Cutting machine power-off control method, equipment and program product

Abstract

The invention discloses a cutting machine power-off control method and device, a program product and a storage medium, and is applied to the technical field of fault protection. The method comprises the steps that in the operation process of a cutting machine, the speed of a virtual main shaft is configured as the main speed; for any motor participating in wire net motion control, the target speed of the motor is determined based on the main speed and the speed following proportion of the motor, and the speed of the motor is controlled based on the target speed of the motor; when it is detected that the cutting machine is powered off, the target voltage of the direct-current bus is obtained; and reducing the main speed to a preset threshold value, and in the reducing process, taking the fact that the actual voltage of the direct-current bus is equal to the target voltage as a target of feedback control, and adjusting the deceleration of the main speed. By means of the scheme, the situation that the wire net is broken when the cutting machine is powered off can be avoided.

Description

Technical Field

[0001] This invention relates to the field of fault protection technology, and in particular to a power-off control method, device and program product for a cutting machine. Background Technology

[0002] When there is a normal power supply, the multi-wire cutting machine can perform high-speed and stable cutting. However, when there is a power outage or abnormal power failure, all the motor shafts that control the high-speed operation of the wire network will stop due to the lack of power supply and will not be able to work together, resulting in the wire network of the multi-wire cutting machine breaking.

[0003] After the wire mesh breaks, the high-tension wire mesh wrapped around the guide rollers will instantly loosen and tangle together. Cleaning up these tangled wires is a very tedious and time-consuming process. Then, a series of complex preparations, including re-threading, rewinding, and tension calibration, must be performed, which takes a very long time and severely reduces the utilization rate of the equipment. Furthermore, the enormous energy released when the wire mesh breaks can impact and damage the precision guide rollers and main rollers, reducing the accuracy and lifespan of related components. At the moment of breakage, the workpiece being cut may be jammed or subjected to irregular impacts, rendering the entire workpiece unusable.

[0004] In conclusion, how to effectively deal with power outages in cutting machines and reduce losses is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a power failure control method, device, and program product for cutting machines, so as to effectively deal with power failures of cutting machines and reduce losses.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] In a first aspect, the present invention provides a cutting machine power supply system with an emergency power supply that provides power when the cutting machine is powered off, and a cutting machine power failure control method including: configuring the speed of the virtual spindle as the main speed during the operation of the cutting machine;

[0008] For any motor participating in the wire mesh motion control, the target speed of the motor is determined based on the main speed and the speed following ratio of the motor, and the speed control of the motor is performed based on the target speed of the motor.

[0009] When a power outage is detected in the cutting machine, the target voltage of the DC bus is acquired;

[0010] The main speed is reduced to a preset threshold, and during the reduction process, the actual voltage of the DC bus is equal to the target voltage as the target of feedback control, and the magnitude of the deceleration of the main speed is adjusted.

[0011] In one implementation, the main speed is reduced to a preset threshold, and during the reduction process, the actual voltage of the DC bus is equal to the target voltage as the target for feedback control, and the magnitude of the deceleration of the main speed is adjusted, including:

[0012] The main speed is reduced to a preset threshold, and during the reduction process, when the actual voltage of the DC bus is greater than the target voltage, the deceleration of the main speed is reduced, and when the actual voltage of the DC bus is less than the target voltage, the deceleration of the main speed is increased.

[0013] In one embodiment, the main speed is reduced to a preset threshold, and during the reduction process, when the actual voltage of the DC bus is greater than the target voltage, the deceleration of the main speed is reduced; when the actual voltage of the DC bus is less than the target voltage, the deceleration of the main speed is increased, including:

[0014] The main speed is reduced to a preset threshold, and during the reduction process, the difference between the target voltage and the actual voltage of the DC bus is used as the current voltage error value.

[0015] Based on the voltage error value and the closed-loop feedback algorithm, the current change in deceleration is obtained;

[0016] The current deceleration magnitude of the main velocity is obtained by superimposing the default value of the deceleration with the current change value of the deceleration.

[0017] In one implementation, it further includes:

[0018] Determine whether the current voltage error value does not exceed the preset first value range;

[0019] If so, replace the current voltage error value with 0.

[0020] In one implementation, it further includes:

[0021] Obtain the numerical adjustment range of the deceleration;

[0022] Adjusting the magnitude of the deceleration of the main velocity includes:

[0023] The magnitude of the deceleration of the main speed is adjusted according to the rule that the deceleration of the main speed does not exceed the numerical adjustment range.

[0024] In one embodiment, the emergency power supply of the cutting machine power supply system includes a first energy storage device and a second energy storage device.

[0025] The first energy storage device is connected to the DC bus of the cutting machine power supply system so that it can output electrical energy to the DC bus when the cutting machine is powered off; the control system of the cutting machine power supply system is connected to the second energy storage device so that it can output electrical energy to the control system when the cutting machine is powered off.

[0026] In one implementation, when a power outage of the cutting machine is detected, acquiring the target voltage of the DC bus includes:

[0027] When the power outage of the cutting machine is detected, the voltage of the DC bus at the moment of power outage is collected, and the collected result is used as the target voltage of the DC bus.

[0028] In one implementation, it further includes:

[0029] The voltage of the DC bus at the moment of power failure is preprocessed.

[0030] Determine whether the voltage value after preprocessing is within the preset second value range;

[0031] If so, the preprocessed voltage value will be used as the target voltage of the obtained DC bus.

[0032] If not, the target voltage of the DC bus will be configured to a preset fixed value.

[0033] Secondly, the present invention also provides a power-off control device for a cutting machine, comprising:

[0034] Memory, used to store computer programs;

[0035] A processor for executing the computer program to implement the steps of the cutting machine power-off control method as described above.

[0036] Thirdly, the present invention also provides a computer program product, including a computer program / instruction that, when executed by a processor, implements the steps of the cutting machine power-off control method as described above.

[0037] Applying the technical solution provided in the embodiments of this invention, considering that power outages or abnormal machine power outages are difficult to completely avoid, this application provides a solution that can smoothly stop the cutting machine during a power outage to prevent wire breakage in order to effectively reduce losses. Specifically, the cutting machine power supply system needs to be equipped with an emergency power supply so that temporary power can be provided when the cutting machine loses power.

[0038] In terms of control strategy, a virtual spindle needs to be set up so that its speed serves as the master speed during the cutting machine's operation. For any motor participating in the wire mesh motion control, the target speed of the motor needs to be determined based on the master speed and the motor's speed-following ratio, and the motor's speed control is then performed based on this target speed. In other words, each motor participating in the wire mesh motion control uses the virtual spindle's speed as a reference for its own speed. Therefore, controlling the master speed is equivalent to effectively controlling the speeds of all motors participating in the wire mesh motion control, ensuring coordinated operation of the relevant motor axes. When a power outage is detected in the cutting machine, the target voltage of the DC bus is acquired, and the speed of the virtual spindle is reduced to a preset threshold, enabling the cutting machine to achieve a controllable shutdown. The preset threshold can be set to 0, i.e., the master speed is reduced to 0. Since the speed of each motor participating in the wire mesh motion control follows the master speed according to its corresponding speed-following ratio, the speeds of these motors will gradually decrease to 0, thus stopping the cutting machine. Furthermore, this application considers that as the main speed decreases to a preset threshold, ensuring the stability of the actual voltage of the DC bus guarantees the effective power supply to the motors involved in the wire network motion control. Ensuring the effective power supply to these motors ensures their speed follows the main speed well, gradually decreasing until the cutting machine stops, guaranteeing the coordinated operation of the relevant motor shafts and thus preventing wire breakage. The DC bus voltage is affected by the magnitude of the main speed deceleration. Therefore, this application uses the target voltage of the DC bus as the feedback control objective during the main speed reduction to the preset threshold, adjusting the magnitude of the main speed deceleration to effectively ensure the stability of the actual voltage of the DC bus.

[0039] In summary, the proposed solution can effectively ensure the stability of the actual voltage of the DC bus by adjusting the deceleration of the main speed, thereby ensuring the effective power supply of the motors involved in the wire mesh motion control. The speed of these motors follows the main speed well, realizing the coordinated work of the relevant motor shafts. Therefore, the wire mesh can be prevented from breaking when the cutting machine is powered off. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art 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.

[0041] Figure 1 The flowchart illustrates the implementation of a power-off control method for a cutting machine according to a specific embodiment of the present invention.

[0042] Figure 2 This is a schematic diagram of the power supply system for a cutting machine in a specific embodiment of the present invention;

[0043] Figure 3 This is a schematic diagram illustrating the power-off control of a cutting machine in an actual production setting according to a specific embodiment of the present invention.

[0044] Figure 4 This is a schematic diagram of the structure of a cutting machine power-off control device provided in a specific embodiment of the present invention;

[0045] Figure 5 This is a schematic diagram of the structure of a computer-readable storage medium according to the present invention. Detailed Implementation

[0046] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this application.

[0047] To enable those skilled in the art to better understand the present invention, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. 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.

[0048] Please refer to Figure 1 , Figure 1 This is a flowchart illustrating an embodiment of a power-off control method for a cutting machine according to a specific embodiment of the present invention. The power-off control method for a cutting machine may include the following steps:

[0049] Step S101: During the operation of the cutting machine, configure the speed of the virtual spindle as the main speed.

[0050] Specifically, the type of cutting machine in this application can be set as needed. For example, it can be a widely used multi-wire cutting machine. The steel wire (usually coated with diamond abrasive grains) of the multi-wire cutting machine is released from the feed wheel, passes through the guide wheel system, and is neatly wound dozens to hundreds of times on multiple main rollers in the cutting zone to form a dense wire mesh plane. Then, it passes through another set of guide wheels and is finally wound onto the take-up wheel. The core principle of the multi-wire cutting machine is to perform grinding-like cutting on the workpiece (such as silicon rods, sapphire, magnetic materials, marble, etc.) through the high-speed reciprocating motion of the wire mesh.

[0051] To prevent wire breakage due to power outages in the cutting machine, the cutting machine power supply system in this application includes an emergency power supply to provide power during power outages. This emergency power supply allows for temporary power supply during a power failure. The specific implementation of the emergency power supply can be set according to actual needs. Considering the need to ensure DC bus voltage stability during shutdown after a power outage, the emergency power supply must typically be able to output power to the DC bus. Furthermore, it must also be able to control the shutdown process after a power outage according to the control strategy of this application, thus requiring it to also output power to the control system of the cutting machine power supply system.

[0052] For example, in one specific embodiment of the present invention, the emergency power supply of the cutting machine power supply system includes a first energy storage device and a second energy storage device. The first energy storage device is connected to the DC bus of the cutting machine power supply system to output electrical energy to the DC bus when the cutting machine is powered off. Furthermore, the control system of the cutting machine power supply system is connected to the second energy storage device to output electrical energy to the control system when the cutting machine is powered off.

[0053] Referring to section 2, the cutting machine power supply system of this application uses a rectifier unit to receive 380V AC power from the power grid and, after rectification, supplies it to the DC bus, so that each motor can receive electrical energy output from the DC bus through its corresponding driver. The rectifier unit can be controlled by the control system of the cutting machine power supply system. Furthermore... Figure 2 In the example, the first energy storage device connected in parallel to the DC bus is specifically a capacitor, which can serve as a backup energy source when the cutting machine is powered off, and output electrical energy to the DC bus.

[0054] In addition to the equipment connected to the DC bus requiring power, the control system of the cutting machine's power supply system also needs to be powered after a power outage to ensure the execution of the solution in this application. The control system of the cutting machine's power supply system typically includes an acquisition unit and a processing unit, which can be implemented by one or two PLCs (Programmable Logic Controllers). Of course, in other specific embodiments, the control system can be implemented by other types of controllers without affecting the implementation of this invention. Figure 2 In this example, a single PLC is used as the control system for the cutting machine's power supply system. When the cutting machine is powered on, the control system's power supply can draw power from the power grid. After the cutting machine loses power, a second energy storage device acts as a backup energy source, supplying power to the control system. The specific type of the second energy storage device can be configured according to actual needs. Figure 2In the example, the second energy storage device is specifically a UPS (Uninterruptible Power Supply), which can usually be implemented by one or more batteries.

[0055] It should also be noted that the power outage of the cutting machine described in this application refers to a power outage caused by abnormal reasons, which typically include power grid outages and abnormal machine power outages. A power grid outage means that the cutting machine cannot receive power from the grid due to reasons such as input network failures. An abnormal machine power outage refers to a power outage caused by reasons such as poor plug contact, accidental disconnection, or accidental switch activation by the operator. When the cutting machine experiences a power outage, if no action is taken, each motor will stop freely, some stopping quickly and others slowly. Therefore, under such uncontrollable conditions, it is easy to cause a power grid outage. The solution in this application, through the design of the aforementioned circuit structure and the control strategy of this application, can ensure that each motor receives power and can stop in a controllable manner after a power outage, thereby ensuring the coordination of each motor and preventing wire breakage. In addition, if the cutting machine stops normally, there will be no power outage during the stopping process, and each motor can achieve a controllable stop.

[0056] In this application, a virtual spindle needs to be established, and the speed of the virtual spindle is called the main speed. Whether the cutting machine is running normally or shutting down after a power outage, the main speed is provided by the virtual spindle, so that the speed of the corresponding motor can change accordingly with the main speed.

[0057] During the operation of the cutting machine, the speed of the virtual spindle can be configured according to actual needs. For example, during normal startup, the speed of the virtual spindle can start from 0 and gradually increase to the required operating speed. Of course, during subsequent normal operation, the speed of the virtual spindle, i.e., the operating speed, can also be adjusted as needed. When the machine is stopped normally, the speed of the virtual spindle can gradually decrease from the operating speed to 0.

[0058] Step S102: For any motor participating in the wire mesh motion control, determine the target speed of the motor based on the main speed and the motor speed follower ratio, and perform motor speed control based on the target speed of the motor.

[0059] It should be noted that for motors not involved in wire mesh motion control, their speed can either follow the virtual spindle speed proportionally or not, employing other control methods without affecting the implementation of this application. This is because, when the cutting machine is powered off, even without control, the electrical components connected to the motor will not affect the wire mesh. For example, Figure 2The left and right tension motors in the middle are used to provide tension to the wire mesh and do not require speed. Therefore, neither of these motors needs to follow the main speed. Figure 2 The feed axis motor is used to connect the feed axis, but the feed axis does not participate in the wire mesh motion control. That is, the feed axis motor is a motor that does not participate in the wire mesh motion control. Therefore, its speed can be selected to follow the main speed or other control methods can be used, which will not affect the implementation of the solution in this application.

[0060] For motors involved in wire mesh motion control, their connected shafts also participate in the wire mesh motion control; therefore, their speed needs to follow the main speed proportionally. Still using... Figure 2 For example, the main speed provided by the virtual spindle is denoted as V. Spindle motor 1, spindle motor 2, spindle motor 3, spindle motor 4, left winding motor, right winding motor, left rigging motor, and right rigging motor are all motors participating in the wire mesh motion control. Their respective target speeds can be expressed as k1×V, k2×V, k3×V, k4×V, k5×V, k6×V, k7×V, and k8×V. Here, k1 to k8 are the speed following ratios of these motors, and the values ​​of k1 to k8 can be determined in advance according to the process.

[0061] It can be seen that when the main speed is determined, the target speed of the motors involved in the wire mesh motion control can be determined. In the following steps, when the main speed gradually decreases to 0, it means that the target speed of these motors will also gradually decrease to 0.

[0062] Motor speed control based on the target speed refers to using the target speed of the motor as the speed command, and then using feedback control or other methods to make the actual speed of the motor reach the target speed. In other words, the target speed of the motor is the control objective, and the feedback control method used is usually closed-loop feedback control. Therefore, it can be understood that when the target speed of the motor gradually decreases to 0, the actual speed of the motor will also gradually decrease to 0. Thus, in the example above, when the cutting machine starts normally, the speed of the virtual spindle gradually increases from 0 to the required operating speed, and the motors following the virtual spindle will also follow proportionally to the corresponding speed. Similarly, when the machine stops normally, the speed of the virtual spindle gradually decreases from the operating speed to 0, and the motors following the virtual spindle will also follow proportionally to the corresponding speed.

[0063] When controlling the motor speed based on the target speed, it can usually be controlled by the control system of the cutting machine's power supply system, for example... Figure 2 In this example, the PLC can control the drivers of each motor, thereby achieving control of the corresponding motor. Of course... Figure 2For ease of viewing, the connection relationship between each driver and the PLC is not shown.

[0064] Step S103: When the power outage of the cutting machine is detected, the target voltage of the DC bus is obtained.

[0065] During the operation of the cutting machine, power outage signals are monitored, usually in real time, to detect power outages early. When a power outage signal is detected, it can be determined that the cutting machine is powered off. At this point, it is necessary to obtain the target voltage of the DC bus. This voltage is the control target for the DC bus voltage in the subsequent process. That is, it is necessary to ensure that the actual voltage of the DC bus can be stabilized near the target voltage of the DC bus when the main speed is reduced to 0. As described above, during this process, the first energy storage device will output electrical energy to the DC bus as a temporary power source.

[0066] There are several ways to obtain the target voltage of the DC bus. For example, a simple way is to store the voltage of the DC bus during normal operation, and then when the power of the cutting machine is detected to be off, this pre-stored fixed value can be obtained as the target voltage of the DC bus.

[0067] In one specific embodiment of the present invention, when a power outage of the cutting machine is detected, obtaining the target voltage of the DC bus may specifically include:

[0068] When the power outage of the cutting machine is detected, the voltage of the DC bus at the moment of power outage is collected, and the collected result is used as the target voltage of the DC bus.

[0069] This implementation takes into account that if a predetermined fixed value is used as the target voltage of the DC bus required by the present application, the operator needs to preset the fixed value. In different situations, due to different cutting machine models, differences in grid voltage, etc., the voltage of the DC bus in the stable state during normal operation is also different, and the voltage of the DC bus also fluctuates. This requires the operator to preset the fixed value based on experience and the voltage fluctuation curve of the DC bus in the actual situation. This requires a high level of experience from the operator, and the preset fixed value may not be reasonable.

[0070] In this embodiment, when a power outage is detected in the cutting machine, the voltage of the DC bus at the moment of power failure is collected. The collection method can be selected according to actual needs. Since the power outage has just occurred, the DC bus voltage collected at this time is more consistent with the stable voltage of the DC bus under the current conditions. Therefore, the collected result can be used as the target voltage of the DC bus, ensuring the reliability of the target voltage of the DC bus obtained by the present application.

[0071] Furthermore, in one specific embodiment of the present invention, it may also include:

[0072] The voltage of the DC bus at the moment of power failure is preprocessed.

[0073] Determine whether the voltage value after preprocessing is within the preset second value range;

[0074] If so, the preprocessed voltage value will be used as the target voltage of the obtained DC bus.

[0075] If not, the target voltage of the DC bus will be configured to a preset fixed value.

[0076] This implementation takes into account that the DC bus voltage collected at the moment of power failure is usually consistent with the stable DC bus voltage under the current conditions. However, the operating environment of the cutting machine is relatively complex. In some cases, due to interference, power grid voltage fluctuations, and other factors, the collected DC bus voltage at the moment of power failure may deviate significantly from the stable DC bus voltage under the current conditions. Therefore, the collected DC bus voltage at the moment of power failure is preprocessed to reduce errors. Of course, the specific preprocessing method can be set according to actual needs, and may include various filtering methods.

[0077] Furthermore, in this implementation, the pre-processed voltage value is further determined to be within a preset second numerical range. If it is not, it indicates that even with pre-processing, the obtained value is still somewhat abnormal. Therefore, the target voltage of the DC bus is configured to a preset fixed value, which is usually determined by the operator based on experience. Of course, if the pre-processed voltage value is within the preset second numerical range, it can be considered a reasonable value and thus can be used as the obtained target voltage of the DC bus.

[0078] Step S104: Reduce the main speed to a preset threshold, and during the reduction process, use the actual voltage of the DC bus equal to the target voltage as the target of feedback control to adjust the magnitude of the main speed deceleration.

[0079] Upon detecting a power outage in the cutting machine and obtaining the target voltage of the DC bus, the main speed can be reduced to a preset threshold to stop the cutting machine. The specific value of the preset threshold can be set according to actual needs. It can usually be set to 0. Of course, in other cases, it can be set to a small value slightly greater than 0. As long as the main speed is reduced to the preset threshold and the speed of the relevant motor changes with the main speed, the cutting machine can be stopped. In other words, the preset threshold value is set so that the cutting machine can stop when the main speed is reduced to the preset threshold.

[0080] Furthermore, the deceleration rate is continuously adjusted during the reduction process. This operation controls the rate of energy feedback during deceleration, ensuring that the actual voltage of the DC bus remains near the target voltage, which is also near the DC bus voltage during normal operation before the power outage. This guarantees that the entire machine system will not lose power during shutdown and prevents the network from breaking down.

[0081] There are several ways to adjust the magnitude of the main speed deceleration. As long as the magnitude of the main speed deceleration can be controlled to stabilize the actual voltage of the DC bus near the target voltage, it is acceptable.

[0082] In one specific embodiment of the present invention, the main speed is reduced to a preset threshold, and during the reduction process, the actual voltage of the DC bus is equal to the target voltage as the target of feedback control, and the magnitude of the main speed deceleration is adjusted, which may include:

[0083] The main speed is reduced to a preset threshold. During the reduction process, when the actual voltage of the DC bus is greater than the target voltage, the deceleration of the main speed is reduced, and when the actual voltage of the DC bus is less than the target voltage, the deceleration of the main speed is increased.

[0084] This implementation takes into account that after the cutting machine is powered off, during the process of the main speed decreasing to a preset threshold, increasing the deceleration of the main speed will increase the energy feedback speed of each motor, leading to an increase in the DC bus voltage. Conversely, decreasing the deceleration of the main speed will decrease the energy feedback speed of each motor, leading to a decrease in the DC bus voltage. To ensure the reliability of the shutdown process, the actual voltage of the DC bus needs to be stabilized near the target voltage. Therefore, in this implementation, when the actual voltage of the DC bus is detected to be greater than the target voltage, the deceleration of the main speed can be appropriately reduced, for example, by decreasing the deceleration of the main speed by a preset value. Conversely, when the actual voltage of the DC bus is detected to be less than the target voltage, the deceleration of the main speed can be appropriately increased, for example, by increasing the deceleration of the main speed by a preset value.

[0085] Furthermore, in one specific embodiment of the present invention, the main speed is reduced to a preset threshold, and during the reduction process, when the actual voltage of the DC bus is greater than the target voltage, the deceleration of the main speed is reduced, and when the actual voltage of the DC bus is less than the target voltage, the deceleration of the main speed is increased. This may include:

[0086] The main speed is reduced to a preset threshold, and during the reduction process, the difference between the target voltage and the actual voltage of the DC bus is used as the current voltage error value.

[0087] Based on the voltage error value and the closed-loop feedback algorithm, the current change in deceleration is obtained;

[0088] The default value of the deceleration is added to the current change value of the deceleration to obtain the current deceleration magnitude of the main velocity.

[0089] In this implementation, the magnitude of the main velocity deceleration is adjusted through a closed-loop feedback algorithm. Specifically, the difference between the target voltage and the actual DC bus voltage is used as the current voltage error value, which can be expressed as e(t) = U0 - U(t), where U0 refers to the target DC bus voltage, U(t) refers to the current actual DC bus voltage, and e(t) refers to the current voltage error value. After obtaining the voltage error value, the current change in deceleration can be obtained using a closed-loop feedback algorithm. The closed-loop feedback algorithm used can be selected according to actual needs; for example, it can be a commonly used PID closed-loop feedback algorithm, which can be expressed as: The V here a K represents the current change in the obtained deceleration. p T i T d The coefficients listed in order are the proportional coefficient, integral coefficient, and derivative coefficient of the PID closed-loop feedback algorithm. The values ​​of these coefficients can be set and adjusted by staff according to the actual situation.

[0090] Furthermore, it is understood that, in addition to the PID closed-loop feedback algorithm, the PI closed-loop feedback algorithm, PD closed-loop feedback algorithm, etc., can also be selected according to actual needs. That is, any one or two of the proportional term, integral term, and derivative term of the PID closed-loop feedback algorithm can be selected as the required closed-loop feedback algorithm, which does not affect the implementation of the present invention.

[0091] The current change in deceleration V was obtained. a Then, it is added to the default value of deceleration V0, and expressed as V0+V a This allows us to obtain the current deceleration magnitude of the main speed. It can be seen that, under ideal conditions, the voltage error value e(t) is always 0, that is, the actual voltage of the DC bus is always equal to the target voltage. Therefore, the main speed can be reduced by a fixed amount (in this example, the default value V0) until it is reduced to a preset threshold. As described above, the preset threshold is usually set to 0, that is, the main speed will gradually decrease to 0.

[0092] In one specific embodiment of the present invention, it may further include:

[0093] Determine whether the current voltage error value does not exceed the preset first value range;

[0094] If so, replace the current voltage error value with 0.

[0095] This implementation further considers that if the current voltage error value e(t) is small, it can be directly regarded as 0. This helps reduce the impact of noise interference, avoids system oscillation, allows the bus voltage to converge to the target value more smoothly, improves stability, simplifies control logic, and reduces computational burden. Therefore, after obtaining the current voltage error value, this implementation determines whether the current voltage error value does not exceed a preset first numerical range. If it does not exceed the preset first numerical range, the current voltage error value can be replaced with 0, that is, the current voltage error value e(t) is directly regarded as 0. Of course, if it exceeds the preset first numerical range, there is no need to replace the current voltage error value with 0.

[0096] In one specific embodiment of the present invention, it may further include:

[0097] Obtain the numerical adjustment range of the deceleration;

[0098] Adjusting the magnitude of the deceleration of the main velocity includes:

[0099] Adjust the magnitude of the main speed deceleration according to the rule that the deceleration of the main speed does not exceed the numerical adjustment range.

[0100] This implementation takes into account that if the main speed deceleration is too large, the target speed of some motors may be too high, exceeding the operating speed range of the motors. Conversely, if the main speed deceleration is too small, the required deceleration time may be too long, making it difficult for the first energy storage device to support power supply for such a long time. Therefore, this implementation obtains a pre-set numerical adjustment range for the deceleration. During the adjustment of the main speed deceleration, the deceleration must be adjusted according to the rule that the deceleration does not exceed this numerical adjustment range. In other words, the numerical adjustment range of the deceleration is used as a constraint condition for adjusting the deceleration of the main speed. This effectively avoids adverse situations caused by excessive or insufficient deceleration of the main speed, further ensuring the reliability of the solution in this application.

[0101] Appendix Figure 3 This diagram illustrates a specific implementation of power-off control for a cutting machine in an actual production setting. From top to bottom, it shows the main speed curve, the main speed deceleration curve, the PI output curve of the PI closed-loop feedback algorithm used to adjust the main speed deceleration after power failure, the DC bus voltage curve, and the target DC bus voltage. It can be seen that after power failure, the main speed decreases at a certain rate until it reaches zero. The magnitude of the deceleration is continuously adjusted to stabilize the DC bus voltage near the target voltage.

[0102] Applying the technical solution provided in this invention, considering that power outages or abnormal machine power outages are difficult to completely avoid, this application provides a solution to smoothly stop the cutting machine during a power outage and prevent wire breakage in order to effectively reduce losses. Specifically, the cutting machine power supply system needs to be equipped with an emergency power supply so that temporary power can be provided when the cutting machine loses power. For example, a first energy storage device can be connected to the DC bus so that when the cutting machine loses power, the first energy storage device can output electrical energy to the DC bus, that is, it can provide temporary power to ensure that the cutting machine can stop smoothly. Furthermore, the control system of the cutting machine power supply system also needs emergency power supply. Therefore, the control system is connected to a second energy storage device so that it can output electrical energy to the control system when the cutting machine loses power, so that the control system can still perform its control functions when the cutting machine loses power.

[0103] In terms of control strategy, a virtual spindle needs to be set up so that its speed serves as the master speed during the cutting machine's operation. For any motor participating in the wire mesh motion control, the target speed of the motor needs to be determined based on the master speed and the motor's speed-following ratio, and the motor's speed control is then performed based on this target speed. In other words, each motor participating in the wire mesh motion control uses the virtual spindle's speed as a reference for its own speed. Therefore, controlling the master speed is equivalent to effectively controlling the speeds of all motors participating in the wire mesh motion control, ensuring coordinated operation of the relevant motor axes. When a power outage is detected in the cutting machine, the target voltage of the DC bus is acquired, and the speed of the virtual spindle is reduced to a preset threshold, enabling the cutting machine to achieve a controllable shutdown. The preset threshold can be set to 0, that is, the master speed is reduced to 0. Since the speed of each motor participating in the wire mesh motion control follows the master speed according to its corresponding speed-following ratio, the speeds of these motors will gradually decrease to 0. Furthermore, this application considers that as the main speed decreases to a preset threshold, ensuring the stability of the actual voltage of the DC bus guarantees the effective power supply to the motors involved in the wire mesh motion control. Ensuring the effective power supply to these motors ensures their speed follows the main speed closely, gradually decreasing to 0, causing the cutting machine to stop and guaranteeing the coordinated operation of the relevant motor shafts, thus preventing wire breakage. The DC bus voltage is affected by the magnitude of the main speed deceleration. Therefore, this application uses the target voltage of the DC bus as the feedback control objective during the main speed reduction to the preset threshold, adjusting the magnitude of the main speed deceleration to effectively ensure the stability of the actual voltage of the DC bus.

[0104] In summary, the proposed solution can effectively ensure the stability of the actual voltage of the DC bus by adjusting the deceleration of the main speed, thereby ensuring the effective power supply of the motors involved in the wire mesh motion control. The speed of these motors follows the main speed well, realizing the coordinated work of the relevant motor shafts. Therefore, the wire mesh can be prevented from breaking when the cutting machine is powered off.

[0105] Corresponding to the above method embodiments, the present invention also provides a cutting machine power-off control device, a computer-readable storage medium, and a computer program product, which can be referred to in conjunction with the above.

[0106] See Figure 4 As shown, the device may include:

[0107] Memory 401 is used to store computer programs;

[0108] Processor 402 is configured to execute a computer program to implement the steps of the cutting machine power-off control method as described in any of the above embodiments.

[0109] The computer program product includes a computer program / instruction that, when executed by a processor, implements the steps of the cutting machine power-off control method as described in any of the above embodiments.

[0110] See also Figure 5 The computer-readable storage medium 50 stores a computer program 51, which, when executed by a processor, implements the steps of the cutting machine power-off control method as described in any of the above embodiments. The computer-readable storage medium 50 referred to herein includes RAM (Random Access Memory), main memory, ROM (Read-Only Memory), EEPROM (Electrically Erasable Programmable Read Only Memory), registers, hard disks, removable disks, or any other form of storage medium known in the art.

[0111] It should also be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0112] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0113] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the technical solutions and core ideas of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the present invention.

Claims

1. A cutting machine power-off control method, characterized by, The cutting machine power supply system has an emergency power supply for supplying power when the cutting machine is powered off, and the cutting machine power-off control method comprises: During the operation of the cutting machine, the speed of the virtual main shaft is configured as the main speed; For any motor participating in line network motion control, the target speed of the motor is determined based on the main speed and the speed following proportion of the motor, and the speed control of the motor is performed based on the target speed of the motor; When detecting that the cutting machine is powered off, the target voltage of the DC bus is obtained; The main speed is reduced to a preset threshold, and during the reduction, the actual voltage of the DC bus is equal to the target voltage as the target of feedback control, and the deceleration size of the main speed is adjusted.

2. The power-off control method of a cutting machine according to claim 1, characterized in that, The main speed is reduced to a preset threshold, and during the reduction, the actual voltage of the DC bus is equal to the target voltage as the target of feedback control, and the deceleration size of the main speed is adjusted, comprising: The main speed is reduced to a preset threshold, and during the reduction, when the actual voltage of the DC bus is greater than the target voltage, the deceleration of the main speed is reduced, and when the actual voltage of the DC bus is less than the target voltage, the deceleration of the main speed is increased.

3. The power-off control method of a cutting machine according to claim 2, characterized in that, The main speed is reduced to a preset threshold, and during the reduction, when the actual voltage of the DC bus is greater than the target voltage, the deceleration of the main speed is reduced, and when the actual voltage of the DC bus is less than the target voltage, the deceleration of the main speed is increased, comprising: The main speed is reduced to a preset threshold, and during the reduction, the difference obtained by subtracting the actual voltage of the DC bus from the target voltage is taken as the current voltage error value; Based on the voltage error value and a closed-loop feedback algorithm, a current change value of the deceleration is obtained; The default value of the deceleration is superimposed with the current change value of the deceleration to obtain the current deceleration size of the main speed.

4. The power-off control method of a cutting machine according to claim 3, wherein Further comprising: determining whether the current voltage error value exceeds a preset first numerical range; If yes, the current voltage error value is replaced with 0.

5. The power-off control method of a cutting machine according to claim 1, wherein Further comprising: obtaining a numerical adjustment range of the deceleration; adjusting the deceleration size of the main speed, comprising: adjusting the deceleration size of the main speed according to the rule that the deceleration of the main speed does not exceed the numerical adjustment range.

6. The power-off control method of a cutting machine according to claim 1, wherein The emergency power supply of the cutting machine power supply system comprises a first energy storage device and a second energy storage device; The first energy storage device is connected to the DC bus of the cutting machine power supply system to output electric energy to the DC bus through the first energy storage device when the cutting machine is powered off; and the control system of the cutting machine power supply system is connected to the second energy storage device to output electric energy to the control system when the cutting machine is powered off.

7. The power-off control method of a cutting machine according to any one of claims 1 to 6, characterized in that, When detecting that the cutting machine is powered off, the target voltage of the DC bus is obtained, comprising: When detecting that the cutting machine is powered off, the voltage of the DC bus at the power-off time is collected, and the collection result is taken as the obtained target voltage of the DC bus.

8. The power-off control method of a cutting machine according to claim 7, wherein, Further comprising: preprocessing the collected voltage of the DC bus at the power-off time; determining whether the voltage value after preprocessing is within a preset second numerical range; If yes, the voltage value after the preprocessing is taken as the target voltage of the acquired DC bus; If no, the target voltage of the DC bus is configured as a preset fixed value.

9. A cutting machine power-off control apparatus, characterized by, The method comprises the steps of: a memory for storing a computer program; a processor for executing the computer program to implement the steps of the cutting machine power-off control method according to any one of claims 1 to 8.

10. A computer program product comprising computer programs / instructions, characterized in that, The computer program / instruction is executed by the processor to implement the steps of the cutting machine power-off control method according to any one of claims 1 to 8.

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