CN-122008892-A - Control method of high-speed magnetic levitation train lap suspension system

CN122008892ACN 122008892 ACN122008892 ACN 122008892ACN-122008892-A

Abstract

The application discloses a control method of a high-speed maglev train lap suspension system, and relates to the technical field of suspension system control. The method comprises the steps of decoupling a lap suspension system based on a constructed multi-degree-of-freedom coupling dynamics model, constructing a target extended state observer aiming at each single-point suspended float system after decoupling, estimating the state and total disturbance of the system according to suspension clearance errors in real time by using a smooth nonlinear function as a nonlinear feedback term by the target extended state observer, designing a sliding mode surface containing nonlinear power terms based on a nonsingular terminal sliding mode control theory, constructing a finite time control law according to the sliding mode surface, the estimated value of the total disturbance and a disturbance derivative compensation term, and generating composite control voltage and applying the composite control voltage to two ends of an electromagnet to control suspension clearances. The method has the advantages of strong robustness, high response speed and good engineering realizability, and the steady-state precision, dynamic stability and anti-interference capability of the maglev train under the high-speed operation working condition are obviously improved.

Inventors

LONG ZHIQIANG
LI ZIKANG
WANG HAIZHI
HUANG CUICUI
WANG ZHIQIANG
LI XIAOLONG
ZENG JIEWEI

Assignees

中国人民解放军国防科技大学

Dates

Publication Date: 20260512
Application Date: 20260414

Claims (10)

1. The control method of the lapping suspension system of the high-speed maglev train is characterized by comprising the following steps of: Construction of lap suspension systems a multi-degree-of-freedom coupling dynamics model; Decoupling the lap suspension system based on the multiple degree of freedom coupling dynamics model to convert into two independent single-point suspension systems; Constructing a target extended state observer aiming at each single-point suspended float system, wherein the target extended state observer adopts a smooth nonlinear function as a nonlinear feedback item, and estimates the system state and the total disturbance in real time according to the suspended clearance error; Based on a nonsingular terminal sliding mode control theory, a sliding mode surface containing a nonlinear power term is designed, a finite time control law is constructed according to the sliding mode surface, the estimated value of the total disturbance and a disturbance derivative compensation term, so that composite control voltage is generated and applied to two ends of an electromagnet of the lap-joint suspension system to control suspension gaps, and the disturbance derivative compensation term is used for estimating and counteracting the change rate of the total disturbance along with time.
2. The method for controlling a lapping suspension system of a high-speed maglev train according to claim 1, wherein the constructing a multi-degree-of-freedom coupling dynamics model of the lapping suspension system comprises: Establishing an electromagnet model based on an electromagnet physical structure, wherein the electromagnet model comprises an electromagnetic force equation and a voltage equation: Wherein, the method comprises the steps of, As the electromagnetic force, there is provided, For the suspension of the current of the electromagnet, For the distance between the levitation electromagnet and the track, Is the magnetic permeability of the vacuum and is equal to the magnetic permeability of the vacuum, For suspending the number of turns of the coil of the electromagnet, For the area of the magnetic pole of the suspension electromagnet, For the voltage applied across the electromagnet, The equivalent resistance value of the electromagnet; and establishing a suspension frame dynamics model according to the stress analysis of the lap joint suspension system, wherein the equation of the suspension frame dynamics model is as follows: wherein the subscripts l and r denote left and right, For suspending the electromagnet mass, x is the displacement of the electromagnet relative to the track, g represents the gravitational acceleration, Is a vertical acting force generated by a suspension system, As the electromagnetic force, there is provided, For the quality of the supporting arm, For the displacement of the bracket arm relative to the track, Is the acting force generated by the secondary suspension system, Is the equivalent mass of the car body, Indicating the displacement of the vehicle body relative to the track, Is an external disturbance; converting the dynamic model of the suspension frame into a state space form, wherein the expression of the state space form is as follows Wherein, the method comprises the steps of, , , , , , , Is a disturbance term; And For the stiffness and damping of a primary suspension system, For the lumped parameter to be a function of the total parameter, , , , 。
3. The method of claim 2, wherein decoupling the lap suspension system to convert to two independent single-point suspension systems based on the multiple degree of freedom coupling dynamics model comprises: Separating the coupling term from the non-coupling term in the state space form, wherein the separated state equation is as follows: Wherein, the method comprises the steps of, 、、 For a diagonal matrix, corresponding to the uncoupled term; 、、 A matrix with all zero main diagonal elements corresponds to the coupling term; Constructing a decoupling control matrix, and utilizing the decoupling control matrix to eliminate the coupling terms so as to decouple the lap suspension system into two independent single-point suspension subsystems, wherein the decoupling control matrix comprises K, M, S which respectively meet the following conditions: the state equation of the single-point suspended float system after decoupling is as follows: v is the control quantity of the system after decoupling, Is the total disturbance term after decoupling, wherein Is the coupling error.
4. The control method of a high-speed maglev train lap suspension system of claim 2, wherein constructing a target expanded state observer for each of the single-point suspension systems comprises: Constructing a target expansion state observer based on a hyperbolic tangent function, and taking a suspension clearance error as input to estimate the suspension clearance, the clearance speed and the total disturbance of each single-point suspension float system in real time; The expression of the target distention state observer is as follows: Wherein, the method comprises the steps of, , As an estimate of the levitation gap, As an estimate of the gap velocity, As an estimate of the total disturbance, Is a matrix Is selected from the group consisting of a first element of (c), Is a matrix Is selected from the group consisting of a first element of (c), 、、 For observer gain, η is a first parameter to be designed, σ is a second parameter to be designed, e is a suspension gap error, As a function of the sign of the symbol, 。
5. The method for controlling a high-speed maglev train lap levitation system of claim 4, further comprising: and configuring all poles of the target extended state observer to be the same target real number poles based on a bandwidth method so as to set the observer gain, wherein a setting formula of the observer gain is as follows: , , , wherein, Bandwidth for observer; Setting the first parameter to be designed as an initial value matched with the inertia of the single-point suspended float system, and adjusting the first parameter to be designed based on the initial value, wherein if the single-point suspended float system needs to improve the tracking capacity of the rapid change disturbance or the response speed of the system meets a first preset condition, the first parameter to be designed is increased, and if the composite control voltage oscillates or exceeds a preset amplitude control quantity, the first parameter to be designed is reduced; The second parameter to be designed is adjusted according to the noise level of the single-point suspended float system or by utilizing an adaptive strategy, wherein when the noise level is adjusted, if system measurement noise exists, the second parameter to be designed is reduced, if the convergence speed of the output of the target extended state observer needs to be improved, and the robustness of the target extended state observer meets a second preset condition under disturbance, the second parameter to be designed is increased, and when the noise level is adjusted based on the adaptive strategy, if the suspension gap error is increased, the second parameter to be designed is increased, and if the suspension gap error is reduced, the second parameter to be designed is reduced.
6. The method for controlling a lapping suspension system of a high-speed maglev train according to claim 1, wherein the designing a sliding mode surface containing nonlinear power terms based on a nonsingular terminal sliding mode control theory comprises: Defining a gap error between an actual value of the levitation gap and a reference value, and a velocity error between an actual value of the gap velocity and the reference value; Designing a sliding mode surface containing nonlinear power terms by utilizing the gap error and the speed error based on a nonsingular terminal sliding mode control theory; Wherein the gap error is , As an actual value of the levitation gap, Is a reference value of a suspension clearance, and the speed error is , As an actual value of the gap velocity, Is the reference value of the gap speed, and the sliding mode surface , wherein, Is of a proportional coefficient and , Is a nonlinear power term coefficient of a sliding mode surface, and 。
7. The method of claim 1, wherein constructing a finite time control law based on the slip plane, the estimated value of the total disturbance, and a disturbance derivative compensation term comprises: constructing a disturbance derivative compensation term; the disturbance derivative compensation term , wherein, Is that Is used as a first derivative of (a), Is a coefficient to be compensated and S is a slip-form surface, Is a gap error; constructing a control voltage expression based on the slip plane, the estimated value of the total disturbance, and a disturbance derivative compensation term to determine a finite time control law; The control voltage expression is: , In order to compound the control voltage, the control voltage is, Is a coefficient of proportionality and is used for the control of the power supply, Is a nonlinear power term coefficient of the sliding mode surface, In order to be a speed error, For the disturbance derivative compensation term, As an estimate of the total disturbance, In order for the desired acceleration to be fed forward, As a third parameter to be designed, As a sign function.
8. The method for controlling a high-speed maglev train lap levitation system of claim 7, further comprising: When the system state of the single-point suspension subsystem reaches the sliding mode surface, the limited time control law can enable the tracking error of the single-point suspension subsystem to dynamically meet a first convergence condition, and under the first convergence condition, the limited time for the system state to converge from an initial error to a balance point meets a second convergence condition; wherein the first convergence condition is that ; The second convergence condition is , For a limited convergence time period, Is the initial error.
9. The method for controlling a high-speed maglev train lap levitation system of claim 7, further comprising: fixing the nonlinear power term coefficient of the sliding mode surface as a preset initial value, selecting different proportional coefficients and third parameters to be designed, substituting the different proportional coefficients and the third parameters to be designed into the finite time control law, and performing simulation test; reducing the scaling factor when the single point suspended float system does not meet a first performance threshold to determine that the system response speed is insufficient; and when the single-point suspended float system does not meet a second performance threshold to judge that buffeting exists in the system, the proportionality coefficient and/or the third parameter to be designed are increased.
10. The method of controlling a high-speed maglev train bridging suspension system of any one of claims 1-9, wherein generating a composite control voltage and applying across electromagnets of the bridging suspension system to control levitation gap comprises: Discretizing the limited time control law by utilizing a forward Euler method, and embedding the discretized limited time control law into a suspension controller; Based on the suspension controller, real-time communication is carried out between the suspension controller and a suspension operation platform through a controller local area network bus so as to receive sensor data acquired by the suspension operation platform on line; And executing the discretized finite time control law by using the suspension controller according to the sensor data so as to output composite control voltage and apply the composite control voltage to two ends of an electromagnet of the lap suspension system to control a suspension gap.

Description

Control method of high-speed magnetic levitation train lap suspension system Technical Field The invention relates to the technical field of suspension system control, in particular to a control method of a high-speed magnetic levitation train lap suspension system. Background The high-speed magnetic levitation train realizes non-contact levitation and guidance by means of electromagnetic force, and a levitation system is a core subsystem for guaranteeing running stability, safety and riding comfort. Because the train is easily influenced by multiple uncertainty factors such as track irregularity, pneumatic disturbance, load change, parameter perturbation and the like in the high-speed running process, the suspension clearance is extremely easy to fluctuate, and even instability is caused. Therefore, it is important to implement real-time control of high robustness and high response speed for suspension systems. In recent years, active disturbance suppression control methods based on an extended state observer (Extended State Observer, ESO) have received attention in the field of magnetic levitation control because they can effectively estimate and compensate for internal and external disturbances of a system. However, the conventional ESO structure has the problems of low convergence speed, limited estimation accuracy and the like, and particularly, when the conventional ESO structure faces abrupt disturbance or strong nonlinear dynamics under high-speed operation, the dual requirements of the suspension system on rapidity and accuracy are difficult to meet. The conventional magnetic levitation suspension control strategy is mostly designed based on an asymptotic stability theory, although smaller levitation gap fluctuation can be effectively maintained in a steady state, response lag is obvious in a transient process (such as starting, braking, overbending or encountering sudden disturbance), a system state cannot be converged to an expected value in a limited time, dynamic performance of a train under a complex working condition is limited, a conventional ESO usually adopts a linear or fixed gain structure, contradiction between an estimated speed and noise sensitivity is difficult to consider, and control performance is reduced under a high-frequency disturbance environment, in addition, a high-speed magnetic levitation train levitation system takes a lapping structure as a minimum levitation unit, and the conventional control strategy for the high-speed magnetic levitation system is mostly based on a single-point levitation structure, so that coupling effect of an actual lapping structure is ignored. Therefore, it is needed to construct a lap suspension control scheme with limited time convergence, strong anti-interference performance and high calculation efficiency, so as to improve the dynamic response quality and the robust stability of the high-speed maglev train suspension system under severe running conditions. Disclosure of Invention Therefore, the invention aims to provide a control method of a high-speed magnetic levitation train lap-joint levitation system, which ensures that levitation gaps quickly converge in a limited time and effectively inhibits various disturbances by constructing an improved ESO with a nonlinear gain and bandwidth self-adaptive mechanism. The method has the advantages of strong robustness, high response speed and good engineering realizability, and the steady-state precision, dynamic stability and anti-interference capability of the maglev train under the high-speed operation working condition are obviously improved. The specific scheme is as follows: The application discloses a control method of a high-speed maglev train lap suspension system, which comprises the following steps: Construction of lap suspension systems a multi-degree-of-freedom coupling dynamics model; Decoupling the lap suspension system based on the multiple degree of freedom coupling dynamics model to convert into two independent single-point suspension systems; Constructing a target extended state observer aiming at each single-point suspended float system, wherein the target extended state observer adopts a smooth nonlinear function as a nonlinear feedback item, and estimates the system state and the total disturbance in real time according to the suspended clearance error; Based on a nonsingular terminal sliding mode control theory, a sliding mode surface containing a nonlinear power term is designed, a finite time control law is constructed according to the sliding mode surface, the estimated value of the total disturbance and a disturbance derivative compensation term, so that composite control voltage is generated and applied to two ends of an electromagnet of the lap-joint suspension system to control suspension gaps, and the disturbance derivative compensation term is used for estimating and counteracting the change rate of the total disturbance along with time. Optionally, the constructing