At present, the flame detection has become a gas turbine and all kinds of the most important part of industrial boiler, steam boiler control system.
In the process of production immediately once you stop burning you must cut off the fuel supply, error often lead to flame detection signal device tripping or fire, explosion or other serious consequences.
Thus developed flame detector is very necessary.
Flame detector using sensors to detect the fire signal is converted to electrical signals first, and then the signal processing and display.
At present industrial field widely used with ultraviolet flame detector, infrared flame detector and ionic type, but they are under the bad environment can truly complete fire detection.
Flame detector is based on the flame temperature characteristic of state judgment and the fire signal is converted to a standard 4-20 ma analog signals, according to the characterization of flame combustion conditions.
In considering the environment temperature, on the basis of on the basis of fuzzy control rules determine the size of the ignition point of slope, and then measured the temperature by single chip microcomputer to calculate the rise and fall of slope, to judge the flame combustion state.
In the whole design process, first investigates the application of the market and demand situation, determine the feasibility of the development of flame detector, then the ultraviolet flame detector is given priority to with single chip microcomputer controller design.
Considering the harsh environment testing probe again easily with oil and dust and blurred, is unable to correctly detect the cause of the fire, probe the cleaning device is designed.
After the system debugging and obtain the relevant experimental data show that the maximum detection range of the flame detector can reach 45 m (
The flame of 22 mm diameter candle flame for lighting)
, and the sensitivity is very high, basically meet the requirements of the scene.
But its cleaning device since there exist problems such as untight seal.
In view of this, and after many investigation identified can work in the bad environment of intelligent temperature type flame detection system.
This scheme not only make up for the defects and self-cleaning device can be used in the occasions of various kinds of flame detection.
After the scheme is approved, draw the schematic diagram, purchased components, built on the experimental board hardware circuit and software debugging, and then make the PCB, and select the shell design the sticker, completed the software programming in C language and assembly language.
The flame detector using temperature difference value changing slope to determine the state of flame, met the rapidity;
Sensors measuring temperature, has realized the flame detection system using generalized;
Considering the influence of the external environment used the fuzzy control algorithm, it has very strong robustness.
Flame detector is particularly suitable for harsh environment test.
With strong robustness, high sensitivity, good safety, strong real-time performance, strong commonality, have higher economic value and application prospect.
Innovation in one of this paper is using fuzzy control theory to the temperature type flame detector, the second is to use the temperature rising and falling slope can meet the fast judgment of ignition and the requirements of the cut-off point.