CN110597322A - Heating control system and method for heat tracing band based on fuzzy PID algorithm - Google Patents
Heating control system and method for heat tracing band based on fuzzy PID algorithm Download PDFInfo
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- CN110597322A CN110597322A CN201911055294.7A CN201911055294A CN110597322A CN 110597322 A CN110597322 A CN 110597322A CN 201911055294 A CN201911055294 A CN 201911055294A CN 110597322 A CN110597322 A CN 110597322A
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D23/00—Control of temperature
- G05D23/19—Control of temperature characterised by the use of electric means
- G05D23/30—Automatic controllers with an auxiliary heating device affecting the sensing element, e.g. for anticipating change of temperature
- G05D23/32—Automatic controllers with an auxiliary heating device affecting the sensing element, e.g. for anticipating change of temperature with provision for adjustment of the effect of the auxiliary heating device, e.g. a function of time
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Abstract
A heating control system and method of a heat tracing band based on a fuzzy PID algorithm relates to the field of power grid safety control. When the temperature is controlled, the detection value of the temperature sensor is transmitted to the single chip microcomputer, the single chip microcomputer controls the heating output power according to the PID control algorithm, and when the detected temperature does not reach the preset temperature, the single chip microcomputer controls the relay to be closed to heat the heat tracing band. When the detected temperature reaches the set temperature, the relay is switched off, and heating of the heat tracing band is stopped, so that the temperature of the circuit breaker is stabilized at the target value.
Description
Technical Field
The invention belongs to the field of power grid safety control, and particularly relates to a control method for SF6And controlling the heating of the heat tracing band of the circuit breaker.
Background
The environmental temperature in winter in northern areas is lower than minus 30 ℃, SF6The gas will liquefy and will not extinguish the arc in the open condition, which will directly affect the SF6The breaking performance of the circuit breaker severely limits SF6The safe operation of the circuit breaker further influences the safe operation of the power grid. Therefore, in actual production, the tank body needs to be heated by the heat tracing band so as to ensure the air pressure in the tank. However, constant power heating is mostly adopted during heating, the heating mode is fixed, the detection precision is low, the output of the heater cannot be controlled according to the actual temperature, and a large amount of electric energy is wasted.
Disclosure of Invention
The invention aims to solve the problem of the prior pair of SF6The heating control system and the method of the heat tracing band based on the fuzzy PID algorithm are provided.
The heating belt control system based on the fuzzy PID algorithm comprises: a singlechip processing module, a signal acquisition module and an analog control output module,
the temperature value output end of the signal acquisition module is connected with the temperature value input end of the single chip microcomputer processing module, the heating power output end of the single chip microcomputer processing module is connected with the heating power input end of the analog control output module,
the signal acquisition module is used for acquiring the temperature value of the heat tracing band in real time, and the single chip microcomputer processing module comprises the following units:
a unit for judging whether the temperature value currently collected reaches a predetermined value,
when the temperature value does not reach the preset value, the temperature value is input to a unit for obtaining heating power according to the current collected temperature value,
and a unit for driving the heat tracing band to stop heating when the temperature value reaches a predetermined value.
The single chip microcomputer processing module also comprises a parameter setting unit:
obtaining the error e (t) and the error change rate ec of the current time t by using the temperature value y (t) acquired at the current time t and a preset value y (t),
e(t)＝r(t)-y(t)
wherein, e (t)1) And e (t)2) Are each t1Time t and2the error in the time of day is,
proportional coefficient K of PID controller according to fuzzy algorithm by using error e (t) and error change rate ecpIntegral coefficient KiAnd a differential coefficient KdAnd (6) setting.
The heating control method of the heat tracing band based on the fuzzy PID algorithm comprises the following steps:
the method comprises the following steps: the temperature value of the heat tracing band to be controlled is collected in real time,
step two: judging whether the temperature value currently collected reaches a preset value, if so, executing the step three, otherwise, executing the step four,
step three: controlling the heat tracing band to stop heating the breaker, returning to the step one,
step four: and inputting the currently acquired temperature value into a unit for obtaining heating power by the fuzzy PID controller, controlling the heat tracing band to heat the circuit breaker according to the heating power, and returning to the step one.
The specific method of the unit for inputting the currently acquired temperature value to the fuzzy PID controller to obtain the heating power comprises the following steps:
obtaining the error e (t) and the error change rate ec of the current time t by using the temperature value y (t) acquired at the current time t and a preset value y (t),
e(t)＝r(t)-y(t)
wherein, e (t)1) And e (t)2) Are each t1Time t and2the error in the time of day is,
proportional coefficient K of PID controller according to fuzzy algorithm by using error e (t) and error change rate ecpIntegral coefficient KiAnd a differential coefficient KdSetting;
k after settingp、Ki、KdSubstituting the PID controller into the PID controller to update the PID controller,
and (5) replacing the temperature value y (t) acquired at the current moment t with the updated PID controller to obtain the heating power.
The invention introduces a fuzzy PID (proportional integral derivative) algorithm and a singlechip processing module control system, can accurately measure the actual temperature of the heat tracing band and adjust the heating power of the heat tracing band, and saves electric energy while accurately controlling the temperature.
Drawings
FIG. 1 is a schematic structural diagram of a fuzzy PID algorithm based heating control system of a heat tracing band according to an embodiment;
FIG. 2 is a circuit diagram of a single-chip processor processing module;
FIG. 3 is a circuit diagram of a signal acquisition module;
FIG. 4 is a circuit diagram of an analog control output module;
FIG. 5 is a circuit diagram of the keyboard and the display module;
FIG. 6 is a schematic diagram of a fuzzy PID algorithm.
Detailed Description
SF6The circuit breaker arranges in each voltage class transformer substation in a large number, and northern area receives the climatic reason restriction, and the most needs cooperate the heat tracing to guarantee normal work. The following embodiments are provided for the huge amount of electricity consumed to heat the tank body every year.
The first embodiment is as follows: specifically describing the present embodiment with reference to fig. 1, the heating control system for a heat tracing band based on the fuzzy PID algorithm of the present embodiment includes: a singlechip processing module, a signal acquisition module, an analog control output module, a keyboard and display module, a data storage module and a reset module, wherein the signal acquisition module comprises a temperature sensor, a conversion circuit, an A/D converter and a photoelectric isolation circuit, the keyboard and display module comprises a keyboard and a display,
the signal output end of the keyboard is connected with the set signal input end of the single chip microcomputer processing module, the display signal input end of the display is connected with the display signal output end of the single chip microcomputer processing module, the temperature signal output end of the temperature sensor is connected with the signal input end of the conversion circuit, the voltage signal output end of the conversion circuit is connected with the analog signal input end of the A/D converter, the digital signal output end of the A/D converter is connected with the signal input end of the photoelectric isolation circuit, the signal output end of the photoelectric isolation circuit is connected with the temperature value input end of the single chip microcomputer processing module, the heating power output end of the single chip microcomputer processing module is respectively connected with the heating power input end of the analog control output module and the signal input end of the data storage module, the output end of the analog control output module is connected with the phase-shifting voltage generating circuit of the heat.
The single chip microcomputer processing module comprises the following units realized by software:
a unit for judging whether the temperature value currently collected reaches a predetermined value,
when the temperature value does not reach the preset value, the temperature value is input to a unit for obtaining heating power according to the current collected temperature value,
and a unit for driving the heat tracing band to stop heating when the temperature value reaches a predetermined value.
Specifically, the single chip microcomputer processing module further comprises a parameter setting unit:
obtaining the error e (t) and the error change rate ec of the current time t by using the temperature value y (t) acquired at the current time t and a preset value y (t),
e(t)＝r(t)-y(t)
wherein, e (t)1) And e (t)2) Are each t1Time t and2the error in the time of day is,
proportional coefficient K of PID controller according to fuzzy algorithm by using error e (t) and error change rate ecpIntegral coefficient KiAnd a differential coefficient KdAnd (6) setting.
In the present embodiment, it is preferred that,
in practical application, the signal acquisition module is responsible for acquiring the temperature of the heating belt to be controlled in real time, and a specific circuit is shown in fig. 3.
The single chip processing module is used as a control core to complete comparison processing and transmission of acquired data and regulated input data, the single chip processing module is externally connected with a crystal oscillator, and a matched chip comprises a watchdog circuit, a D trigger, a 3-8 decoder and an electrically erasable programmable read-only memory. Each chip combination completes the functions of monitoring the running state of the program of the processing module of the single chip microcomputer, improving the running reliability and parameter access. Specifically, the circuit diagram is shown in fig. 2, and includes 89C51 chips, 74HC377 chips, and 74HC138 chips. AD 00-AD 07 pins of the 89C51 chip are respectively connected with D0-D7 pins of the 74HC377 chip, and P20-P23 pins of the 89C51 chip are respectively connected with A, B, C, G1 pins of the 74HC138 chip.
The analog control output module controls the IGBT conduction phase, so that the effective value of the voltage of the primary side of the transformer is changed, and the purpose of adjusting the heating power is achieved. In the embodiment, in order to reduce the area of the circuit board and occupy the port line of the single chip microcomputer processing module, a serial digital-to-analog converter is adopted, and a non-cascade mode is selected as a working mode. The specific circuit is shown in fig. 4.
In order to realize the adjustment and control input of the system, the running state of the system and the display output of the collected data, the embodiment adopts a keyboard and a display module. The specific keyboard and display module comprises a keyboard, an LED indicator light, an 8-segment nixie tube and other display input devices. The serial mode is adopted to communicate with the microprocessor, and when regulation is not needed, the input end receives signals and displays real-time voltage and current values. When the keyboard data is read, the last clock falling edge of the reading instruction is changed into an output end, and the data is sent to the single chip microcomputer processing module. The specific circuit is shown in fig. 5.
When the detected temperature reaches the set temperature, the relay is switched off, and the heating of the heat tracing band is stopped, so that the temperature of the circuit breaker is stabilized at the target value. Because the tank body temperature control system is influenced by external environment and is a nonlinear time-varying complex system, and the parameters of the traditional PID control algorithm are fixed and not changed, the control of the tank body temperature is not ideal, the implementation mode introduces a fuzzy control theory into the PID controller, and the online self-adaptive adjustment of the PID parameters is realized by using the fuzzy control theory.
The fuzzy PID control is used for more accurately and quickly regulating the temperature, the principle of a fuzzy rule is that regulation control is considered from the aspects of stability, agility, accuracy and the like of a system, the fuzzy PID is formed by combining a fuzzy controller and a PID controller, the control rule is an important basis for fuzzy reasoning, and the fuzzy control rule is constructed. The fuzzy control rule is a fuzzy inference statement which is composed of fuzzy condition statements and takes the expression form of a judgment statement, and the principle of the fuzzy inference statement is shown in fig. 6.
In practical application, the method is suitable for being applied to circuit breakers with heat tracing bands, accurate detection and fuzzy PID algorithm control are used for improving the heating mode of the heat tracing bands, and energy and electric energy are saved by over 30%.
In the circuits shown in fig. 2-5, VOLTAGE pin, CURRENT pin of the 89C51 chip in fig. 2 and MAD _ CS # pin of the 74HC377 chip are connected to CURRENT pin, VOLTAGE pin and MAD _ CS # pin of the 3 6N137 chips in fig. 2, respectively. In fig. 3, the VI and VV pins of the two AD7895 chips are both signal acquisition terminals, and the SER _ CLK clock pin is connected to the MSER _ CLK clock pin of the 89C51 chip in fig. 2. In fig. 4, the VADJOUT pin is a signal output terminal, the MAD _ CS # pin and the DA _ CS # pin of the 6N137 chip are both connected to the MAD _ CS # pin of the 74HC377 chip in fig. 2, and the SER _ OUT pin and the SER _ CLK pin of the TLC5615 chip in fig. 4 are connected to the MSER _ OUT pin and the MSER _ CLK pin of the 89C51 chip in fig. 2, respectively. The CS1# pin, the CLK pin, the DATA pin and the KEY # pin of the HD7279A chip IN FIG. 5 are respectively connected with the MLED _ CS # pin of the 74HC377 chip IN FIG. 2, the MSER _ CLK pin, the MLED _ IN pin and the MLED _ KEY # pin of the 89C51 chip.
The second embodiment is as follows: the heating control method of the heat tracing band based on the fuzzy PID algorithm comprises the following steps:
an initialization step: setting a preset value according to the current working condition of the circuit breaker, then executing the step one,
the method comprises the following steps: the temperature value of the heat tracing band to be controlled is collected in real time,
step two: judging whether the temperature value currently collected reaches a preset value, if so, executing the step three, otherwise, executing the step four,
step three: controlling the heat tracing band to stop heating the breaker, returning to the step one,
step four: and inputting the currently acquired temperature value into a unit for obtaining heating power by the fuzzy PID controller, controlling the heat tracing band to heat the circuit breaker according to the heating power, and returning to the step one.
Specifically, the specific method of inputting the currently acquired temperature value to the unit for obtaining the heating power by the fuzzy PID controller is as follows:
obtaining the error e (t) and the error change rate ec of the current time t by using the temperature value y (t) acquired at the current time t and a preset value y (t),
e(t)＝r(t)-y(t)
wherein, e (t)1) And e (t)2) Are each t1Time t and2the error in the time of day is,
proportional coefficient K of PID controller according to fuzzy algorithm by using error e (t) and error change rate ecpIntegral coefficient KiAnd a differential coefficient KdSetting;
k after settingp、Ki、KdSubstituting the PID controller into the PID controller to update the PID controller,
and (5) replacing the temperature value y (t) acquired at the current moment t with the updated PID controller to obtain the heating power.
In practical application, the method also comprises a reset step triggered at any time according to the current working condition, and when the reset step is triggered, the initialization step is returned. And adjusting the preset value again, and controlling the heating power again for a new round.
Claims (10)
1. The heating belt control system based on the fuzzy PID algorithm is characterized by comprising the following components: a singlechip processing module, a signal acquisition module and an analog control output module,
the temperature value output end of the signal acquisition module is connected with the temperature value input end of the single chip microcomputer processing module, the heating power output end of the single chip microcomputer processing module is connected with the heating power input end of the analog control output module,
the signal acquisition module is used for acquiring the temperature value of the heat tracing band in real time, and the single chip microcomputer processing module comprises the following units:
a unit for judging whether the temperature value currently collected reaches a predetermined value,
when the temperature value does not reach the preset value, the temperature value is input to a unit for obtaining heating power according to the current collected temperature value,
and a unit for driving the heat tracing band to stop heating when the temperature value reaches a predetermined value.
2. The heating tracing band heating control system based on the fuzzy PID algorithm according to claim 1, characterized in that the single chip microcomputer processing module further comprises a parameter setting unit:
obtaining the error e (t) and the error change rate ec of the current time t by using the temperature value y (t) acquired at the current time t and a preset value y (t),
e(t)＝r(t)-y(t)
wherein, e (t)1) And e (t)2) Are each t1Time t and2the error in the time of day is,
proportional coefficient K of PID controller according to fuzzy algorithm by using error e (t) and error change rate ecpIntegral coefficient KiAnd a differential coefficient KdAnd (6) setting.
3. The fuzzy PID algorithm based heat tracing band heating control system of claim 1, further comprising a keyboard and display module,
the keyboard and display module comprises a keyboard and a display,
the signal output end of the keyboard is connected with the set signal input end of the single chip microcomputer processing module, and the display signal input end of the display is connected with the display signal output end of the single chip microcomputer processing module.
4. The fuzzy PID algorithm based heating tracing band control system of claim 1, wherein the signal collection module comprises a temperature sensor, a conversion circuit, an A/D converter and a photoelectric isolation circuit,
the temperature signal output end of the temperature sensor is connected with the signal input end of the conversion circuit, the voltage signal output end of the conversion circuit is connected with the analog signal input end of the A/D converter, the digital signal output end of the A/D converter is connected with the signal input end of the photoelectric isolation circuit, and the signal output end of the photoelectric isolation circuit is connected with the temperature value input end of the single chip microcomputer processing module.
5. The fuzzy PID algorithm based heating control system of the heat tracing band according to claim 1, wherein the output end of the analog control output module is connected with the phase shift voltage generating circuit of the heat tracing band to be controlled.
6. The fuzzy PID algorithm based heating tracing band control system of claim 1, further comprising a data storage module, wherein the heating power output terminal of the single chip processing module is connected to the signal input terminal of the data storage module.
7. The heating control method of the heat tracing band based on the fuzzy PID algorithm is characterized by comprising the following steps:
the method comprises the following steps: the temperature value of the heat tracing band to be controlled is collected in real time,
step two: judging whether the temperature value currently collected reaches a preset value, if so, executing the step three, otherwise, executing the step four,
step three: controlling the heat tracing band to stop heating the breaker, returning to the step one,
step four: and inputting the currently acquired temperature value into a unit for obtaining heating power by the fuzzy PID controller, controlling the heat tracing band to heat the circuit breaker according to the heating power, and returning to the step one.
8. The fuzzy PID algorithm based heating control method of the heat tracing band according to claim 7, wherein the specific method of inputting the current collected temperature value to the unit of the fuzzy PID controller to obtain the heating power is as follows:
obtaining the error e (t) and the error change rate ec of the current time t by using the temperature value y (t) acquired at the current time t and a preset value y (t),
e(t)＝r(t)-y(t)
wherein, e (t)1) And e (t)2) Are each t1Time t and2the error in the time of day is,
proportional coefficient K of PID controller according to fuzzy algorithm by using error e (t) and error change rate ecpIntegral coefficient KiAnd a differential coefficient KdSetting;
k after settingp、Ki、KdSubstituting the PID controller into the PID controller to update the PID controller,
and (5) replacing the temperature value y (t) acquired at the current moment t with the updated PID controller to obtain the heating power.
9. The fuzzy PID algorithm based heat tracing band heating control method according to claim 7 or 8, further comprising an initialization step before all steps are started: and setting a preset value according to the current working condition of the circuit breaker, and starting the step one.
10. The fuzzy PID algorithm based heat tracing band heating control method according to claim 9,
the method also comprises a resetting step triggered at any time according to the current working condition, and when the resetting step is triggered, the initialization step is returned.
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Cited By (3)
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| CN111708391A (en) * | 2020-06-18 | 2020-09-25 | 浙江鲜达环保科技有限公司 | Temperature control method, system and computer readable storage medium |
| CN113672005A (en) * | 2021-04-28 | 2021-11-19 | 中国科学院长春光学精密机械与物理研究所 | Intelligent heating device for photoelectric telescope and heating method thereof |
| CN114198979A (en) * | 2021-12-02 | 2022-03-18 | 纯钧新材料(深圳)有限公司 | Temperature-adjustable cold chain medicine thermal insulation box and temperature control method thereof |
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Application publication date: 20191220 |