A remote control system for frequency converter

Abstract

The present invention discloses a frequency converter remote control system, which relates to the technical field of tower crane operation control. The system collects key data of the boom or hook in real time through the inertial swing monitoring points set by the area division module, and combines the frequency converter acceleration and deceleration parameters with the load weight change to construct and evaluate the inertial swing risk index IB, and generate a first control strategy to reduce the swing risk. The second alarm module further combines the multi-dimensional data analysis of wind speed and dynamic load changes to optimize the first control strategy, generate the second control strategy, and improve the response capability to emergencies. The compensation evaluation module dynamically evaluates the compensation accuracy and optimizes the control strategy by monitoring the torque and slip state of the frequency converter, thereby reducing errors and improving system accuracy. In general, the present invention not only improves the safety and stability during the lifting process, but also significantly reduces the operational risks caused by external factors such as load fluctuations and wind speed changes.

Description

Technical Field

[0001] The invention relates to the technical field of tower crane operation control, in particular to a frequency converter remote control system. Background Art

[0002] As an indispensable heavy machinery in large-scale engineering construction, the operation stability and safety of tower cranes are of great significance to the progress of the project and the safety of the working environment. As a core equipment, the operation efficiency and safety of tower cranes directly affect the progress and quality of the overall project. The inverter directly controls the speed and output power of the motor. The mechanical actions of the tower crane (such as boom lifting, hook swinging, etc.) are driven by the motor drive, so the inverter adjusts the speed and power output of the motor, which will directly affect the stability of these mechanical actions. As a driving device, the motor controls the main mechanical components of the tower crane. For example, the motor drives the lifting arm, hook, turret and other components of the tower crane through its output torque. When the inverter adjusts the speed and power of the motor, the movement speed of the boom, the stability of lifting, the load capacity of the hook, etc. will be affected. However, in actual applications, due to the complexity of the operation of tower cranes and the variability of the environment, they have the following main problems:

[0003] 1. Risk of inertial swing:

[0004] The boom and hook of a tower crane are easily affected by inertia, gravity, and acceleration and deceleration during lifting and transportation, resulting in obvious swing. This swing not only reduces the accuracy of lifting, but also poses a safety threat to the surrounding environment and personnel. Traditional technologies usually use manual observation or simple fixed value control methods, which cannot evaluate and adjust the swing risk in real time, resulting in a high risk of accidents.

[0005] 2. Inadequate handling of dynamic load fluctuations:

[0006] In actual operation, the load of the hook and boom fluctuates frequently due to the dynamic influence of wind speed, load weight changes and lifting actions. Traditional monitoring systems mostly make judgments based on a single parameter and cannot conduct a comprehensive analysis of the multi-dimensional changes of the boom, hook and load, resulting in untimely warning of load fluctuation risks and insufficient adjustment strategies.

[0007] 3. The inverter compensation adjustment accuracy is low:

[0008] In the inverter control of tower cranes, asynchronous motor slip compensation and torque compensation are the key to ensure the smooth operation of the equipment. However, traditional inverter compensation systems usually rely on fixed thresholds or simple proportional control, and cannot accurately correct the deviation of slip frequency and output torque in real time. This will not only cause vibration and instability during the hoisting process, but may also cause additional losses to the motor itself and shorten the life of the equipment. Summary of the invention

[0009] In view of the deficiencies in the prior art, the present invention provides a frequency converter remote control system to solve the problems mentioned in the background technology.

[0010] To achieve the above objectives, the present invention is implemented through the following technical solutions: A frequency converter remote control system includes a region division module, a first alarm module, a second alarm module and a compensation evaluation module;

[0011] An area division module is used to divide the key monitoring area during the operation of the tower crane into multiple sub-areas, and set an inertial swing monitoring point and a dynamic load monitoring point in each sub-area;

[0012] The first alarm module is used to collect the swing amplitude, swing period and swing angle of the boom or hook in real time according to the inertial swing monitoring point, and collect the acceleration power of the inverter and deceleration power And collect the real-time load weight of tower cranes , to construct an inertial swing risk index IB; preset an inertial swing threshold value X, when the inertial swing risk index IB exceeds the inertial swing threshold value X, trigger a first alarm and generate a first control strategy through a remote control module to reduce the swing risk;

[0013] The second alarm module, after the first alarm is triggered and optimized, collects wind speed data and dynamic load changes in the actual operating environment of the tower crane in real time, and constructs a dynamic load change rate ;Preset dynamic load change threshold , when the dynamic load change rate Exceeding the dynamic load change threshold When a second alarm is triggered, the remote control module generates a second control strategy for making corrections on the first control strategy;

[0014] The compensation evaluation module is used to monitor the slip compensation and torque compensation status of the inverter in real time during operation and collect the real-time output torque of the motor. and slip frequency , construct the torque compensation error index Slip compensation error index and evaluate.

[0015] The remote control module is used to generate corresponding control strategies according to the first alarm, the second alarm, the third alarm and the fourth alarm, and remotely adjust the operating state of the inverter, including power regulation, torque correction and slip frequency adjustment.

[0016] Preferably, the area division module includes a boom monitoring unit, a hook monitoring unit and a load monitoring unit;

[0017] The boom monitoring unit is used to set the first inertial swing monitoring point at a certain interval of the boom length, including 5-10 meters, and collect the real-time data of the boom in real time through an acceleration sensor or a gyroscope, including:

[0018] Boom swing range : Maximum offset distance of boom swing;

[0019] Boom swing cycle : A complete cycle time of boom swing;

[0020] Boom swing angle : Change of the horizontal angle of the boom swing;

[0021] The hook monitoring unit is responsible for setting the second inertial swing monitoring point at the hook position, and collecting real-time hook data through an acceleration sensor or gyroscope, including:

[0022] Hook swing range : Maximum offset distance of hook swing;

[0023] Hook swing cycle : A complete cycle time of hook swing;

[0024] Hook swing angle : Change of hook swing space angle;

[0025] The load monitoring unit is used to set dynamic load monitoring points on the hook to install weight sensors to collect and obtain real-time load weight. .

[0026] Preferably, the first alarm module includes an extraction unit, a frequency converter acquisition unit and a first calculation unit;

[0027] The extraction unit is used to extract the boom swing amplitude from the real-time data of the boom. , boom swing cycle and boom swing angle ; and extract the hook swing amplitude in the real-time hook data , hook swing cycle and hook swing angle And the real-time load weight obtained from the dynamic load monitoring point After: data cleaning, missing value processing and dimensionless processing;

[0028] The inverter acquisition unit is used to collect the acceleration power of the inverter and deceleration power .

[0029] Preferably, the first calculation unit is used to construct an inertial swing risk index IB based on the data collected and processed by the extraction unit and the frequency converter collection unit;

[0030] The specific steps of constructing the Inertia Swing Risk Index IB include:

[0031] S11. Extract the swing amplitude of the boom , boom swing cycle and boom swing angle , the boom inertia swing index is calculated by the following formula :

[0032] ;

[0033] In the formula, Indicates the boom length, Indicates the boom swing angle When the boom swing angle is small (close to horizontal), The value of is close to 1; when the angle is large (close to vertical), The value of is close to 0;

[0034] S12, extract the swing amplitude of the hook , hook swing cycle and hook swing angle , the hook inertia swing index is calculated by the following formula :

[0035] ;

[0036] In the formula, It represents the risk weight coefficient of hook swing, which is determined by load test data or simulation results; Indicates the hook swing angle The sine value of the swing angle is close to 1 when the swing angle is large, indicating that the swing has a greater impact; when the swing angle is small, the sine value is close to 0;

[0037] S13, combined with acceleration power , deceleration power and real-time load weight , the inertial swing risk index IB is calculated by the following formula:

[0038] ;

[0039] In the formula, and represent weight coefficients, and , , .

[0040] Preferably, the first alarm module further includes a first judgment unit, which is used to preset an inertial swing threshold value X and compare the inertial swing risk index IB with the inertial swing threshold value X to determine whether there is an inertial swing risk, including:

[0041] If the inertial swing risk index IB ≤ the inertial swing threshold value X, it means that the tower crane has no inertial swing risk and operates normally without adjustment;

[0042] If the inertial swing risk index IB> inertial swing threshold X, it means that the tower crane has an inertial swing risk and operates abnormally, triggering the first alarm and generating the first control strategy through the remote control module, including: adjusting and reducing the current acceleration power by 3%-5% And reduce the current deceleration power 3%-5% of the value of the first adjustment parameter is generated.

[0043] Preferably, the second alarm module includes an environment collection unit, a second analysis unit and a second judgment unit;

[0044] The environment acquisition unit is used to collect wind speed data of the actual working environment of the tower crane in real time after the first control strategy is implemented, obtain the wind speed value Fs, and extract the boom swing angle , hook swing angle and real-time load weight After dimensionless processing, the second analysis unit calculates the dynamic load change rate using the following formula: :

[0045] ;

[0046] ;

[0047] ;

[0048] In the formula, Indicates the change in the boom swing angle. Indicates the boom swing angle at the end of the monitoring time, Indicates the boom swing angle at the beginning of the monitoring time; Indicates the change in hook swing angle. Indicates the hook swing angle at the end of the monitoring time. Indicates the hook swing angle at the beginning of the monitoring time; use the angle sensor to monitor the swing angle of the boom or hook in real time.

[0049] Preferably, the second judgment unit is used to preset a dynamic load change threshold , to determine whether there is a risk of load fluctuation, including:

[0050] If the dynamic load change rate >Dynamic load change threshold When the load fluctuation risk exists, the second alarm is triggered, and the remote control module generates a second control strategy based on the second alarm, including: further adjusting the current acceleration power to reduce 6%-8% on the first adjustment parameter value. And reduce the current deceleration power 6%-8% of the value of the second adjustment parameter is generated;

[0051] If the dynamic load change rate ≤ Dynamic load change threshold When , it means there is no risk of load fluctuation and continuous monitoring is performed.

[0052] Preferably, the compensation evaluation module includes a third acquisition unit and a third calculation unit;

[0053] The third acquisition unit is used to collect the slip frequency of the asynchronous motor of the inverter in real time during operation. and output torque ;

[0054] Output torque It is the actual rotational torque generated during operation;

[0055] Slip frequency It is the difference between the speed of the asynchronous motor and the synchronous speed during operation;

[0056] The third calculation unit is used to calculate the output torque and slip frequency , calculate the torque compensation error index using the following formula Slip compensation error index :

[0057] ;

[0058] ;

[0059] in, represents the output torque of the i-th sampling, Indicates the theoretical torque threshold calculated according to the inverter control instruction; represents the slip frequency of the i-th sampling, Indicates the theoretical target slip frequency threshold;

[0060] Indicates the maximum difference between the output torque sampled at the i-th time and the theoretical torque threshold;

[0061] Indicates the maximum difference between the slip frequency sampled at the ith time and the theoretical target slip frequency threshold;

[0062] , , and is the weight, , , , ,and , , , n is the total number of samples.

[0063] Preferably, the compensation evaluation module further includes a third judgment unit, which is used to preset a torque abnormality threshold. ; and the torque compensation error index Torque abnormality threshold Compare to determine whether there is any abnormality in the torque, including:

[0064] If the torque compensation error index ≥Torque abnormality threshold , indicating that there is an abnormality in the torque compensation, triggering the third alarm, and the remote control module generates a third control strategy, including: adjusting the motor speed by ±5%-10% to compensate the output torque;

[0065] If the torque compensation error index <Torque abnormality threshold , indicating that there is no abnormality in the torque compensation and monitoring is continued.

[0066] Preferably, the compensation evaluation module further includes a fourth judgment unit, which is used to preset a slip abnormality threshold. , and the slip compensation error index Slippage Abnormal Threshold Compare to determine whether there is any abnormality in slip compensation, including:

[0067] If the slip compensation error index ≥ Slippage Abnormal Threshold , it indicates that there is an abnormality in the slip compensation, triggering the fourth alarm, and the remote control module generates a fourth control strategy, including: reducing the slip frequency by 5%-10% Make corrections to avoid instability caused by over-adjustment;

[0068] If the slip compensation error index <Slippage abnormal threshold , it means that there is no abnormality in slip compensation and monitoring is continued.

[0069] The present invention provides a frequency converter remote control system, which has the following beneficial effects:

[0070] (1) This inverter remote control system can calculate and warn of potential inertial swing risks in real time by accurately monitoring the swing amplitude, cycle, angle and load of the boom and hook, combined with the acceleration and deceleration control information of the inverter. When the system detects that the swing amplitude exceeds the safe range, it can trigger an alarm and adjust the control strategy in time to reduce the risk of unstable operation of the equipment, thereby promoting the overall safety of the tower crane and avoiding accidents caused by improper operation.

[0071] (2) The present invention combines the inverter's acceleration and deceleration control data with load status information, and through multi-level control strategies (such as inertial swing compensation and dynamic load adjustment), can optimize the inverter's operating parameters to ensure that a smooth acceleration and deceleration process can be maintained in a complex working environment. When unstable factors are detected, the system will automatically adjust the inverter's control parameters (such as slowing down the acceleration or deceleration amplitude), reduce equipment vibration and instability, and improve the system's response speed and control accuracy.

[0072] (3) The present invention combines the dynamic changes of wind speed and load in environmental data, and can perform accurate risk assessment in different working scenarios of tower cranes by calculating multi-dimensional indicators such as dynamic load change rate and inertial swing risk index. When the risk index exceeds the preset threshold, the system automatically triggers a two-level alarm mechanism, thereby effectively warning of possible dangerous situations in advance and ensuring that staff can take timely countermeasures to prevent accidents.

[0073] (4) Through real-time monitoring and dynamic adjustment of control strategies, the present invention can significantly improve the operational stability of tower cranes and avoid operational instability caused by load fluctuations, wind speed changes or equipment misoperation. By reducing vibration and unstable operation of equipment, the system can improve the continuity and efficiency of the production process, while reducing the wear and failure rate of mechanical equipment and extending the service life of the equipment, thereby improving the overall production efficiency of tower cranes. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] Figure 1 The present invention is a flowchart diagram of a frequency converter remote control system. DETAILED DESCRIPTION

[0075] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0076] Example 1

[0077] See also Figure 1 , the present invention provides a frequency converter remote control system, comprising a region division module, a first alarm module, a second alarm module and a compensation evaluation module;

[0078] An area division module is used to divide the key monitoring area during the operation of the tower crane into multiple sub-areas, and set an inertial swing monitoring point and a dynamic load monitoring point in each sub-area;

[0079] The first alarm module is used to collect the swing amplitude, swing period and swing angle of the boom or hook in real time according to the inertial swing monitoring point, and collect the acceleration power of the inverter and deceleration power And collect the real-time load weight of tower cranes , to construct an inertial swing risk index IB; preset an inertial swing threshold value X, when the inertial swing risk index IB exceeds the inertial swing threshold value X, trigger a first alarm and generate a first control strategy through a remote control module to reduce the swing risk;

[0080] The second alarm module, after triggering the first alarm and optimizing, collects wind speed data and dynamic load changes of the actual operating environment of the tower crane in real time, and constructs a dynamic load change rate ;Preset dynamic load change threshold , when the dynamic load change rate Exceeding the dynamic load change threshold When a second alarm is triggered, the remote control module generates a second control strategy for making corrections on the first control strategy;

[0081] The compensation evaluation module is used to monitor the slip compensation and torque compensation status of the inverter in real time during operation, and collect the real-time output torque of the motor. and slip frequency , construct the torque compensation error index Slip compensation error index And evaluate, if it is judged that the torque compensation is abnormal, trigger the third alarm; if it is judged that the slip compensation is abnormal, trigger the fourth alarm;

[0082] The remote control module is used to generate corresponding control strategies according to the first alarm, the second alarm, the third alarm and the fourth alarm, and remotely adjust the operating state of the inverter, including power regulation, torque correction and slip frequency adjustment, so as to realize real-time remote control and optimization of the tower crane operation.

[0083] In this embodiment, the inertial swing monitoring points set by the area division module are used to collect key data such as the swing amplitude, period, angle, etc. of the boom or hook in real time. At the same time, the inertial swing risk index IB is accurately constructed by combining the dynamic changes of the inverter acceleration and deceleration parameters and the real-time load weight. Traditional methods mostly rely on manual observation or simple fixed values, which are difficult to adjust dynamically; the present invention makes the assessment of inertial swing more accurate through comprehensive analysis of multiple parameters, ensuring the visualization and quantification of swing risks. When the inertial swing risk index IB exceeds the inertial swing threshold value X, the first alarm is triggered and the first control strategy is generated through the remote control module to reduce the swing risk; and the first control strategy including dynamic deceleration, swing balance and load adjustment is generated to effectively reduce the swing risk during the lifting process. Compared with the traditional simple acceleration and deceleration control, this system can dynamically adjust the boom operation trajectory and inverter operation to improve the safety and stability of the lifting process.

[0084] After the first alarm is triggered, the second alarm module further monitors the wind speed, dynamic load change and other data in the working environment of the tower crane in real time, and constructs the dynamic load change rate through comprehensive analysis of multiple parameters. Compared with the traditional monitoring method based on only a single parameter, the present invention can simultaneously consider multiple factors such as load weight, hoisting action, wind speed change, etc., and more comprehensively reflect the risk of load fluctuation. Exceeding the dynamic load change threshold When the second alarm module triggers an alarm, the remote control module generates a more detailed second control strategy based on the first control strategy, such as dynamic wind speed compensation and load adjustment strategy, to further optimize the operation of the tower crane. This design not only improves the ability to cope with sudden load fluctuations, but also significantly reduces the operation errors caused by uneven load or sudden changes in wind speed.

[0085] The compensation evaluation module monitors the slip compensation and torque compensation status of the inverter in real time, collects the real-time output torque and slip frequency of the motor, and constructs the torque compensation error index. Slip compensation error index Compared with the traditional method that relies on fixed thresholds or simple proportional control, this system can dynamically evaluate the compensation accuracy and generate targeted compensation optimization strategies based on the error index.

[0086] Based on constructing torque compensation error index Slip compensation error index Based on the evaluation results, the system can correct the slip compensation and torque compensation parameters of the inverter in real time, thereby reducing vibration and instability during the lifting process. This optimization not only improves the control accuracy of the inverter, but also effectively reduces the additional loss of the motor, extends the service life of the equipment, and provides more efficient protection for engineering operations.

[0087] Example 2

[0088] This embodiment is explained in Example 1. For details, please refer to Figure 1 ,The area division module includes a boom monitoring unit, a hook monitoring unit and a load monitoring unit;

[0089] The boom monitoring unit is used to set the first inertial swing monitoring point at a certain interval of the boom length, including 5-10 meters, and collect the real-time data of the boom in real time through an acceleration sensor or a gyroscope, including:

[0090] Boom swing range : Maximum offset distance of boom swing;

[0091] Boom swing cycle : A complete cycle time of boom swing;

[0092] Boom swing angle : Change of the horizontal angle of the boom swing;

[0093] The hook monitoring unit is responsible for setting the second inertial swing monitoring point at the hook position, and collecting real-time hook data through an acceleration sensor or gyroscope, including:

[0094] Hook swing range : Maximum offset distance of hook swing;

[0095] Hook swing cycle : A complete cycle time of hook swing;

[0096] Hook swing angle : Change of hook swing space angle;

[0097] The load monitoring unit is used to set dynamic load monitoring points on the hook to install weight sensors to collect and obtain real-time load weight. The design of the dynamic load monitoring point can sensitively capture the instantaneous changes in load weight and provide reliable data for dynamic load fluctuation analysis.

[0098] The above data is collected and obtained through acceleration sensors, gyroscopes or angle sensors.

[0099] In this embodiment, the boom monitoring unit: by setting the first inertial swing monitoring point every 5-10 meters along the length of the boom, the swing characteristics of the boom at different positions can be accurately captured, providing comprehensive support for global swing risk assessment. The hook monitoring unit: through the second inertial swing monitoring point, the swing characteristics of the hook, including spatial angle changes, are accurately captured to provide data support for the refined control of the hook swing. Compared with the traditional method that relies on a single point or manual observation, the present invention realizes multi-point real-time monitoring, which can significantly improve the accuracy of swing risk assessment, thereby timely discovering and controlling potential safety hazards.

[0100] Example 3

[0101] This embodiment is explained in Example 1. For details, please refer to Figure 1 , the first alarm module includes an extraction unit, a frequency converter acquisition unit and a first calculation unit;

[0102] The extraction unit is used to extract the boom swing amplitude from the real-time data of the boom. , boom swing cycle and boom swing angle ; and extract the hook swing amplitude in the real-time hook data , hook swing cycle and hook swing angle And the real-time load weight obtained from the dynamic load monitoring point After: data cleaning, missing value processing and dimensionless processing; systematic extraction of boom and hook swing data, as well as dynamic load weight data, after data cleaning, missing value processing and dimensionless processing, to ensure data accuracy and consistency.

[0103] The inverter acquisition unit is used to collect the acceleration power of the inverter and deceleration power .

[0104] The first calculation unit is used to construct an inertial swing risk index IB based on the data collected and processed by the extraction unit and the frequency converter collection unit;

[0105] The specific steps of constructing the Inertia Swing Risk Index IB include:

[0106] S11. Extract the swing amplitude of the boom , boom swing cycle and boom swing angle , the boom inertia swing index is calculated by the following formula :

[0107] ;

[0108] In the formula, Indicates the boom length, Indicates the boom swing angle When the boom swing angle is small (close to horizontal), The value of is close to 1; when the angle is large (close to vertical), The value of is close to 0;

[0109] S12, extract the swing amplitude of the hook , hook swing cycle and hook swing angle , the hook inertia swing index is calculated by the following formula :

[0110] ;

[0111] In the formula, It represents the risk weight coefficient of hook swing, which is determined by load test data or simulation results; Indicates the hook swing angle The sine value of the swing angle is close to 1 when the swing angle is large, indicating that the swing has a greater impact; when the swing angle is small, the sine value is close to 0;

[0112] S13, combined with acceleration power , deceleration power and real-time load weight , the inertial swing risk index IB is calculated by the following formula:

[0113] ;

[0114] In the formula, and represent weight coefficients, and , , .

[0115] In this embodiment, the boom inertia swing index Based on the boom length and the cosine value of the swing angle, when the boom swing angle is small (close to horizontal), the inertial effect of the swing is greater; when the angle is close to vertical, the inertial effect is smaller, and the calculation result is more consistent with the actual operation situation.

[0116] Hook inertia swing index Combining the risk weight coefficient of the hook swing with the sine value of the swing angle, the impact of the swing risk can be significantly amplified when the swing angle is large, providing key warnings for high-risk operations.

[0117] The final inertial swing risk index IB further combines the acceleration power, deceleration power and real-time load weight, and through a comprehensive analysis of multiple weight parameters, forms a quantitative expression of the overall risk to ensure the scientificity and practicality of the early warning indicators.

[0118] Example 4

[0119] This embodiment is explained in Example 3. For details, please refer to Figure 1 The first alarm module further includes a first judgment unit, which is used to preset an inertial swing threshold value X and compare the inertial swing risk index IB with the inertial swing threshold value X to determine whether there is an inertial swing risk, including:

[0120] If the inertial swing risk index IB ≤ the inertial swing threshold value X, it means that the tower crane has no inertial swing risk and operates normally without adjustment;

[0121] If the inertial swing risk index IB> inertial swing threshold X, it means that the tower crane has an inertial swing risk and operates abnormally, triggering the first alarm and generating the first control strategy through the remote control module, including: adjusting and reducing the current acceleration power by 3%-5% And reduce the current deceleration power 3%-5% of the value of the first adjustment parameter is generated.

[0122] In this embodiment, the inertial swing of the boom and hook of the tower crane is mainly caused by rapid acceleration or deceleration during operation. When the acceleration power is too large, a large starting inertia will be generated, resulting in obvious swinging of the boom or hook. Reducing the acceleration power by 3%-5% can slow down the starting speed of the equipment, thereby reducing the accumulation of inertial force, significantly reducing the swing amplitude of the boom and hook, and reducing the risk of swinging of the system due to starting inertia. If the adjustment range is too large, the operating speed of the crane may slow down significantly, affecting the progress of the operation; if the adjustment range is too small, the risk of inertial swing may not be significantly improved. The adjustment range of 3%-5% is a balance value that takes into account both risk reduction and efficiency maintenance, which meets actual engineering needs.

[0123] Example 5

[0124] This embodiment is explained in Example 1. For details, please refer to Figure 1 , the second alarm module includes an environment acquisition unit, a second analysis unit and a second judgment unit;

[0125] The environment acquisition unit is used to collect wind speed data of the actual working environment of the tower crane in real time after the first control strategy is implemented, obtain the wind speed value Fs through the wind speed sensor, and extract the boom swing angle , hook swing angle and real-time load weight After dimensionless processing, the second analysis unit calculates the dynamic load change rate using the following formula: :

[0126] ;

[0127] ;

[0128] ;

[0129] In the formula, Indicates the change in the boom swing angle. Indicates the boom swing angle at the end of the monitoring time, Indicates the boom swing angle at the beginning of the monitoring time; Indicates the change in hook swing angle. Indicates the hook swing angle at the end of the monitoring time. Indicates the hook swing angle at the beginning of the monitoring time; use the angle sensor to monitor the swing angle of the boom or hook in real time. The formula integrates the change value of the boom swing angle , Hook swing angle change value The wind speed value FS reflects the changes in load status in real time from multiple dimensions. Compared with traditional single monitoring parameters (such as load or single swing angle), this comprehensive evaluation method can more accurately identify potential risks. Wind speed changes are a key external factor in the swing of the boom and hook. High wind speed environments are prone to cause larger swing amplitudes and angle fluctuations, further exacerbating the instability of dynamic loads.

[0130] The second judgment unit is used to preset a dynamic load change threshold , to determine whether there is a risk of load fluctuation, including:

[0131] If the dynamic load change rate >Dynamic load change threshold When the load fluctuation risk exists, the second alarm is triggered, and the remote control module generates a second control strategy based on the second alarm, including: further adjusting the current acceleration power to reduce 6%-8% on the first adjustment parameter value. And reduce the current deceleration power 6%-8% of the value of the second adjustment parameter is generated;

[0132] If the dynamic load change rate ≤ Dynamic load change threshold When , it means there is no risk of load fluctuation and continuous monitoring is performed.

[0133] In this embodiment, the dynamic load change rate combines multiple factors such as the swing angle change of the boom and hook and the wind speed, providing an accurate and comprehensive load risk assessment, which is particularly suitable for operation scenarios under complex environmental conditions. On the basis of implementing the first adjustment parameter value (3%-5% power adjustment), when further load fluctuation risks are detected, the second control strategy will further reduce the acceleration power and deceleration power by 6%-8%, thereby more effectively suppressing inertial swing and load fluctuations. Gradually lowering the acceleration and deceleration power can significantly reduce the impact force of the mechanical system during load fluctuations and effectively protect the key components of the tower crane. Through staged and fine-grained adjustments, the equipment instability problem that may be caused by a one-time large-scale power adjustment is avoided. When the dynamic load change rate exceeds the threshold, the triggered second control strategy can respond quickly, further reducing the instability and risk of equipment operation, especially in the case of high wind speed or large swing, to ensure the safety of hoisting operations. Dynamic monitoring and two-layer control strategies (first adjustment parameter value or second adjustment parameter value) ensure that even in the case of severe load fluctuations, the stability of the equipment can be maintained through power optimization to prevent accidents.

[0134] Example 6

[0135] This embodiment is explained in Example 1. For details, please refer to Figure 1 , the compensation evaluation module includes a third acquisition unit and a third calculation unit;

[0136] The third acquisition unit is used to collect the slip frequency of the asynchronous motor of the inverter in real time during operation. and output torque ;

[0137] Output torque It is the actual rotational torque generated during operation; it is measured by a torque sensor.

[0138] Slip frequency It is the difference between the speed of an asynchronous motor and its synchronous speed during operation; an encoder (or incremental encoder) is used to accurately measure the speed of the motor shaft, calculate the actual speed, and compare it with the synchronous speed of the motor to obtain the slip frequency.

[0139] The third calculation unit is used to calculate the output torque and slip frequency , calculate the torque compensation error index using the following formula Slip compensation error index :

[0140] ;

[0141] ;

[0142] in, represents the output torque of the i-th sampling, Indicates the theoretical torque threshold calculated according to the inverter control instruction; represents the slip frequency of the i-th sampling, Indicates the theoretical target slip frequency threshold;

[0143] Indicates the maximum difference between the output torque sampled at the i-th time and the theoretical torque threshold;

[0144] Indicates the maximum difference between the slip frequency sampled at the ith time and the theoretical target slip frequency threshold;

[0145] , , and is the weight, , , , ,and , , , n is the total number of samples.

[0146] The output torque and slip frequency collected in real time by the third acquisition unit are key indicators reflecting the operating status of the asynchronous motor, and can accurately capture power fluctuations and deviations during operation. Slip compensation error index , can accurately quantify the deviation between the actual operating status and the theoretical target, clarify the compensation needs, and improve the targetedness of system adjustment.

[0147] The compensation evaluation module also includes a third judgment unit, which is used to preset a torque abnormality threshold. ; and the torque compensation error index Torque abnormality threshold Compare to determine whether there is any abnormality in the torque, including:

[0148] If the torque compensation error index ≥Torque abnormality threshold , indicating that there is an abnormality in the torque compensation, triggering the third alarm, and the remote control module generates a third control strategy, including: adjusting the motor speed by ±5%-10% to compensate the output torque;

[0149] If the torque compensation error index <Torque abnormality threshold , indicating that there is no abnormality in the torque compensation and monitoring is continued.

[0150] The third judgment unit accurately judges the abnormality of the motor output torque and dynamically generates a compensation control strategy. According to the severity of the torque abnormality, the motor speed is adjusted (±5%-10%) to achieve real-time compensation for the torque output and avoid the interference of abnormal torque on the lifting operation. When the torque is abnormal, the motor speed is adjusted to reduce the shaking of the boom or hook caused by torque deviation, reduce equipment overload or long-term vibration caused by torque abnormality, protect key components, and extend equipment life.

[0151] The compensation evaluation module further includes a fourth judgment unit, which is used to preset a slip abnormality threshold. , and the slip compensation error index Slippage Abnormal Threshold Compare to determine whether there is any abnormality in slip compensation, including:

[0152] If the slip compensation error index ≥ Slippage Abnormal Threshold , it indicates that there is an abnormality in the slip compensation, triggering the fourth alarm, and the remote control module generates a fourth control strategy, including: reducing the slip frequency by 5%-10% Make corrections to avoid instability caused by over-adjustment;

[0153] If the slip compensation error index <Slippage abnormal threshold , it means that there is no abnormality in slip compensation and monitoring is continued.

[0154] If the slip compensation error index If there is an anomaly, the fourth control strategy will correct the deviation by adjusting the slip frequency (reducing it by 5%-10%). This helps to avoid instability caused by over-adjustment and maintain smooth operation of the system. When correcting the slip compensation, the adjustment range is controlled (5%-10%) to avoid excessive fluctuations or interference in motor performance and crane operation. If the slip compensation anomaly is not corrected in time, it may cause motor overload, unstable operation or even equipment damage. The fourth judgment unit reduces such risks and ensures the safety of the crane by correcting the slip compensation error in real time. Through accurate slip frequency adjustment, it helps to ensure that the tower crane maintains stable operation under various workloads and reduce unnecessary shaking of the boom or hook.

[0155] The threshold is set to facilitate comparison. The size of the threshold depends on the amount of sample data and the number of bases set by technicians in this field for each group of sample data; as long as it does not affect the proportional relationship between the parameter and the quantized value.

[0156] The above formulas are obtained by collecting a large amount of data for software simulation and selecting a formula that is close to the actual value. The coefficients in the formula are set by technical personnel in this field according to actual conditions. The above is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited to this. Any technical personnel familiar with the technical field within the technical scope disclosed by the present invention, according to the technical solution and the inventive concept of the present invention, make equivalent replacement or change, which should be covered within the protection scope of the present invention.

Claims

1. A frequency converter remote control system, characterized in that: It includes a region division module, a first alarm module, a second alarm module, a compensation evaluation module and a remote control module; The area division module is used to divide the key monitoring area during the operation of the tower crane into multiple sub-areas, and set an inertial swing monitoring point and a dynamic load monitoring point in each sub-area; The first alarm module is used to collect the swing amplitude, swing period and swing angle of the boom or hook in real time according to the inertial swing monitoring point, and collect the acceleration power of the inverter and deceleration power And collect the real-time load weight of tower cranes , to construct the Inertial Swing Risk Index IB; A pre-set inertial swing threshold value X is provided. When the inertial swing risk index IB exceeds the inertial swing threshold value X, a first alarm is triggered and a first control strategy is generated through a remote control module to reduce the swing risk. The second alarm module, after triggering the first alarm and optimizing, collects wind speed data and dynamic load changes of the actual operating environment of the tower crane in real time, and constructs a dynamic load change rate ;Preset dynamic load change threshold , when the dynamic load change rate Exceeding the dynamic load change threshold When a second alarm is triggered, the remote control module generates a second control strategy for making corrections on the first control strategy; The compensation evaluation module is used to monitor the slip compensation and torque compensation status of the inverter in real time during operation, and collect the real-time output torque of the motor. and slip frequency , construct the torque compensation error index Slip compensation error index And evaluate, if it is judged that the torque compensation is abnormal, trigger the third alarm; If it is determined that there is an abnormality in the slip compensation, the fourth alarm is triggered; The remote control module is used to generate corresponding control strategies according to the first alarm, the second alarm, the third alarm and the fourth alarm, and remotely adjust the operating state of the inverter, including power regulation, torque correction and slip frequency adjustment.

2. A frequency converter remote control system according to claim 1, characterized in that: The area division module includes a boom monitoring unit, a hook monitoring unit and a load monitoring unit; The boom monitoring unit is used to set a first inertial swing monitoring point at a certain interval of the boom length, including 5-10 meters, and collect real-time data of the boom in real time through an acceleration sensor or a gyroscope, including: Boom swing range : Maximum offset distance of boom swing; Boom swing cycle : A complete cycle time of boom swing; Boom swing angle : Change of the horizontal angle of the boom swing; The hook monitoring unit is responsible for setting a second inertial swing monitoring point at the hook position, and collecting real-time hook data in real time through an acceleration sensor or a gyroscope, including: Hook swing range : Maximum offset distance of hook swing; Hook swing cycle : A complete cycle time of hook swing; Hook swing angle : Change of hook swing space angle; The load monitoring unit is used to set a dynamic load monitoring point on the hook to install a weight sensor to collect and obtain real-time load weight. .

3. A frequency converter remote control system according to claim 2, characterized in that: The first alarm module includes an extraction unit, a frequency converter acquisition unit and a first calculation unit; The extraction unit is used to extract the boom swing amplitude in the real-time data of the boom. , boom swing cycle and boom swing angle ; and extract the hook swing amplitude in the real-time hook data , hook swing cycle and hook swing angle And the real-time load weight obtained from the dynamic load monitoring point After: data cleaning, missing value processing and dimensionless processing; The frequency converter acquisition unit is used to collect the acceleration power of the frequency converter and deceleration power .

4. A frequency converter remote control system according to claim 3, characterized in that: The first calculation unit is used to construct an inertial swing risk index IB based on the data collected and processed by the extraction unit and the frequency converter collection unit; The specific steps of constructing the inertial swing risk index IB include: S11. Extract the swing amplitude of the boom , boom swing cycle and boom swing angle , the boom inertia swing index is calculated by the following formula : ； In the formula, Indicates the boom length, Indicates the boom swing angle The cosine of ; S12, extract the swing amplitude of the hook , hook swing cycle and hook swing angle , the hook inertia swing index is calculated by the following formula : ； In the formula, It represents the risk weight coefficient of hook swing, which is determined by load test data or simulation results; Indicates the hook swing angle The sine value of ; S13, combined with acceleration power , deceleration power and real-time load weight , the inertial swing risk index IB is calculated by the following formula: ； In the formula, and represent weight coefficients, and , , .

5. A frequency converter remote control system according to claim 4, characterized in that: The first alarm module further includes a first judgment unit, which is used to preset an inertial swing threshold value X and compare the inertial swing risk index IB with the inertial swing threshold value X to determine whether there is an inertial swing risk, including: If the inertial swing risk index IB ≤ the inertial swing threshold value X, it means that the tower crane has no inertial swing risk and operates normally without adjustment; If the inertial swing risk index IB> inertial swing threshold X, it means that the tower crane has an inertial swing risk and operates abnormally, triggering the first alarm and generating the first control strategy through the remote control module, including: adjusting and reducing the current acceleration power by 3%-5% And reduce the current deceleration power 3%-5% of the value of the first adjustment parameter is generated.

6. A frequency converter remote control system according to claim 5, characterized in that: The second alarm module includes an environment collection unit, a second analysis unit and a second judgment unit; The environment acquisition unit is used to collect wind speed data of the actual working environment of the tower crane in real time after the first control strategy is implemented, obtain the wind speed value Fs, and extract the boom swing angle , hook swing angle and real-time load weight After dimensionless processing, the second analysis unit calculates the dynamic load change rate using the following formula: : ； ； ； In the formula, Indicates the change in the boom swing angle. Indicates the boom swing angle at the end of the monitoring time, Indicates the boom swing angle at the beginning of the monitoring time; Indicates the change in hook swing angle. Indicates the hook swing angle at the end of the monitoring time. Indicates the hook swing angle at the beginning of the monitoring time; use the angle sensor to monitor the swing angle of the boom or hook in real time.

7. A frequency converter remote control system according to claim 6, characterized in that: The second judgment unit is used to preset a dynamic load change threshold , to determine whether there is a risk of load fluctuation, including: If the dynamic load change rate >Dynamic load change threshold When the load fluctuation risk exists, the second alarm is triggered, and the remote control module generates a second control strategy based on the second alarm, including: further adjusting the current acceleration power to reduce 6%-8% on the first adjustment parameter value. And reduce the current deceleration power 6%-8% of the value of the second adjustment parameter is generated; If the dynamic load change rate ≤ Dynamic load change threshold When , it means there is no risk of load fluctuation and continuous monitoring is performed.

8. A frequency converter remote control system according to claim 1, characterized in that: The compensation evaluation module includes a third acquisition unit and a third calculation unit; The third acquisition unit is used to collect the slip frequency of the asynchronous motor of the inverter in real time during operation. and output torque ; Output torque It is the actual rotational torque generated during operation; Slip frequency It is the difference between the speed of the asynchronous motor and the synchronous speed during operation; The third calculation unit is used to calculate the output torque and slip frequency , calculate the torque compensation error index using the following formula Slip compensation error index : ； ； in, represents the output torque of the i-th sampling, Indicates the theoretical torque threshold calculated according to the inverter control instruction; represents the slip frequency of the i-th sampling, Indicates the theoretical target slip frequency threshold; Indicates the maximum difference between the output torque sampled at the i-th time and the theoretical torque threshold; Indicates the maximum difference between the slip frequency sampled at the ith time and the theoretical target slip frequency threshold; , , and is the weight, , , , ,and , , , n is the total number of samples.

9. A frequency converter remote control system according to claim 8, characterized in that: The compensation evaluation module further includes a third judgment unit, which is used to preset a torque abnormality threshold. ; The torque compensation error index Torque abnormality threshold Compare to determine whether there is any abnormality in the torque, including: If the torque compensation error index ≥Torque abnormality threshold , indicating that there is an abnormality in the torque compensation, triggering the third alarm, and the remote control module generates a third control strategy, including: adjusting the motor speed by ±5%-10% to compensate the output torque; If the torque compensation error index <Torque abnormality threshold , indicating that there is no abnormality in the torque compensation and monitoring is continued.

10. A frequency converter remote control system according to claim 9, characterized in that: The compensation evaluation module further includes a fourth judgment unit, wherein the fourth judgment unit is used to preset a slip abnormality threshold. , and the slip compensation error index Slippage Abnormal Threshold Compare to determine whether there is any abnormality in slip compensation, including: If the slip compensation error index ≥ Slippage Abnormal Threshold , it indicates that there is an abnormality in the slip compensation, triggering the fourth alarm, and the remote control module generates a fourth control strategy, including: reducing the slip frequency by 5%-10% Make corrections to avoid instability caused by over-adjustment; If the slip compensation error index <Slippage abnormal threshold , it means that there is no abnormality in slip compensation and monitoring is continued.

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