Crown block wheel synchronous walking method based on frequency converter control

Abstract

The invention provides a crown block wheel synchronous walking method based on frequency converter control, and belongs to the technical field of control, the two sides of a crown block of a bridge girder erection machine for dismantling a girder body are respectively provided with two motors, each motor drives one wheel of the crown block, and the rotating speeds of the two motors are respectively controlled through two frequency converters; the rotating speeds of the wheels on the two sides are consistent; a high-precision sensor is installed on a crown block, the installation position of the sensor is optimized, it is ensured that the sensor can accurately detect the rotating speed and position changes of wheels of the crown block, a high-speed data transmission mode is adopted, it is ensured that data transmission between the sensor and a controller is not delayed, and the controller can adjust output of a frequency converter in time; and the rotating speeds of the two motors are always kept consistent, so that the synchronous walking of two wheels of the crown block of the bridge girder erection machine for dismantling the girder body is realized.

Description

Technical Field

[0001] The invention belongs to the field of control technology, and in particular relates to a method for synchronous movement of overhead wheels based on frequency converter control. Background Art

[0002] The way in which the bridge erection machine performs beam dismantling construction operations is as described in the prior art solution in patent publication number "CN114541267B" where the overhead crane of the bridge erection machine assists the dismantling device of the bridge erection machine in performing beam dismantling construction operations.

[0003] Overhead cranes play a crucial role during the dismantling of bridge cranes. They are used to transport materials to the dismantling device of bridge cranes during beam removal operations. However, in actual use, the wheels on both sides of the overhead crane often rotate at different speeds due to mechanical wear and uneven loads. This can cause the wheels to derail, seriously impacting the safety and efficiency of the overhead crane. Existing solutions often rely on mechanical adjustments and manual intervention, but these methods are not only time-consuming and labor-intensive, but also difficult to precisely control. Therefore, a method that can automatically adjust and ensure consistent wheel speeds on both sides is urgently needed.

[0004] Although the existing method of synchronous travel of overhead crane wheels based on frequency converter control can monitor and adjust the motor speed in real time through the frequency converter and sensors, it has the following technical defects in actual application:

[0005] 1. Sensor installation position and accuracy issues: The installation position and accuracy of the sensor directly affect the accuracy of the speed and position data. If the sensor is installed in an improper position or the accuracy is insufficient, the data received by the controller will be inaccurate, thereby affecting the adjustment effect of the inverter and failing to effectively ensure the synchronous movement of the wheels on both sides.

[0006] 2. Data transmission delay problem: There may be delays in data transmission between the sensor and the controller, especially in data transmission under high load or complex environments. The delay will cause the controller to be unable to adjust the output frequency of the inverter in time, affecting the effect of synchronous walking. Summary of the Invention

[0007] In order to solve the defects in the existing technology, the present invention provides a method for synchronous movement of overhead crane wheels based on frequency converter control, ensuring that the wheels on both sides of the overhead crane of the bridge erection machine used for beam dismantling move synchronously, so as to solve the problem of inconsistent speed caused by improper sensor installation position and data transmission delay in the existing technology, and further improve the operation safety and efficiency of the overhead crane.

[0008] The present invention utilizes the following technical solutions.

[0009] A method for synchronous movement of overhead wheels based on frequency converter control, comprising:

[0010] Step 1: Install two motors on both sides of the overhead crane of the bridge erection machine used for beam removal. Each motor drives one wheel of the overhead crane. The speeds of the two motors are controlled by two frequency converters.

[0011] Step 2: Install sensors on the overhead crane and optimize their installation locations. The sensors monitor the pulse count and position of the two wheels of the overhead crane in real time and transmit the information to the controller.

[0012] Step 3: The controller receives the number of pulses transmitted by the sensor and adjusts the inverter's adjustment amount based on the speed calculated from the number of pulses to dynamically adjust the motor's speed.

[0013] Step 4: Use high-speed data transmission to ensure that there is no delay in data transmission between the sensor and the controller.

[0014] Preferably, in step 1, the output ends of the two motors are respectively connected to the two wheel shafts of the overhead crane of the bridge erection machine for beam dismantling, the two frequency converters are respectively electrically connected to the two motors, and the two frequency converters are both connected to the controller.

[0015] Preferably, in step 2, the sensor includes an encoder and a position sensor, and the encoder and the position sensor are used to respectively collect the pulse number and position of the wheel and transmit them to the controller.

[0016] Preferably, in step 2, at a set time interval The number of pulses received by the controller from the encoder is , the encoder generates pulses, and the controller obtains the wheel speed value based on this The formula is:

[0017] .

[0018] Preferably, in step 2, the method for optimizing the installation position of the sensor specifically includes:

[0019] The encoder in the sensor is installed at the end of the wheel axle. The encoder is mounted on a stable bracket and keeps a reasonable distance from the axle, which is 1-2 cm.

[0020] The position sensor in the sensor is installed on the side of the wheel, keeping a certain distance from the wheel, and the position sensor should be installed on a fixed bracket;

[0021] The acceleration sensor in the sensor is installed next to the wheel axle, and the acceleration sensor is fixed on the bracket of the wheel axle;

[0022] Preferably, in step 2, the sensor is installed as follows:

[0023] Calibration: After the sensor is installed, it is calibrated to ensure that the zero offset and sensitivity of the sensor meet the requirements. The calibration process includes static calibration and dynamic calibration. Static calibration is used to correct the zero offset, and dynamic calibration is used to correct the accuracy of the sensor under dynamic conditions.

[0024] Protection: Install a protective cover at the sensor installation location.

[0025] Preferably, in step 2, the static calibration includes: calibrating the sensor to obtain a zero offset of the sensor as Unit, then add bias correction when processing the data collected by the sensor, the corrected data for: ,in This is the data before sensor calibration;

[0026] Dynamic correction: Use the Kalman filter to combine the data collected by the statically corrected sensor and the model of the control system to perform dynamic error correction.

[0027] Preferably, in step 3, the adjustment amount of the frequency converter is adjusted according to the speed The algorithm is a synchronous walking algorithm, and its formula is:

[0028]

[0029] in, 、 、 are proportional coefficient, integral coefficient, and differential coefficient respectively; is the speed error, the speed error is the time The preset working speed of the wheel minus the controller at the moment The difference between the calculated rotation speeds is is the speed error change rate.

[0030] Preferably, in step 4, adopting a high-speed data transmission method includes: adopting optical fiber communication or wireless high-speed communication between the sensor and the controller.

[0031] Preferably, the method for synchronous movement of overhead crane wheels based on frequency converter control further includes:

[0032] Encoder fault detection: The encoder fault detection module is integrated into the controller to monitor the working status of the encoder in real time. When an encoder fault is detected, the fault protection mechanism is triggered in real time to stop the motor and issue a warning signal;

[0033] Inverter fault detection: The inverter fault detection module is integrated into the controller to monitor the working status of the inverter in real time. When an inverter fault is detected, the fault protection mechanism is triggered in real time to stop the motor and issue a warning signal;

[0034] Fault protection mechanism: When an encoder or inverter fault is detected, the controller automatically switches to safe mode, stops the motor or inverter, and notifies maintenance personnel through an alarm signal.

[0035] Preferably, an encoder fault detection module is integrated into the controller to monitor the working status of the encoder in real time. The specific steps include:

[0036] Data consistency check: By comparing the encoder data, detect the inconsistency between the data to determine whether the encoder is faulty;

[0037] Signal strength check: Monitors the strength of the encoder signal. If the signal strength is lower than the set threshold, the encoder may be damaged or poorly connected.

[0038] Preferably, a frequency converter fault detection module is integrated into the controller to monitor the working status of the frequency converter in real time. The specific steps include:

[0039] Current detection: By monitoring the current output by the inverter, it is determined whether the inverter is in normal working condition. If abnormal current fluctuations are detected, it is determined that the inverter is faulty.

[0040] Temperature monitoring: monitor the temperature of the inverter. If the temperature exceeds the preset safety range, it indicates that the inverter is overheating.

[0041] Communication check: By checking the communication status between the inverter and the controller, it is determined whether the inverter is working normally. If the communication is interrupted or the data packet is lost, it indicates that the inverter is faulty.

[0042] Preferably, the fault protection mechanism is:

[0043] When an encoder or inverter fault is detected, the controller automatically switches to safe mode, stops the motor to prevent further damage to the equipment, and notifies maintenance personnel through an alarm signal. The specific steps include:

[0044] Stop the motor in real time: When the encoder or inverter fault detection module is triggered, the controller sends a stop signal in real time to stop the motor;

[0045] Issue warning signal: Through the sound and light alarm or other warning devices connected to the controller, notify the maintenance personnel that the controller has failed and needs to be inspected and repaired;

[0046] Record fault information: The controller automatically records the time, type and data before the fault for subsequent analysis and diagnosis;

[0047] Entering safe mode: Before troubleshooting, the controller enters safe mode and prohibits the overhead crane from continuing to operate to ensure safety.

[0048] The beneficial effects of the present invention are as follows:

[0049] Two motors are installed on both sides of the overhead crane of the bridge-building machine used for beam dismantling. Each motor drives one wheel of the overhead crane. The rotation speeds of the two motors are controlled separately by two frequency converters to ensure that the rotation speeds of the wheels on both sides are consistent. High-precision sensors are installed on the overhead crane, and the installation positions of the sensors are optimized to ensure that the sensors can accurately detect the rotation speed and position changes of the overhead crane wheels. High-speed data transmission is used to ensure that there is no delay in data transmission between the sensor and the controller, so that the controller can adjust the output of the frequency converter in time to ensure that the rotation speeds of the two motors are always consistent, thereby realizing the synchronous movement of the two wheels of the overhead crane of the bridge-building machine used for beam dismantling. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 The present invention is a flowchart of a method for synchronous movement of overhead wheels based on frequency converter control. DETAILED DESCRIPTION

[0051] Although the existing method of synchronous travel of overhead crane wheels based on frequency converter control can monitor and adjust the motor speed in real time through the frequency converter and sensors, it has the following technical defects in actual application:

[0052] Issues with sensor installation location and accuracy; issues with data transmission delay.

[0053] The present invention optimizes the installation position of the sensor to ensure that the sensor can accurately detect the rotation speed and position changes of the wheels of the overhead crane, adopts a high-speed data transmission method to ensure that the data transmission between the sensor and the controller is delay-free, so that the controller can adjust the output of the inverter in time to ensure that the rotation speeds of the two motors are always consistent, thereby realizing the synchronous movement of the two wheels of the overhead crane of the bridge crane used for beam dismantling.

[0054] To make the objectives, technical solutions, and advantages of the present invention more clear, the following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely express the technical solutions of the present invention. The embodiments expressed in this application are only part of the embodiments of the present invention, not all of the embodiments. Based on the spirit of the present invention, other embodiments obtained by ordinary technicians in this field without making creative work are all within the scope of protection of the present invention.

[0055] like Figure 1 As shown, a method for synchronous movement of overhead wheels based on frequency converter control includes:

[0056] Step 1: Install two motors on each side of the overhead crane used for beam removal. Each motor drives one wheel of the overhead crane. Use two frequency converters to control the speed of the two motors to ensure that the speed of the wheels on both sides is consistent.

[0057] In a preferred but non-limiting embodiment of the present invention, in step 1, the output ends of the two motors are respectively connected to the two wheel shafts of the overhead crane of the bridge erection machine used for beam removal, two frequency converters are respectively electrically connected to the two motors, and both frequency converters are connected to a controller. The controller may be a PLC.

[0058] Two high-performance AC motors are installed on either side of the overhead crane, each driving a wheel. The motors should be selected with high precision and reliability in mind to ensure long-term operational stability and precise control. The speeds of the two motors are controlled separately by frequency converters. The frequency converters should have high frequency response and high-precision regulation, enabling real-time adjustment of the motor speeds to ensure consistent wheel speeds on both sides. The frequency converters should also include fault detection and protection features to enhance system safety.

[0059] Assume that an overhead crane needs to stably transport heavy loads for an extended period of time. Therefore, two high-performance AC motors are installed on either side of the crane. Each motor drives a wheel. The motor selection is based on a combination of load and reliability considerations. For example, an ABBAC80 motor is selected to ensure high precision and reliability.

[0060] Step 2: Install a high-precision sensor on the overhead crane and optimize its installation location to ensure that the sensor can accurately detect the rotational speed and position changes of the overhead crane's wheels. The sensor monitors the pulse count and position of the overhead crane's two wheels in real time and transmits this information to the controller.

[0061] ABB ACS880 frequency converters are used to control the speed of the two motors. These converters offer high-precision regulation, adjusting the output frequency in real time based on controller instructions to ensure consistent wheel speeds on both sides. For example, when the target speed is set at 500 rpm, the converter quickly adjusts the output frequency to the corresponding speed.

[0062] In a preferred but non-limiting embodiment of the present invention, in step 2, high-precision sensors are installed on the overhead crane to monitor the rotational speed and position of the wheels on both sides in real time. These sensors should have high sampling rates and low latency to ensure real-time and accurate data. These sensors may include encoders, position sensors, and accelerometers, which are used to collect wheel pulse counts, position, and acceleration, respectively, and transmit these data to a controller for comprehensive wheel status monitoring.

[0063] High-precision sensors, including encoders and position sensors, are installed on the overhead crane. In a preferred but non-limiting embodiment of the present invention, in step 2, at set time intervals The number of pulses received by the controller from the encoder is , the encoder generates pulses, and the controller obtains the wheel speed value based on this The formula is:

[0064] .

[0065] In a preferred but non-limiting embodiment of the present invention, in step 2, the method for optimizing the installation position of the sensor specifically includes:

[0066] To ensure that the sensor can accurately detect the wheel's rotational speed and position changes, the encoder in the sensor is installed at the end of the wheel axle to ensure that the sensor and the axle's rotational speed are synchronized. To reduce the impact of mechanical vibration, the encoder should be installed on a stable bracket and maintain a reasonable distance from the axle, which is generally 1-2 cm.

[0067] The position sensor in the sensor is installed on the side of the wheel, keeping a certain distance from the wheel (usually 1-2cm) to reduce external interference. The position sensor should be installed on a fixed bracket to ensure its position is stable;

[0068] The accelerometer in the sensor is installed next to the axle to monitor the vibration and acceleration of the axle. The accelerometer should be fixed to the bracket of the axle to ensure its stability and reliability.

[0069] In a preferred but non-limiting embodiment of the present invention, in step 2, the sensor is installed as follows:

[0070] Calibration: After the sensor is installed, it is calibrated to ensure that the zero offset and sensitivity of the sensor meet the requirements. The calibration process includes static calibration and dynamic calibration. Static calibration is used to correct the zero offset, and dynamic calibration is used to correct the accuracy of the sensor under dynamic conditions.

[0071] Protection: Install a protective cover at the sensor installation location to protect the sensor from dust, moisture, and mechanical damage. The protective cover should be made of weather-resistant material to ensure its reliability in harsh environments.

[0072] In a preferred but non-limiting embodiment of the present invention, in step 2, the static calibration includes: calibrating the sensor to obtain a zero offset of the sensor. Unit, then add bias correction when processing the data collected by the sensor, the corrected data for: ,in This is the data before sensor calibration;

[0073] For example, the data collected by the sensor at a certain moment, that is, the data before correction (y[n] = 110), has a zero point offset of 5 units. The corrected signal is: [

[0075] y'[n] = 110 - 5 = 105 ]

[0077] Dynamic correction: Using the Kalman filter, combined with the statically corrected sensor data and the control system model, dynamic error correction is performed. For example, assuming the system model is:

[0078] \begin{align*}

[0079] x[n] &= F x[n-1] + B u[n] \\

[0080] y[n] &= H x[n] + v[n]

[0081] \end{align*}

[0082] Where (x) represents the state vector, (F) is the set state coefficient, (B) is the set input coefficient, (u) is the input signal, (H) is the set observation coefficient, and (v) is the observation noise.

[0083] Assuming (F = 1), (B = 1), (H = 1), and assuming that the observation noise (v[n]) is Gaussian noise with a mean of 0 and a variance of 0.5, then correction is performed through the Kalman filter:

[0084] Assume that the initial state (x[0]) is 100, the initial covariance (P[0]) is 1, the observation value (y[1] = 105), and the control input (u[1] = 1), then:

[0085] \begin{align*}

[0086] \hat{x}[1|0] &= F \hat{x}[0|0] + B u[1] = 1 \cdot 100 + 1 \cdot 1= 101 \\

[0087] P[1|0] &= FP[0|0] F^T + Q = 1 \cdot 1 \cdot 1 + 0.1 = 1.1 \\

[0088] K[1] &= \frac{P[1|0]}{P[1|0] + R} = \frac{1.1}{1.1 + 0.5} = \frac{1.1}{1.6} = 0.6875 \\

[0089] \hat{x}[1] &= \hat{x}[1|0] + K[1] (y[1] - H \hat{x}[1|0]) = 101 +0.6875 \cdot (105 - 101) = 101 + 0.6875 \cdot 4 = 103.75 \\

[0090] P[1] &= (1 - K[1]) P[1|0] = (1 - 0.6875) \cdot 1.1 = 0.359375

[0091] \end{align*}

[0092] The corrected signal is:

[0093] x[1]=103.75.

[0094] Step 3: The controller receives the pulse number and position transmitted by the sensor and adjusts the inverter's adjustment amount according to the speed calculated from the pulse number to dynamically adjust the motor's speed.

[0095] The controller receives data transmitted by the sensors and processes it in real time. It should have high-performance computing capabilities and low-latency data processing capabilities, enabling rapid response and adjustment of the inverter's output frequency. The controller should also have data storage and analysis capabilities to record and analyze historical data and further optimize the control algorithm.

[0096] Based on a preset synchronous travel algorithm, the controller calculates and adjusts the inverter output in real time to ensure consistent motor speeds on both sides. This synchronous travel algorithm should consider various factors, such as load variations and mechanical wear, to achieve dynamic adjustment. Advanced control strategies, such as optimized PID control, fuzzy control, or adaptive control, can be employed to improve control accuracy and response speed.

[0097] In a preferred but non-limiting embodiment of the present invention, in step 3, the adjustment amount of the frequency converter is adjusted according to the speed. The algorithm is a synchronous walking algorithm, and its formula is:

[0098] The controller uses a PID control strategy to calculate the correction value in real time using the error between the motor speeds on both sides and the error change. The adjustment value can be calculated using the following formula:

[0099]

[0100] in, 、 、 are proportional coefficient, integral coefficient, and differential coefficient respectively; is the speed error, the speed error is the time The preset working speed of the wheel minus the controller at the moment The difference between the calculated rotation speeds is is the speed error change rate.

[0101] This adjustment is added to the current inverter output, dynamically adjusting the motor speed to ensure that the two wheels always operate in sync.

[0102] Step 4: Use high-speed data transmission to ensure that there is no delay in data transmission between the sensor and the controller, so that the controller can adjust the output of the inverter in time to ensure that the speeds of the two motors are always consistent, thereby achieving synchronous movement of the two wheels of the overhead crane used for beam removal.

[0103] In a preferred but non-limiting embodiment of the present invention, in step 4, using a high-speed data transmission method includes: using optical fiber communication or wireless high-speed communication (such as 5G) between the sensor and the controller to ensure that the data transmission between the sensor and the controller is delay-free.

[0104] Using fiber optic communication technology ensures high-speed and delay-free data transmission. Fiber optic communication has the following advantages:

[0105] High-speed transmission: Fiber optic communication can achieve a transmission rate of up to 1 Gbps, ensuring real-time data transmission.

[0106] Low latency: The transmission latency of fiber-optic communication is very low, usually at the microsecond level, ensuring the real-time nature of data.

[0107] Anti-interference: Fiber optic communication is not affected by electromagnetic interference and is suitable for high noise conditions in industrial environments.

[0108] When optical fiber cannot be used, wireless high-speed communication technologies, such as 5G communication, are used to ensure the stability and real-time performance of data transmission. 5G communication has the following advantages:

[0109] High-speed transmission: 5G communication can achieve a transmission rate of up to 10 Gbps, ensuring real-time transmission of data.

[0110] Low latency: The transmission latency of 5G communication is very low, usually in the range of 1-10 milliseconds, ensuring the real-time nature of data.

[0111] High reliability: 5G networks have high reliability and low packet loss rates, making them suitable for real-time data transmission in industrial control systems.

[0112] By adopting the above-mentioned high-speed data transmission technology, data transmission between the sensor and the controller is ensured to be delay-free. The controller can adjust the output of the inverter in a timely manner, so that the speed of the motors on both sides is always consistent.

[0113] The above method can effectively solve the problem of derailment caused by inconsistent rotation speed of the overhead crane wheels, thereby improving the operation safety and efficiency of the overhead crane.

[0114] Although the inverter-controlled overhead crane wheel synchronous travel method of the present invention can achieve speed synchronization to a certain extent, it has deficiencies in fault detection and protection mechanisms, which are mainly manifested in the following points:

[0115] 1. Insufficient encoder fault detection: Existing controllers often lack real-time detection of encoder faults, resulting in an inability to take timely protective measures when the encoder fails.

[0116] 2. Lack of inverter fault detection: As the core component of the controller, the inverter's failure may cause the motor's dynamic adjustment to fail. The existing system lacks an effective inverter fault detection and protection mechanism.

[0117] After improvement, the present invention can activate the protection mechanism in real time when the encoder fails or the frequency converter fails, thereby preventing serious equipment failure and further improving the operation safety and reliability of the overhead crane.

[0118] In a preferred but non-limiting embodiment of the present invention, the method for synchronous movement of overhead wheels based on frequency converter control further includes:

[0119] Encoder fault detection: An encoder fault detection module is integrated into the controller to monitor the encoder's working status in real time. When an encoder fault is detected, the fault protection mechanism is triggered in real time, stopping the motor and issuing a warning signal; the warning signal is displayed on a display connected to the controller.

[0120] Inverter fault detection: The inverter fault detection module is integrated into the controller to monitor the working status of the inverter in real time. When an inverter fault is detected, the fault protection mechanism is triggered in real time to stop the motor and issue a warning signal;

[0121] Fault protection mechanism: When an encoder or inverter fault is detected, the controller automatically switches to safe mode, stops the motor or inverter to prevent further damage to the equipment, and notifies maintenance personnel through an alarm signal.

[0122] Through encoder fault detection: The encoder fault detection module is integrated into the controller to monitor the working status of the encoder in real time. When an encoder fault is detected, the protection mechanism is immediately triggered to stop the motor operation and issue a warning signal.

[0123] Through inverter fault detection:

[0124] Enhanced inverter fault detection module: Add the function of monitoring the inverter internal faults in the inverter fault detection module, including but not limited to temperature monitoring, internal circuit status monitoring and communication status monitoring.

[0125] Multi-parameter comprehensive judgment: Through comprehensive analysis of multiple parameters such as the voltage, current, temperature and communication status of the inverter, comprehensive monitoring of the inverter's internal faults can be achieved.

[0126] Through the fault protection mechanism: When an encoder or inverter fault is detected, the controller automatically switches to safe mode, stops the motor to prevent further damage to the equipment, and notifies maintenance personnel through an alarm signal.

[0127] The above-mentioned improvement plan can effectively solve the problem of derailment caused by inconsistent wheel speed of the overhead crane, and immediately activate the protection mechanism when a complex fault occurs in the inverter, further improving the operation safety and reliability of the overhead crane.

[0128] In a preferred but non-limiting embodiment of the present invention, an encoder fault detection module is integrated into the controller to monitor the working status of the encoder in real time. The specific steps include:

[0129] Data consistency check: By comparing the encoder data, the inconsistency between the data is detected to determine whether the encoder has failed. For example, if the speed difference detected by the two encoders exceeds a certain threshold (such as 10%), it is determined that the encoder may be faulty.

[0130] Signal strength check: monitors the encoder signal strength. If the signal strength is lower than the set threshold, the encoder may be damaged or poorly connected.

[0131] Self-test function: The encoder self-test function is performed regularly to check the working status of the encoder by sending test signals and receiving responses.

[0132] In a preferred but non-limiting embodiment of the present invention, a frequency converter fault detection module is integrated into the controller to monitor the working status of the frequency converter in real time. The specific steps include:

[0133] Current detection: By monitoring the current output by the inverter, it is determined whether the inverter is in normal working condition. If abnormal current fluctuations (such as sudden changes or overload) are detected, it is determined that the inverter may be faulty;

[0134] Temperature monitoring: Monitor the temperature of the inverter. If the temperature exceeds the preset safety range, it means that the inverter may be overheated and protective measures should be taken immediately;

[0135] Communication check: By checking the communication status between the inverter and the controller, it is determined whether the inverter is working normally. If the communication is interrupted or the data packet is lost, it means that the inverter may be faulty.

[0136] In a preferred but non-limiting embodiment of the present invention, the fault protection mechanism is:

[0137] When an encoder or inverter fault is detected, the controller automatically switches to safe mode, stops the motor to prevent further damage to the equipment, and notifies maintenance personnel through an alarm signal. The specific steps include:

[0138] Stop the motor in real time: When the encoder or inverter fault detection module is triggered, the controller sends a stop signal in real time to stop the motor;

[0139] Issue warning signal: Through the sound and light alarm or other warning devices connected to the controller, notify the maintenance personnel that the controller has failed and needs to be inspected and repaired;

[0140] Record fault information: The controller automatically records the time, type and data before the fault for subsequent analysis and diagnosis;

[0141] Entering safe mode: Before troubleshooting, the controller enters safe mode and prohibits the overhead crane from continuing to operate to ensure safety.

[0142] Through the above-mentioned fault detection and protection module, the protection mechanism can be activated in real time when the encoder fails or the inverter fails, preventing serious equipment failures and improving the operating safety and reliability of the overhead crane.

[0143] The beneficial effects of the present invention are as follows:

[0144] Two motors are installed on both sides of the overhead crane of the bridge-building machine used for beam dismantling. Each motor drives one wheel of the overhead crane. The rotation speeds of the two motors are controlled separately by two frequency converters to ensure that the rotation speeds of the wheels on both sides are consistent. High-precision sensors are installed on the overhead crane, and the installation positions of the sensors are optimized to ensure that the sensors can accurately detect the rotation speed and position changes of the overhead crane wheels. High-speed data transmission is used to ensure that there is no delay in data transmission between the sensor and the controller, so that the controller can adjust the output of the frequency converter in time to ensure that the rotation speeds of the two motors are always consistent, thereby realizing the synchronous movement of the two wheels of the overhead crane of the bridge-building machine used for beam dismantling.

[0145] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not deviate from the spirit and scope of the present invention should be covered within the protection space of the claims of the present invention.

Claims

1. A method for synchronous movement of overhead wheels based on frequency converter control, characterized in that: include: Step 1: Install two motors on both sides of the overhead crane of the bridge erection machine used for beam removal. Each motor drives one wheel of the overhead crane. The speeds of the two motors are controlled by two frequency converters. Step 2: Install sensors on the overhead crane and optimize their installation locations. The sensors monitor the pulse count and position of the two wheels of the overhead crane in real time and transmit the information to the controller. Step 3: The controller receives the number of pulses transmitted by the sensor and adjusts the inverter's adjustment amount based on the speed calculated from the number of pulses to dynamically adjust the motor's speed. Step 4: Use high-speed data transmission to ensure that there is no delay in data transmission between the sensor and the controller; In step 3, adjust the inverter's adjustment amount according to the speed The algorithm is a synchronous walking algorithm, and its formula is: in, 、 、 are proportional coefficient, integral coefficient, and differential coefficient respectively; is the speed error, the speed error is the time The preset working speed of the wheel minus the controller at the moment The difference between the calculated rotation speeds is is the speed error change rate.

2. The method for synchronous movement of overhead wheels based on frequency converter control according to claim 1, characterized in that: In step 1, the output ends of the two motors are respectively connected to the two wheel shafts of the overhead crane of the bridge erection machine for beam dismantling, the two frequency converters are respectively electrically connected to the two motors, and the two frequency converters are both connected to the controller.

3. The synchronous travel method of overhead crane wheels based on frequency converter control according to claim 2, characterized in that: In step 2, the sensors include an encoder and a position sensor, which are used to collect the pulse number and position of the wheel and transmit them to the controller; In step 2, at the set time interval The number of pulses received by the controller from the encoder is , the encoder generates pulses, and the controller obtains the wheel speed value based on this The formula is: 。 4. The method for synchronous movement of overhead wheels based on frequency converter control according to claim 3, characterized in that: In step 2, the method for optimizing the installation position of the sensor specifically includes: The encoder in the sensor is installed at the end of the wheel axle. The encoder is mounted on a stable bracket and keeps a reasonable distance from the axle, which is 1-2 cm. The position sensor in the sensor is installed on the side of the wheel, keeping a certain distance from the wheel, and the position sensor should be installed on a fixed bracket; The acceleration sensor in the sensor is installed next to the wheel axle, and the acceleration sensor is fixed on the bracket of the wheel axle; In step 2, the sensor is installed as follows: Calibration: Calibration is performed after the sensor is installed to ensure that the zero offset and sensitivity of the sensor meet the requirements. The calibration process includes static calibration and dynamic calibration. Static calibration is used to correct the zero offset, and dynamic calibration is used to correct the accuracy of the sensor under dynamic conditions. Protection: Install a protective cover at the sensor installation location.

5. The method for synchronous movement of overhead wheels based on frequency converter control according to claim 4, characterized in that: In step 2, static calibration includes: calibrating the sensor to obtain the zero offset of the sensor as Unit, then add bias correction when processing the data collected by the sensor, the corrected data for: ,in This is the data before sensor calibration; Dynamic correction: Use the Kalman filter to combine the data collected by the statically corrected sensor and the model of the control system to perform dynamic error correction.

6. The method for synchronous movement of overhead wheels based on frequency converter control according to claim 5, characterized in that: In step 4, adopting a high-speed data transmission method includes: adopting optical fiber communication or wireless high-speed communication between the sensor and the controller.

7. The method for synchronous movement of overhead wheels based on frequency converter control according to claim 6, characterized in that: The method for synchronous movement of overhead wheels based on frequency converter control also includes: Encoder fault detection: The encoder fault detection module is integrated into the controller to monitor the working status of the encoder in real time. When an encoder fault is detected, the fault protection mechanism is triggered in real time to stop the motor and issue a warning signal; Inverter fault detection: The inverter fault detection module is integrated into the controller to monitor the working status of the inverter in real time. When an inverter fault is detected, the fault protection mechanism is triggered in real time to stop the motor and issue a warning signal; Fault protection mechanism: When an encoder or inverter fault is detected, the controller automatically switches to safe mode, stops the motor or inverter, and notifies maintenance personnel through an alarm signal.

8. The method for synchronous movement of overhead wheels based on frequency converter control according to claim 7, characterized in that: Integrate the encoder fault detection module in the controller to monitor the encoder's working status in real time. The specific steps include: Data consistency check: By comparing the encoder data, detect the inconsistency between the data to determine whether the encoder is faulty; Signal strength check: Monitors the strength of the encoder signal. If the signal strength is lower than the set threshold, the encoder may be damaged or poorly connected.

9. The method for synchronous movement of overhead wheels based on frequency converter control according to claim 8, characterized in that: Integrate the inverter fault detection module in the controller to monitor the inverter's working status in real time. The specific steps include: Current detection: By monitoring the current output by the inverter, it is determined whether the inverter is in normal working condition. If abnormal current fluctuations are detected, it is determined that the inverter is faulty. Temperature monitoring: monitor the temperature of the inverter. If the temperature exceeds the preset safety range, it indicates that the inverter is overheating. Communication check: By checking the communication status between the inverter and the controller, it is determined whether the inverter is working normally. If the communication is interrupted or the data packet is lost, it indicates that the inverter is faulty. The fault protection mechanisms are: When an encoder or inverter fault is detected, the controller automatically switches to safe mode, stops the motor to prevent further damage to the equipment, and notifies maintenance personnel through an alarm signal. The specific steps include: Stop the motor in real time: When the encoder or inverter fault detection module is triggered, the controller sends a stop signal in real time to stop the motor; Issue warning signal: Through the sound and light alarm or other warning devices connected to the controller, notify the maintenance personnel that the controller has failed and needs to be inspected and repaired; Record fault information: The controller automatically records the time, type and data before the fault for subsequent analysis and diagnosis; Entering safe mode: Before troubleshooting, the controller enters safe mode and prohibits the overhead crane from continuing to operate to ensure safety.

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