the like; meanwhile, a given threshold value is set for the intermediate frequency power supply, the power of a plurality of heating power supplies is given in sequence according to a power dynamic distribution algorithm, the process requirements of a production line are met, the outage rate is reduced, and the yield is improved.
Description
Technical Field
The invention particularly relates to a heating power control method of an intermediate frequency power supply, and belongs to the technical field of cold-rolled deformed steel bar production.
Background
In a cold-rolled deformed steel bar production line, a steel bar after cold rolling needs to use a medium-frequency heating power supply to perform on-line heating annealing on a deformed steel bar finished product, and generally, each production line needs to be provided with a plurality of heating power supplies. The traditional power setting of the medium-frequency heating power supply adopts a formula table look-up method, a corresponding heating formula is selected according to different speeds of a rolling mill, and the heating power which needs to be output by each power supply currently is obtained by a control system through operation table look-up according to the current speed of the rolling mill, wherein the formula table look-up method has the following defects: 1. the production line has poor operation stability, has higher requirements on process dispatching personnel, needs more skilled service and technical capabilities, and can adjust the heating power in real time according to the current equipment operation condition. 2. The adjustment is troublesome: when the strength of the raw material steel bar changes or a certain intermediate frequency power supply is damaged, the formula needs to be modified and optimized, and the production efficiency is reduced because the formula is more in quantity, time and labor are wasted in adjustment. 3. The actual temperature of the product is detected by an infrared thermometer and then is sent to an upper computer for real-time display, and an operator carries out manual fine adjustment on the formula according to the current display temperature, so that the closed-loop automatic control is not realized.
In addition, in order to further improve the product quality, the production process requires that the power of each heating power supply is given in sequence, namely, the intermediate frequency power supply closest to the outlet of the production line firstly gives the output power but cannot immediately output full power, and the intermediate frequency power supply farthest from the outlet of the production line finally gives the output power, so that the condition that a plurality of intermediate frequency power supplies simultaneously give the power when being started is avoided, and at the moment, the traditional PID heating control algorithm cannot meet the requirements of the production process.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a heating power control method of an intermediate frequency power supply, and aims to solve the problems that the heating of the existing production line can not be automatically adjusted by closed-loop control, and the power can not be dynamically distributed to a plurality of intermediate frequency heating power supplies for given output.
The technical scheme of the invention is as follows: a heating power control method of an intermediate frequency power supply is realized by adopting a PLC control system, and comprises the following specific steps:
the first step is as follows: setting n intermediate frequency power supplies for heating in the production line, wherein n is a positive integer and is more than or equal to 2, sequentially passing the steel bar through a rolling mill, the nth intermediate frequency power supply, the n-1 intermediate frequency power supply, the (DEG G and the 1 st intermediate frequency power supply, setting the set temperature Tg of the steel bar after the steel bar is taken out of the rolling mill, and measuring the actual annealing temperature Tp of the steel bar in real time after the steel bar;
the second step is that: quantizing the Tg and Tp distribution, and converting into real data Tg 'and Tp' between 0.0 and 1.0, wherein delta T = Tg '-Tp'; quantizing the power of each intermediate frequency power supply and converting the power into real numbers between 0 and 1000;
the third step: performing PID closed-loop operation in a PLC program to obtain an adjusting output quantity M, wherein M is limited to be between 0.0 and 1.0, M = Mp + Mi + Md,
wherein: gain term Mp = Kc Δ T, integral term Mi = Kc Ts/TI Δ T + Mn-1, differential term Md = Kc Td/Ts (Tp'n-1–Tp’)，
Where Kc is a proportionality coefficient, Ts is a sampling time (second), TI is an integration time (minute), and Mn-1Td is the derivative time (min), Tp'n-1Sampling a quantized value of the real-time measured temperature at the time n-1, wherein Tp' is the quantized value of the real-time measured temperature at the current time;
fourthly, calculating the total given PM = M × 1000 × n of the power of all the intermediate frequency power supplies;
fifthly, setting power reference thresholds TS1, TS2, TS (n-1) for the intermediate frequency power supplies 1, 2, and n-1 respectively, and sequentially setting power of each intermediate frequency power supply as P1, P2, and Pn after the power total given PM exceeds the reference threshold according to a power dynamic distribution algorithm, wherein PM = P1+ P2 +. cndot. + Pn.
Further, the power dynamic allocation algorithm is as follows: the total power of output is given and distributed in sequence from 1 to n-1 according to the reference threshold value set by each intermediate frequency power supply, when the reference threshold value power of the (n-1) th intermediate frequency power supply is completely reached, the power difference value (PM-TS 1-TS2- · · · · · · TS (n-1)) is evenly distributed to the n intermediate frequency power supplies, namely, a given output with the average value (PM-TS 1-TS2- · · TS (n-1))/n is evenly added to each intermediate frequency power supply on the basis of the respective reference threshold value; when the calculated given power Px of a certain power supply reaches or exceeds the full power of 1000, setting the given power Px =1000 of the power supply to be unchanged, and replacing TSx in the average value by 1000, thereby calculating the power given value of other intermediate frequency power supplies, wherein the value range of x is a positive integer between 1 and n.
Further, when n =3, Kc = 0.7-0.8, TI =230ms, Td =0, Ts = 0.1S.
The invention has the beneficial effects that: (1) by adopting PID closed-loop control, the automatic adjustment of the annealing temperature of the steel bars on the production line is realized; (2) the dynamic allocation of the given power of each intermediate frequency power supply is realized on the basis of closed-loop regulation, the defect that the power given by each power supply cannot be regulated independently due to the simultaneous regulation of a plurality of power supplies by the traditional PID algorithm is overcome, the requirement of process control on the sequential given power of a plurality of heating power supplies is met, and the control algorithm is improved and optimally designed; (3) the manual modification of the heating formula is cancelled, and the stability of the equipment is improved.
The method is put into production and use, reduces the risk of manual intervention, reduces the labor intensity, improves the yield by 0.5 percent compared with the prior art, reduces the outage rate by 2.5 percent, calculates the annual production of 400 ten thousand tons of cold-rolled twisted steel bars, and creates direct economic benefit by more than 30 ten thousand.
Drawings
Fig. 1 is a schematic view of a rebar production line.
FIG. 2 is a schematic diagram of PID closed loop temperature control in medium frequency power supply heating.
Fig. 3 is a diagram illustrating the quantization of the if power and the threshold setting.
Detailed Description
The invention will be explained and explained in more detail below with reference to the drawings.
As shown in figure 1, in the production line of the cold-rolled ribbed twisted steel, the steel bar is heated and annealed by a rolling mill and three intermediate frequency power supply heating furnaces in sequence to obtain a finished product, the numbers of the three intermediate frequency power supplies are #1, #2 and # 3 along the moving direction of the steel bar respectively, the rated power of each intermediate frequency power supply is 400-800kW, the power configurations of the three intermediate frequency power supplies can be the same or different, and the rated powers of the three selected intermediate frequency power supplies in the example are all 700 kW.
As shown in fig. 2, an infrared thermometer is installed on site after annealing, and real-time temperature signals of the annealed steel bars are collected. A given target temperature needs to be input in the PLC, and the PID closed-loop regulation instruction realizes the closed-loop control of the temperature through parameters such as proper proportion, integral time, sampling time and the like according to the current temperature and the target temperature. The production process requires that the power of each heating power supply needs to be given in sequence, namely, the power is given by 3 intermediate frequency power supplies at the same time when the 3 intermediate frequency power supplies are started according to the sequence of intermediate frequency 1- > intermediate frequency 2- > intermediate frequency 3.
The method is realized according to the following control method:
the actual annealing temperature Tp of the steel bar is measured by an infrared thermometer, the range is 400-:
Tp = AI * (1200 - 400) / 27648 + 400
wherein AI is the value of analog input module infrared temperature channel after A/D conversion, and the range is 0-27648.
The Tp and Tg need to be quantified in the program, and are converted into real data between 0.0 and 1.0:
Tp’= (Tp – 400) / (1200 – 400) = (Tp – 400)/800
Tg’= (Tg – 400) / (1200 – 400) = (Tg – 400)/800
the change amount Δ T = Tg '-Tp'.
Carrying out PID closed-loop operation in a PLC program to obtain an adjusting output quantity M, wherein M is limited between 0.0 and 1.0, and M = Mp + Mi + Md, wherein:
gain Mp = Kc Δ T
Integral term Mi = Kc Ts/TI DeltaT + Mn-1
Derivative term Md = Kc Td/Ts (Tp'n-1–Tp’)
Where Kc is a proportionality coefficient, Ts is a sampling time (second), TI is an integration time (minute), Td is a differentiation time (minute), and Mn-1Is an integral term value, Tp 'at sampling time n-1'n-1And sampling a real-time temperature quantized value at the time n-1, wherein Tp' is the real-time temperature quantized value at the current time, and determining the values according to a debugging result, wherein Kc is approximately equal to 0.7-0.8, TI is approximately equal to 230ms, Td =0, and Ts = 0.1S.
In order to realize dynamic distribution of the heating power of the intermediate frequency power supplies, as shown in fig. 3, the power of each intermediate frequency power supply is quantized between 0 and 1000, a power given reference threshold TS1 is set for intermediate frequency 1, a power given reference threshold TS2 is set for intermediate frequency 2, TS1 and TS2 are both greater than 0 and smaller than 1000, specific values of TS1 and TS2 are determined empirically, and the system output given is distributed to 3 heating power supplies according to the given reference threshold. Of course the actual power output of the intermediate frequency power supply may exceed the reference threshold. When the PLC outputs, firstly, the power is given to the intermediate frequency 1 power supply, when the given power exceeds TS1, the given power of the intermediate frequency 1 is kept unchanged, the given power of the intermediate frequency 2 is increased, and the intermediate frequency 1 is in a heat preservation state; when the power given by the intermediate frequency 2 exceeds TS2, the power difference between the total power given sum TS1 and TS2 is trisected, and then the intermediate frequency given starts to be uniformly increased by trisections at the same time for the 3 power supplies.
The power of three intermediate frequency power supplies is given PM = M × 1000 × 3 = P1+ P2+ P3, and P1, P2 and P3 represent the given output power of each power supply.
The power dynamic allocation algorithm is as follows:
(1) when PM < = TS1, P1 = PM
(2) When PM < = TS2+ TS1,
P1 = TS1
P2 = PM – TS1
(3) when PM > TS2+ TS1 and P1<1000 and P2<1000,
P1 = TS1 + (PM – TS2 – TS1) / 3
P2 = TS2 + (PM – TS2 – TS1) / 3
P3 = (PM – TS2 – TS1)/ 3
(4) when P1 or P2 outputs full power of 1000
When P1> =1000 and P2<1000,
P1 = 1000
P2 = TS2 + (PM -1000 - TS2) / 2
P3 = (PM -1000 - TS2)/2
when P2> =1000 and P1<1000,
P2 = 1000
P1 = TS1 + (PM - 1000 - TS1) / 2
P3 = (PM- 1000 - TS1) / 2
(5) when P1> =1000 and P1> =1000 and PM <3000,
P1 = P2 = 1000
P3 = PM -1000 - 1000
(6) when PM > = 3000,
P1 = P2 = P3 = 1000。
in the above method, the concept of reference thresholds TS1 and TS2 are introduced for the intermediate frequency power supply 1 and the intermediate frequency power supply 2, respectively, and the reference thresholds have the following roles: according to the process requirements, the given power of a single power supply is prevented from being too high during starting; forbidding a plurality of intermediate frequency power supplies to be given at the same time when starting; the steel bar plays a role in heat preservation and quality improvement in the heating process. In the embodiment, a PID two-section threshold value method is adopted, the given power output by closed-loop regulation is compared with a threshold value, so that the sequential given of the intermediate frequency power supplies is realized, when the given power is greater than the threshold value of one intermediate frequency power supply, the power of the power supply is kept unchanged, the heat preservation effect is realized on the heating of the steel bar, and the next intermediate frequency power supply starts to increase the output power for giving. Therefore, closed-loop regulation of temperature is guaranteed, dynamic distribution of power given by 3 medium-frequency power supplies is considered, technological requirements of production are met, stable operation of a production line is guaranteed, and the yield of ribbed steel bar products is improved.
Claims (3)
1. A heating power control method of an intermediate frequency power supply is characterized in that: the control method is realized by adopting a PLC control system, and comprises the following specific steps:
the first step is as follows: setting n intermediate frequency power supplies for heating in the production line, wherein n is a positive integer and is more than or equal to 2, sequentially passing the steel bar through a rolling mill, the nth intermediate frequency power supply, the n-1 intermediate frequency power supply, the (DEG G and the 1 st intermediate frequency power supply, setting the set temperature Tg of the steel bar after the steel bar is taken out of the rolling mill, and measuring the actual annealing temperature Tp of the steel bar in real time after the steel bar;
the second step is that: quantizing the Tg and Tp distribution, and converting into real data Tg 'and Tp' between 0.0 and 1.0, wherein delta T = Tg '-Tp'; quantizing the power of each intermediate frequency power supply and converting the power into real numbers between 0 and 1000;
the third step: performing PID closed-loop operation in a PLC program to obtain an adjusting output quantity M, wherein M is limited to be between 0.0 and 1.0, M = Mp + Mi + Md,
wherein: gain term Mp = Kc Δ T, integral term Mi = Kc Ts/TI Δ T + Mn-1, differential term Md = Kc Td/Ts (Tp'n-1–Tp’)，
Wherein KcIs a proportionality coefficient, Ts is a sampling time (second), TI is an integration time (minute), Mn-1Td is the derivative time (min), Tp'n-1Sampling a quantized value of the real-time measured temperature at the time n-1, wherein Tp' is the quantized value of the real-time measured temperature at the current time;
fourthly, calculating the total given PM = M × 1000 × n of the power of all the intermediate frequency power supplies;
fifthly, setting power reference thresholds TS1, TS2, TS (n-1) for the intermediate frequency power supplies 1, 2, and n-1 respectively, and sequentially setting power of each intermediate frequency power supply to be P1, P2, and Pn after the power total given PM exceeds the reference threshold according to a power dynamic distribution algorithm, wherein PM = P1+ P2 +. cndot. + Pn.
2. The method for controlling heating power of an intermediate frequency power supply according to claim 1, wherein: the power dynamic allocation algorithm is as follows: the total power of output is given and distributed in sequence from 1 to n-1 according to the reference threshold value set by each intermediate frequency power supply, when the reference threshold value power of the (n-1) th intermediate frequency power supply is completely reached, the power difference value (PM-TS 1-TS2- · · · · · · TS (n-1)) is evenly distributed to the n intermediate frequency power supplies, namely, a given output with the average value (PM-TS 1-TS2- · · TS (n-1))/n is evenly added to each intermediate frequency power supply on the basis of the respective reference threshold value; when the calculated given power Px of a certain power supply reaches or exceeds the full power of 1000, the given power Px =1000 of the power supply is set to be kept unchanged, and TSx in the average value is replaced by 1000, so that the power given value of other intermediate frequency power supplies is calculated.
3. The method for controlling heating power of an intermediate frequency power supply according to claim 1, wherein: when n =3, Kc takes a value of 0.7-0.8, TI =230ms, Td =0, Ts = 0.1S.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2001022197A2 (en) * | 1999-09-24 | 2001-03-29 | General Electric Company | Field upgradeable dynamic data exchange server |
| CN201444263U (en) * | 2009-07-07 | 2010-04-28 | 山东荣泰电炉制造有限公司 | Temperature closed loop control device of medium-frequency heat processing equipment |
| CN101977456A (en) * | 2010-09-06 | 2011-02-16 | 河北工业大学 | Mobile wire induction heating controller |
| CN102520630A (en) * | 2011-12-05 | 2012-06-27 | 福建星海通信科技有限公司 | Automatic power and amplitude modulation factor control circuit and power adjustment method |
| CN103678247A (en) * | 2012-08-29 | 2014-03-26 | 三星电子株式会社 | Dynamic voltage frequency scaling method and apparatus |
| CN204065899U (en) * | 2014-07-25 | 2014-12-31 | 辽宁浩方天成智能系统有限公司 | A kind of intelligent heating oil well two close cycles intermediate frequency power supply |
| CN107407954A (en) * | 2015-02-25 | 2017-11-28 | 哈尼斯菲格技术公司 | Industrial machinery with power control system |
| CN109460106A (en) * | 2018-08-21 | 2019-03-12 | 山东荣泰感应科技有限公司 | The adaptive power adjustment module and method that intermediate frequency furnace power changes with load |
-
2020
- 2020-07-06 CN CN202010639470.8A patent/CN111625047B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2001022197A2 (en) * | 1999-09-24 | 2001-03-29 | General Electric Company | Field upgradeable dynamic data exchange server |
| CN201444263U (en) * | 2009-07-07 | 2010-04-28 | 山东荣泰电炉制造有限公司 | Temperature closed loop control device of medium-frequency heat processing equipment |
| CN101977456A (en) * | 2010-09-06 | 2011-02-16 | 河北工业大学 | Mobile wire induction heating controller |
| CN102520630A (en) * | 2011-12-05 | 2012-06-27 | 福建星海通信科技有限公司 | Automatic power and amplitude modulation factor control circuit and power adjustment method |
| CN103678247A (en) * | 2012-08-29 | 2014-03-26 | 三星电子株式会社 | Dynamic voltage frequency scaling method and apparatus |
| CN204065899U (en) * | 2014-07-25 | 2014-12-31 | 辽宁浩方天成智能系统有限公司 | A kind of intelligent heating oil well two close cycles intermediate frequency power supply |
| CN107407954A (en) * | 2015-02-25 | 2017-11-28 | 哈尼斯菲格技术公司 | Industrial machinery with power control system |
| CN109460106A (en) * | 2018-08-21 | 2019-03-12 | 山东荣泰感应科技有限公司 | The adaptive power adjustment module and method that intermediate frequency furnace power changes with load |
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