A multi-drive system cooperative control method and system based on improved bias coupling

Abstract

The application discloses a kind of based on improved deviation coupling Multi-drive system collaborative control method and system, it is related to Multi-drive system collaborative control technical field, including: constructing Multi-drive system model;Through speed tracking error and improved coupling deviation, the comprehensive deviation improved deviation coupling control strategy is obtained to the Multi-drive system model is carried out speed collaborative optimization;Quasi-sliding mode control algorithm is used to process initial instruction;Based on the initial instruction after processing and the optimized Multi-drive system model constructs collaborative controller;Drive control is carried out through the collaborative controller.The application establishes the mathematical model of Multi-drive system;Improved deviation coupling control strategy is designed;Improved deviation coupling control strategy and quasi-sliding mode technology are combined, and Multi-drive system collaborative controller is designed, can effectively solve the problem of Multi-drive system speed collaboration, and improve the tracking performance and robustness of system, realize the stable operation of Multi-drive system.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of multi-drive system cooperative control, and more particularly to a multi-drive system cooperative control method and system based on improved deviation coupling. BACKGROUND

[0002] At present, the existing multi-motor synchronization control method can only be applied to a multi-motor system, solves the synchronous operation of the multi-motor system, but cannot be applied to other multi-drive systems, and the existing motor synchronization control method cannot solve the problem of inconsistent speeds of the drive systems. Moreover, when establishing a mathematical model of the multi-drive system, the model precision of the commonly used theoretical modeling method is poor, and lacks theoretical guidance of real experiments, and cannot accurately reflect the real characteristics of the drive system.

[0003] Therefore, it is an urgent problem for those skilled in the art to propose a multi-drive system cooperative control method based on improved deviation coupling, which combines the improved deviation coupling control strategy and the quasi-sliding mode technology to improve the robustness, convergence speed and cooperative accuracy of the multi-drive system. SUMMARY

[0004] Therefore, the present application provides a multi-drive system cooperative control method based on improved deviation coupling, which combines the improved deviation coupling control strategy and the quasi-sliding mode technology to improve the robustness, convergence speed and cooperative accuracy of the multi-drive system. In order to achieve the above purpose, the present application adopts the following technical solutions:

[0005] A multi-drive system cooperative control method based on improved deviation coupling, comprising:

[0006] constructing a multi-drive system model;

[0007] processing an initial instruction using a quasi-sliding mode control algorithm;

[0008] obtaining a comprehensive deviation by a speed tracking error and an improved coupling deviation, and improving the deviation coupling control strategy to optimize the speed of the multi-drive system model;

[0009] constructing a cooperative controller based on the processed initial instruction and the optimized multi-drive system model;

[0010] driving control through the cooperative controller.

[0011] Optionally, the multi-drive system model comprises:

[0012]

[0013] wherein p is the number of pole pairs of the motor; ψ f is the rotor flux of the motor; J is the rotational inertia of the load; b is the viscous friction coefficient; ωi (t) is the speed of the i-th (i = 1, …, n) motor rotor; T L is the load torque of the motor.

[0014] Optionally, the step of processing the initial command by using the quasi-sliding mode control algorithm comprises:

[0015] defining an initial command error of the drive system;

[0016] defining a sliding surface switching function according to the initial command error of the drive system;

[0017] using a saturation function to represent a sign function in a sliding mode control exponential approach rate to constrain the initial command error.

[0018] Optionally, the step of verifying the stability of the sliding surface switching function by using a Lyapunov function comprises:

[0019] Optionally, the improved deviation coupling control strategy comprises:

[0020] defining a speed tracking error of the drive system;

[0021] optimizing a coupling deviation in the coupling deviation control system to obtain an improved coupling deviation;

[0022] weighting the speed tracking error of the drive system and the improved coupling deviation to obtain a comprehensive deviation of the drive system.

[0023] Optionally, the step of updating the coupling deviation of the drive system after calculating the comprehensive deviation comprises:

[0024] calculating a control amount by using a PID algorithm, and updating the coupling deviation of the drive system to obtain an actual control amount by using the PID algorithm, so as to simultaneously eliminate the speed tracking error of the drive system and the coupling deviation between the drive systems.

[0025] Optionally, a multi-drive system cooperative control system based on improved deviation coupling comprises:

[0026] a construction module for constructing a multi-drive system model;

[0027] an optimization module for processing an initial command by using a quasi-sliding mode control algorithm, obtaining a comprehensive deviation by using a speed tracking error and an improved coupling deviation, and improving a deviation coupling control strategy to optimize a speed of the multi-drive system model;

[0028] an integration module for constructing a cooperative controller based on the processed initial command and the optimized multi-drive system model;

[0029] Driving module: driving control is performed by the cooperative controller.

[0030] Compared with the prior art, the improved deviation coupling-based multi-drive system cooperative control method and system provided by the application has the following beneficial effects:

[0031] Compared with the prior art, the improved deviation coupling-based multi-drive system cooperative control method provided by the application can be applied to not only multi-motor systems but also other multi-drive systems, and can not only solve the synchronization problem of multi-drive systems but also solve the problem of accurate coordinated control under the condition of inconsistent speeds of each drive system.

[0032] When establishing a mathematical model of a multi-drive system, the application combines theoretical modeling and experimental methods, has higher model accuracy compared with common theoretical modeling methods, and has clearer theoretical guidance compared with experimental methods, and can more accurately reflect the real characteristics of the drive system.

[0033] The method provided by the application combines the improved deviation coupling control strategy and the quasi-sliding mode technology, and greatly improves the robustness, convergence speed and cooperation accuracy of the multi-drive system compared with the prior art. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only a part of the embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the provided drawings.

[0035] Figure 1 A flowchart of the improved deviation coupling-based multi-drive system cooperative control method provided by the application is shown.

[0036] Figure 2 A system framework diagram of the improved deviation coupling-based multi-drive system cooperative control system provided by the application is shown. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the application will be described clearly and completely below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only a part of the embodiments of the application, not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the application.

[0038] The embodiment of the application discloses a multi-drive system cooperative control method based on improved deviation coupling, comprising:

[0039] constructing a multi-drive system model;

[0040] processing an initial instruction by using a quasi-sliding mode control algorithm;

[0041] obtaining a comprehensive deviation improved deviation coupling control strategy by a speed tracking error and an improved coupling deviation, and performing speed cooperative optimization on the multi-drive system model;

[0042] constructing a cooperative controller based on the processed initial instruction and the optimized multi-drive system model;

[0043] performing drive control through the cooperative controller.

[0044] Further, the multi-drive system model comprises:

[0045]

[0046] wherein p is the pole pair number of the motor; ψ f is the rotor flux of the motor; J is the rotational inertia of the load; b is the viscous friction coefficient; ω i (t) is the speed of the i (i=1,…,n) motor rotor; T L is the load torque of the motor.

[0047] Further, the specific steps for processing the initial instruction by using the quasi-sliding mode control algorithm are as follows:

[0048] defining a drive system initial instruction error;

[0049] defining a sliding mode surface switching function according to the drive system initial instruction error;

[0050] using a saturation function to represent a sign function in a sliding mode control exponential approach rate to constrain the initial instruction error.

[0051] Further, the method comprises the following steps: verifying the stability of the sliding mode surface switching function by using a Lyapunov function, and making the sliding mode surface switching function finally stable on the sliding mode surface by satisfying a Lyapunov stability condition.

[0052] Further, the improved deviation coupling control strategy comprises:

[0053] defining a drive system speed tracking error;

[0054] optimizing a coupling deviation in a coupling deviation control system to obtain an improved coupling deviation;

[0055] The speed tracking error of the driving system and the improved coupling deviation are weighted to obtain a comprehensive deviation of the driving system.

[0056] Further, comprising:

[0057] The driving system adopts PID calculation to control the amount, and after calculating the comprehensive deviation, the coupling deviation of the driving system is updated, and the actual control amount is calculated by PID to synchronously eliminate the speed tracking error of the driving system and the coupling deviation between the driving systems.

[0058] In embodiment 1, an improved deviation coupling multi-driving system cooperative control method comprises:

[0059] Step 1: a mathematical model of the multi-driving system is established by combining theoretical modeling and experimental method.

[0060] Theoretical modeling can explicitly represent the mathematical model according to the physical parameters of the actuator and various physical laws, and is more intuitive in form, but the modeling process usually makes certain approximations and simplifications, resulting in certain errors between the modeling results and the actual system. The mathematical model of the multi-driving system established according to the physical law is as follows:

[0061]

[0062] Wherein, p is the number of pole pairs of the motor; ψ f is the rotor flux of the motor; J is the rotational inertia of the load; b is the viscous friction coefficient; ω i (t) is the speed of the i(i=1,…,n)th motor rotor; T L is the load torque of the motor.

[0063] Experimental method is to obtain the input-output relationship of the actual system by experimental measurement of the response of the actual system, which can reflect the true characteristics of the system, but lacks the understanding of the nature of the system. The combination of the two will complement each other, which can understand the nature of the system and obtain the accurate response characteristics of the actual system, and has higher guiding significance for subsequent cooperative control research.

[0064] Step 2: design an improved deviation coupling control strategy.

[0065] 2.1: define the speed tracking error of each driving system as:

[0066] e self =x d -x

[0067] Wherein, x d is the reference speed vector of each driving system; x is the actual speed vector of each driving system.

[0068] 2.2: In order to reduce the complexity of the control system, improve the real-time performance and reliability of the control system, the coupling error in the traditional deviation coupling control system is improved to:

[0069] e couple = P e self

[0070] wherein, is the coefficient matrix of the coupling error.

[0071] Therefore, when the improved coupling error e couple →0, it can be ensured that the tracking error of each drive system itself also converges to 0 synchronously, thereby achieving the purpose of eliminating the comprehensive error.

[0072] 2.3: The comprehensive error of each drive system can be obtained by weighted sum of the self-error and the improved coupling error of each drive system as follows:

[0073] e com = (1-α) e self +α e couple

[0074] wherein, α is the weight factor of the coupling error, and the value range is (0, 1).

[0075] 2.4: After calculating the comprehensive error, the control amount is obtained by PID calculation for each drive system, so as to realize the effect of synchronous elimination of the self-error and the coupling error between each drive system.

[0076] Step 3, in order to cope with the external disturbance, load change and other disturbances that the multi-drive system may face, a quasi-sliding mode control algorithm is used to process the initial command to obtain the motion command of each drive system.

[0077] 3.1: The initial command error of the multi-drive system is defined as follows:

[0078] e = q d -q

[0079] wherein, q d and q are the expected command and the actual response respectively.

[0080] 3.2: The sliding mode surface switching function is defined as:

[0081]

[0082] wherein, c is a constant greater than zero.

[0083] 3.3: The sign function in the sliding mode control exponential approach rate is replaced by a saturation function, and the following is obtained:

[0084]

[0085] wherein, ε is a constant greater than zero; k is a constant greater than zero; sat(·) is a saturation function, and the specific form is:

[0086]

[0087] wherein, Δ is a boundary layer parameter, and is a constant greater than zero.

[0088] 3.4: Taking Lyapunov function as

[0089]

[0090] wherein, is established. The derivative of both ends can be obtained as:

[0091]

[0092] It can be seen that is always true, and only when s = 0 Therefore, the Lyapunov stability condition is satisfied, and s will eventually stabilize on the sliding mode surface.

[0093] Step 4: Obtain the cooperative controller of the multi-drive system by combining the mathematical model of the multi-drive system as

[0094] wherein, C, B, A are the coefficient matrices of the mathematical model of the multi-drive system in the state space representation method, and x is the actual speed vector of each drive system.

[0095] In embodiment 2, a multi-drive system cooperative control system based on improved deviation coupling includes:

[0096] A construction module is configured to construct a multi-drive system model.

[0097] An optimization module is configured to process an initial instruction by using a quasi-sliding mode control algorithm, to obtain a comprehensive deviation improved deviation coupling control strategy by a speed tracking error and an improved coupling deviation, and to perform speed cooperative optimization on the multi-drive system model.

[0098] An integration module is configured to construct a cooperative controller based on the processed initial instruction and the optimized multi-drive system model.

[0099] A drive module is configured to perform drive control by using the cooperative controller.

[0100] The various embodiments described in this specification are presented for the purpose of illustration and description. Each of the embodiments described in this specification is presented as one or more exemplary embodiments. The various embodiments described in this specification can be combined with each other in any manner. Each of the embodiments described in this specification can be combined with other embodiments disclosed in the specification in any manner. The same or similar elements in the various embodiments are denoted by the same or similar reference numerals.

[0101] The above description of disclosed embodiments is intended to be illustrative and not restrictive. Many modifications and variations to the described embodiments will be apparent to those skilled in the art from this disclosure. The scope of the invention should be determined not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and patents are incorporated herein by reference in their entirety.

Claims

1. A method for cooperative control of a multi-drive system based on improved bias coupling, characterized in that, The method comprises the following steps: constructing a multi-drive system model; processing an initial instruction by using a quasi-sliding mode control algorithm; the specific steps of processing the initial instruction by using the quasi-sliding mode control algorithm are as follows: defining an initial instruction error of the drive system; defining a sliding surface switching function according to the initial instruction error of the drive system; using a saturation function to represent a sign function in a sliding mode control index approach rate to constrain the initial instruction error; optimizing a coupling deviation in a coupling deviation control system to obtain an improved coupling deviation; the improved coupling deviation control strategy comprises the following steps: defining a speed tracking error of the drive system; optimizing the coupling deviation in the coupling deviation control system to obtain the improved coupling deviation; weighting the speed tracking error of the drive system and the improved coupling deviation to obtain a comprehensive deviation of the drive system; the drive system uses a PID calculation to calculate a control amount, and after the comprehensive deviation is calculated, the coupling deviation of the drive system is updated, and an actual control amount is calculated by using the PID to synchronously eliminate the speed tracking error of the drive system and the coupling deviation between the drive systems; constructing a cooperative controller based on the processed initial instruction and the optimized multi-drive system model; driving control is performed through the cooperative controller.

2. The improved bias coupling-based cooperative control method for multi-drive systems according to claim 1, characterized in that, The multi-drive system model comprises the following steps: wherein, is the number of pole pairs of the electric machine; is the rotor flux of the electric machine; is the moment of inertia of the load; is the viscous friction coefficient; is the load torque of the electric machine. is the speed of the first electric machine rotor, is the load torque of the electric machine.​ 3. The improved bias coupling-based cooperative control method for multi-drive systems according to claim 1, characterized in that, The method comprises the following steps: stability of the sliding surface switching function is verified by using a Lyapunov function, and the sliding surface switching function is finally stabilized on a sliding surface by satisfying a Lyapunov stability condition.

4. A multi-drive system cooperative control system based on improved bias coupling, characterized in that, The method comprises the following steps: a construction module is configured to construct a multi-drive system model; an optimization module is configured to process an initial instruction by using a quasi-sliding mode control algorithm, and to optimize a coupling deviation in a coupling deviation control system to obtain an improved coupling deviation, and to weight a speed tracking error of the drive system and the improved coupling deviation to obtain a comprehensive deviation of the drive system, and to use a PID calculation to calculate a control amount, and after the comprehensive deviation is calculated, to update the coupling deviation of the drive system, and to calculate an actual control amount by using the PID to synchronously eliminate the speed tracking error of the drive system and the coupling deviation between the drive systems; the specific steps of processing the initial instruction by using the quasi-sliding mode control algorithm are as follows: defining an initial instruction error of the drive system; defining a sliding surface switching function according to the initial instruction error of the drive system; using a saturation function to represent a sign function in a sliding mode control index approach rate to constrain the initial instruction error; the improved coupling deviation control strategy comprises the following steps: defining a speed tracking error of the drive system; optimizing the coupling deviation in the coupling deviation control system to obtain the improved coupling deviation; weighting the speed tracking error of the drive system and the improved coupling deviation to obtain a comprehensive deviation of the drive system; the drive system uses a PID calculation to calculate a control amount, and after the comprehensive deviation is calculated, the coupling deviation of the drive system is updated, and an actual control amount is calculated by using the PID to synchronously eliminate the speed tracking error of the drive system and the coupling deviation between the drive systems; an integration module is configured to construct a cooperative controller based on the processed initial instruction and the optimized multi-drive system model; a driving module is configured to perform driving control through the cooperative controller.

Images