Coal mill coal seam thickness monitoring device and method based on RFID sign-in
By installing RFID tags on the coal seam gauge of the coal mill, and combining radio frequency signals and algorithms, accurate monitoring and automatic adjustment of the coal seam thickness of the coal mill have been achieved. This solves the problem of inaccurate coal seam thickness monitoring in existing technologies and reduces the risk of equipment failure and maintenance costs.
Patent Information
- Application Number
- CN202510894270.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-30
- Publication Date
- 2025-11-28
AI Technical Summary
Existing coal mills cannot accurately monitor coal seam thickness, leading to inaccurate load adjustment, which can easily cause equipment failure and damage. Furthermore, traditional monitoring methods are unstable in harsh environments.
A coal seam thickness monitoring device based on RFID check-in is adopted for coal mills. By installing passive RFID tags on the coal seam gauge, and using radio frequency signals and electromagnetic signal feedback, combined with Kalman filtering and PID closed-loop control algorithms, the accurate quantification and automatic adjustment of coal seam thickness can be achieved.
It enables precise monitoring of coal seam thickness, reduces the risk of equipment failure, lowers maintenance costs, adapts to the harsh environment of coal mills, and extends equipment life.
Smart Images
Figure CN121026027A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of coal mill operation monitoring, in particular to a coal mill coal layer thickness monitoring device and method based on RFID signing. BACKGROUND
[0002] As the core equipment of the power plant pulverizing system, the coal mill gradually develops its operation state monitoring technology with the industrial demand. In actual operation, the coal mill in the power plant generally has faults such as the fracture of the hinge shaft of the hydraulic cylinder of the grinding roller and the serious wear of the wear-resistant parts. The reason is that the grinding roller of the coal mill has no visual monitoring at present, only has the in-place signal, and the coal layer thickness cannot be well monitored. Since the coal type is frequently replaced, the grindability coefficients of different coal types differ greatly, there is no quantitative standard, the load of the grinding roller is often too large or too small, which affects the safety of the equipment and the operation safety. In addition, there are occasionally hard objects in the coal entering the furnace, which will also damage the equipment after entering the coal mill.
[0003] In the early stage, the operation of the coal mill mainly relies on manual inspection and experience judgment, and the coal layer thickness is inferred by observing the indirect indexes such as equipment vibration, sound and outlet coal fineness. There is a lack of direct monitoring means, and the error is large and the response is lagging. With the development of automatic technology, simple limit switches or in-place signal sensors are gradually introduced, which can only judge whether the grinding roller is in the "in-place" state, and cannot quantify the coal layer thickness and the displacement of the grinding roller, and still cannot meet the precise adjustment demand.
[0004] In recent years, in order to realize more precise monitoring, some scenes try to use infrared displacement measurement technology to indirectly reflect the coal layer thickness by feeding back the position change of the grinding roller through optical signals, but the application of this technology in the special environment of the coal mill is limited.
[0005] At present, a durable detection device that can directly monitor the coal layer thickness, output continuous and accurate displacement data, provide quantitative basis for load adjustment, and is not restricted for daily monitoring by the operator is needed. SUMMARY
[0006] The purpose of the present application is to overcome the defects of the prior art and provide a coal mill coal layer thickness monitoring device and method based on RFID signing.
[0007] The purpose of the present application can be realized by the following technical solutions:
[0008] A coal mill coal layer thickness monitoring device based on RFID signing, comprising a coal mill, the device comprising: a passive RFID tag and an RFID signing machine, the RFID tag is installed at a preset position of the coal layer of the coal mill and a wear indicator scale, and the RFID signing machine is installed on the outer bracket of the lower pull rod of the grinding roller of the coal mill.
[0009] The RFID sign-in machine comprises a radio frequency signal emitting module and an electromagnetic signal receiving module, when the RFID sign-in machine moves with the pull rod under the grinding roller, it intersects with the RFID tags in different positions in turn, the radio frequency signal emitting module emits radio frequency signals outward at a preset frequency, the electromagnetic signal receiving module receives the returned electromagnetic signals, the RFID tag comprises an electromagnetic chip which changes the electromagnetic characteristics when receiving the moving radio frequency signals and then emits electromagnetic signals.
[0010] Further, the RFID tag further comprises a tag shell and an internal antenna, the internal antenna is connected with the electromagnetic chip, and the internal antenna and the electromagnetic chip are both arranged in the tag shell.
[0011] Further, the tag shell is detachably connected with the coal layer of the coal mill and the wear indicator scale through a sliding rail or is detachably connected through a nut, and the tag shell comprises a sliding rail and a threaded through hole.
[0012] Further, the electromagnetic characteristics of different RFID tags are different, and the electromagnetic signals emitted by the RFID tags when the electromagnetic characteristics change after receiving the moving radio frequency signals are also different.
[0013] Further, the preset positions of the coal layer of the coal mill and the wear indicator scale include 0mm, ±20mm, ±40mm and ±60mm, the RFID tags are installed in a linear arrangement along the vertical direction of the coal layer in the coal mill, and the installation spacing between adjacent RFID tags is a fixed spacing.
[0014] Further, when the RFID sign-in machine intersects with the RFID tags in different positions, the distance between the RFID sign-in machine and the RFID tags is 0.1-1m.
[0015] Further, the RFID sign-in machine further comprises an internal shock absorbing support.
[0016] A monitoring method of a coal layer thickness monitoring device of a coal mill based on RFID sign-in as described above, the method comprises:
[0017] Using the RFID sign-in machine, emitting radio frequency signals outward at a preset frequency, and receiving the electromagnetic signals fed back by the RFID tags in different positions under the radio frequency signals;
[0018] Counting the receiving times and frequencies of the electromagnetic signals fed back by the RFID tags in different positions within a unit time, and calculating the proportion P of the receiving times of the electromagnetic signals fed back by the RFID tags in the ±20mm position within a unit time in the total receiving times;
[0019] When P is less than the first proportion threshold value and the receiving frequency of the electromagnetic signal fed back by the label at 40mm or 60mm is higher than the frequency threshold value, the coal mill loading force is increased; when P is greater than the second proportion threshold value and the receiving frequency of the electromagnetic signal fed back by the label at-20mm is higher than the frequency threshold value, the coal mill loading force is reduced;
[0020] If the electromagnetic signal fed back by the label is not received within the preset time, a hydraulic cylinder hinge shaft fracture early warning is generated; if the change rate of the receiving frequency of the electromagnetic signal fed back by the label exceeds the change threshold value without changing the coal type, a coal mill internal foreign matter early warning is generated.
[0021] Further, when receiving the electromagnetic signal fed back by the RFID label at each position under the radio frequency signal, the Kalman filtering algorithm is used to process the electromagnetic signal.
[0022] Further, when the coal mill loading force is increased or reduced, the PID closed-loop control algorithm is used for control.
[0023] Compared with the prior art, the beneficial effects of the present application include:
[0024] 1. The present application installs RFID labels at preset positions such as 0mm, ±20mm, ±40mm and ±60mm of the coal seam ruler, combines the real-time receiving and statistics of the label signal by the sign-in machine, can directly reflect the displacement of the grinding roller, and further accurately quantifies the thickness of the coal seam, solves the problem that the traditional method only relies on the "in-place signal" and cannot be quantitatively monitored, and provides a clear basis for loading force adjustment; and different RFID labels in the present application have unique electromagnetic characteristics, and the feedback signals are different, so that different position labels can be accurately distinguished, and signal confusion can be avoided.
[0025] 2. The present application can automatically judge the abnormality of the coal seam thickness by monitoring the receiving frequency of the label signal at different positions, avoid metal collision or blockage caused by excessive loading force, reduce the wear of the grinding roller wear-resistant parts and the fracture of the hydraulic cylinder hinge shaft, and avoid the risk of equipment damage in advance by early warning of signal abnormalities such as hinge shaft fracture and internal foreign matter.
[0026] 3. The present application uses passive RFID labels without power supply, cooperates with the radio frequency signal transmission of the sign-in machine, can withstand harsh environments such as high temperature, oil stains, moisture and dust inside the coal mill, solves the problem of unstable signal of traditional optical measurement (such as infrared rays) which is easy to be blocked, and ensures long-term reliable operation.
[0027] 4. The passive RFID label in the present application is integrated with a shell, an internal antenna and an electromagnetic chip, the shell is detachably connected through a sliding rail or a nut, and the installation, replacement and position adjustment are facilitated, thereby reducing the maintenance cost.
[0028] 5. The application is based on RFID technology non-contact measurement, through physical displacement caused by electromagnetic characteristics of the label change to achieve monitoring, without direct contact with the coal seam or grinding roller, reducing equipment wear, prolong the service life. BRIEF DESCRIPTION OF DRAWINGS
[0029] Figure 1 For the device structure example of the application;
[0030] Figure 2 For the RFID tag structure example of the application;
[0031] Figure 3 For the method flow chart of the application;
[0032] In the figure, 1-RFID tag, 2-RFID check-in machine, 11-label shell, 12-built-in antenna, 13-electromagnetic chip. DETAILED DESCRIPTION
[0033] The technical solutions in the embodiments of the application will be apparently and completely described below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without creative labor should belong to the protection scope of the application.
[0034] Embodiment 1
[0035] This embodiment discloses a kind of coal mill coal seam thickness monitoring device based on RFID check-in, this device is installed on coal mill, specifically as shown in Figure 1 The device includes: passive RFID tag 1 and RFID check-in machine 2. RFID tag 1 is installed in the preset position of coal seam and wear indicator scale of coal mill, and RFID check-in machine 2 is installed on the outer bracket of the lower pull rod of the grinding roller of coal mill.
[0036] Passive RFID tag without power supply can withstand high temperature, oil stain, damp, dust and other harsh environments inside coal mill.
[0037] The preset position of coal seam and wear indicator scale of coal mill includes 0mm, ±20mm, ±40mm and ±60mm, and RFID tag 1 is installed in linear arrangement along the vertical direction of coal seam in coal mill. The installation interval between adjacent RFID tags 1 is fixed interval.
[0038] RFID tag 1 is as shown in Figure 2As shown, it is a long strip-shaped label, including a label shell 11, an internal antenna 12 and an electromagnetic chip 13 which changes electromagnetic characteristics when receiving a mobile radio frequency signal and then emits an electromagnetic signal. The electromagnetic characteristics of the electromagnetic chip 13 in different RFID tags 1 are different, and the electromagnetic signals emitted by the electromagnetic characteristics when receiving a mobile radio frequency signal are also different. The feedback signals are different, and different position labels can be accurately distinguished to avoid signal confusion.
[0039] The internal antenna 12 is connected with the electromagnetic chip 13, and the internal antenna 12 and the electromagnetic chip 13 are both placed in the label shell 11.
[0040] The label shell 11 is detachably connected with the coal layer of the coal mill and the wear indicator scale through a sliding rail or through a nut, and the label shell 11 includes a sliding rail and a threaded through hole, which facilitates installation, replacement and position adjustment, and reduces maintenance cost.
[0041] The RFID sign-in machine 2 includes a radio frequency signal emitting module and an electromagnetic signal receiving module. When the RFID sign-in machine 2 moves with the lower pull rod of the grinding roller, it sequentially intersects with the RFID tags 1 at different positions in parallel, the radio frequency signal emitting module emits radio frequency signals outward at a preset frequency, and the electromagnetic signal receiving module receives the returned electromagnetic signals.
[0042] By installing RFID tags at preset positions such as 0mm, ±20mm, ±40mm, ±60mm of the coal layer scale, combined with the real-time receiving and statistics of the label signal by the sign-in machine, the displacement of the grinding roller can be directly reflected, and the coal layer thickness can be accurately quantified.
[0043] When the RFID sign-in machine 2 intersects with the RFID tags 1 at different positions in parallel, the distance between the RFID sign-in machine 2 and the RFID tags 1 is 0.1-1m. The RFID sign-in machine 2 also has a built-in shock-absorbing bracket to reduce vibration interference when collecting electromagnetic signals.
[0044] The installation angle of the RFID sign-in machine 2 is 10°-15° to enhance the signal penetration.
[0045] Compared with the traditional infrared displacement measurement, the use of RFID tags does not require power, has low equipment cost and low maintenance cost, is resistant to harsh environments such as high temperature, oil stain and moisture, has long service life, and passively scans to trigger electromagnetic signals, which have strong electromagnetic signal penetration and are not easily blocked, making it easier to collect.
[0046] Embodiment 2
[0047] The embodiment discloses a monitoring method of a coal mill coal layer thickness monitoring device based on RFID sign-in as disclosed in Embodiment 1 above, and the method includes Figure 3 as shown:
[0048] Step S1, using the RFID sign-in machine, externally emit radio frequency signals at a preset frequency, and receive the electromagnetic signals fed back by the RFID tags at each position under the radio frequency signals;
[0049] Step S2, count the receiving times and frequencies of the electromagnetic signals fed back by the tags at each position within a unit time;
[0050] Step S3, calculate the proportion P of the receiving times of the electromagnetic signals fed back by the tags at positions of ±20mm in the total receiving times within a unit time;
[0051] Step S4, generate a loading force adjustment instruction or a warning according to the receiving times, frequencies and proportions of the electromagnetic signals.
[0052] In step S1, when receiving the electromagnetic signals fed back by the RFID tags at each position under the radio frequency signals, the Kalman filtering algorithm is used to process the electromagnetic signals.
[0053] In step S4, when P is less than a first proportion threshold and the receiving frequencies of the electromagnetic signals fed back by the tags at positions of 40mm or 60mm are higher than a frequency threshold, the loading force of the coal mill is increased; when P is greater than a second proportion threshold and the receiving frequency of the electromagnetic signals fed back by the tags at a position of -20mm is higher than the frequency threshold, the loading force of the coal mill is decreased;
[0054] If the electromagnetic signals fed back by the tags are not received within a preset time, a hydraulic cylinder hinge shaft fracture warning is generated; if the change rate of the receiving frequencies of the electromagnetic signals fed back by the tags exceeds a change threshold without changing the coal type, a foreign matter inside the coal mill warning is generated.
[0055] When the loading force of the coal mill is increased or decreased, the PID closed-loop control algorithm is used for control.
[0056] Through the calculation method of the embodiment 2, the thickness of the coal layer in the coal mill can be stabilized at about 20mm.
[0057] The working process of the above device and method is as follows:
[0058] When the grinding roller of the coal mill moves, the RFID sign-in machine is started to read the tag signals in real time, and the 20mm tag signal triggering frequency is the highest in the normal state;
[0059] The system calculates the loading force adjustment amount through the PID algorithm, increases the loading force when the 40mm tag triggering proportion is greater than 30%, and decreases the loading force when the 0mm tag triggering proportion is greater than 20%;
[0060] If there is no signal for 30s continuously or the frequency fluctuation exceeds 50%, a first-level warning is generated to prompt on-site inspection.
[0061] The above merely illustrates the specific embodiments of the present application, but the protection scope of the present application is not limited thereto, and any skilled person in the art can easily think of various equivalent modifications or replacements within the technical range disclosed by the present application, and these modifications or replacements shall be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.
Claims
1. A coal bed thickness monitoring device for a coal pulverizer based on RFID tagging, comprising a coal pulverizer, characterized by, The device includes: a passive RFID tag (1) and an RFID check-in machine (2). The RFID tag (1) is installed at a preset position on the coal layer and wear indicator scale of the coal mill, and the RFID check-in machine (2) is installed on the external support of the grinding roller pull rod of the coal mill. The RFID check-in machine (2) includes a radio frequency signal transmitting module and an electromagnetic signal receiving module. When the RFID check-in machine (2) moves with the grinding roller pull rod, it intersects with the RFID tags (1) at different positions in sequence. The radio frequency signal transmitting module transmits radio frequency signals to the outside at a preset frequency. The electromagnetic signal receiving module receives the returned electromagnetic signals. The RFID tag (1) includes an electromagnetic chip (13) whose electromagnetic characteristics change when it receives the moving radio frequency signal and then emits an electromagnetic signal.
2. The coal seam thickness monitoring device for a coal mill based on RFID check-in as described in claim 1, characterized in that, The RFID tag (1) also includes a tag shell (11) and a built-in antenna (12). The built-in antenna (12) is connected to an electromagnetic chip (13), and both the built-in antenna (12) and the electromagnetic chip (13) are placed inside the tag shell (11).
3. The RFID-based coal seam thickness monitoring device for a coal mill according to claim 2, characterized in that, The label housing (11) is detachably connected to the coal seam and wear indicator scale of the coal mill via a slide rail or via a nut. The label housing (11) includes a slide rail and a threaded through hole.
4. The coal seam thickness monitoring device for a coal mill based on RFID check-in as described in claim 1, characterized in that, Different RFID tags (1) have different electromagnetic characteristics, and the electromagnetic signals emitted by the changes in their electromagnetic characteristics when they receive mobile radio frequency signals are also different.
5. The coal seam thickness monitoring device for a coal mill based on RFID check-in according to claim 1, characterized in that, The preset positions of the coal seam and wear indicator scale of the coal mill include 0mm, ±20mm, ±40mm and ±60mm. The RFID tags (1) are linearly arranged and installed along the vertical direction of the coal seam in the coal mill, and the installation spacing between adjacent RFID tags (1) is a fixed spacing.
6. The coal seam thickness monitoring device for a coal mill based on RFID check-in according to claim 1, characterized in that, When the RFID check-in machine (2) intersects with the RFID tag (1) at different locations in parallel, the distance between the RFID tag (1) and the RFID tag (1) is 0.1-1m.
7. A coal seam thickness monitoring device for a coal mill based on RFID check-in according to claim 1, characterized in that, The RFID check-in machine (2) also has a built-in shock-absorbing bracket.
8. A monitoring method based on the RFID-based check-in coal seam thickness monitoring device for a coal mill as described in any one of claims 1-7, characterized in that, The method includes: Using an RFID check-in machine, radio frequency signals are emitted outward at a preset frequency, and electromagnetic signals fed back by RFID tags at each location under the radio frequency signals are received. The number of times and frequency of electromagnetic signals received by tags at each location within a unit time are statistically analyzed, and the percentage P of the number of times electromagnetic signals received by tags at the ±20mm location within a unit time is calculated in the total number of times received. When P is less than the first percentage threshold and the receiving frequency of the electromagnetic signal fed back by the tag at 40mm or 60mm is higher than the frequency threshold, the loading force of the coal mill is increased; when P is greater than the second percentage threshold and the receiving frequency of the electromagnetic signal fed back by the tag at -20mm is higher than the frequency threshold, the loading force of the coal mill is decreased. If no electromagnetic signal is received from the tag within a preset time, a hydraulic cylinder hinge shaft breakage warning is generated; if the rate of change of the receiving frequency of the electromagnetic signal from the tag exceeds the change threshold, and the coal type remains unchanged, a foreign object warning is generated inside the coal mill.
9. A method for monitoring coal seam thickness in a coal mill based on RFID check-in, as described in claim 8, characterized in that, When receiving electromagnetic signals fed back by RFID tags at various locations under radio frequency signals, the Kalman filter algorithm is used to process the electromagnetic signals.
10. A method for monitoring coal seam thickness in a coal mill based on RFID check-in, as described in claim 8, characterized in that, When increasing or decreasing the loading force of the coal mill, a PID closed-loop control algorithm is used for control.