An automatic detection and feeding device for biomass pellets and its control method

Abstract

This invention discloses an automatic biomass pellet detection and feeding device and its control method, including a storage silo and a feeding pipe; one end of the feeding pipe is inserted into the storage silo, and the other end is inserted into a feed bin; an auger is built into one end of the feeding pipe; the auger is connected to a feeding motor that drives its rotation, and the rotating auger sucks up biomass pellets through one end of the feeding pipe, and then discharges the biomass pellets into the feed bin through the other end of the feeding pipe; it also includes a level detector; the level detector is used to detect the material level in the feed bin, and the level detector is connected to a main control board, which is connected to the feeding motor; the main control board automatically controls the switching of the feeding motor according to the signal from the level detector. This invention is equipped with an auger to extract biomass pellets from the storage silo and discharge them into the feed bin; it also includes a level detector to detect the material level in the feed bin and automatically controls the switching of the auger according to the material level signal.

Description

Technical Field

[0001] This invention relates to the field of biomass pellet combustion technology, and in particular to an automatic biomass pellet detection and feeding device and its control method. Background Technology

[0002] Biomass pellet burners use cylindrical rods as fuel, typically 6-12mm in diameter and 40-100mm in length. The material is crushed pellets from wood, tobacco stalks, corn stalks, etc., which are then compressed into pellets. This low-pollution fuel is a viable alternative to coal and is widely used in tobacco curing. A biomass pellet burner is a device specifically designed to generate heat through the combustion of biomass pellets. The burner has a feed hopper that continuously supplies fuel to the combustion chamber to maintain the combustion and heating process. In tobacco curing, current feeding methods are generally manual, requiring 24-hour human supervision. Fuel needs to be replenished as needed, resulting in high labor intensity. Common feeding equipment, such as auger feeders, still require manual start-up and shutdown, failing to address the 24-hour human supervision issue. Furthermore, these feeders lack automatic support points, requiring manual alignment of the discharge port, and the feeding speed is slow compared to manual bag-filling. Therefore, they have not been widely adopted in actual production. Inventing an automatic feeding device that enables unattended operation has significant practical value. Summary of the Invention

[0003] In view of at least one deficiency of the prior art, the object of the present invention is to provide an automatic detection and feeding device for biomass pellets, which is equipped with an auger to extract biomass pellets from the storage bin and discharge them into a feed hopper; it is also equipped with a level detector to detect the level of the feed hopper and automatically control the switching of the auger according to the level signal.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: an automatic detection and feeding device for biomass pellets, comprising a storage silo and a feeding pipe; one end of the feeding pipe is inserted into the storage silo, and the other end of the feeding pipe is inserted into a feed bin; an auger is built into one end of the feeding pipe; the auger is connected to a feeding motor that drives its rotation, and the rotating auger sucks up biomass pellets through one end of the feeding pipe, and then discharges the biomass pellets into the feed bin through the other end of the feeding pipe; it also includes a level detector; the level detector is used to detect the level of material in the feed bin, and the level detector is connected to a main control board, which is connected to the feeding motor; the main control board automatically controls the switching of the feeding motor according to the signal from the level detector.

[0005] One end of the feed pipe is open to form the feed inlet, and the other end of the feed pipe is open to form the discharge outlet.

[0006] It also includes a discharge detector; the discharge detector is used to detect whether biomass particles are discharged from the other end of the feed pipe, and the discharge detector is connected to the main control board.

[0007] The feed pipe includes a front rigid pipe, a middle rigid pipe, and a terminal flexible pipe connected in sequence. The front and middle rigid pipes are made of rigid materials, while the terminal flexible pipe is made of soft material and can swing around the end of the middle rigid pipe. An auger is installed inside the front rigid pipe. The lower end of the front rigid pipe is inserted into the storage bin. The upper part of the front rigid pipe is connected to one end of the middle rigid pipe. The other end of the middle rigid pipe crosses the upper opening edge of the hopper and connects to the upper end of the terminal flexible pipe. The lower end of the terminal flexible pipe is inserted into the hopper.

[0008] A connection port is located near the top of the front rigid pipe, which connects to one end of the middle rigid pipe. The end flexible tube has moderate strength, allowing it to swing around the end of the middle rigid pipe without collapsing and affecting material discharge.

[0009] An attitude sensor is installed on the lower outer wall of the terminal hose. The attitude sensor is used to detect the angle of the discharge port at the lower end of the terminal hose. The attitude sensor is connected to the main control board. A discharge port angle adjustment motor is also fixedly installed on the middle rigid pipe. The output shaft of the discharge port angle adjustment motor is fixedly connected to one end of a rocker arm. The other end of the rocker arm is connected to the lower outer wall of the terminal hose through a pivot structure. The main control board controls the discharge port angle adjustment motor to rotate according to the signal from the attitude sensor. The discharge port angle adjustment motor drives the lower end of the terminal hose to swing through the rocker arm. A material level detector is installed on the lower outer wall of the terminal hose. The discharge detector is suspended on the lower outer wall of the terminal hose by a bracket. The discharge detector is close to the discharge port of the terminal hose.

[0010] The lower end of the front rigid pipe is opened to form a feed inlet. A guide wheel is also fixedly installed on the lower part of the front rigid pipe near its lower end. The guide wheel can roll on the inner wall of the storage bin. A counterweight is also fixedly installed on the lower outer wall of the front rigid pipe.

[0011] The main control board is equipped with a microcontroller, which is connected to the material level detector, the feed motor, the discharge detector, the attitude sensor, and the discharge port angle adjustment motor.

[0012] An automatic detection and feeding device for biomass pellets and its control method include the following steps:

[0013] Step A: The main control board detects the angle of the discharge port through the attitude sensor;

[0014] Step B: The main control board determines whether the discharge port is vertically downward. If not, proceed to step C; if yes, proceed to step D.

[0015] Step C: The main control board controls the rotation of the discharge port angle adjustment motor to make the discharge port vertically downward;

[0016] Step D: The main control board reads the data from the material level detector;

[0017] Step E: The main control board determines whether the data from the material level detector is greater than the maximum distance. If yes, proceed to step F; if no, wait for the data transmission cycle and proceed to step M.

[0018] Step F: The main control board controls the operation of the feed motor;

[0019] Step G: The main control board reads the data from the discharge detector;

[0020] Step H: The main control board determines whether the discharge port is discharging material. If not, it sets a material shortage fault flag and proceeds to step M; if yes, it proceeds to step I.

[0021] Step 1: The main control board accumulates the feeding time of the feeding motor;

[0022] Step J: The main control board calculates the distance change rate based on the signal from the level detector;

[0023] Step K: The main control board determines whether the speed is greater than or equal to the minimum speed. If yes, proceed to step L; if no, set the material shortage fault flag and proceed to step M.

[0024] Step L: The main control board determines whether the distance is less than the minimum distance. If not, proceed to step F; if yes, proceed to step M.

[0025] Step M: Send data including cumulative feeding time, cumulative material level rise, feeding motor status, estimated fuel consumption, and fault flags, then return to Step A.

[0026] The key to the control method of the automatic detection and feeding device for biomass pellets is that it includes a feeding speed calculation method and a fuel consumption calculation method.

[0027] Feeding speed calculation method: During the feeding motor power-on process, the value of the material level detector is collected in real time, and the rate of change of material level is calculated. If the rate of change of material level is lower than the lower limit threshold, the feeding speed is considered to be too low.

[0028] Fuel consumption calculation method: Real-time statistics of the cumulative feeding time and cumulative material level rise of the feeding motor; the cumulative material level rise refers to the amount of material level rise before and after each feeding process is collected and recorded, and then accumulated to obtain the cumulative material level rise value;

[0029] The volume of fuel consumed is calculated based on the theoretical feed rate, and then the theoretical weight m1 of the consumed fuel is calculated based on the fuel bulk density. The theoretical feed rate is related to the diameter of the feed pipe and the speed of the feed motor.

[0030] (1) A method for calculating the theoretical weight m1 of fuel consumed based on the cumulative feeding time;

[0031] The theoretical weight of fuel consumed, m1, = cumulative feeding time of the feed motor × auger rotation speed × diameter of the feed pipe × fuel bulk density × biomass pellet space occupancy coefficient;

[0032] The biomass pellet space occupancy factor refers to the volume factor used when biomass pellets, due to their irregular shape and gaps between them, do not completely fill the entire stockpile space during transportation. This data is obtained through experiments or mathematical estimation, and the biomass pellet space occupancy factor is taken as 0.32.

[0033] (2) A method for calculating the fuel consumption weight m2 based on the cumulative rise in material level;

[0034] Fuel consumption weight m2 = cumulative material level rise × cross-sectional area of ​​the hopper × biomass pellet space occupancy coefficient × fuel bulk density × stockpile shape coefficient;

[0035] The stockpile shape factor refers to the adjustment factor used when biomass pellets are stacked in the feed bin, where the surface is not flat and the pellets are approximately conical when feeding is just completed. This data is obtained through experiments or mathematical estimation, and the stockpile shape factor is taken as 0.55.

[0036] (3) Estimated fuel consumption;

[0037]

[0038] m is the estimated value of fuel consumption.

[0039] Significant effects: This invention provides an automatic biomass pellet detection and feeding device and its control method, which is equipped with an auger to extract biomass pellets from the storage bin and discharge them into a feed hopper; it is also equipped with a level detector to detect the level of the feed hopper and automatically control the auger to switch on and off based on the level signal. Attached Figure Description

[0040] Figure 1 This is a structural block diagram of the automatic detection and feeding device;

[0041] Figure 2 A simplified mechanical structure diagram of the automatic detection and feeding device;

[0042] Figure 3 This is a circuit structure block diagram of the present invention;

[0043] Figure 4 This is a structural diagram of the power module;

[0044] Figure 5 This is a structural diagram of a microcontroller;

[0045] Figure 6 This is the circuit diagram for the level sensor interface;

[0046] Figure 7 Circuit diagram for the output detection sensor interface;

[0047] Figure 8 Circuit diagram for the discharge port adjustment interface;

[0048] Figure 9 This is a circuit diagram of the attitude sensor interface;

[0049] Figure 10 This is the circuit diagram for the communication module;

[0050] Figure 11 This is the circuit diagram for the SIM card slot.

[0051] Figure 12 This is a flowchart of the process of the present invention. Detailed Implementation

[0052] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0053] like Figures 1-12 As shown, an automatic biomass pellet detection and feeding device includes a storage silo 1 and a feeding pipe 2. One end of the feeding pipe 2 is inserted into the storage silo 1, and the other end is inserted into a feed bin 3. An auger 4 is built into one end of the feeding pipe 2. The auger 4 is connected to a feeding motor 5 that drives its rotation. The rotating auger 4 sucks up biomass pellets 7 through one end of the feeding pipe 2, and then discharges the biomass pellets 7 into the feed bin 3 through the other end of the feeding pipe 2. The device also includes a level detector 6. The level detector 6 is used to detect the level of biomass pellets in the feed bin 3. The level detector 6 is connected to a main control board, which is connected to the feeding motor 5. The main control board automatically controls the switching of the feeding motor 5 based on the signal from the level detector 6. The main control board is equipped with a microcontroller.

[0054] One end of the feeding pipe 2 is open to form a feeding port, and the other end of the feeding pipe 2 is open to form a discharging port. When the microcontroller detects that the material level in the material box 3 is low through the material level detector 6, it controls the feeding motor 5 to be powered on to feed the material box 3; when the microcontroller detects that the material level in the material box 3 is high through the material level detector 6, it controls the feeding motor 5 to be powered off to stop feeding the material box 3.

[0055] It also includes a discharge detector 8; the discharge detector 8 is used to detect whether biomass pellets are discharged from the other end of the feed pipe 2, and the discharge detector 8 is connected to the main control board. When biomass pellets pass through the discharge detector 8, the discharge detector 8 detects the discharge signal and sends the discharge signal to the microcontroller; when no biomass pellets pass through the discharge detector 8, the discharge detector 8 does not detect the discharge signal.

[0056] The feed pipe 2 includes a front rigid pipe 21, a middle rigid pipe 22, and a terminal flexible pipe 23 connected in sequence. The front rigid pipe 21 and the middle rigid pipe 22 are made of rigid materials, and the terminal flexible pipe 23 is made of soft material and can swing around the end of the middle rigid pipe 22. The auger 4 is installed inside the front rigid pipe 21. The lower end of the front rigid pipe 21 is inserted into the storage bin 1. The upper part of the front rigid pipe 21 is connected to one end of the middle rigid pipe 22. The other end of the middle rigid pipe 22 crosses the upper opening edge of the material box 3 and is connected to the upper end of the terminal flexible pipe 23. The lower end of the terminal flexible pipe 23 is inserted into the material box 3.

[0057] Using the above structure, the biomass pellets extracted by the auger 4 enter the terminal hose 23 through the middle rigid pipe 22, and are discharged into the feed box 3 from the discharge port at the lower end of the terminal hose 23.

[0058] A connection port is located near the upper end of the front rigid tube 21, connecting to one end of the middle rigid tube 22. The end flexible tube 23 has moderate strength, allowing it to swing around the end of the middle rigid tube 22 without collapsing and affecting material discharge; a rubber tube or similar material can be used. A drive shaft is located at the upper end of the auger 4. After passing through a through hole at the upper end of the front rigid tube 21, a driven gear is fixedly fitted onto the drive shaft. The feed motor 5 is fixedly mounted on the upper part of the front rigid tube 21, and a drive gear that meshes with the driven gear is fixedly fitted onto the output shaft of the feed motor 5. Through this structure, the feed motor 5 can drive the auger 4 to rotate.

[0059] An attitude sensor 9 is installed on the lower outer wall of the terminal hose 23. The attitude sensor 9 is used to detect the angle of the discharge port at the lower end of the terminal hose 23. The attitude sensor 9 is connected to the main control board. A discharge port angle adjustment motor 10 is also fixedly installed on the middle rigid pipe 22. The output shaft of the discharge port angle adjustment motor 10 is fixedly connected to one end of the rocker arm 11. The other end of the rocker arm 11 is connected to the lower outer wall of the terminal hose 23 through a pivot structure. The main control board controls the discharge port angle adjustment motor 10 to rotate according to the signal of the attitude sensor 9. The discharge port angle adjustment motor 10 drives the lower end of the terminal hose 23 to swing through the rocker arm 11. The material level detector 6 is installed on the lower outer wall of the terminal hose 23. The discharge detector 8 is suspended on the lower outer wall of the terminal hose 23 by a bracket. The discharge detector 8 is close to the discharge port of the terminal hose 23.

[0060] Since the angle change of the discharge port at the lower end of the end hose 23 affects the detection accuracy of the level detector 6, an attitude sensor 9 is installed on the outer wall of the lower end of the end hose 23. The attitude sensor 9 is used to detect the angle of the discharge port at the lower end of the end hose 23. When the discharge port at the lower end of the end hose 23 is not vertically downward, the microcontroller controls the discharge port angle adjustment motor 10 to rotate. The discharge port angle adjustment motor 10 drives the lower end of the end hose 23 to swing through the rocker arm 11, so that the discharge port at the lower end of the end hose 23 is vertically downward, thereby improving the detection accuracy of the level detector 6.

[0061] The aforementioned structure eliminates the need for supports in the entire feed pipe 2, allowing it to be placed directly on the material box 3 and storage bin 1, thus simplifying the installation process.

[0062] The bottom of the middle section rigid pipe 22 is also fixed with a base plate. The middle section rigid pipe 22 is supported on the upper opening edge of the material box 3 by the base plate. The base plate prevents the middle section rigid pipe 22 from swinging back and forth. (Figure omitted)

[0063] The lower end of the front rigid pipe 21 is opened to form a feed inlet. A guide wheel 12 is also fixedly installed on the lower part of the front rigid pipe 21 near its lower end. The guide wheel 12 can roll on the inner wall of the storage bin 1. A counterweight 13 is also fixedly installed on the lower outer wall of the front rigid pipe 21.

[0064] As the feeding motor 5 rotates and vibrates, the lower end of the front rigid tube 21 gradually slides down to the bottom of the storage bin 1 with the assistance of the guide wheel 12. The counterweight 13 increases the weight of the lower end of the front rigid tube 21, making it easier for the lower end of the front rigid tube 21 to fall.

[0065] The main control board is equipped with a microcontroller, which is connected to the material level detector 6, the feeding motor 5, the discharge detector 8, the attitude sensor 9, and the discharge port angle adjustment motor 10.

[0066] Figure 4 This is a structural diagram of the power supply module; the power supply module supplies power to the microcontroller.

[0067] Figure 5 This is a structural diagram of a microcontroller; the microcontroller used is an STM8S003F3P6 microcontroller.

[0068] Figure 6 The circuit diagram shows the interface of the level sensor. The microcontroller connects to the level detector 6 through the level sensor interface. The level detector 6 can be an ultrasonic ranging sensor or an infrared ranging sensor.

[0069] Figure 7 The circuit diagram is for the discharge detection sensor interface; the microcontroller is connected to the discharge detector 8 through the discharge detection sensor interface. The discharge detector 8 can be an infrared diffuse reflection material detection sensor or a proximity sensor, or a combination of light-emitting diode and phototransistor, etc.

[0070] Figure 8 The circuit diagram is for the discharge port adjustment interface; the microcontroller connects to the discharge port angle adjustment motor 10 through the discharge port adjustment interface and controls the rotation of the discharge port angle adjustment motor 10 by outputting a PWM signal.

[0071] The microcontroller drives the feed motor 5 to rotate through the motor drive module (illustration omitted). The feed motor 5 can be a stepper motor.

[0072] Figure 9This is the circuit diagram for the attitude sensor interface; the microcontroller connects to attitude sensor 9 through the attitude sensor interface, and attitude sensor 9 is a triaxial gravity acceleration sensor.

[0073] Figure 10 This is the circuit diagram for the communication module; the microcontroller is connected to the communication module, and the microcontroller wirelessly connects to the server platform through the communication module.

[0074] Figure 11 This is a circuit diagram of the SIM card slot; the communication module is connected to the SIM card slot.

[0075] like Figure 12 As shown, an automatic biomass pellet detection and feeding device and its control method include the following steps:

[0076] Step A: The main control board detects the angle of the discharge port through attitude sensor 9;

[0077] Step B: The main control board determines whether the discharge port is vertically downward. If not, proceed to step C; if yes, proceed to step D.

[0078] Step C: The main control board controls the discharge port angle adjustment motor 10 to rotate, so that the discharge port is vertically downward;

[0079] Step D: The main control board reads the data from the level detector 6;

[0080] Step E: The main control board determines whether the data of the material level detector 6 is greater than the maximum distance. If yes, proceed to step F; if no, wait for the data transmission cycle and proceed to step M.

[0081] Here, a distance greater than the maximum distance indicates that the material bin 3 is short of material and needs to be replenished by the feeding motor 5; a distance less than or equal to the maximum distance indicates that the material bin 3 is not short of material; the data transmission cycle is to send data at certain intervals, such as once every 10 seconds or 1 minute.

[0082] Step F: The main control board controls the operation of the feed motor 5;

[0083] Step G: The main control board reads the data from the discharge detector 8;

[0084] Step H: The main control board determines whether the discharge port is discharging material. If not, it sets a material shortage fault flag and proceeds to step M; if yes, it proceeds to step I.

[0085] Step 1: The main control board accumulates the feeding time of the feeding motor 5;

[0086] Step J: The main control board calculates the distance change rate based on the signal from the level detector 6;

[0087] Step K: The main control board determines whether the speed is greater than or equal to the minimum speed. If yes, proceed to step L; if no, set the material shortage fault flag and proceed to step M.

[0088] Step L: The main control board determines whether the distance is less than the minimum distance. If not, proceed to step F; if yes, proceed to step M.

[0089] Step M: Send data including cumulative feeding time, cumulative material level rise, feeding motor status, estimated fuel consumption, and fault flags, then return to Step A.

[0090] The key to the control method of the automatic detection and feeding device for biomass pellets is that it includes a feeding speed calculation method and a fuel consumption calculation method.

[0091] Feeding speed calculation method: During the process of feeding motor 5 being powered on, the value of material level detector 6 is collected in real time, and the rate of change of material level is calculated. If the rate of change of material level is lower than the lower limit threshold, the feeding speed is considered to be too low.

[0092] Fuel consumption calculation method: Real-time statistics of the cumulative feeding time and cumulative material level rise of the feeding motor 5; the cumulative material level rise refers to the amount of material level rise before and after each feeding process is collected and recorded, and then accumulated to obtain the cumulative material level rise value;

[0093] The volume of fuel consumed is calculated based on the theoretical feed rate, and the theoretical weight m1 of the fuel consumed is calculated based on the fuel bulk density. The theoretical feed rate is related to the diameter of the feed pipe 2 and the speed of the feed motor 5.

[0094] (1) A method for calculating the theoretical weight m1 of fuel consumed based on the cumulative feeding time;

[0095] The theoretical weight of fuel consumed, m1, = cumulative feeding time of feed motor 5 × rotational speed of auger 4 × diameter of feed pipe 2 × fuel bulk density × biomass pellet space occupancy coefficient.

[0096] The biomass pellet space occupancy factor refers to the volume factor used when biomass pellets, due to their irregular shape and gaps between them, do not completely fill the entire stockpile space during transportation. This data is obtained through experiments or mathematical estimation, and the biomass pellet space occupancy factor is taken as 0.32.

[0097] (2) A method for calculating the fuel consumption weight m2 based on the cumulative rise in material level;

[0098] Fuel consumption weight m2 = cumulative material level rise × cross-sectional area of ​​material box 3 × biomass pellet space occupancy coefficient × fuel bulk density × material pile shape coefficient;

[0099] The stockpile shape factor refers to the adjustment factor used when biomass pellets are stacked in the feed bin 3, where the surface is not flat and the pellets are approximately conical when feeding is just completed. This data is obtained through experiments or mathematical estimation, and the stockpile shape factor is taken as 0.55.

[0100] (3) Estimated fuel consumption;

[0101]

[0102] m is the estimated value of fuel consumption.

[0103] 0.33 and 0.22 are both fuel weight estimation coefficients;

[0104] 1. The coefficients in the formula for calculating m were obtained through experimental measurements using different fuel specifications and the specifications of the feed box 3; 2. It was found in the experiment that the error of m2 is smaller than that of m1, with a ratio of approximately 2:3; 3. Because m2 is more accurate, m is used as the basis for calculating m; when m1 = m2, the coefficient is 1, that is, m = m2.

[0105] This device has the following advantages:

[0106] (1) Easy to install and use. It works automatically when powered on, without the need to install auxiliary sensors on the burner. It automatically detects whether the material bin 3 is low on material and automatically adds material.

[0107] (2) Automatically determine whether the storage bin 1 is short of material and send a material shortage alarm message. When material is short, the discharge detector 8 will not detect the signal of biomass pellets passing by.

[0108] (3) The feeding time of the feeding motor 5 is automatically counted to assist in the calculation of fuel consumption.

[0109] (4) Automatically determine the direction of the discharge port and adjust it to be vertically downward, which improves the monitoring accuracy of the fuel quantity in the material box 3.

[0110] (5) Automatically calculate the feeding speed and judge whether the feeding speed is reasonable based on the relationship between the change rate of material displacement and the feeding time.

[0111] (6) Install a fuel monitoring sensor, namely the discharge detector 8, at the discharge port. If no fuel is detected falling, it is considered that the storage bin 1 is short of material or the feeding equipment is faulty.

[0112] The components of this device are:

[0113] The device automatically detects whether the feed bin 3 is low on material. If so, it powers the feeding motor 5, allowing the biomass pellets inside the storage bin 1 to enter the feed bin 3 through the feeding pipe 2 until the set material level is reached. Storage bin 1: Its structural feature is that the inclination angle of the bin wall is the same as that of the feeding pipe 2, which helps to fix the inclination angle of the feeding pipe 2. Storage bin 1 has a large opening at the top and a small bottom. The flat bottom area is slightly larger than the area occupied by the inlet of the feeding pipe 2 and the guide wheel 12, facilitating the automatic sliding of the feeding pipe 2 and guide wheel 12 to the bottom of storage bin 1. It also fully utilizes the storage bin's volume, conveying pellets from the bottom of the bin to the feed bin.

[0114] Guide wheel 12: The end of the feed pipe 2 is provided with a guide wheel 12, which is used to enable the feed pipe 2 to roll at the bottom of the storage bin 1, so as to facilitate the adjustment of the tilt angle.

[0115] Automatic guiding method for feed pipe 2: During the feeding process, the feed motor 5 drives the auger 4 inside the feed pipe 2 to rotate, which will cause the feed pipe 2 to vibrate. During the vibration, the feed pipe 2 will gradually sink to the bottom of the storage bin 1. The inclination angle of the inner wall of the storage bin 1 is consistent with the target inclination angle of the feed pipe 2. Under the action of the guide wheel 12, the guide wheel 12 will eventually sink to the bottom of the storage bin 1.

[0116] Counterweight 13: Its function is to increase the mass of the bottom of the feed pipe 2, and accelerate the sinking of the feed pipe 2 into the bottom of the storage bin 1 during the vibration of the feeding process.

[0117] Discharge Detector 8: Its function is to detect whether biomass pellets are passing through the discharge port. That is, if no biomass pellets pass through the discharge port when the feed motor 5 is energized, it may be that the storage silo 1 is short of material or the device is malfunctioning, and an audible and visual alarm signal will be issued. The detection method is to set a proximity switch at the discharge port. When no biomass pellets flow through the discharge port, the proximity switch outputs a low level, and when biomass pellets flow through the discharge port, the proximity switch outputs a high level.

[0118] Attitude sensor 9: measures the angle of the discharge port.

[0119] Discharge port angle adjustment motor 10: In order to ensure that the discharge port is perpendicular to the horizontal plane, a servo motor is installed at the upper end of the discharge port pipe, i.e., the end hose 23, and an attitude sensor 9 is installed on the discharge port pipe. The control board reads the tilt angle of the discharge port, adjusts the servo motor, and automatically adjusts the angle of the discharge port.

[0120] Material level detector 6: Its function is to detect the distance between the material level surface in the material bin 3 and the discharge port. If the distance exceeds a certain value, such as 30cm, it is considered that there is a shortage of material. If the distance is less than a certain value, such as 5cm, it is considered that the material is full.

[0121] Feeding speed calculation method: During the process of feeding motor 5 being powered on, the value of material level detector 6 is collected in real time to calculate the rate of change of material level. If the rate of change of material level is lower than a certain value, such as the material level change per minute being less than 5cm, the feeding speed is considered to be too low, which may be due to faults such as material blockage inside the device.

[0122] Fuel consumption calculation method: After the device is powered on, the following are counted in real time: (1) the cumulative feeding time of the feed motor 5 and (2) the cumulative material level rise. The cumulative material level rise refers to the accumulation of the material level rise before and after each feeding process. Based on the theoretical feeding speed (determined by the diameter of the feed pipe 2 and the speed of the feed motor 5), the volume of fuel consumed is calculated. Then, based on the fuel volume density, the theoretical weight m1 of the fuel consumed is calculated.

[0123] (1) A method for calculating the theoretical weight of fuel consumption m1 based on the cumulative feeding time;

[0124] The cumulative theoretical weight of fuel consumed m1 = cumulative feeding time of feed motor 5 × rotation speed of screw conveyor 4 × diameter of feed pipe 2 × fuel bulk density × biomass pellet space occupancy coefficient;

[0125] The space occupancy factor of biomass pellets is determined by the fact that biomass pellets are irregularly shaped and have gaps between them. During pipeline transportation, they do not completely fill the entire space. This data is obtained through experiments or mathematical estimation, and here we take 0.32.

[0126] (2) A method for calculating fuel consumption based on the cumulative rise in material level;

[0127] The cumulative fuel consumption weight m2 = cumulative material level rise × cross-sectional area of ​​hopper 3 × biomass pellet space occupancy coefficient × fuel bulk density × stockpile shape coefficient;

[0128] The stockpile shape factor is determined by the fact that when biomass pellets are stacked in feed bin 3, the surface is not flat and is approximately conical when feeding is just completed. This data is obtained through experiments or mathematical estimation, and here we take 0.55.

[0129] (3) Fuel consumption estimate

[0130] Since biomass pellets come in various shapes and sizes in practical applications, the biomass pellet space occupancy factor and the stockpile shape factor also vary. By determining the shape of the biomass pellets based on the difference between the two calculation methods mentioned above, and by correcting the biomass pellet space occupancy factor and the stockpile shape factor, the accuracy of fuel consumption estimation can be improved.

[0131] m1: The cumulative weight of fuel consumed (1);

[0132] m2: The total weight of fuel consumed (2);

[0133] (3) Estimated fuel consumption;

[0134]

[0135] m is the estimated value of fuel consumption.

[0136] Equipment signal interruption alarm: The equipment periodically or after each feeding (when the material is full) sends data to the server platform, including the operating status of the feeding motor 5, the cumulative operating time of the feeding motor 5, the fault status, the cumulative fuel consumption, and the cumulative material level rise. If the server platform does not receive the data sent by the device for a certain period of time, such as more than 2 hours, it assumes that the equipment has malfunctioned or lost power, and the server platform automatically sends an alarm message to the management personnel.

[0137] The workflow of this invention is shown in the appendix. Figure 12 .

[0138] This invention has the following advantages: Without modifying the biomass burner's feed hopper 3, it achieves automatic detection of insufficient and full feed in the biomass pellet burner, automatically adding feed in the case of insufficient feed. All detection is handled by the feeding device itself, automatically adjusting the angle of the feeding pipe 2, judging whether the feeding speed is reasonable, determining whether the storage hopper 1 is low on feed and sending an alarm message, calculating the weight of consumed fuel and estimating whether combustion is normal (if feed is insufficient, combustion will be abnormal), and tracking the feeding time of the feeding motor 5 and estimating the cumulative feed amount. The equipment is easy to install and use. If the server platform does not receive data, it sends a signal interruption alarm message to the administrator, indicating a possible power outage or a malfunction in the feeding equipment.

[0139] Finally, it should be noted that the above are only specific embodiments of the present invention. Of course, those skilled in the art can make modifications and variations to the present invention. If these modifications and variations fall within the scope of the claims of the present invention and their equivalents, they should be considered as being within the protection scope of the present invention.

Claims

1. An automatic detection and feeding device for biomass pellets, characterized in that, It includes a storage bin (1) and a feeding pipe (2); one end of the feeding pipe (2) is inserted into the storage bin (1), and the other end of the feeding pipe (2) is inserted into the material box (3); an auger (4) is built into one end of the feeding pipe (2); the auger (4) is connected to a feeding motor (5) that drives it to rotate, and the auger (4) rotates to suck up biomass pellets (7) through one end of the feeding pipe (2), and then discharges the biomass pellets (7) into the material box (3) through the other end of the feeding pipe (2); it also includes a level detector (6); the level detector (6) is used to detect the level of material in the material box (3), and the level detector (6) is connected to a main control board, which is connected to the feeding motor (5); The main control board automatically controls the switching of the feeding motor (5) based on the signal from the material level detector (6); The main control board is used to collect the value of the material level detector (6) in real time and calculate the rate of change of the material level. If the rate of change of the material level is lower than the lower limit threshold, the feeding speed is considered to be too low. The main control board is also used to calculate the cumulative feeding time and cumulative material level rise of the feeding motor (5) in real time; The cumulative material level rise refers to the amount of material level rise collected and recorded before and after each feeding process, and then accumulated to obtain the cumulative material level rise value. The volume of fuel consumed is calculated based on the theoretical feed rate, and the theoretical weight m1 of the consumed fuel is calculated based on the fuel bulk density. (1) The expression for calculating the theoretical weight m1 of fuel consumed based on the cumulative feeding time is: The theoretical weight of fuel consumed, m1, is calculated as follows: Cumulative feeding time of the feed motor (5) × Rotation speed of the auger (4) × Diameter of the feed pipe (2) × Fuel volume density × Biomass pellet space occupancy coefficient. The biomass pellet space occupancy factor refers to the volume factor used because biomass pellets are irregularly shaped and have gaps between them, and do not completely fill the entire stockpile space during transportation. (2) The expression for calculating the fuel consumption weight m2 based on the cumulative rise in material level is as follows: Fuel consumption weight m2 = cumulative material level rise × cross-sectional area of ​​material box (3) × biomass pellet space occupancy coefficient × fuel volume density × material pile shape coefficient; The stockpile shape coefficient refers to the adjustment coefficient used when the surface of the biomass pellets is not flat when they are piled in the feed box (3) and are approximately conical when the feeding is just completed. (3) Estimated fuel consumption; m is the estimated value of fuel consumption.

2. The automatic detection and feeding device for biomass pellets according to claim 1, characterized in that: It also includes a discharge detector (8); the discharge detector (8) is used to detect whether biomass particles are discharged from the other end of the feed pipe (2), and the discharge detector (8) is connected to the main control board.

3. The automatic detection and feeding device for biomass pellets according to claim 2, characterized in that: The feed pipe (2) includes a front section rigid pipe (21), a middle section rigid pipe (22), and a terminal section flexible pipe (23) connected in sequence. The front section rigid pipe (21) and the middle section rigid pipe (22) are made of rigid materials, and the terminal section flexible pipe (23) is made of soft materials and can swing around the end of the middle section rigid pipe (22). The auger (4) is installed in the front section rigid pipe (21). The lower end of the front section rigid pipe (21) is inserted into the storage bin (1). The upper part of the front section rigid pipe (21) is connected to one end of the middle section rigid pipe (22). The other end of the middle section rigid pipe (22) crosses the upper opening edge of the material box (3) and is connected to the upper end of the terminal section flexible pipe (23). The lower end of the terminal section flexible pipe (23) is inserted into the material box (3).

4. The automatic detection and feeding device for biomass pellets according to claim 3, characterized in that: An attitude sensor (9) is installed on the lower outer wall of the end hose (23). The attitude sensor (9) is used to detect the angle of the discharge port at the lower end of the end hose (23). The attitude sensor (9) is connected to the main control board. A discharge port angle adjustment motor (10) is also fixedly installed on the middle section hard pipe (22). The output shaft of the discharge port angle adjustment motor (10) is fixedly connected to one end of the rocker arm (11). The other end of the rocker arm (11) is connected to the lower outer wall of the end hose (23) through a pivot structure. The main control board controls the discharge port angle adjustment motor (10) to rotate according to the signal of the attitude sensor (9). The discharge port angle adjustment motor (10) drives the lower end of the end hose (23) to swing through the rocker arm (11). The material level detector (6) is installed on the lower outer wall of the end hose (23). The discharge detector (8) is suspended on the lower outer wall of the end hose (23) through a bracket. The discharge detector (8) is close to the discharge port of the end hose (23).

5. The automatic detection and feeding device for biomass pellets according to claim 3, characterized in that: The lower end of the front rigid pipe (21) is opened to form a feed inlet. A guide wheel (12) is fixedly installed on the lower part of the front rigid pipe (21) near its lower end. The guide wheel (12) can roll on the inner wall of the storage bin (1). A counterweight (13) is also fixedly installed on the lower outer wall of the front rigid pipe (21).

6. The control method for an automatic biomass pellet detection and feeding device according to claim 4, characterized in that, Includes the following steps: Step A: The main control board detects the outlet angle through the attitude sensor (9); Step B: The main control board determines whether the discharge port is vertically downward. If not, proceed to step C; if yes, proceed to step D. Step C: The main control board controls the discharge port angle adjustment motor (10) to rotate, so that the discharge port is vertically downward; Step D: The main control board reads the data from the level detector (6); Step E: The main control board determines whether the data of the material level detector (6) is greater than the maximum distance. If yes, proceed to step F; if no, wait for the data transmission cycle and proceed to step M. Step F: The main control board controls the operation of the feed motor (5); Step G: The main control board reads the data from the discharge detector (8); Step H: The main control board determines whether the discharge port is discharging material. If not, it sets a material shortage fault flag and proceeds to step M. If so, proceed to step I; Step 1: The main control board accumulates the feeding time of the feeding motor (5); Step J: The main control board calculates the distance change rate based on the signal from the level detector (6); Step K: The main control board determines whether the speed is greater than or equal to the minimum speed. If yes, proceed to step L; otherwise, set the material shortage fault flag and proceed to step M. Step L: The main control board determines whether the distance is less than the minimum distance. If not, proceed to step F. If so, proceed to step M; Step M: Send data including cumulative feeding time, cumulative material level rise, feeding motor status, estimated fuel consumption, and fault flags, then return to step A; It also includes methods for calculating feed rate and fuel consumption; Feeding speed calculation method: During the process of powering on the feeding motor (5), the value of the material level detector (6) is collected in real time, and the material level change rate is calculated. If the material level change rate is lower than the lower limit threshold, the feeding speed is considered to be too low. Fuel consumption calculation method: Real-time statistics of the cumulative feeding time and cumulative material level rise of the feeding motor (5); The cumulative material level rise refers to the amount of material level rise collected and recorded before and after each feeding process, and then accumulated to obtain the cumulative material level rise value. The volume of fuel consumed is calculated based on the theoretical feed rate, and the theoretical weight m1 of the consumed fuel is calculated based on the fuel bulk density. (1) A method for calculating the theoretical weight m1 of fuel consumed based on the cumulative feeding time; The theoretical weight of fuel consumed, m1, is calculated as follows: Cumulative feeding time of the feed motor (5) × Rotation speed of the auger (4) × Diameter of the feed pipe (2) × Fuel volume density × Biomass pellet space occupancy coefficient. The biomass pellet space occupancy factor refers to the volume factor used because biomass pellets are irregularly shaped and have gaps between them, and do not completely fill the entire stockpile space during transportation. (2) A method for calculating the fuel consumption weight m2 based on the cumulative rise in material level; Fuel consumption weight m2 = cumulative material level rise × cross-sectional area of ​​material box (3) × biomass pellet space occupancy coefficient × fuel volume density × material pile shape coefficient; The stockpile shape coefficient refers to the adjustment coefficient used when the surface of the biomass pellets is not flat when they are piled in the feed box (3) and are approximately conical when the feeding is just completed. (3) Estimated fuel consumption; m is the estimated value of fuel consumption.

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