A full-time anti-sway control method for overhead crane system based on inverter architecture

Abstract

The present invention provides a full-time anti-sway control method for a bridge crane system based on a frequency converter architecture, comprising the following steps: receiving a specified high frequency and a frequency change time; calculating a time setting range based on multiple system parameters of the bridge crane system and rope length information; selecting a time setting value within the time setting range; dividing the frequency change time into a plurality of time intervals based on the time setting value; adjusting an operating frequency command within the plurality of time intervals to change within a range between a low frequency and the specified high frequency to generate a frequency change curve; feeding back the frequency change curve and the rope length information to calculate a frequency correction value; and superimposing the frequency change curve and the frequency correction value to generate an anti-sway frequency command to drive at least one motor.

Description

Technical Field

[0001] The present invention relates to a full-time anti-sway control method for a bridge type overhead crane system, and in particular to a full-time anti-sway control method for a bridge type overhead crane system based on a frequency converter architecture. Background Art

[0002] Overhead cranes are widely used in industrial assembly and transportation applications. A typical overhead crane structure consists of a long-travel trolley, a short-travel trolley, and a vertically movable hoist (in the Z direction). The trolley and hoist operate to move suspended objects to designated locations. However, during operation, the suspended objects can experience a certain degree of swaying due to the varying speeds of the trolley, impacting work efficiency and increasing safety concerns.

[0003] The anti-sway function for cranes is suitable for indoor overhead crane installations and is used on the inverters of long-travel (X-direction) trolleys and short-travel (Y-direction) trolleys. When the main hoist is carrying a heavy load and traveling in the X or Y direction, enabling this function eliminates unnecessary sway during travel, reducing hazards, increasing production capacity, and achieving better crane control. For the same number of operations, the operating time exhibits a Gaussian distribution.

[0004] Many references have proposed related anti-sway technologies. Due to cost considerations, most of them use a sway angle estimator architecture instead of an image recognizer or (sway) angle sensor. The anti-sway controller adopts a state feedback design. However, the design of the estimator and state controller requires the setting of a large number of system parameters. In practical applications, these system parameters are difficult to measure and obtain, which adds to the complexity of use.

[0005] In angle estimation, in addition to setting system parameters, it is also necessary to infer the speed of the large and small vehicles based on the motor speed. Therefore, the use of motor position sensors is essential. However, for low-cost system configurations, the motors may not have encoders or Hall sensors installed. Even if additional sensors are installed, they will increase the cost of mechanical design and hardware configuration, and also increase implementation difficulties.

[0006] To solve the above technical difficulties, the present invention proposes a full-time anti-sway control method for a bridge crane system based on a frequency converter architecture that is simple, easy to implement, does not require a motor position sensor, and meets low-cost hardware configuration.

[0007] Therefore, how to design a simple, easy-to-implement, full-time anti-sway control method for a bridge crane system based on a frequency converter architecture that does not require a motor position sensor and meets low-cost hardware configuration is an important topic studied by the inventors of this case. Summary of the Invention

[0008] The object of the present invention is to provide a full-time anti-sway control method for a bridge crane system based on a frequency converter architecture, so as to solve the problems of the prior art.

[0009] To achieve the aforementioned objectives, the present invention proposes a full-time anti-sway control method for an overhead crane system based on a frequency converter architecture. The overhead crane system includes a frequency converter for executing the control method and at least one motor controlled by the control method. The control method comprises the steps of: receiving a specified high frequency and a frequency change time; calculating a time setting range based on multiple system parameters of the overhead crane system and rope length information; selecting a time setting value within the time setting range; dividing the frequency change time into multiple time intervals based on the time setting value; adjusting the operating frequency command within each of the multiple time intervals to vary between a low frequency and a specified high frequency to generate a frequency change curve; calculating a frequency correction value based on the frequency change curve and rope length information; and superimposing the frequency change curve and the frequency correction value to generate an anti-sway frequency command to drive the at least one motor.

[0010] To achieve the aforementioned objectives, the present invention proposes a full-time anti-sway control method for a bridge crane system based on a frequency converter architecture. The bridge crane system includes a frequency converter for executing the control method, a position sensor, and at least one motor controlled by the control method. The control method includes the following steps: receiving a specified high frequency and a frequency change time; calculating a time setting range based on multiple system parameters of the bridge crane system and rope length information; selecting a time setting value within the time setting range; dividing the frequency change time into multiple time intervals based on the time setting value; adjusting the operating frequency command within the multiple time intervals to vary between a low frequency and a specified high frequency to generate a frequency change curve; obtaining the rotation angle of at least one motor via a position sensor; estimating the swing angle of the bridge crane in a simple pendulum swing mode based on the rotation angle, and then calculating a frequency correction; and superimposing the frequency change curve and the frequency correction to generate an anti-sway frequency command to drive the at least one motor.

[0011] In order to further understand the techniques, means and effects adopted by the present invention to achieve the intended objectives, please refer to the following detailed description of the present invention and the accompanying drawings. It is believed that the objectives, features and characteristics of the present invention can be further understood in detail. However, the accompanying drawings are provided for reference and illustration only and are not intended to limit the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a structural diagram of the first embodiment of the full-time anti-sway system of the bridge type overhead crane of the present invention;

[0013] Figure 2 This is a flow chart of a first embodiment of a full-time anti-sway control method for a bridge crane system based on a frequency converter architecture;

[0014] Figure 3 for Figure 1 The architecture diagram of the anti-sway controller;

[0015] Figure 4A A block diagram of a swing angle estimation module of a first embodiment of full-time anti-sway system for a bridge crane;

[0016] Figure 4B A block diagram of a swing angle processing module of a first embodiment of full-time anti-sway system for a bridge crane;

[0017] Figure 5A A schematic diagram of the optimization of the frequency variation curve of the first embodiment of the full-time anti-sway system of the bridge crane;

[0018] Figure 5B A schematic diagram of optimizing the anti-sway frequency command of the first embodiment of full-time anti-sway for the overhead crane system;

[0019] Figure 6 The response of different damping coefficients to the swing angle and motor speed;

[0020] Figure 7 The response of different bandwidth ratios to the swing angle and motor speed;

[0021] Figure 8 This is a structural diagram of a second embodiment of the full-time anti-sway system for a bridge-type overhead crane according to the present invention;

[0022] Figure 9 Flowchart of a second embodiment of a full-time anti-sway control method for a bridge crane system based on a frequency converter architecture;

[0023] Figure 10 for Figure 8 The architecture diagram of the anti-sway controller;

[0024] Figure 11 The following is an architectural diagram of a bridge crane system including a drive mode selector;

[0025] Description of Reference Numerals

[0026] 1000: Overhead Crane System

[0027] 2000: Overhead Crane System

[0028] 100: operating device

[0029] 200, 200A: Frequency converter

[0030] 220: Anti-sway control unit

[0031] 230: Anti-sway control unit

[0032] 240: Voltage-frequency open-loop control unit

[0033] 260:Drive unit

[0034] 220a: Time frequency processing module

[0035] 220b: Swing angle estimation module

[0036] 220c: Swing angle processing module

[0037] 231: Frequency estimation module

[0038] 300: Motor

[0039] 400: Overhead crane

[0040] 500: Position sensor

[0041] f0: operation command

[0042] f1: Anti-sway frequency command

[0043] v r :Drive voltage signal

[0044] f r :Drive frequency signal

[0045] f h :Specify high frequency

[0046] T0: Frequency change time

[0047] L: Rope length information

[0048] T1: acceleration time

[0049] T2: Maintenance time

[0050] T3: deceleration time

[0051] f line :Frequency change curve

[0052] f cmp :Frequency correction

[0053] θ s :Swing angle

[0054] ω s :Swing speed

[0055] C: First control parameter

[0056] γ: Second control parameter

[0057] X1: Control variable

[0058] ω cmp :Speed correction

[0059] ζ: Damping coefficient

[0060] n:Duty cycle

[0061] Pm: Motor position signal

[0062] fdb: electrical frequency command

[0063] S11~S17: Steps

[0064] S21~S28: Steps DETAILED DESCRIPTION

[0065] The technical content and detailed description of the present invention are described below with reference to the accompanying drawings. The present invention proposes a full-time anti-sway control method for a bridge crane system. The anti-sway control method is based on a frequency converter architecture and has the following main features and functions:

[0066] Whether or not a motor position sensor is used, the anti-sway function can be achieved without a swing angle sensor, resulting in a low implementation cost. This means that neither a motor position sensor nor a swing angle sensor / image recognition unit is required, resulting in a low implementation cost.

[0067] This system only requires rope length information and has low reliance on overhead crane and motor system parameters, making it easy to implement. This means it doesn't rely heavily on system parameters such as vehicle weight, load weight, wheel diameter, and reduction ratio, making it easy to implement.

[0068] In a large vehicle architecture, if a single inverter drives two motors, simple V / F (voltage / frequency) control can also be used to achieve anti-sway. This means that V / F motor control is applicable to any single-drive-multiple-motor architecture (one inverter driving multiple motors), making it highly versatile.

[0069] The anti-sway frequency generator operates full-time, achieving anti-sway control before the crane stops, regardless of normal travel (normal acceleration and deceleration in a single direction), repeated inching (repeated acceleration and deceleration in a single direction), or repeated forward and reverse movement (repeated forward and reverse movement). This means that full-time anti-sway control is applicable to all crane operating conditions and is highly versatile.

[0070] Automated parameter design automatically adjusts control parameters based on user-preferred intensity settings, eliminating the need for trial and error. This means full-time anti-sway control is possible, providing a high degree of control freedom.

[0071] See also Figure 1 The overhead crane system 1000 includes an operating device 100, a frequency converter 200, at least one motor 300, and an overhead crane 400. In one embodiment, the overhead crane 400 includes a large vehicle body and a small vehicle body. The overhead crane system 1000 uses multiple motors to operate the different vehicle bodies of the overhead crane 400. In other embodiments, the overhead crane system 1000 uses only one motor to operate the overhead crane 400 having only a single vehicle body. Therefore, the present invention is not limited to the number of motors. Furthermore, the overhead crane 400 is typically controlled to perform a simple pendulum motion.

[0072] The user can provide the operation command f0 to the inverter 200 through the operating device 100 (for example, a remote control, a computer, etc.), and the operation command f0 includes information such as motion command, motion direction, given frequency, and acceleration / deceleration time, but the present invention is not limited thereto. Figure 1 As shown, the inverter 200 includes an anti-sway control unit 220, a voltage-frequency open-loop control unit 240, and a drive unit 260. The anti-sway control unit 220 outputs an anti-sway frequency command f1 to the voltage-frequency open-loop control unit 240 based on the operation command f0. The voltage-frequency open-loop control unit 240 performs voltage-frequency open-loop control (or V / F control) on the drive unit 260 based on the anti-sway frequency command f1, so that the drive unit 260 generates a driving voltage signal v r And the driving frequency signal f r To drive (operate) at least one motor 300. It is particularly noted that voltage-frequency open-loop control is a technique well known to those skilled in the art, and therefore its operation method will not be described in detail herein. Generally speaking, the drive unit 260 can be a drive circuit having multiple switches, a power converter, etc., but the present invention is not limited thereto.

[0073] Therefore, the focus of the present invention is how to generate the anti-sway frequency command f1 so as to optimize the voltage-frequency open-loop control and reduce the sway phenomenon when the overhead crane moves. Figure 1 、 Figure 2 、 Figure 3 、 Figure 4A 、 Figure 4B 、 Figure 5A and Figure 5B , to illustrate the control method of the first embodiment of the present invention.

[0074] At Figure 2 In step S11, the time frequency processing module 220a (eg, Figure 3 ) receives an operation command f0 from the operating device 100, wherein the operation command f0 includes a specified high frequency fh and frequency change time T0 (such as Figure 5A ), but the present invention is not limited thereto.

[0075] At Figure 2 In step S12, the time-frequency processing module 220a calculates a time setting range based on the multiple system parameters of the overhead crane system 1000 and the rope length information L. In this embodiment, the multiple system parameters of the overhead crane system 1000 include the system inertia of the overhead crane system 1000, the rated speed, and the rated torque of the motor 300. It is important to note that the multiple system parameters of the overhead crane system 1000 and the rope length information L are all pre-programmed values in the inverter 200. In this embodiment, the present invention allows users to set the acceleration and deceleration times of the overhead crane system 1000. This allows users to flexibly design the acceleration and deceleration times of the overhead crane system 1000 while considering the inverter's overcurrent limit and the anti-sway control acceptance time. However, the acceleration and deceleration times of the overhead crane system 1000 must be designed within a reasonable time setting range. The following describes how to obtain the time setting range in step S12.

[0076] The time frequency processing module 220a calculates the lower limit of the time setting range according to the system parameters of the overhead crane system 1000. Please refer to the following equation (1):

[0077]

[0078] In equation (1), t acc / dec :Time setting range, ω rate : Rated speed, T rate : Rated torque, J sys : System inertia. Next, the time-frequency processing module 220a calculates the natural swing period of the simple pendulum motion based on the rope length information L of the overhead crane 400. Please refer to the following equation (2):

[0079]

[0080] In equation (2), T swing : natural swing period, g: gravitational acceleration, L: rope length information. Next, the time frequency processing module 220a calculates the upper limit of the time setting range based on the natural swing period. Please refer to the following equation (3):

[0081]

[0082] In equation (3), t acc / dec : Time setting range, T swing: Natural swing period. Combining equations (1), (2), and (3), we can deduce the reasonable time setting range.

[0083] At Figure 2 In step S13, the user can select an appropriate time setting value within the time setting range through the time frequency processing module 220a, and use the selected time setting value as the acceleration and deceleration time of the overhead crane system 1000. Figure 5A , the selected time setting value can be used as the acceleration time T1 and the deceleration time T3. In a preferred embodiment, the acceleration time T1 and the deceleration time T3 are the same, but the present invention is not limited thereto.

[0084] At Figure 2 In step S14, the time-frequency processing module 220a divides the frequency change time T0 into a plurality of time intervals (eg, Figure 5A As shown), the multiple time intervals include acceleration time T1, maintenance time T2 and deceleration time T3. In one embodiment, as shown Figure 5A As shown, the selected time setting value can be used as the acceleration time T1 (i.e., acceleration time) and the deceleration time T3 (i.e., deceleration time), and the acceleration time T1 and the deceleration time T3 are the same. Therefore, the holding time T2 can be inferred from the known frequency change time T0, the acceleration time T1, and the deceleration time T3. In other words, based on the frequency change time T0 and the time setting value, the holding time T2 can be obtained for multiple time intervals, where the holding time T2 is between the acceleration time T1 and the deceleration time T3. It is particularly important to note that the present invention primarily allows the user to select a time setting value within the time setting range to set the acceleration time T1 and the deceleration time T3. However, the user cannot control the start or stop time of the overhead crane system 1000.

[0085] At Figure 2 In step S15, the time frequency processing module 220a adjusts the operating frequency command between the low frequency (eg, 0 Hz) and the specified high frequency f in a plurality of time intervals (T1-T3). h The frequency variation curve f is generated by changing the range of line (like Figure 5A ). The operating frequency command is a signal generated in advance in the time-frequency processing module 220a, or a signal preset in the time-frequency processing module 220a.

[0086] In one embodiment, if Figure 5A As shown, during the acceleration time T1, the frequency change curve f line Increase linearly from low frequency to specified high frequency f h During the holding time T2, the frequency change curve fline Maintain at the specified high frequency f h (In fact, the frequency variation curve f line At the specified high frequency f h During the deceleration time T3, the frequency change curve f line By specifying the high frequency f h Linearly decreases to a low frequency. However, the present invention is not limited thereto. That is, the frequency change curve f line It increases linearly from a low frequency (for example: 0Hz) to a specified high frequency f h , and in the frequency change curve f line After maintaining the specified high frequency for a period of time (for example, maintaining time T2), the frequency change curve f line The system is determined by specifying a high frequency f h Decreases linearly to low frequencies.

[0087] like Figure 3 As shown, the anti-sway control unit 220 includes a swing angle estimation module 220b and a swing angle processing module 220c. Figure 2 and Figure 3 In step S16, the swing angle estimation module 220b and the swing angle processing module 220c are based on the frequency change curve f line and the preset rope length information L to calculate the frequency correction f cmp The frequency correction value f will be described in detail below. cmp Calculation method:

[0088] Please also see Figure 2 Step S16, Figure 3 and Figure 4A The swing angle estimation module 220b first receives the frequency change curve f output by the time frequency processing module 220a. line The swing angle estimation module 220b is based on the frequency variation curve f line , calculate the frequency change of the operating frequency command within the frequency change time T0. Figure 5A The frequency on the vertical axis can represent the speed, and the acceleration (ie, the frequency variation) can be obtained by differentiating the speed once. However, the calculation method of the frequency variation of the present invention is not limited to the above method.

[0089] Next, the swing angle estimation module 220b calculates the swing angle θ of the overhead travelling crane 400 in a single pendulum swing mode based on the rope length information L and the frequency variation. s Please refer to the following equation (4):

[0090]

[0091] Among them, θ s: swing angle; s: Laplace operator; G: gravitational acceleration constant; L: rope length information; Δf: frequency change. Then, the swing angle estimation module 220b calculates the swing angle θ according to the swing angle. s , calculate the swing speed ω of the bridge crane 400 in a simple pendulum swing mode s In some embodiments, the swing angle estimation module 220b is used to estimate the swing angle θ s Differentiate to obtain the swing speed ω of the overhead crane 400 in a simple pendulum swing mode s The swing angle estimation module 220b provides the swing angle θ s and the swing speed ω s To the swing angle processing module 220c.

[0092] Please also see Figure 2 Step S15, Figure 3 and Figure 4B The swing angle processing module 220c includes a first control parameter C and a second control parameter γ. The swing angle processing module 220c first calculates the swing angle θ according to the swing angle θ. s , swing speed ω s and the first control parameter C, calculate the control variable X1. Please refer to the following equation (5):

[0093] X1=Cθ s +ω s (5)

[0094] Next, the swing angle processing module 220c multiplies the control variable X1 by the second control parameter γ to calculate the speed correction value ω cmp Please refer to the following equation (6):

[0095] ω cmp =γ×X1 (6)

[0096] The swing angle processing module 220c calculates the speed correction value ω cmp Then, the frequency correction value f is calculated according to equation (7) (as shown below): cmp Please refer to the following equation (7):

[0097]

[0098] The following will further introduce an embodiment of the present invention for designing the first control parameter C and the second control parameter γ. Generally speaking, the overhead crane system 1000 can be simplified into a second-order control system, as shown in equation (8):

[0099]

[0100] Where, L: rope length information; θ s : swing angle; f *: frequency command; ζ: damping coefficient; ω n : bandwidth. Where, f in equation (8) * That is Figure 5A Frequency variation curve f line Then, by converting Equation (8) into a standard second-order form, Equations (9) and (10) can be derived as follows:

[0101]

[0102] After sorting out equations (9) and (10), the first control parameter C and the second control parameter γ can be inferred as shown in the following equations (11) and (12):

[0103]

[0104] Therefore, according to equations (11) and (12), the damping coefficient ζ and bandwidth ω can be designed to be different. n To obtain the first control parameter C and the second control parameter γ. In a preferred embodiment, the damping coefficient ζ is in the range of 0.1 to 1 (ζ∈(0.1,1)). Bandwidth ω n As shown in the following equation (13):

[0105]

[0106] Among them, ω swing : The oscillation frequency of the overhead crane 400; n: Duty cycle. swing It is derived from the natural swing period of the overhead travelling crane 400 (such as equation (2)).

[0107] In this invention, the damping coefficient ζ and bandwidth ratio n are designed to be adjustable by the user to meet their system control needs. By designing different damping coefficients ζ, the user's desired anti-sway system stiffness can be adjusted, while adjusting the bandwidth ratio n can adjust the response speed (strength).

[0108] like Figure 6 As shown in , it is the response of different damping coefficients to the swing angle and motor speed. Figure 6It can be seen that when the damping coefficient ζ is smaller, the degree of swing angle suppression is less, and the maximum motor speed overshoot is greater. Conversely, when the damping coefficient ζ is larger, the degree of swing angle suppression is greater, and the maximum motor speed overshoot is smaller. Therefore, when the motor decelerates, the larger the damping coefficient ζ, the less likely it is to reverse. Typically, the damping coefficient ζ is set to a relatively moderate value (ζ = 0.707) at the factory. However, the design of the damping coefficient ζ can be adjusted according to user operating habits and preferences. The effect of the damping coefficient ζ can be compared to the effect of the shock absorber on a vehicle. Therefore, a smaller damping coefficient ζ will result in more noticeable shaking.

[0109] like Figure 7 As shown in , it is the response of different bandwidth ratios to the swing angle and motor speed. Figure 7 It can be seen that as the bandwidth ratio n increases, the anti-sway time (i.e., the time from the start of deceleration to the speed reaching a steady state) is relatively short. Conversely, as the bandwidth ratio n decreases, the anti-sway time is relatively long. Under reasonable swing angle principles, a larger bandwidth ratio n results in faster swing angle compensation (to zero) (faster return to steady state), but of course, the degree of swing will be more severe.

[0110] Therefore, after combining equations (2), (11), (12) and (13), the design method of the first control parameter C and the second control parameter γ has the following steps: According to the natural swing period T swing and bandwidth ratio n, calculate the response frequency (or bandwidth ω n ); According to the response frequency (or bandwidth ω n ), damping coefficient ζ and rope length information L, calculate the first control parameter C; according to the response frequency (or bandwidth ω n ) and the rope length information L, calculate the second control parameter γ. It is particularly noted that the first control parameter C and the second control parameter γ can be calculated by the user and preset in the program of the swing angle processing module 220c, but the present invention is not limited thereto.

[0111] Please also see Figure 1 、 Figure 2 Step S17, Figure 3 and Figure 5B , frequency converter 200 superimposed frequency change curve f line and the frequency correction value f generated by the swing angle processing module 220c cmp , to generate an anti-sway frequency command f1 to drive at least one motor 300. Figure 5B As shown, the frequency change curve f line and frequency correction f cmpAfter superposition, the anti-sway frequency command f1 is formed. It can be seen that the anti-sway frequency command f1 is nonlinearly increased from a low frequency (for example: 0Hz) to a specified high frequency f h , and after the anti-swing frequency command f1 is maintained at the specified high frequency for a period of time, the anti-swing frequency command f1 is changed from the specified high frequency f h Non-linearly down to low frequencies.

[0112] See also Figure 8 The overhead crane system 2000 includes an operating device 100, a frequency converter 200A, at least one motor 300, an overhead crane 400, and a position sensor 500. The frequency converter 200A includes an anti-sway control unit 230, a voltage-frequency open-loop control unit 240, and a drive unit 260. Figure 10 The anti-sway control unit 230 in the inverter 200A includes a time-frequency processing module 220a, a frequency estimation module 231, a swing angle estimation module 220b, and a swing angle processing module 220c. In the second embodiment, the position sensor 500 is used to detect the motor 300 and output a motor position signal Pm to the anti-sway control unit 230. The anti-sway control unit 230 generates an anti-sway frequency command f1 based on the motor position signal Pm and sends it to the voltage-frequency open-loop control unit 240. Please also refer to the following. Figure 8 、 Figure 9 and Figure 10 , to illustrate the control method of the anti-sway control unit 230 of the second embodiment.

[0113] In the second embodiment, the time-frequency processing module 220a is used to execute steps S21 to S25 to generate a frequency variation curve f line (like Figure 5A The waveform shown in Figure 2). Where, Figure 9 The operation method of steps S21 to S25 in Figure 2 Steps S11 to S15 in the above are not described in detail.

[0114] See also Figure 9 Step S26 and Figure 10 The anti-sway control unit 230 obtains the rotation angle of the motor 300 through the motor position signal Pm output by the position sensor 500.

[0115] See also Figure 9 Step S27 and Figure 10 The anti-sway control unit 230 estimates the swing angle θ of the overhead travelling crane 400 in a single pendulum swing mode according to the rotation angle of the motor 300. s and swing speed ω s , and then calculate the frequency correction f cmpIn this embodiment, the frequency estimation module 231 differentiates the rotation angle of the motor 300 to obtain the rotation speed of the motor 300 and uses the rotation speed of the motor 300 as the electrical frequency command fdb. The frequency estimation module 231 outputs the electrical frequency command fdb to the swing angle estimation module 220b.

[0116] Next, the swing angle estimation module 220b performs a differentiation on the electrical frequency command fdb to obtain the frequency variation (ie, acceleration) to estimate the swing angle θ. s and swing speed ω s Among them, the swing angle θ s The estimation method of has been described in the previous paragraph, please refer to equation (4). s Differentiate and obtain the swing speed ω s The swing angle estimation module 220b outputs the swing angle θ s and swing speed ω s The swing angle processing module 220c calculates the frequency correction value f according to the above equations (5) to (13). cmp .

[0117] See also Figure 9 Step S28 and Figure 10 , inverter 200A superimposed frequency change curve f line and the frequency correction value f generated by the swing angle processing module 220c cmp , to generate an anti-sway frequency command f1 to drive at least one motor 300. The waveform of the anti-sway frequency command f1 is as follows: Figure 5B shown.

[0118] The anti-sway control architecture of the present invention can also select a power unit configuration bridge crane architecture suitable for a motor (motor) with (or without) a position sensor through the drive mode switch 235, and switch the drive mode according to the actual hardware configuration to provide flexibility in use, such as Figure 11 shown.

[0119] In summary, the anti-sway control architecture proposed in the present invention can be used in overhead crane systems that are not equipped with motor position sensors (e.g., incremental encoders, absolute encoders, or Hall sensors) and swing angle sensors (e.g., angle sensors, gyroscopes, inclinometers, and image recognition devices). Furthermore, the anti-sway control architecture proposed in the present invention does not require numerous other overhead crane system parameters (e.g., the equivalent linear radius of rotation and the number of motor rotor pairs). The present invention requires only a low-cost power unit configuration and a V / F (voltage / frequency) drive mode linear motion anti-sway control architecture. It can perform full-time anti-sway during operation, even when executing point (inch) motion commands. Whether using V / F control or vector control (FOC) requiring rotor information, the control method of the present invention can achieve full-time anti-sway performance. Under V / F control, the present invention uses the motor input frequency as the input source for the swing angle estimation module 220b (or swing angle estimator), ensuring stability of the anti-sway control unit and eliminating the need for additional filter design.

[0120] The swing angle estimation module 220b of the present invention can estimate the swing angle of the hanging object or hook without the weight of the trolley, the cart and the hanging object, nor the gear ratio of the reduction gear and the diameter of the wheels of the trolley and the cart.

[0121] The above description is merely a detailed description and accompanying drawings of preferred embodiments of the present invention. However, the features of the present invention are not limited thereto and are not intended to limit the present invention. The full scope of the present invention shall be subject to the following claims. All embodiments that conform to the spirit of the claims of the present invention and similar variations thereof shall be included in the scope of the present invention. Any changes or modifications that can be easily conceived by any person skilled in the art within the scope of the present invention shall be covered by the patent scope of the following case.

Claims

1. A method for controlling full-time anti-sway of a bridge crane system based on a frequency converter architecture, wherein the bridge crane system comprises a frequency converter for executing the control method and at least one motor controlled by the control method, wherein the control method comprises the following steps: Receive the specified high frequency and frequency change time; Calculating a time setting range based on multiple system parameters of the overhead crane system and rope length information, wherein the multiple system parameters include system inertia, rated speed, and rated torque of the motor; Select a time setting value within the time setting range; Dividing the frequency change time into a plurality of time intervals according to the time setting value; Adjusting the operating frequency command within the plurality of time intervals to vary within a range of a low frequency and the specified high frequency to generate a frequency variation curve; Calculating a frequency correction amount according to the frequency variation curve and the rope length information; and superimposing the frequency variation curve and the frequency correction value to generate an anti-sway frequency command to drive the at least one motor; Also includes: According to the system parameters of the overhead crane system, a lower limit of the time setting range is calculated. The calculation formula of the lower limit is: Among them, t acc / dec :Time setting range, ω rate : Rated speed, T rate : Rated torque, J sys : system inertia; Calculate the natural swing period of the overhead crane in a simple pendulum swing mode based on the rope length information of the overhead crane system, and According to the natural swing period, the upper limit of the time setting range is calculated. The calculation formula of the upper limit is: Among them, t acc / dec : Time setting range, T swing : natural swing cycle; Also includes: Calculating a frequency change of the operating frequency command within the frequency change time according to the frequency change curve; According to the rope length information and the frequency change, the swing angle of the bridge crane in a single pendulum swing mode is calculated. The calculation formula of the swing angle is: Among them, θ s : swing angle; s: Laplace operator; G: gravitational acceleration constant; L: rope length information; Δf: frequency change; and Calculating the swing speed of the overhead travelling crane in a single pendulum swing mode according to the swing angle; Also includes: Calculating the response frequency based on the natural sway period and the bandwidth ratio; Calculating a first control parameter according to the response frequency, the damping coefficient, and the rope length information; According to the response frequency and the rope length information, a second control parameter is calculated. The first control parameter and the second control parameter are calculated as follows: Where C: first control parameter; γ: second control parameter; L: rope length information; ω n : bandwidth; ζ: damping coefficient; According to the swing angle, the swing speed and the first control parameter, the control variable is calculated. The calculation formula of the control variable is: X1 = Cθ s +ω s ; The control variable is multiplied by the second control parameter to obtain the speed correction value. The speed correction value is calculated as follows: cmp =γ×X1; and The frequency correction value is obtained according to the speed correction value. The calculation formula of the frequency correction value is:

2. The full-time anti-sway control method for a bridge crane system based on a frequency converter architecture according to claim 1 further comprises: Using the time setting values as the acceleration time and deceleration time of the multiple time intervals; and The maintaining time of the plurality of time intervals is obtained according to the frequency changing time and the time setting value, wherein the maintaining time is between the acceleration time and the deceleration time.

3. The full-time anti-sway control method for a bridge crane system based on a frequency converter architecture according to claim 2, wherein the frequency change curve linearly increases from the low frequency to the specified high frequency, and after the frequency change curve is maintained at the specified high frequency for the maintenance time, the frequency change curve linearly decreases from the specified high frequency to the low frequency.

4. The full-time anti-sway control method for a bridge crane system based on a frequency converter architecture according to claim 1, wherein the anti-sway frequency command is nonlinearly increased from the low frequency to the specified high frequency, and after the anti-sway frequency command is maintained at the specified high frequency, the anti-sway frequency command is nonlinearly decreased from the specified high frequency to the low frequency.

5. A method for controlling full-time anti-sway of a bridge crane system based on a frequency converter architecture, the bridge crane system comprising a frequency converter for executing the control method, a position sensor, and at least one motor controlled by the control method, the control method comprising the steps of: Receive the specified high frequency and frequency change time; Calculating a time setting range based on multiple system parameters of the overhead crane system and rope length information, wherein the multiple system parameters include system inertia, rated speed, and rated torque of the motor; Select a time setting value within the time setting range; Dividing the frequency change time into a plurality of time intervals according to the time setting value; Adjusting the operating frequency command within the plurality of time intervals to vary within a range of a low frequency and the specified high frequency to generate a frequency variation curve; obtaining a rotation angle of the at least one motor through the position sensor; estimating the swing angle and swing speed of the overhead travelling crane in a single pendulum swing mode according to the rotation angle, and then calculating the frequency correction amount; as well as superimposing the frequency variation curve and the frequency correction value to generate an anti-sway frequency command to drive the at least one motor; Also includes: The lower limit of the time setting range is calculated based on the system parameters of the overhead crane system. The calculation formula of the lower limit is: Among them, t acc / dec :Time setting range, ω rate : Rated speed, T rate : Rated torque, J sys : system inertia; Calculating the natural swing period of the simple pendulum motion based on the rope length information of the bridge crane system, and According to the natural swing period, the upper limit of the time setting range is calculated. The calculation formula of the upper limit is: Among them, t acc / dec : Time setting range, T swing : natural swing cycle; Also includes: Calculating a frequency change of the operating frequency command within the frequency change time according to the frequency change curve; According to the rope length information and the frequency change, the swing angle of the overhead crane in a single pendulum swing mode is calculated. The calculation formula of the swing angle is: Among them, θ s : swing angle; s: Laplace operator; G: gravitational acceleration constant; L: rope length information; Δf: frequency change; and Calculating the swing speed of the overhead travelling crane in a single pendulum swing mode according to the swing angle; Also includes: Calculating the response frequency based on the natural sway period and the bandwidth ratio; Calculating a first control parameter according to the response frequency, the damping coefficient, and the rope length information; According to the response frequency and the rope length information, a second control parameter is calculated. The first control parameter and the second control parameter are calculated as follows: Where C: first control parameter; γ: second control parameter; L: rope length information; ω n : bandwidth; ζ: damping coefficient; According to the swing angle, the swing speed and the first control parameter, the control variable is calculated. The calculation formula of the control variable is: X1 = Cθ s +ω s ; The control variable is multiplied by the second control parameter to obtain the speed correction value. The speed correction value is calculated as follows: cmp =γ×X1; and The frequency correction value is obtained according to the speed correction value. The calculation formula of the frequency correction value is:

6. The full-time anti-sway control method for a bridge crane system based on a frequency converter architecture according to claim 5 further comprises: Using the time setting values as the acceleration time and deceleration time of the multiple time intervals; and The maintaining time of the plurality of time intervals is obtained according to the frequency changing time and the time setting value, wherein the maintaining time is between the acceleration time and the deceleration time.

7. The full-time anti-sway control method for a bridge crane system based on a frequency converter architecture according to claim 6, wherein the frequency change curve linearly increases from the low frequency to the specified high frequency, and after the frequency change curve is maintained at the specified high frequency for the maintenance time, the frequency change curve linearly decreases from the specified high frequency to the low frequency.

8. The full-time anti-sway control method for a bridge crane system based on a frequency converter architecture according to claim 5, wherein the anti-sway frequency command is nonlinearly increased from the low frequency to the specified high frequency, and after the anti-sway frequency command is maintained at the specified high frequency, the anti-sway frequency command is nonlinearly decreased from the specified high frequency to the low frequency.

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