CN112254197A - Novel temperature controller for far infrared electric floor heating system - Google Patents
Novel temperature controller for far infrared electric floor heating system Download PDFInfo
- Publication number
- CN112254197A CN112254197A CN202010945971.9A CN202010945971A CN112254197A CN 112254197 A CN112254197 A CN 112254197A CN 202010945971 A CN202010945971 A CN 202010945971A CN 112254197 A CN112254197 A CN 112254197A
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- Prior art keywords
- temperature
- temperature controller
- unit
- module
- floor heating
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D13/00—Electric heating systems
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D13/00—Electric heating systems
- F24D13/02—Electric heating systems solely using resistance heating, e.g. underfloor heating
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D19/00—Details
- F24D19/10—Arrangement or mounting of control or safety devices
- F24D19/1096—Arrangement or mounting of control or safety devices for electric heating systems
Abstract
The invention discloses a novel temperature controller for a far infrared electric floor heating system. The temperature controller module is positioned in the shell, the wiring plug is positioned at the lower side of the front surface of the shell, and the whole temperature controller can be arranged on a wall. The temperature controller module comprises a main control unit, a power supply unit, a storage unit, a timing unit, a key setting unit, a display unit, a relay module, a heating module and a temperature acquisition module. Through hardware circuit and software algorithm design, the temperature controller not only can perceive the indoor and the state of electricity ground heating in real time, realizes functions such as two accuse of two temperature, excess temperature protection and fault alarm, still has higher temperature measurement precision and energy-conserving performance. The invention is not only suitable for far infrared electric floor heating systems such as carbon fiber, carbon crystal and the like, but also suitable for electric floor heating systems such as electric heating films, heating cables, electric heating valves and the like.
Description
Technical Field
The invention relates to the technical field of electric floor heating temperature controllers, in particular to a temperature controller for a far-infrared electric floor heating system.
Background
The electric floor heating is a heating mode that a heating cable with the upper limit of 65 ℃ of working temperature is buried in a floor, the heating cable is used as a heat source to heat the floor or a ceramic tile, and a temperature controller is used to control the room temperature or the ground temperature to realize ground radiation heating. The electric floor heating is the heating cable at first, then is the electric heat membrane, and the carbon crystal, carbon fiber material are popular recently. Compared with heating cables such as alloy and metal, the carbon fiber floor heating sheet, the heating cable and the heating sheet directly convert electric energy into heat energy by almost 100 percent, and transmit the heat energy to the indoor space through the ground in a far infrared radiation mode, so that the energy is saved, the environment is protected, and the radiation is relatively conducted and the convection transmission is more comfortable. Therefore, far infrared electric floor heating becomes one of the ideal, advanced, energy-saving and healthy heating modes recognized at present.
With the continuous increase of the number of far infrared electric floor heating devices, the safety of the far infrared electric floor heating devices is more and more concerned by people. The temperature controller is an important component and a control core of the far infrared electric floor heating system. If adopt and warm up itself with the electricity and mismatch, perhaps the not good temperature controller of performance causes potential safety hazards such as conflagration very easily. Therefore, the temperature controller for the carbon fiber electric floor heating with reliable design performance is the problem which needs to be solved urgently at present.
Along with the continuous increase of far infrared electric floor heating use quantity, its comfort level also receives people's attention more and more. The temperature controller is the core for realizing temperature control, and the comfort level is greatly reduced when the temperature is too high or too low. Too high temperature can also reduce the carbon fiber service life and increase the heating expense. At present, the temperature controllers of far infrared electric floor heating systems in the market are not satisfactory in the aspects of control precision and stability.
Disclosure of Invention
The invention aims to design a novel temperature controller for a far infrared electric floor heating system through hardware circuit and software algorithm design, and the novel temperature controller has the functions of double-temperature double control, over-temperature protection, fault alarm and the like, and also has higher control precision and energy-saving performance.
The technical scheme of the invention is as follows:
a novel temperature controller for a far infrared electric floor heating system comprises a temperature controller, a temperature acquisition module, a relay module and a heater module, wherein the temperature controller is electrically connected with the temperature acquisition module and is also electrically connected with the heater module through the relay module;
the heater module is used for heating;
the temperature acquisition module comprises a first temperature sensor and a second temperature sensor, wherein the first temperature sensor is arranged on the temperature controller and is used for acquiring room temperature and transmitting the room temperature to the temperature controller; the second temperature sensor is arranged on the heater module and used for collecting the temperature of the electric floor heating and transmitting the temperature to the temperature controller;
the relay module is used for switching on or off the heater module;
the temperature controller comprises a main control unit, a power supply unit, a storage unit, a timing unit, a key setting unit and a display unit; the main control unit is electrically connected with the power supply unit, the storage unit, the timing unit, the key setting unit, the display unit, the first temperature sensor, the second temperature sensor and the relay module respectively;
the power supply unit is used for supplying electric energy;
the key setting unit is used for setting temperature;
the main control unit is used for sending and receiving clock signals to the timing unit, circularly detecting key signals sent by the key setting unit, displaying time and temperature in real time through the display unit, storing data collected by the temperature collection module into the storage unit and controlling the relay module to work according to the data collected by the temperature collection module and the temperature set by the key setting unit.
As a further optimization scheme of the novel temperature controller for the far-infrared electric floor heating system, the heating module adopts any one of carbon fiber, carbon crystal, an electrothermal film, a heating cable and an electrothermal valve.
As a further optimization scheme of the novel temperature controller for the far-infrared electric floor heating system, an AVR microprocessor with the model number of ATmega16 is selected as the main control unit.
As a further optimization scheme of the novel temperature controller for the far infrared electric floor heating system, a DS1302 clock chip is adopted by the timing unit.
As a further optimization scheme of the novel temperature controller for the far infrared electric floor heating system, the display unit adopts an LCD.
As a further optimization scheme of the novel temperature controller for the far-infrared electric floor heating system, the first temperature sensor and the second temperature sensor both adopt NTC thermistors and are connected with an I/O port of an AVR microprocessor.
As a further optimization scheme of the novel temperature controller for the far-infrared electric floor heating system, the temperature acquired by the first temperature sensor and the temperature acquired by the second temperature sensor are filtered by combining a median filtering method and a pulse interference prevention value filtering method, the deviation between the acquired temperature and the real temperature is compensated by adopting a linear compensation method, and the work of a relay module is controlled by adopting a PID algorithm.
The key setting unit comprises a power key, a function key, a clock key, an increase key and a decrease key, wherein the function key adopts a single key and a combination key and is respectively connected with the AVR microprocessor and the ground. The temperature controller is set and operated by long-press, short-press, combination keys and other function keys, including setting modes, temperature, time and the like. The setting mode comprises a real-time operation mode and a one-week programmable mode, and the one-week programmable mode can enable a user to maintain the room temperature at different setting temperatures in 6 time periods in one day. The key setting unit is used for designing a key jitter elimination detection circuit based on an RC filter circuit so as to eliminate key jitter.
Compared with the prior art, the invention adopting the technical scheme has the following technical effects:
the invention realizes the functions of double temperature control and over temperature protection and meets the requirements of people on the use safety and comfort of the temperature controller.
The setting mode is divided into an automatic real-time operation mode and an intelligent one-week programmable mode, so that different requirements of a user on temperature at different time are met, energy is saved, the system is humanized, and the use comfort level is improved.
In the invention, because a filtering method, a linear compensation method and a PID control algorithm which combine a median filtering method and a pulse interference prevention value filtering method are adopted during temperature acquisition, processing and control software design, the temperature control precision is improved. Meanwhile, the key jitter elimination detection circuit is adopted, and key jitter is eliminated, so that the control device has better control precision and stability, and meets the requirements of people on the quality of the temperature controller.
Drawings
FIG. 1 is a system schematic block diagram of a thermostat module of the present invention;
FIG. 2 is a schematic diagram of the hardware components of the thermostat module of the present invention;
FIG. 3 is a flowchart of a main process of the thermostat module according to the present invention;
fig. 4 is a working schematic diagram of the linear compensation method of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
As shown in fig. 1 and 2, the invention discloses a novel temperature controller for a far-infrared electric floor heating system, which comprises a temperature controller, a temperature acquisition module, a relay module and a heater module, wherein the temperature controller is electrically connected with the temperature acquisition module and is also electrically connected with the heater module through the relay module;
the heater module is used for heating;
the temperature acquisition module comprises a first temperature sensor and a second temperature sensor, wherein the first temperature sensor is arranged on the temperature controller and is used for acquiring room temperature and transmitting the room temperature to the temperature controller; the second temperature sensor is arranged on the heater module and used for collecting the temperature of the electric floor heating and transmitting the temperature to the temperature controller;
the relay module is used for switching on or off the heater module;
the temperature controller comprises a main control unit, a power supply unit, a storage unit, a timing unit, a key setting unit and a display unit; the main control unit is electrically connected with the power supply unit, the storage unit, the timing unit, the key setting unit, the display unit, the first temperature sensor, the second temperature sensor and the relay module respectively;
the power supply unit is used for supplying electric energy;
the key setting unit is used for setting temperature;
the main control unit is used for sending and receiving clock signals to the timing unit, circularly detecting key signals sent by the key setting unit, displaying time and temperature in real time through the display unit, storing data collected by the temperature collection module into the storage unit and controlling the relay module to work according to the data collected by the temperature collection module and the temperature set by the key setting unit.
The heating module adopts any one of carbon fiber, carbon crystal, an electrothermal film, a heating cable and an electrothermal valve.
The output end of the power supply unit is electrically connected with the input end of the main control unit, the storage unit is connected with the I/O interface of the main control unit through an IIC bus interface, the timing unit is connected with the I/O interface of the main control unit through three interface data lines of I/O, CE and SCLK, each key in the key setting unit is connected with the I/O interface of the main control unit respectively, and the display unit is connected with the SPI serial interface of the main control unit through the SPI serial interface. The input end of the relay module is electrically connected with the output end of the main control unit, the output end of the relay module is electrically connected with the input end of the heater control module, and the temperature acquisition module is connected with the I/O port of the main control unit.
The main control unit is an AVR microprocessor with the model of ATmega 16. ATmega16 contains programmable Flash, 32 general purpose I/O ports, programmable watchdog timer and an SPI serial port. ATmega16 is connected with the storage unit, the timing unit, the temperature acquisition module, the key setting unit, the display unit and the relay module through the I/O interface and the SPI serial port. The storage unit adopts an AT24C02 memory chip, has the storage capacity of 2 kbit and is connected with an I/O interface of ATmega16 through an IIC bus interface. ATmega16 stores the data in the storage unit, and reads the data in the storage unit arbitrarily, thereby effectively solving the problem of power failure data loss.
The power supply unit provides 12V and 3.3V voltage for the relay, ATmega16 microprocessor chip, AT24C02 memory chip, DS1302 clock, etc.
The timing unit adopts a DS1302 clock chip. The DS1302 clock chip adopts a three-wire interface to synchronously communicate with the AVR microprocessor, can time the year, month, day, week, hour, minute and second and has a leap year compensation function. The 3v lithium battery is adopted as the standby power supply so that data is not lost after the power failure of the main power supply, and the standby power supply is charged through programming, so that the clock can still continuously and accurately run under the condition that the main power supply is turned off.
The key setting unit comprises a power key, a function key, a clock key, an increase key and a decrease key, wherein the function key adopts a single key and a combination key and is respectively connected with the AVR microprocessor and the ground. The temperature controller is set and operated by long-press, short-press, combination keys and other function keys, including setting modes, temperature, time and the like. The setting mode comprises a real-time operation mode and a one-week programmable mode, and the one-week programmable mode can enable a user to maintain the room temperature at different setting temperatures in 6 time periods in one day. The key setting unit is used for designing a key jitter elimination detection circuit based on an RC filter circuit so as to eliminate key jitter.
The display unit adopts an LCD. LCD liquid crystal display adopts SPI serial interface to link to each other with AVR microprocessor's SPI serial interface, can show and set for parameters such as mode, clock, indoor temperature and time, carbon fiber electricity warm up operating temperature and heating state, and the system sends the warning when the temperature in the room exceedes the standard value.
The first temperature sensor and the second temperature sensor both adopt NTC thermistors and are connected with an I/O port of an AVR microprocessor.
The invention adopts a median filtering method and a pulse interference prevention value filtering method to combine to filter the temperature collected by the first and second temperature sensors, adopts a linear compensation method to compensate the deviation between the collected temperature and the real temperature, and adopts a PID algorithm to control the temperature.
As shown in FIG. 2, the main control unit is an AVR single chip microcomputer, and the main processor is ATmega16 in AVR series. The model number of the memory cell is AT24C 02. The model of the temperature sensor is an NTC thermistor with B value of 3950 and 10 k. The model of the timing unit is a DS1302 clock chip, and a 3v lithium battery is added to be used as a standby power supply. The display unit is an LCD liquid crystal screen and is connected with an SPI serial port of ATmega 16. The heater module is a carbon fiber thermal cable.
As shown in fig. 3, the main control unit and the temperature acquisition module together implement temperature acquisition, processing and control functions. The main process comprises the following steps: two NTC thermistors are respectively arranged under the temperature controller and the carbon fiber floor heating, and the NTC thermistors and a resistor are connected in series to form a series voltage division circuit, so that the NTC resistance value corresponding to the temperature value is obtained. And then, the microprocessor obtains a temperature value through A/D conversion, and performs filtering by adopting a method combining a median filtering method and an anti-pulse interference value filtering method. Then, for the nonlinearity of the temperature-resistance characteristic of the NTC thermistor, the temperature measurement result is compensated by using a linear compensation method as shown in fig. 4, and finally, the main control unit compares the real-time temperature with the set temperature, and outputs a control quantity to control the relay module through a PID control algorithm when the real-time temperature is greater than or less than the set temperature.
The difference between the temperature controller working in the programming mode and the common mode is that the set value of the temperature is not fixed and changes along with the change of time, and the software design firstly calculates the current time in one of six time periods, and then calculates the temperature of the current time period by combining the current date.
It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
The above-mentioned embodiments, objects, technical solutions and advantages of the present invention are further described in detail, it should be understood that the above-mentioned embodiments are only illustrative of the present invention and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (7)
1. The novel temperature controller for the far-infrared electric floor heating system is characterized by comprising a temperature controller, a temperature acquisition module, a relay module and a heater module, wherein the temperature controller is electrically connected with the temperature acquisition module and is also electrically connected with the heater module through the relay module;
the heater module is used for heating;
the temperature acquisition module comprises a first temperature sensor and a second temperature sensor, wherein the first temperature sensor is arranged on the temperature controller and is used for acquiring room temperature and transmitting the room temperature to the temperature controller; the second temperature sensor is arranged on the heater module and used for collecting the temperature of the electric floor heating and transmitting the temperature to the temperature controller;
the relay module is used for switching on or off the heater module;
the temperature controller comprises a main control unit, a power supply unit, a storage unit, a timing unit, a key setting unit and a display unit; the main control unit is electrically connected with the power supply unit, the storage unit, the timing unit, the key setting unit, the display unit, the first temperature sensor, the second temperature sensor and the relay module respectively;
the power supply unit is used for supplying electric energy;
the key setting unit is used for setting temperature;
the main control unit is used for sending and receiving clock signals to the timing unit, circularly detecting key signals sent by the key setting unit, displaying time and temperature in real time through the display unit, storing data collected by the temperature collection module into the storage unit and controlling the relay module to work according to the data collected by the temperature collection module and the temperature set by the key setting unit.
2. The novel temperature controller for the far-infrared electric floor heating system as claimed in claim 1, wherein the heating module is any one of carbon fiber, carbon crystal, electric heating film, heating cable and electric heating valve.
3. The novel temperature controller for the far-infrared electric floor heating system as claimed in claim 1, wherein the main control unit is an AVR microprocessor with model number ATmega 16.
4. The novel temperature controller for far-infrared electric floor heating system of claim 1, characterized in that the timing unit adopts a DS1302 clock chip.
5. The novel temperature controller for the far-infrared electric floor heating system as claimed in claim 1, wherein the display unit is an LCD liquid crystal display.
6. The novel temperature controller for a far-infrared electric floor heating system as claimed in claim 1, wherein the first and second temperature sensors are both NTC thermistors.
7. The novel temperature controller for the far-infrared electric floor heating system according to claim 1, wherein the temperature collected by the first and second temperature sensors is filtered by combining a median filtering method and a pulse interference prevention value filtering method, the deviation between the collected temperature and the real temperature is compensated by a linear compensation method, and a PID algorithm is adopted to control the relay module to work.
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| CN202010945971.9A CN112254197A (en) | 2020-09-10 | 2020-09-10 | Novel temperature controller for far infrared electric floor heating system |
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| CN202010945971.9A CN112254197A (en) | 2020-09-10 | 2020-09-10 | Novel temperature controller for far infrared electric floor heating system |
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