Adaptive locomotive adhesion control method based on acceleration threshold

Abstract

The application is a locomotive adhesion control method based on acceleration threshold adaptive mode, comprising the following steps: obtaining locomotive axle acceleration a i , traction torque reference value RefT q and acceleration reference value a_ref; using acceleration threshold adaptive control algorithm in adhesion control acceleration criterion, and realizing dynamic adjustment of following wheel acceleration according to torque reference instruction when locomotive actual wheel track adhesion is operated. The application dynamically searches locomotive adhesion acceleration according to locomotive actual wheel track adhesion condition, and dynamically adjusts acceleration threshold in acceleration criterion, so as to dynamically adjust locomotive wheel traction force before adhesion is destroyed, ensure that locomotive wheel traction force is stably exerted according to locomotive wheel track adhesion, and avoid large range fluctuation, and ensure locomotive traction force exertion.

Description

Technical Field

[0001] This invention belongs to the field of transportation locomotives and relates to a locomotive adhesion control method based on an adaptive acceleration threshold. Background Technology

[0002] Effective adhesion utilization is a crucial means to improve locomotive traction performance, and efficient adhesion utilization is the goal of adhesion control systems. Among existing adhesion control methods, the direct creep speed method is the simplest and most intuitive in principle. However, the creep speed required by the controller is difficult to obtain, especially in locomotive traction control. When the locomotive is not equipped with radar speed measurement, the controller cannot acquire an effective locomotive speed. The locomotive speed calculated by the software can only be used for peripheral protection in adhesion control and cannot serve as the core control target. In this case, adhesion control is mainly achieved by real-time acquisition of the locomotive's moving axle acceleration by the controller and by using acceleration criteria. This method is convenient, simple, and basically meets application needs.

[0003] In acceleration criteria, the conventional approach is to classify the dynamic shaft acceleration detected by the controller into different levels to determine different load reduction coefficients during adhesion actions. However, this acceleration classification cannot distinguish the locomotive load conditions. It can only estimate the approximate locomotive acceleration based on traction calculations and cannot accurately determine the acceleration threshold required for locomotive load reduction when wheel-rail adhesion is poor. If the threshold is too high, load reduction lag may occur, damaging adhesion. If the threshold is too low, misjudgment may occur, leading to frequent adhesion actions by the controller.

[0004] Technical solution of existing technology 1

[0005] In the existing high-power locomotive adhesion control technology acceleration criterion implementation method, a first acceleration point and a second acceleration point for adhesion action are preset. When the acceleration of the driving wheel is greater than the first acceleration, the traction force around the locomotive wheel begins to decrease. When the acceleration is greater than the second acceleration, the traction force around the wheel is decreased at the maximum slope. When the acceleration is between the first acceleration and the second acceleration, the traction force around the wheel is decreased according to the slope.

[0006] The implementation method is as follows:

[0007] Function: Uses acceleration to determine if idling has occurred; if idling has occurred, the motor torque needs to be adjusted.

[0008] Input parameter: wheelset acceleration a i traction torque T i .

[0009] Fixed parameter: Acceleration reference value, a_ref;

[0010] Output parameter: Traction torque correction ΔT i , i = 1...6.

[0011] 1. Preprocess the input data;

[0012] 2. Initialize a i and T i ;

[0013] 3. When a i When the torque is greater than or equal to a_ref, freewheeling occurs; adjust the torque until a_ref is reached. i <a_ref;

[0014] 4. When a i When ≤a_ref, exit the acceleration criterion;

[0015] The disadvantages of the existing technology are as follows:

[0016] In the existing acceleration criteria of high-power electric locomotive control technology in China, a pre-set adhesion acceleration method is used. The main drawbacks are: 1) the acceleration threshold in the acceleration criteria cannot be dynamically adjusted according to the locomotive load; 2) the acceleration threshold of the acceleration criteria cannot be dynamically adjusted according to the actual wheel-rail adhesion. An inappropriate acceleration threshold setting may cause complete loss of adhesion, requiring a re-search for adhesion, resulting in large fluctuations in the traction force around the locomotive wheels. Summary of the Invention

[0017] To address the issue of dynamically adjusting the acceleration threshold in the adhesion control acceleration criterion after considering idling, and dynamically adjusting the locomotive wheel circumference traction force based on the locomotive wheel-rail adhesion condition, and to solve the problem that after locomotive wheel-rail adhesion is damaged, the actual wheel-rail adhesion may not reach the threshold due to the large acceleration threshold in the acceleration criterion, requiring the locomotive to unload; otherwise, the adhesion will further deteriorate, leading to a large-scale adjustment of the locomotive traction force, which is not conducive to the effective use of locomotive traction force, the technical solution adopted in this invention is: a locomotive adhesion control method based on an adaptive acceleration threshold, comprising the following steps:

[0018] Obtain the locomotive driving axle acceleration a i Traction torque reference value RefT q And the acceleration reference value a_ref;

[0019] An adaptive control algorithm for acceleration threshold is adopted in the adhesion control acceleration criterion, and the acceleration of the follower wheel is dynamically adjusted based on the torque reference command when the locomotive’s actual wheel-rail adhesion action.

[0020] Furthermore: The process of using the adaptive control algorithm for acceleration threshold in the adhesion control acceleration criterion, and dynamically adjusting the follower wheel acceleration based on the torque reference command during the actual wheel-rail adhesion action of the locomotive, is as follows:

[0021] At time t1, the acceleration a of the locomotive's moving axle iIf (t1) ≥ a_ref, and the acceleration at time t1 lasts for a time Δt1, then the adhesion control acceleration threshold a_ref(t1+1+Δt1) = k1*a_ref and the traction torque setpoint RefT at the next time step are dynamically adjusted. q (t1+1+Δt1)=k2*RefT q k1 is the acceleration threshold adjustment coefficient, and k2 is the torque command adjustment coefficient;

[0022] When the acceleration reference value a_ref < a_refmin, then a_ref(t) = a_refmin, where a_refmin is the minimum limit value of a_ref;

[0023] At time t2, the acceleration a of the locomotive's moving axle i When (t2) < a_ref, and the duration is Δt2, then the adhesion control acceleration threshold and traction torque setpoint are dynamically increased at the next moment, a_ref(t2+1+Δt2)=k3*a_ref, RefT q (t2+1+Δt2)=k4*RefT q k3 is the acceleration threshold recovery coefficient, and k4 is the torque command recovery coefficient;

[0024] When the acceleration reference value a_ref > a_refmax, then a_ref = a_refmax, where a_refmax is the maximum limit value of a_ref.

[0025] Furthermore: 0 < k1 < 1, 0 < k2 < 1, 1 < k3 < 2, 1 < k4 < 2.

[0026] Furthermore: Δt1≥100ms; Δt2≥1000ms.

[0027] A locomotive adhesion control device based on an acceleration threshold adaptive method includes:

[0028] Acquisition module: used to acquire the locomotive's driving axle acceleration a i Traction torque reference value RefT q And the acceleration reference value a_ref;

[0029] Dynamic adjustment module: used to dynamically adjust the acceleration of the follower wheel by adopting the acceleration threshold adaptive control algorithm in the adhesion control acceleration criterion and the torque reference command when the locomotive is actually sticking to the rail.

[0030] A readable storage medium that stores a program module, which, when executed in a processor, can implement any of the methods described herein.

[0031] The locomotive adhesion control method based on acceleration threshold adaptive mode provided by this invention has the following advantages:

[0032] The present invention dynamically adjusts the locomotive torque setting based on the locomotive wheel-rail adhesion acceleration during locomotive adhesion action, thereby dynamically adjusting the locomotive wheel circumference traction setting according to the locomotive adhesion situation. This reduces the risk of excessive locomotive traction setting and large acceleration threshold in the acceleration criterion during locomotive adhesion action, which would lead to a significant reduction in locomotive traction force when the actual adhesion has been broken, resulting in a large range of adjustments in the locomotive wheel circumference traction force and affecting the performance of locomotive traction force.

[0033] This invention dynamically searches for locomotive adhesion acceleration based on the actual wheel-rail adhesion of the locomotive, and dynamically adjusts the acceleration threshold in the acceleration criterion. Before the locomotive adhesion is damaged, the traction force around the locomotive wheels is dynamically adjusted in advance to ensure that the traction force around the locomotive wheels is stably exerted according to the locomotive wheel-rail adhesion, so as not to have large fluctuations, and to ensure the traction force of the locomotive is exerted. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a flowchart of the method described in this application;

[0036] Figure 2 It is an action logic diagram based on the adhesion control algorithm. Detailed Implementation

[0037] It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0038] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] Figure 1This is a flowchart of the method described in this application;

[0040] A locomotive adhesion control method based on acceleration threshold adaptive approach includes the following steps:

[0041] S1: Obtain the locomotive's moving axle acceleration a i Traction torque reference value RefT q And the acceleration reference value a_ref;

[0042] S2: Adaptive control algorithm for acceleration threshold in adhesion control acceleration criterion is adopted, and dynamic adjustment of follower wheel acceleration is realized based on torque reference command during actual locomotive wheel-rail adhesion action.

[0043] Steps S1 and S2 are executed sequentially;

[0044] Furthermore: The process of using the adaptive control algorithm for acceleration threshold in the adhesion control acceleration criterion, and dynamically adjusting the follower wheel acceleration based on the torque reference command during the actual wheel-rail adhesion action of the locomotive, is as follows:

[0045] When the locomotive's moving axle accelerates at time t, the acceleration a i When (t)≥a_ref, the locomotive experiences idling. According to the locomotive adhesion control algorithm, the adhesion controller records the motor torque SpinT during the adhesion action. q Meanwhile, the motor torque follows NomT q Reduce load at a rate of 0.3, NomT q This refers to the rated torque of the motor.

[0046] At time t1, the acceleration a of the locomotive's moving axle i If (t1) ≥ a_ref, and the acceleration at time t1 lasts for a time Δt1, then the adhesion control acceleration threshold a_ref(t1+1+Δt1) = k1*a_ref and the traction torque setpoint RefT at the next time step are dynamically adjusted. q (t1+1+Δt1)=k2*RefT q k1 is the acceleration threshold adjustment coefficient, and k2 is the torque command adjustment coefficient; 0 < k1 < 1, 0 < k2 < 1.

[0047] When the acceleration reference value a_ref < a_refmin, then a_ref(t) = a_refmin, where a_refmin is the minimum limit value of a_ref;

[0048] When the traction torque reference value RefT q <RefT q min time, RefT q =RefT q min,RefT qmin is RefT q Minimum limit value.

[0049] And when the locomotive's moving axle is at time t, the acceleration a i When (t)≥a_ref, torque peak reduction processing S1 is performed according to the adhesion control acceleration criterion, see... Figure 2 As shown. Dynamically adjust the actual operating motor torque T. ramp =T ramp _NomT q / 0.3, when T ramp <RefTqmin,T ramp =RefTqmin, reduces circumferential traction and suppresses adhesion. T ramp The actual applied motor torque is represented by RefTqmin, which is the minimum torque command limit value.

[0050] Until detected and a i When the load drops to <0, the load reduction stops and the system enters the S2 torque holding stage.

[0051] At time t2, the acceleration a of the locomotive's moving axle i When (t2) < a_ref, and the duration is Δt2, then the adhesion control acceleration threshold and traction torque setpoint are dynamically increased at the next moment, a_ref(t2+1+Δt2)=k3*a_ref, RefT q (t2+1+Δt2)=k4*RefT q k3 is the acceleration threshold recovery coefficient, and k4 is the torque command recovery coefficient; 1 < k3 < 2, 1 < k4 < 2;

[0052] When the acceleration reference value a_ref > a_refmax, then a_ref = a_refmax, where a_refmax is the maximum limit value of a_ref.

[0053] This value is initially set to, for example, 0.6. During the adhesion action, it will drop to the minimum set value, for example, 0.3. During the adhesion recovery phase, it will gradually recover from 0.3 back to the original set value of 0.6.

[0054] When RefT q >RefT q When max, RefT q =RefT q max,RefT q `max` is the value given by the traction command.

[0055] When the locomotive's moving axle accelerates at time t, the acceleration a i When (t) < a_ref, according to the adhesion control acceleration recovery criterion, the torque recovery S3 stage begins, and T... ramp =Tramp +NomT q / 0.8, when T ramp When SpinTq*0.8, T ramp =T ramp +NomT q / 5,T ramp During the recovery process, it is determined whether the locomotive acceleration will trigger the adhesion unloading action again, until the traction force given by the locomotive handle is restored.

[0056] When T ramp ≥RefT q When max, RefT q =RefT q At max torque, the torque returns to normal, entering the S0 stage, RefT q `max` is the value given by the traction command.

[0057] When the wheel axle acceleration a i If the value is higher than the threshold a_ref, it indicates that the axis is spinning idly.

[0058] In this case, the adhesion control algorithm saves the actual torque as the idling torque (SpinT). q ), and enter state S1.

[0059] Figure 2 It is an action logic diagram based on adhesion control algorithm;

[0060] In state S1, the torque applied to the motor shaft is reduced at a torque derating rate of NomTq / 0.3 until the wheel axle acceleration a i Return to a state below the idling threshold a_ref. At this point, enter state S2.

[0061] In state S2, the torque remains constant until the wheel axle acceleration a i It becomes negative to reattach the idling axle; it will remain in this state for up to 200 milliseconds. At this point, it enters state S3.

[0062] In state S3, the torque increases at a torque loading rate of NomTq / 0.8 until the torque value equals 80% of the idle torque. The system then enters state S4.

[0063] In state S4, torque is restored using a torque loading rate of NomTq / 5 until the actual reference torque is reached. This completes the idling correction, and the system returns to state S0.

[0064] In any case, if wheel axle idling is detected again, the system will force entry into state S1, and the torque will begin to decrease again.

[0065] Furthermore: Δt1≥100ms; Δt2≥1000ms.

[0066] A locomotive adhesion control device based on an acceleration threshold adaptive method includes:

[0067] Acquisition module: used to acquire the locomotive's driving axle acceleration a i Traction torque reference value RefT q And the acceleration reference value a_ref;

[0068] Dynamic adjustment module: used to dynamically adjust the acceleration of the follower wheel by adopting the acceleration threshold adaptive control algorithm in the adhesion control acceleration criterion and the torque reference command when the locomotive is actually sticking to the rail.

[0069] A readable storage medium that stores a program module, which, when executed in a processor, can implement any of the methods described herein.

[0070] The acceleration threshold and torque reference are dynamically and adaptively adjusted during locomotive adhesion movements to reduce the impact of frequent adhesion movements on traction performance.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A locomotive adhesion control method based on an adaptive acceleration threshold, characterized in that: Includes the following steps: Obtain locomotive driving axle acceleration Traction torque reference value and acceleration reference value ; An adaptive control algorithm for acceleration threshold in the adhesion control acceleration criterion is adopted, and the acceleration of the follower wheel is dynamically adjusted based on the torque reference command during the actual wheel-rail adhesion action of the locomotive. The process of using the adaptive control algorithm for acceleration threshold in the adhesion control acceleration criterion, and dynamically adjusting the acceleration of the follower wheel based on the torque reference command during the actual wheel-rail adhesion action of the locomotive, is as follows: The acceleration of the locomotive's moving axle at time t1 Meanwhile, the acceleration continues at time t1. When the time interval is reached, the adhesion control acceleration threshold for the next time step is dynamically lowered. and traction torque setpoint , This is the acceleration threshold adjustment coefficient. The torque is given an adjustment factor; When the acceleration reference value At that time, , for Minimum limit; Acceleration at time t2 of locomotive driving axle At times, and continuously If the time is adjusted, the adhesion control acceleration threshold and traction torque setpoint for the next moment will be dynamically lowered. , , The acceleration threshold restitution coefficient, The torque is given a commanded recovery coefficient; When the acceleration reference value At that time, , for Maximum limit.

2. The locomotive adhesion control method based on acceleration threshold adaptive mode according to claim 1, characterized in that: ， ， ， 。 3. The locomotive adhesion control method based on acceleration threshold adaptive mode according to claim 1, characterized in that: ≥100ms; ≥1000ms。 4. The locomotive adhesion control method and apparatus based on acceleration threshold adaptive mode according to any one of claims 1-3, characterized in that: include: Acquisition module: used to acquire the acceleration of the locomotive's moving axle. Traction torque reference value and acceleration reference value ; Dynamic adjustment module: used to dynamically adjust the acceleration of the follower wheel by adopting the acceleration threshold adaptive control algorithm in the adhesion control acceleration criterion and the torque reference command when the locomotive is actually sticking to the rail.

5. A readable storage medium storing a program module, characterized in that, The program module, when run in a processor, can implement the method as described in any one of claims 1-3.

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