Scraper conveyer driving motor control method, control equipment and scraper conveyer

Abstract

A control method for a driving motor of a scraper conveyor comprises the following steps: a starting stage: adjusting torques and rotating speeds of two axial magnetic flux motors in real time to ensure that the two motors cooperatively output large torques and are stably started; in the normal operation stage, when the scraper conveyor reaches the rated rotating speed and the load is stable, if the range is exceeded, the current driving mode is kept, the output torque of the motor is adjusted to adapt to the load change, and whether the single-machine mode is switched or not is judged after the current fluctuation returns to the range; in the mode switching stage, if the obtained load exceeds 120% of the rated load of the single motor, dual-motor driving is recovered, and after the load falls back to the safety range, single-motor operation is switched back; in the shutdown stage, shutdown is completed after a shutdown instruction is received. The invention further provides control equipment and a scraper conveyor. The requirement for large torque during heavy-load starting of the scraper conveyor is met, meanwhile, single-motor driving is achieved during normal operation so as to reduce energy consumption, and switching between a double-motor starting mode and a single-motor operation mode is stable so as to adapt to different working conditions.

Description

Technical Field

[0001] This invention relates to the field of scraper conveyor technology, and in particular to a scraper conveyor drive motor control method, control equipment, and scraper conveyor. Background Technology

[0002] Scraper conveyors are key transportation equipment in fully mechanized coal mining faces, conveying materials through the cyclical movement of scraper chains within a chute. Traditional scraper conveyors mostly use AC asynchronous motors, which suffer from low efficiency and insufficient starting torque. Although some research has explored the application of permanent magnet synchronous motors, they still require significant power output to handle heavy-load starts, while power demands decrease during normal operation. Traditional drive methods struggle to balance starting performance with energy efficiency. Axial flux motors offer advantages such as high power density and high torque density, but are currently not used in scraper conveyors. Summary of the Invention

[0003] In order to solve the technical problems existing in the above-mentioned technologies, it is necessary to provide a control method for the drive motor of a scraper conveyor.

[0004] A method for controlling the drive motor of a scraper conveyor includes the following steps:

[0005] Step S1, Startup Phase:

[0006] Based on the real-time acquired torque and speed data, the torque and speed of the two axial flux motors are adjusted in real time to ensure that the two motors work together to output large torque and start smoothly.

[0007] Step S2, Normal Operation Phase:

[0008] When the scraper conveyor reaches its rated speed and the load is stable, the standard for load stability is that the fluctuation of the motor operating current does not exceed ±8% of the rated current. If it exceeds the range, the controller maintains the current drive mode and adapts to the load change by adjusting the motor output torque. It will determine whether to switch to single-machine mode after the current fluctuation returns to the range.

[0009] Step S3, Mode Switching Stage:

[0010] If the acquired load exceeds 120% of the rated load of a single motor, the electromagnetic clutch of the motor in standby mode will be engaged to restore dual-motor drive. Once the load drops to a safe range, the system will switch back to single-motor operation.

[0011] Step S4, Shutdown Phase:

[0012] Upon receiving a shutdown command, the system controls the motor in operation to reduce its output, causing the scraper chain to decelerate and stop. Then, it disengages the electromagnetic clutch to complete the shutdown process.

[0013] Preferably, in step S1, the specific process of the startup phase is as follows:

[0014] S11: Control the inverter to input low-voltage DC power to the two motors, so that the stator windings of the motors establish an initial magnetic field. At the same time, the speed encoder monitors the initial position of the motor rotor to prepare for precise start-up.

[0015] S12: The two motors output gradually increasing three-phase AC power to control the motors to start rotating from rest, with the initial output speed set at 50% of the rated speed;

[0016] S13: The torque sensor collects the output torque of the two motors in real time. The controller compares the two torque values ​​and sends an adjustment command to the inverter to ensure that the difference in output torque between the two motors is controlled within the set range.

[0017] S14: After the scraper chain of the scraper conveyor starts to move continuously, the control motor speed is gradually increased to 90% of the rated speed, while maintaining stable output torque to avoid unstable operation of the scraper chain due to speed fluctuations.

[0018] S15: When the motor speed stabilizes at the rated speed and runs continuously for 3-5 seconds, the start-up process is determined to be complete. At this time, according to the load monitoring results, if the load is within the normal range, preparations are made to switch to single-machine operation mode.

[0019] S16: If the load is still large, maintain the dual-machine drive state until the load drops back to the normal range.

[0020] Preferably, in step S13, the difference in output torque between the two motors is controlled within ±5% of the rated torque.

[0021] Preferably, if the torque difference exceeds ±5% of the rated torque, the controller will prioritize reducing the output of the motor with higher torque in steps of 2% of the rated torque per cycle; at the same time, it will monitor the change in torque difference, and if the difference still does not return to the range after 2-3 adjustment cycles, it will then attempt to slightly increase the output of the motor with lower torque.

[0022] Preferably, in step S13, the torque stability standard is that the output torque fluctuation does not exceed ±3% of the rated torque.

[0023] Preferably, the following operations are required before the startup phase.

[0024] Perform an initialization check on the axial flux motor and check the working status of the electromagnetic clutch to ensure that it is in an engaging state.

[0025] A signal is sent to the electromagnetic clutches corresponding to the two motors to activate them, thus engaging the output shafts of the two motors with the input terminals of their respective planetary reducers, thereby establishing a power transmission channel.

[0026] Preferably, in step S3, the load safety range is no more than 100% of the rated load of a single machine.

[0027] The preferred method for determining mode switching is as follows:

[0028] If the load exceeds this range but is ≤120%, it falls within the short-term allowable overload range for a single machine. Maintain single-machine operation and utilize the motor's own overload capacity to cope with small load fluctuations, avoiding increased energy consumption and equipment wear caused by frequent switching between two machines.

[0029] If the load is greater than 120%, the dual-machine drive mode will be activated immediately. At the same time, the controller will trigger an overload warning and limit the total output torque of the two machines to no more than 1.5 times the rated torque to prevent long-term over-torque from causing equipment damage such as overheating of the motor windings and demagnetization of the permanent magnets.

[0030] When the system is in dual-machine drive mode, and the load drops to below 90% of the single-machine rated load for 5 seconds, it will switch back to single-machine operation mode.

[0031] It is also necessary to provide a control device.

[0032] A control device includes a processor and a memory storing program instructions, wherein the processor calls the executable program code stored in the memory to execute the scraper conveyor drive motor control method described above.

[0033] It is also necessary to provide a scraper conveyor.

[0034] A scraper conveyor includes a scraper conveyor body and control equipment used in conjunction with the scraper conveyor body.

[0035] Compared with the prior art, the scraper conveyor drive motor control method provided by the present invention has the following advantages:

[0036] 1. In dual-motor start-up mode, two axial flux motors work together to output high torque. Their high torque density characteristics can quickly overcome the huge resistance when the scraper conveyor starts under heavy load. Compared with traditional single-motor start-up, the start-up time is significantly shortened, and the speed fluctuation during the start-up process is small. This effectively avoids problems such as scraper chain jamming and motor overload caused by insufficient start-up torque, ensuring that the equipment can still start smoothly under heavy load conditions and reducing the equipment failure rate during the start-up phase.

[0037] 2. During normal operation, the system switches to single-motor drive, fully utilizing the high efficiency of the axial flux motor. Compared to the traditional dual-motor continuous operation mode, energy consumption is significantly reduced. Simultaneously, single-motor operation reduces motor operating time and mechanical wear, extending motor lifespan and lowering equipment maintenance costs.

[0038] 3. The mode switching mechanism responds quickly, enabling timely handling of sudden heavy loads and preventing shutdown accidents caused by single-machine overload, thus ensuring continuous production in the fully mechanized mining face. The smooth switching between dual-machine start-up and single-machine operation allows the system to adapt to both the stringent requirements of heavy-load start-up and the energy-saving needs of normal operation. It maintains stable operation under varying coal seam thicknesses and mining speeds, enhancing the scraper conveyor's adaptability to complex underground environments. Attached Figure Description

[0039] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a flowchart illustrating the motor startup process of the present invention. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] In one embodiment, the present invention provides a method for controlling the drive motor of a scraper conveyor, comprising the following steps:

[0043] Step S1, Startup Phase:

[0044] Based on the real-time acquired torque and speed data, the torque and speed of the two axial flux motors are adjusted in real time to ensure that the two motors work together to output large torque and start smoothly.

[0045] Step S2, Normal Operation Phase:

[0046] When the scraper conveyor reaches its rated speed and the load is stable, the standard for load stability is that the fluctuation of the motor operating current does not exceed ±8% of the rated current. If it exceeds the range, the controller maintains the current drive mode and adapts to the load change by adjusting the motor output torque. It will determine whether to switch to single-machine mode after the current fluctuation returns to the range.

[0047] Step S3, Mode Switching Stage:

[0048] If the acquired load exceeds 120% of the rated load of a single motor, the electromagnetic clutch of the motor in standby mode will be engaged to restore dual-motor drive. Once the load drops to a safe range, the system will switch back to single-motor operation.

[0049] Step S4, Shutdown Phase:

[0050] Upon receiving a shutdown command, the system controls the motor in operation to reduce its output, causing the scraper chain to decelerate and stop. Then, it disengages the electromagnetic clutch to complete the shutdown process.

[0051] To elaborate in detail, the specific process of the startup phase in step S1 is as follows:

[0052] S11: Control the inverter to input low-voltage DC power to the two motors, so that the stator windings of the motors establish an initial magnetic field. At the same time, the speed encoder monitors the initial position of the motor rotor to prepare for precise start-up.

[0053] S12: The two motors output gradually increasing three-phase AC power to control the motors to start rotating from rest, with the initial output speed set at 50% of the rated speed;

[0054] S13: The torque sensor collects the output torque of the two motors in real time. The controller compares the two torque values ​​and sends an adjustment command to the inverter to ensure that the difference in output torque between the two motors is controlled within the set range.

[0055] S14: After the scraper chain of the scraper conveyor starts to move continuously, the control motor speed is gradually increased to 90% of the rated speed, while maintaining stable output torque to avoid unstable operation of the scraper chain due to speed fluctuations.

[0056] S15: When the motor speed stabilizes at the rated speed and runs continuously for 3-5 seconds, the start-up process is determined to be complete. At this time, according to the load monitoring results, if the load is within the normal range, preparations are made to switch to single-machine operation mode.

[0057] S16: If the load is still large, maintain the dual-machine drive state until the load drops back to the normal range.

[0058] Specifically, in step S13, the difference in output torque between the two motors is controlled within ±5% of the rated torque.

[0059] Correspondingly, if the torque difference exceeds ±5% of the rated torque, the controller will prioritize reducing the output of the motor with higher torque in steps of 2% of the rated torque per cycle; at the same time, it will monitor the change in torque difference, and if the difference still does not return to the range after 2-3 adjustment cycles, it will then attempt to slightly increase the output of the motor with lower torque.

[0060] Specifically, in step S13, the torque stability standard is that the output torque fluctuation does not exceed ±3% of the rated torque.

[0061] To elaborate further, the following steps are required before the startup phase.

[0062] Perform an initialization check on the axial flux motor and check the working status of the electromagnetic clutch to ensure that it is in an engaging state.

[0063] A signal is sent to the electromagnetic clutches corresponding to the two motors to activate them, thus engaging the output shafts of the two motors with the input terminals of their respective planetary reducers, thereby establishing a power transmission channel.

[0064] To elaborate in detail, in step S3, the load safety range is no more than 100% of the rated load of a single machine.

[0065] Specifically, the method for determining mode switching is as follows:

[0066] If the load exceeds this range but is ≤120%, it falls within the short-term allowable overload range for a single machine. Maintain single-machine operation and utilize the motor's own overload capacity to cope with small load fluctuations, avoiding increased energy consumption and equipment wear caused by frequent switching between two machines.

[0067] If the load is greater than 120%, the dual-machine drive mode will be activated immediately. At the same time, the controller will trigger an overload warning and limit the total output torque of the two machines to no more than 1.5 times the rated torque to prevent long-term over-torque from causing equipment damage such as overheating of the motor windings and demagnetization of the permanent magnets.

[0068] When the system is in dual-machine drive mode, and the load drops to below 90% of the single-machine rated load for 5 seconds, it will switch back to single-machine operation mode.

[0069] In one embodiment, the present invention provides a control device including a processor and a memory storing program instructions, wherein the processor calls the executable program code stored in the memory to execute the above-described scraper conveyor drive motor control method.

[0070] In one embodiment, the present invention provides a scraper conveyor, including a scraper conveyor body and a control device used in conjunction with the scraper conveyor body.

[0071] The above description discloses only preferred embodiments of the present invention and should not be construed as limiting the scope of the invention. Those skilled in the art will understand that implementing all or part of the above embodiments and making equivalent changes in accordance with the claims of the present invention are still within the scope of the invention.

Claims

1. A method for controlling the drive motor of a scraper conveyor, characterized in that: Includes the following steps, Step S1, Startup Phase: Based on the real-time acquired torque and speed data, the torque and speed of the two axial flux motors are adjusted in real time to ensure that the two motors work together to output large torque and start smoothly. Step S2, Normal Operation Phase: When the scraper conveyor reaches its rated speed and the load is stable, the standard for load stability is that the fluctuation of the motor operating current does not exceed ±8% of the rated current. If it exceeds the range, the controller maintains the current drive mode and adapts to the load change by adjusting the motor output torque. It will determine whether to switch to single-machine mode after the current fluctuation returns to the range. Step S3, Mode Switching Stage: If the acquired load exceeds 120% of the rated load of a single motor, the electromagnetic clutch of the motor in standby mode will be engaged to restore dual-motor drive. Once the load drops to a safe range, the system will switch back to single-motor operation. Step S4, Shutdown Phase: Upon receiving a shutdown command, the system controls the motor in operation to reduce its output, causing the scraper chain to decelerate and stop. Then, it disengages the electromagnetic clutch to complete the shutdown process.

2. The scraper conveyor drive motor control method according to claim 1, characterized in that: In step S1, the specific process of the startup phase is as follows: S11: Control the inverter to input low-voltage DC power to the two motors, so that the stator windings of the motors establish an initial magnetic field. At the same time, the speed encoder monitors the initial position of the motor rotor to prepare for precise start-up. S12: The two motors output gradually increasing three-phase AC power to control the motors to start rotating from rest, with the initial output speed set at 50% of the rated speed; S13: The torque sensor collects the output torque of the two motors in real time. The controller compares the two torque values ​​and sends an adjustment command to the inverter to ensure that the difference in output torque between the two motors is controlled within the set range. S14: After the scraper chain of the scraper conveyor starts to move continuously, the control motor speed is gradually increased to 90% of the rated speed, while maintaining stable output torque to avoid unstable operation of the scraper chain due to speed fluctuations. S15: When the motor speed stabilizes at the rated speed and runs continuously for 3-5 seconds, the start-up process is determined to be complete. At this time, according to the load monitoring results, if the load is within the normal range, preparations are made to switch to single-machine operation mode. S16: If the load is still large, maintain the dual-machine drive state until the load drops back to the normal range.

3. The scraper conveyor drive motor control method according to claim 2, characterized in that: In step S13, the difference in output torque between the two motors is controlled within ±5% of the rated torque.

4. The scraper conveyor drive motor control method according to claim 3, characterized in that: If the torque difference exceeds ±5% of the rated torque, the controller will prioritize reducing the output of the motor with higher torque in steps of 2% of the rated torque per cycle. At the same time, it will monitor the change in torque difference. If the difference does not return to the range after 2-3 adjustment cycles, it will then attempt to slightly increase the output of the motor with lower torque.

5. The scraper conveyor drive motor control method according to claim 4, characterized in that: In step S13, the torque stability standard is that the output torque fluctuation does not exceed ±3% of the rated torque.

6. The scraper conveyor drive motor control method according to claim 5, characterized in that: Before the startup phase, the following steps are required. Perform an initialization check on the axial flux motor and check the working status of the electromagnetic clutch to ensure that it is in an engaging state. A signal is sent to the electromagnetic clutches corresponding to the two motors to activate them, thus engaging the output shafts of the two motors with the input terminals of their respective planetary reducers, thereby establishing a power transmission channel.

7. The scraper conveyor drive motor control method according to claim 1 or 2, characterized in that: In step S3, the load safety range is no more than 100% of the rated load of a single machine.

8. The scraper conveyor drive motor control method according to claim 7, characterized in that: The specific mode switching determination method is as follows: If the load exceeds this range but is ≤120%, it falls within the short-term allowable overload range for a single machine. Maintain single-machine operation and utilize the motor's own overload capacity to cope with small load fluctuations, avoiding increased energy consumption and equipment wear caused by frequent switching between two machines. If the load is greater than 120%, the dual-machine drive mode will be activated immediately. At the same time, the controller will trigger an overload warning and limit the total output torque of the two machines to no more than 1.5 times the rated torque to prevent long-term over-torque from causing equipment damage such as overheating of the motor windings and demagnetization of the permanent magnets. When the system is in dual-machine drive mode, and the load drops to below 90% of the single-machine rated load for 5 seconds, it will switch back to single-machine operation mode.

9. A control device, characterized in that: The method includes a processor and a memory storing program instructions, wherein the processor calls the executable program code stored in the memory to execute the scraper conveyor drive motor control method according to any one of claims 1-8.

10. A scraper conveyor, characterized in that: It includes the scraper conveyor body and the control equipment used in conjunction with the scraper conveyor body.

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