A hoist lifting control method and system based on a permanent magnet synchronous motor

Abstract

The application discloses a hoisting and lifting control method and system based on a permanent magnet synchronous motor, and belongs to the technical field of hoisting and lifting control. The application sets a hoisting and lifting model composed of a feedforward ring, a gravity ring, a damping ring and a disturbance ring, can adjust the loop combination in the hoisting and lifting model according to specific working conditions such as load lifting, hovering and releasing, and updates key parameters and variables of the model through real-time collection of working parameters of the crane, thereby improving the accuracy and stability of hoisting and lifting control. Further, the application calculates the driving error of the motor by collecting the starting angle and the braking angle of the motor, corrects core control parameters such as the motor torque constant based on the driving error, and can further improve the control accuracy and running stability of the crane in the load lifting process.

Description

Technical Field

[0001] This invention relates to the field of lifting and hoisting control technology, and in particular to a lifting and hoisting control method and system based on a permanent magnet synchronous motor. Background Technology

[0002] During crane operation, especially during motor startup, braking, high-speed trolley movement, or sudden load changes, the hoisted cargo inevitably experiences vertical and horizontal swaying and vibration. This not only affects positioning accuracy and operational efficiency but also poses safety hazards. Chinese Patent Publication No. CN113325715A discloses a global continuous sliding mode control method for bridge cranes based on feedforward control, which estimates and compensates for system disturbances through a disturbance observer. This method assumes that the weight of the cargo and the disturbance are known or predictable, and only involves a sliding surface during the sliding phase, making it difficult to simultaneously handle complex dynamic problems involving multiple degrees of freedom coupling. Existing technologies typically handle anti-sway and positioning separately, which can easily lead to poor motor response, overshoot, or oscillation during operating condition switching. Therefore, it is necessary to propose a lifting control method that can comprehensively consider wire rope sway, load horizontal vibration, and positioning accuracy, and can adjust the control strategy according to real-time operating conditions to achieve smooth, accurate, efficient, and safe crane operation. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a crane lifting control method and system based on a permanent magnet synchronous motor. This invention adjusts the motor's output current according to the real-time operating conditions of the crane by tuning the crane lifting model, and updates the crane lifting model in conjunction with the wire rope, load, and motor operating parameters to improve the stability of the crane during operation.

[0004] The objective of this invention can be achieved through the following technical means:

[0005] A hoisting control method based on a permanent magnet synchronous motor includes the following steps:

[0006] Step 1: Adjust the lifting and hoisting model. The lifting and hoisting model includes at least a feedforward loop, a gravity loop, a damping loop, and a disturbance loop. After receiving the start signal, identify the rotor's start angle.

[0007] Step 2: Execute the angular acceleration curve of the feedforward loop, calculate the target torque of the motor based on the lifting and hoisting model with the disturbance loop disabled, calculate the target current based on the target torque and torque constant, and provide the target current to the motor;

[0008] Step 3: Collect the operating parameters of the motor, load and wire rope, update the feedforward loop, gravity loop and damping loop. If the angular acceleration curve has been completed, proceed to step 4; otherwise, return to step 2.

[0009] Step 4: If a start signal is received, calculate the target torque and target current of the motor based on the lifting and hoisting model with the feedforward loop and damping loop disabled, provide the target current to the motor, collect the instantaneous current of the motor to update the gravity loop, and proceed to step 5; otherwise, proceed to step 6.

[0010] Step 5: If a stop signal is received, the motor brakes, the rotor braking angle is identified, the drive error is calculated based on the starting angle and braking angle, the torque constant is updated, and the process returns to step 2; otherwise, proceed to step 6.

[0011] Step 6: Restart the motor, calculate the target torque and target current of the motor based on the lifting model with the feedforward loop and disturbance loop disabled, provide the target current to the motor, collect the operating parameters of the motor, load and wire rope, update the gravity loop and damping loop, recalculate the target current until the target current is less than the starting lower limit, and return to Step 1.

[0012] In this invention, in step 1, the feedforward loop outputs inertial compensation torque based on the feedforward angular acceleration of the rotor and the moment of inertia of the load; the gravity loop outputs gravity compensation torque based on the angular velocity of the rotor and the load torque; the damping loop outputs damping compensation torque based on the swing angle change rate of the wire rope and the vibration velocity of the load; and the disturbance loop outputs oscillation compensation torque based on the feedforward acceleration of the trolley and the length of the wire rope.

[0013] In this invention, in step 2, the angular acceleration curve includes an ascending curve and a descending curve. The feedforward angular acceleration of the rotor is extracted from the angular acceleration curve. The target torque is calculated by combining the feedforward loop, gravity loop and damping loop. The target current is calculated by combining the target torque and torque constant.

[0014] In this invention, in step 3, the operating parameters of the motor include the instantaneous current of the motor and the instantaneous angle of the rotor; the operating parameters of the load include the load vibration speed and the load torque; and the operating parameters of the wire rope include the swing angle and length of the wire rope.

[0015] In this invention, the instantaneous torque is calculated based on the instantaneous current of the motor, the torque error is calculated based on the instantaneous torque and the target torque, the load torque is updated based on the torque error, and then the gravity ring is updated.

[0016] In this invention, the theoretical angle is calculated based on the starting angle and the rotor angular velocity, the angle error is calculated based on the instantaneous angle and the theoretical angle, the feedforward angular acceleration of the rotor is updated based on the angle error, and then the feedforward loop is updated.

[0017] In this invention, the swing angle change rate of the wire rope is calculated based on the swing angle of the wire rope, the swing energy of the wire rope is calculated by combining the swing angle and the swing angle change rate, the swing damping coefficient is updated based on the swing energy, the vibration energy of the load is calculated based on the load vibration velocity, the vibration damping coefficient is updated based on the vibration energy, and then the damping ring is updated.

[0018] In this invention, in step 5, multiple sets of direct-axis currents of the motor are collected, the current integral is calculated based on the multiple sets of direct-axis currents, and the torque constant is updated by combining the drive error and the current integral.

[0019] A lifting control system for implementing the lifting control method based on a permanent magnet synchronous motor includes:

[0020] A permanent magnet synchronous motor is configured to drive the load;

[0021] The signal receiving unit is configured to receive external control signals;

[0022] The rotor acquisition unit is configured to identify the rotor's starting angle and braking angle;

[0023] The encoding acquisition unit is configured to identify the instantaneous angle of the rotor;

[0024] The current acquisition unit is configured to acquire the instantaneous current of the motor;

[0025] The wire rope acquisition unit is configured to acquire the swing angle of the wire rope;

[0026] The vibration acquisition unit is configured to acquire the vibration velocity of the load;

[0027] The data analysis unit is configured to generate the target torque for the motor;

[0028] The lifting control unit is configured to generate the target current for the motor;

[0029] The model update unit is configured to update the lifting and hoisting model;

[0030] The register unit is configured to store model parameters of the lifting and hoisting model.

[0031] The lifting and hoisting control method and system based on a permanent magnet synchronous motor, as described in this invention, offers the following advantages: This invention constructs a lifting and hoisting model composed of a feedforward loop, a gravity loop, a damping loop, and a disturbance loop. The loop combinations within the model can be adjusted according to specific operating conditions such as load lifting, hovering, and release. Furthermore, by real-time acquisition of the crane's operating parameters, the key parameters and variables of the model are updated, thereby improving the accuracy and stability of the lifting and hoisting control. Further, this invention calculates the motor's drive error by acquiring the motor's starting angle and braking angle, and corrects core control parameters such as the motor's torque constant based on the drive error, further improving the control accuracy and operational stability of the crane during load lifting and hoisting. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the lifting and hoisting control based on a permanent magnet synchronous motor according to the present invention.

[0033] Figure 2 This is a flowchart of the hoisting and lifting control method based on a permanent magnet synchronous motor according to the present invention;

[0034] Figure 3 This is a preferred direct-axis current curve of the present invention;

[0035] Figure 4 This is a preferred cross-axis current curve diagram according to the present invention;

[0036] Figure 5 This is a schematic diagram of the load movement in the starting and releasing states of the present invention.

[0037] Figure 6 A schematic diagram of the load motion in the ideal rising and falling states of the present invention;

[0038] Figure 7 This is a schematic diagram of the load movement in the actual rising and falling states of the present invention;

[0039] Figure 8 This is a preferred rotor feedforward angular acceleration curve of the present invention;

[0040] Figure 9 This is a preferred rotor angular velocity curve of the present invention;

[0041] Figure 10 This is a schematic diagram of the lifting and hoisting model of the present invention;

[0042] Figure 11 This is a flowchart of the load lifting process based on the lifting model of the present invention;

[0043] Figure 12 This is a block diagram of the lifting control system for implementing the lifting control method based on a permanent magnet synchronous motor according to the present invention.

[0044] The reference numerals in the attached drawings are: permanent magnet synchronous motor 100, drum 200, wire rope 210, hook 220, and load 300. Detailed Implementation

[0045] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0046] like Figure 1As shown, in a crane drive system based on a permanent magnet synchronous motor, the stator winding of the permanent magnet synchronous motor 100 generates a rotating magnetic field under the precise current command of the controller. This magnetic field drives the rotor, which is rigidly connected to it and equipped with permanent magnets, to rotate synchronously. The rotor transmits electromagnetic torque losslessly to the coaxially connected drum 200 through its centrally rigidly connected power output shaft. Multiple turns of wire rope 210 are wound on the drum 200, with one end of the wire rope 210 extending downward and connected to the hook 220. The controller controls the rotation direction, angular velocity, and output torque of the rotor by controlling the phase and amplitude of the motor input current, ultimately driving the drum 200 to retract or release the wire rope 210 wound on it, thereby raising or lowering the load 300 suspended on the hook 220, achieving smooth lifting and precise positioning of the load 300. Example 1

[0047] like Figures 1 to 11 As shown, a lifting and hoisting control method based on a permanent magnet synchronous motor according to the present invention includes the following steps.

[0048] Step 1: Set up the lifting model. The lifting model includes at least a feedforward loop, a gravity loop, a damping loop, and a disturbance loop. After receiving the start signal, identify the rotor's start angle. In the lifting model, the feedforward loop outputs inertia compensation torque based on the rotor's feedforward angular acceleration and the load's moment of inertia; the gravity loop outputs gravity compensation torque based on the rotor's angular velocity and the load torque; the damping loop outputs damping compensation torque based on the wire rope's swing angle rate of change and the load's vibration velocity; and the disturbance loop outputs oscillation compensation torque based on the trolley's feedforward acceleration and the wire rope length. Initially, set the load's moment of inertia and vibration velocity, and the wire rope's swing angle rate of change to 0, then initialize the load torque T. m,0 =MgR0 / η0. M is the equivalent mass of the load, g is the gravitational acceleration, and R0 and η0 are the core radius of the drum and the initial transmission efficiency, respectively. η0 is typically between 0.85 and 0.95. The preferred method for adjusting the lifting and hoisting model is described in Example 2.

[0049] A permanent magnet synchronous motor contains six sets of current vectors in different directions, with an electrical angle interval of 60° between each set. Pulse voltages are sequentially injected into the six sets of directions of the motor, and the four sets of directions with the smallest currents are extracted. Pulse voltages are then injected into these four sets of directions, and the corresponding four peak currents are collected to calculate the first rotor rotation angle. Next, the two sets of directions with the largest currents are extracted, and pulse voltages are injected into these two sets of directions. The corresponding two peak currents are collected, and the first rotor direction angle is calculated. The starting angle can be calculated based on the first rotation angle and the first direction angle. This invention does not limit the method for detecting the starting angle. In another embodiment, other methods such as magnetic pole orientation and high-frequency injection can also be used to obtain the starting angle.

[0050] Step 2: Execute the angular acceleration curve of the feedforward loop, calculate the target torque of the motor based on the lifting model with the disturbance loop disabled, calculate the target current based on the target torque and torque constant, and provide the target current to the motor. The angular acceleration curve includes an ascending curve and a descending curve. When the load is in an ascending state, the ascending curve of the feedforward loop is executed; when the load is in a descending state, the descending curve of the feedforward loop is executed. Figure 8 The curves show the changes in feedforward angular acceleration as the load rises, hovers, and falls. Ideally, the load should rise or fall purely vertically, such as... Figure 6 As shown. However, in actual working conditions, due to the load's own center of gravity shift and the disturbance torque from external wind forces, the load will deviate from its vertical equilibrium position when rising or falling, such as... Figure 7 As shown. It should be noted that the angular acceleration curve of the feedforward loop starts after the load is stably lifted off the ground and ends when the deceleration phase before the load touches the ground is completed during the load's descent. Figure 5 The diagram illustrates the motion of the load during start-up and release.

[0051] Based on the real-time load status, the rotor's feedforward angular acceleration and angular velocity are extracted from the angular acceleration and angular velocity curves, respectively, and then input into the feedforward loop and gravity loop, respectively. The feedforward loop then generates the inertial compensation torque T. 11 Based on the gravity ring, a gravity compensation torque T is generated. 12 The damping compensation torque T is generated based on the damping ring. 13 The target torque T1 is calculated by combining the feedforward loop, gravity loop, and damping loop, i.e., T1 = T 11 +T 12 +T 13 Based on the target torque T1 and torque constant K T Calculate the target current i q i q =T1 / K T In the control strategy of permanent magnet synchronous motors, in order to make the output torque of the motor completely controlled by the quadrature axis current, the direct axis current of the motor is usually set to 0. In this invention, the target current obtained by converting the target torque calculated by the lifting model into the torque constant is the quadrature axis current.

[0052] Step 3: Collect the operating parameters of the motor, load, and wire rope; update the feedforward loop, gravity loop, and damping loop. If the angular acceleration curve has been completed, proceed to Step 4; otherwise, return to Step 2. The motor's operating parameters include the instantaneous current and rotor's instantaneous angle. The load's operating parameters include the load vibration velocity and load torque. The wire rope's operating parameters include the wire rope's swing angle and length. In this invention, the load vibration velocity refers to the horizontal vibration velocity of the load. The wire rope's swing angle is the angle between the wire rope and the vertical line. The wire rope's swing angle and length can be measured by an inclination sensor installed on the hook and an encoder on the drum. The load's vibration velocity can be measured by an inertial measurement unit installed on the hook. The motor's instantaneous current and rotor's instantaneous angle can be measured by a current sensor and the motor's encoder.

[0053] The gravity loop is updated based on the instantaneous current of the motor, the feedforward loop is updated based on the instantaneous angle of the rotor, and the damping loop is updated based on the wire rope swing angle and load vibration velocity. Specifically, the instantaneous torque is calculated based on the instantaneous current of the motor, the torque error is calculated based on the instantaneous torque and the target torque, the load torque is updated based on the torque error, and then the updated load torque is input into the gravity loop. The theoretical angle is calculated based on the starting angle and the rotor angular velocity, the angle error is calculated based on the instantaneous angle and the theoretical angle, the correction amount of the feedforward angular acceleration is calculated based on the angle error, and the feedforward loop is updated based on the correction amount. Further, the rate of change of the wire rope swing angle is calculated based on the wire rope swing angle, the swing energy of the wire rope is calculated by combining the swing angle and the rate of change of the swing angle, and the swing damping coefficient is updated based on the swing energy. The vibration energy of the load is calculated based on the load vibration velocity, and the vibration damping coefficient is updated based on the vibration energy. Then the updated rate of change of the wire rope swing angle, the load vibration velocity, the swing damping coefficient, and the vibration damping coefficient are input into the damping loop. The specific steps for updating the gravity loop and the feedforward loop are as described in Example 3. The specific steps for updating the damping ring are described in Example 4.

[0054] Step 4: If a start-up signal is received, calculate the target torque and target current of the motor based on the lifting model with feedforward and damping loops disabled, provide the target current to the motor, collect the instantaneous current of the motor to update the gravity loop, and proceed to Step 5; otherwise, proceed to Step 6. When a start-up signal is received, the trolley begins to move horizontally on the bridge. At this time, the load is in a suspended state. Due to the influence of the trolley's acceleration, the load is prone to swaying in the horizontal direction. Collect the length of the wire rope, input the length of the wire rope and the acceleration of the trolley into the disturbance loop, and generate the sway compensation torque T. 14 Since the rotor angular velocity is 0 when the load is suspended, the gravity compensation torque T output by the gravity ring is... 12 That is, the load torque. The target torque T1 of the motor is calculated by combining the gravity loop and the disturbance loop, where T1 = T 12 +T 14The target current is calculated based on the target torque, following the steps described in step 2. After providing the target current to the motor, the instantaneous current of the motor is collected, and the gravity loop is updated based on the instantaneous current, as described in Example 3.

[0055] Step 5: If a stop signal is received, the motor brakes, the rotor's braking angle is identified, the drive error is calculated based on the starting angle and braking angle, the torque constant is updated, and the process returns to Step 2; otherwise, proceed to Step 6. Specifically, if a stop signal is received, the trolley stops moving, the motor brakes, and the load enters a descent state. The rotor's braking angle and the load's vertical displacement are collected. The actual angular displacement is calculated based on the starting angle and braking angle, and the theoretical angular displacement is calculated based on the load's vertical displacement. The drive error is calculated by combining the actual and theoretical angular displacements. Multiple sets of direct-axis currents are collected from the motor during the period from start-up to braking, and the current integral is calculated. The motor's torque constant is updated based on the drive error and the current integral, as described in Example 5. The method for identifying the braking angle is the same as that for the starting angle, as described in Step 1.

[0056] Step 6: Restart the motor. Calculate the target torque and target current of the motor based on the lifting model with the feedforward and disturbance loops disabled. Provide the target current to the motor, collect the operating parameters of the motor, load, and wire rope, update the gravity loop and damping loop, and recalculate the target current until it is less than the starting lower limit. Return to Step 1. When the load enters the release state, the load mass decreases sharply, and the impact generated by the load release can easily cause the wire rope to swing significantly. Therefore, it is necessary to calculate the target torque of the motor using both the gravity loop and damping loop. Collect the real-time angular velocity of the rotor and input the real-time angular velocity into the gravity loop to generate the gravity compensation torque T. 12 The damping ring generates a damping compensation torque T based on the load vibration velocity and the rate of change of the wire rope swing angle. 13 Then the target torque T1 = T 12 +T 13 Calculate the target current based on the target torque. After supplying the target current to the motor, update the gravity loop based on the instantaneous current of the motor, and update the damping loop based on the load vibration velocity and the wire rope swing angle. Update the target current according to the updated gravity loop and damping loop. When the target current is less than the starting lower limit, end the current lifting operation, return to step 1, and start the next lifting operation.

[0057] like Figure 11 In this invention, different loop combinations of lifting and hoisting models are used according to the real-time state of the load. When the load is rising or falling, a lifting and hoisting model with the disturbance loop disabled is used; when the load is in a hovering state, a lifting and hoisting model with the feedforward loop and damping loop disabled is used; and when the load is in a released state, a lifting and hoisting model with the feedforward loop and disturbance loop disabled is used. By implementing load lifting and hoisting control strategies under different states through different lifting and hoisting models, the accuracy and stability of crane lifting operations can be effectively improved. Example 2

[0058] like Figure 10 As shown, this embodiment further discloses a preferred method for adjusting the lifting and hoisting model. The lifting and hoisting model T1 = G1(J m ,a e )+G2(ω e ,T m )+G3(v d ,A)+G4(a c G1(J), where T1 is the target torque of the motor. m ,a e G2(ω) is the transfer function of the feedforward loop. e ,T m G3(v) is the transfer function of the gravity loop. d Let A be the transfer function of the damping ring, and G4(a) be the transfer function of the damping ring. c ,L) is the transfer function of the disturbance loop.

[0059] Specifically, the input variable of the feedforward loop is the equivalent moment of inertia J of the load. m and the rotor's feed angular acceleration a e The feedforward loop has the functional form G1(J m ,a e )=(J0+J m )a e J0 is the moment of inertia of the motor rotor. Figure 8 The curves showing the variation of the rotor's feedforward angular acceleration under different load conditions are illustrated. The output of the feedforward loop is the inertial compensation torque T of the load and rotor. 11 That is, T 11 =G1(J m ,a e )=(J0+J m )a e .

[0060] The input variable for the gravity loop is the angular velocity ω of the rotor. e and load torque T m The functional form of the gravity ring is G2(ω e ,T m )=Bω e +T m B is the coefficient of viscous friction, with units of N·m·s / rad. The rotor's angular velocity variation is referenced... Figure 9 As shown. In this invention, the load torque T is initialized before each load increase. m=MgR0 / η0. M is the equivalent mass of the load, g is the gravitational acceleration, and R0 and η0 are the core radius of the drum and the initial transmission efficiency, respectively. η0 is typically between 0.85 and 0.95. The output of the gravity ring is the gravity-compensated torque T considering dynamic friction. 12 That is, T 12 = G2(ω e ,T m )=Bω e +T m .

[0061] The input variable of the damping ring is the load vibration velocity v. d The damping ring's functional form is G3(v) = the rate of change of the swing angle of the wire rope. d A) = -k d v d -k s A. k d This is the vibration damping coefficient, with units of N·m·s / rad, k. d It will change with variations in load and vibration. k s This is the oscillation damping coefficient, with units of N·m·s / rad, k. s It will change with the swing angle of the wire rope. d and k s The update is described in Example 4. The output of the damping ring is a damping compensation torque T that takes into account load vibration and wire rope oscillation. 13 That is, T 13 =G3(v d A) = -k d v d -k s A.

[0062] The input variable of the disturbance loop is the feedforward acceleration a of the trolley. c Given the length L of the wire rope, the function form of the disturbance loop is G4(a c ,L)=MLa c The output of the disturbance loop is the oscillation compensation torque T, which takes into account the inertia of the trolley. 14 That is, T 14 =G4(a c ,L)=MLa c .

[0063] The aforementioned lifting and hoisting model is essentially a modular framework that can be flexibly combined and expanded. In this invention, a PID controller can be used to dynamically enable or disable the four loops (feedforward loop, gravity loop, damping loop, and disturbance loop) according to real-time operating conditions. In a more preferred embodiment, fuzzy inference, neural network, and other algorithms can be introduced into each loop to achieve adaptive parameter adjustment and nonlinear compensation. Furthermore, in a further embodiment, the model can be compatible with and nested with more basic control closed loops, such as current loop, speed loop, and position loop, to achieve a more refined full closed-loop control system through cascade tuning of multi-level loops. Example 3

[0064] This embodiment further discloses a preferred method for updating the gravity loop and the feedforward loop. In this invention, during the load rise and fall phases, the load torque and feedforward angular acceleration are updated according to the instantaneous current of the motor and the instantaneous angle of the rotor, respectively, to achieve real-time dynamic correction of the gravity loop and the feedforward loop.

[0065] The gravity loop is updated based on the instantaneous current of the motor. Since the instantaneous current of the motor is a three-phase current, it is necessary to use Clark and Park transformations to convert the instantaneous current (i) in the three-phase stationary coordinate system into a three-phase stationary coordinate system. a i b i c This is converted into a direct-axis current i in a coordinate system that rotates synchronously with the rotor magnetic field. d1 and cross-axis current i q1 Based on the quadrature-axis current i q1 Calculate the instantaneous torque T2, T2=i q1 K T The torque error ΔT can be obtained from the instantaneous torque T2 and the target torque T1, where ΔT = T1 - T2. The load torque T is then updated based on the torque error ΔT. m Updated load torque T m =T m +ΔTt n , t n The sampling period is [number]. Then, the updated load torque T [is used]. m Input gravity ring G2(ω) e ,T m ). Figure 3 and Figure 4 The graphs show the changes in the direct-axis current and quadrature-axis current of the motor under different conditions.

[0066] The feedforward loop is updated based on the instantaneous angle of the rotor. First, the theoretical angle θ of the rotor is calculated based on the starting angle θ1 and the angular velocity curve ω(τ). th , Where τ is the time variable, t1 and t2 are the motor starting time and the sampling time of the instantaneous current, respectively. dTo control the total delay time of computation and signal transmission. Secondly, based on the instantaneous angle θ s and theoretical angle θ th Calculate the angular error Δθ, Δθ = θ th -θ s The angle error Δθ is then input into the PID controller to obtain the correction amount Δa for the feedforward angular acceleration. Next, the effective winding radius R of the wire rope on the drum is collected. e Update the load's moment of inertia J m J m =MR e 2 Finally, the feedforward angular acceleration a is updated based on the correction Δa. e The updated feedforward angular acceleration and the moment of inertia of the load are input into the feedforward loop G1(J). m ,a e ), thus obtaining the updated feedforward loop G1(J m ,a e +Δa). Example 4

[0067] This embodiment further discloses a preferred method for updating the damping ring. Because the wire rope swing and load oscillation change frequently during load rise or fall, it is necessary to collect the wire rope swing angle and load vibration velocity in real time to adjust the relevant parameters of the damping ring to ensure the accuracy of the lifting model.

[0068] Calculate the rate of change of the wire rope's swing angle and its oscillation energy. This is based on the current swing angle α of the wire rope. t Calculate the rate of change of the swing angle of the wire rope, A, where A = (α) t -α t-1 ) / t n α t-1 t represents the swing angle of the wire rope at the previous sampling time. n The sampling period is based on the swing angle α of the wire rope. t The oscillating energy E of the wire rope is calculated using the rate of change of the oscillation angle A. s E s =1 / 2ML 2 A 2 +MgL(1-cosα t Where M is the equivalent mass of the load, L is the length of the wire rope, and g is the acceleration due to gravity.

[0069] Update the oscillation damping coefficient. Collect the oscillation frequency f of the wire rope. α Combined with the oscillation energy E s and oscillation frequency f α Update the swing damping coefficient k s The updated oscillation damping coefficient k s '=k s+p1E s +p2(f α -f n ) 2 Among them, f n The natural frequency of the wire rope. p1 is the energy gain coefficient, typically taken as 0.01 to 0.1. p2 is the frequency sensitivity coefficient, typically taken as 1 to 10. When the swing intensity of the wire rope increases, the damping can be increased by adjusting p1 and p2.

[0070] Update the vibration damping coefficient. Differentiate the load vibration velocity to obtain the vibration acceleration a. d Based on the load vibration velocity v d Calculate the vibration energy E of the load d E d =1 / 2mv d 2 Vibrational energy E based on load d Update vibration damping coefficient k d The updated vibration damping coefficient k d '=k d +q1E d +q2a d a d q1 is the vibration acceleration of the load, which can be obtained by differentiating the load vibration velocity. q2 is the energy gain coefficient, typically taken as 0.01~0.1. q3 is the acceleration sensitivity coefficient, typically taken as 0.1~1.

[0071] Finally, the updated wire rope swing angle change rate, load vibration velocity, swing damping coefficient, and vibration damping coefficient are re-inputted into the damping ring G3(v). d A) = -k d v d -k s A. Example 5

[0072] This embodiment further discloses a preferred method for updating the torque constant. In this invention, when the motor switches from a starting state to a braking state, the driving error of the motor is calculated based on the starting angle and braking angle, and the torque constant is updated based on the driving error. The specific calculation process is as follows.

[0073] Calculate the driving error. Calculate the actual angular displacement θ based on the starting angle θ1 and braking angle θ2. 12 θ 12 =θ2-θ1. The theoretical angular displacement θ0 is calculated based on the vertical displacement h of the load, where θ0 = hη / R0, η is the transmission ratio, and R0 is the drum radius. Then the driving error e... θ =θ0-θ 12 .

[0074] Calculate the current integral of the direct-axis current. Collect multiple sets of direct-axis current i during the motor's operation from startup to braking. d (t), then the current integral t1 and t3 are the motor start-up and braking times, respectively, and t is the sampling time.

[0075] Update the torque constant based on the drive error e. θ and current integral Q d Update the motor's torque constant K T The updated torque constant K T '=K T +γT m e θ / Q d Where γ is the gain coefficient, typically set to a positive number much smaller than 1, such as 0.05 or 0.1. The gain coefficient allows for smoother adjustment of the torque constant, preventing control loop instability caused by sudden parameter changes, which could lead to load jitter or oscillation. m This represents the load torque. Example 6

[0076] like Figure 12 As shown, a lifting control system for implementing the lifting control method based on a permanent magnet synchronous motor includes a permanent magnet synchronous motor, a signal receiving unit, a rotor acquisition unit, a current acquisition unit, an encoding acquisition unit, a wire rope acquisition unit, a vibration acquisition unit, a data analysis unit, a lifting control unit, a model update unit, and a register unit.

[0077] The permanent magnet synchronous motor is configured to drive the load. The permanent magnet synchronous motor has a three-phase circuit, such as... Figure 12 As shown, when the motor is in the starting state, energy flows from the power supply to the motor through the inverter; when the motor is in the regenerative braking state, energy is fed back from the motor to the DC bus through the inverter, and may be further fed back to the grid.

[0078] The signal receiving unit is configured to receive external control signals and transmit them to the lifting control unit. The external control signals include start signals, start signals, stop signals, release signals, etc.

[0079] The rotor acquisition unit is configured to identify the rotor's starting and braking angles. The encoder acquisition unit is configured to identify the rotor's instantaneous angles, measured by an encoder mounted on the permanent magnet synchronous motor. Additionally, the encoder acquisition unit can also measure the length of the wire rope using an encoder on the drum. The current acquisition unit is configured to acquire the motor's instantaneous current, measuring the instantaneous current of the motor's three phases using a current sensor.

[0080] The wire rope acquisition unit is configured to acquire the swing angle of the wire rope, which is measured by an inclination sensor mounted on the hook. The vibration acquisition unit is configured to acquire the vibration velocity of the load, which is measured by an inertial measurement unit mounted on the hook.

[0081] The data analysis unit is configured to generate the target torque of the motor. The data analysis unit calculates the target torque based on the lifting and hoisting model, updates the gravity loop based on the instantaneous current of the motor, updates the feedforward loop based on the instantaneous angle of the rotor, updates the damping loop based on the wire rope swing angle and load vibration velocity, and updates the disturbance loop based on the trolley acceleration and wire rope length.

[0082] The lifting control unit is configured to generate the target current for the motor. Based on the target torque and torque constant, the lifting control unit calculates the target current, generates a corresponding current command based on the target current, and controls the motor to output the corresponding current to drive the rotor to rotate, thereby controlling the load to rise, fall, or remain stable.

[0083] The model update unit is configured to update the lifting and hoisting model. The model update unit adjusts the loop combinations in the lifting and hoisting model according to the load conditions. The register unit is configured to store the model parameters of the lifting and hoisting model.

[0084] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A hoisting control method based on a permanent magnet synchronous motor, characterized in that, Includes the following steps: Step 1: Adjust the lifting and hoisting model. The lifting and hoisting model includes at least a feedforward loop, a gravity loop, a damping loop, and a disturbance loop. After receiving the start signal, identify the rotor's start angle. Step 2: Execute the angular acceleration curve of the feedforward loop, calculate the target torque of the motor based on the lifting and hoisting model with the disturbance loop disabled, calculate the target current based on the target torque and torque constant, and provide the target current to the motor; Step 3: Collect the operating parameters of the motor, load and wire rope, update the feedforward loop, gravity loop and damping loop. If the angular acceleration curve has been completed, proceed to step 4; otherwise, return to step 2. Step 4: If a start signal is received, calculate the target torque and target current of the motor based on the lifting and hoisting model with the feedforward loop and damping loop disabled, provide the target current to the motor, collect the instantaneous current of the motor to update the gravity loop, and proceed to step 5; otherwise, proceed to step 6. Step 5: If a stop signal is received, the motor brakes, the rotor braking angle is identified, the drive error is calculated based on the starting angle and braking angle, the torque constant is updated, and the process returns to step 2; otherwise, proceed to step 6. Step 6: Restart the motor, calculate the target torque and target current of the motor based on the lifting model with the feedforward loop and disturbance loop disabled, provide the target current to the motor, collect the operating parameters of the motor, load and wire rope, update the gravity loop and damping loop, recalculate the target current until the target current is less than the starting lower limit, and return to Step 1.

2. The lifting and hoisting control method based on a permanent magnet synchronous motor according to claim 1, characterized in that, In step 1, the feedforward loop outputs inertial compensation torque based on the rotor's feedforward angular acceleration and the load's moment of inertia; the gravity loop outputs gravity compensation torque based on the rotor's angular velocity and the load torque; the damping loop outputs damping compensation torque based on the wire rope's swing angle change rate and the load's vibration velocity; and the disturbance loop outputs oscillation compensation torque based on the trolley's feedforward acceleration and the wire rope length.

3. The lifting and hoisting control method based on a permanent magnet synchronous motor according to claim 1, characterized in that, In step 2, the angular acceleration curve includes an ascending curve and a descending curve. The feedforward angular acceleration of the rotor is extracted from the angular acceleration curve. The target torque is calculated by combining the feedforward loop, gravity loop and damping loop. The target current is calculated by combining the target torque and torque constant.

4. The lifting and hoisting control method based on a permanent magnet synchronous motor according to claim 1, characterized in that, In step 3, the operating parameters of the motor include the instantaneous current of the motor and the instantaneous angle of the rotor; the operating parameters of the load include the load vibration speed and the load torque; and the operating parameters of the wire rope include the swing angle and length of the wire rope.

5. The lifting and hoisting control method based on a permanent magnet synchronous motor according to claim 4, characterized in that, Instantaneous torque is calculated based on the instantaneous current of the motor, torque error is calculated based on the instantaneous torque and the target torque, load torque is updated based on the torque error, and then the gravity loop is updated.

6. The lifting and hoisting control method based on a permanent magnet synchronous motor according to claim 4, characterized in that, The theoretical angle is calculated based on the starting angle and rotor angular velocity. The angle error is calculated based on the instantaneous angle and the theoretical angle. The feedforward angular acceleration of the rotor is updated based on the angle error, and then the feedforward loop is updated.

7. The lifting and hoisting control method based on a permanent magnet synchronous motor according to claim 4, characterized in that, The rate of change of the swing angle of the wire rope is calculated based on the swing angle of the wire rope. The swing energy of the wire rope is calculated by combining the swing angle and the rate of change of the swing angle. The swing damping coefficient is updated based on the swing energy. The vibration energy of the load is calculated based on the load vibration velocity. The vibration damping coefficient is updated based on the vibration energy, and then the damping ring is updated.

8. The lifting and hoisting control method based on a permanent magnet synchronous motor according to claim 1, characterized in that, In step 5, multiple sets of direct-axis currents of the motor are collected, the current integral is calculated based on the multiple sets of direct-axis currents, and the torque constant is updated by combining the drive error and the current integral.

9. A lifting control system for implementing the lifting control method based on a permanent magnet synchronous motor as described in claim 1, characterized in that, include: A permanent magnet synchronous motor is configured to drive the load; The signal receiving unit is configured to receive external control signals; The rotor acquisition unit is configured to identify the rotor's starting angle and braking angle; The encoding acquisition unit is configured to identify the instantaneous angle of the rotor; The current acquisition unit is configured to acquire the instantaneous current of the motor; The wire rope acquisition unit is configured to acquire the swing angle of the wire rope; The vibration acquisition unit is configured to acquire the vibration velocity of the load; The data analysis unit is configured to generate the target torque for the motor; The lifting control unit is configured to generate the target current for the motor; The model update unit is configured to update the lifting and hoisting model; The register unit is configured to store model parameters of the lifting and hoisting model.

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