CN113291280A - Deceleration control method and system for electric friction hybrid braking power distribution of train - Google Patents
Deceleration control method and system for electric friction hybrid braking power distribution of train Download PDFInfo
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- CN113291280A CN113291280A CN202110495618.XA CN202110495618A CN113291280A CN 113291280 A CN113291280 A CN 113291280A CN 202110495618 A CN202110495618 A CN 202110495618A CN 113291280 A CN113291280 A CN 113291280A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
- B60T13/74—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with electrical assistance or drive
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Abstract
The invention provides a deceleration control method and a system for electric friction hybrid braking power distribution of a train, which comprises the following steps: receiving the electric braking force sent by the TCU to determine the braking condition of the train; and under the condition that the braking working condition is determined to be the electric friction hybrid braking working condition, determining the friction braking force according to the difference value of the total braking force and the electric braking force, and sending the friction braking force to the BCU so as to jointly perform electric friction hybrid braking on the train according to the friction braking force and the electric braking force. The invention manages the braking force of the train in a unified way through the TCMS, can complete the calculation of the friction braking force by communicating with the TCU to obtain the electric braking force once, and simultaneously carries out signal multiplexing through the acceleration speed information, carries out real-time measurement on the deceleration in the actual braking process of the vehicle, and carries out PID control on the actual deceleration and the target deceleration so as to complete the reapplication of new friction braking force once by the BCU, thereby effectively improving the braking response precision and the parking precision of the vehicle.
Description
Technical Field
The invention relates to the technical field of rail transit, in particular to a deceleration control method and system for electric friction hybrid braking power distribution of a train.
Background
The electric brake is often determined to be preferentially used at the beginning of the design of the train, and when only the electric brake capacity is insufficient, the braking force is supplemented by the friction brake.
When the current Train is subjected to electric-air hybrid braking, generally when the Train needs braking, a braking instruction of an Automatic Train Operation (ATO) System is transmitted to a Train Control and Management System (TCMS), and the TCMS transmits the braking instruction to a subway Train Traction Control Unit (TCU) and a Train braking Control System (BCU); the TCU calculates the electric braking force which can be exerted and transmits the value of the electric braking force which is actually exerted to the BCU, the BCU calculates the required total braking force according to the braking command sent by the TCMS and subtracts the received actual electric braking force sent by the TCU to obtain the friction braking force which needs to be supplemented, and the BCU evenly distributes the friction braking force which needs to be supplemented to each shaft (the brake adhesion limit of each shaft cannot be exceeded).
In the traditional train braking process, the calculation and distribution of the braking force involve the transmission of multiple signals among the TCMS, the TCU and the BCU, the application delay of the braking force is long, and if the friction coefficient between friction pairs is unstable after the friction braking is applied, the actual deceleration of a vehicle cannot well follow under the mixed action of the electric friction braking, so that the target value can fluctuate greatly, and the braking stability of the train is further seriously influenced.
Disclosure of Invention
Aiming at the defects existing in the existing train braking process, the embodiment of the invention provides a deceleration control method and a deceleration control system for electric friction hybrid braking power distribution of a train.
The invention provides a deceleration control method for electric friction hybrid braking power distribution of a train, which comprises the following steps: receiving the theoretical maximum value of the electric braking force sent by the subway vehicle traction control unit, and determining the braking condition of the train according to the theoretical maximum value of the electric braking force and the total braking force; the total braking force is determined based on the deceleration demand for braking the train; under the condition that the braking working condition of the train is determined to be an electric friction mixed braking working condition, determining theoretical friction braking force to be applied according to the difference value between the total braking force and the theoretical maximum value of the electric braking force; and sending the theoretical friction braking force to a train braking control system so that the train braking control system performs electric friction hybrid braking on the train together according to the theoretical friction braking force and the theoretical maximum value of the electric braking force.
According to the deceleration control method for electric friction hybrid braking power distribution of the train provided by the invention, after the theoretical friction braking force is sent to a train braking control system so as to jointly perform electric friction hybrid braking on the train by the train braking control system according to the theoretical friction braking force and by a metro vehicle traction control unit according to the theoretical maximum value of the electric braking force, the deceleration control method further comprises the following steps: acquiring the actual deceleration of the train in the braking process; and performing proportional integral derivative control on the actual deceleration and the target deceleration to adjust the actual friction braking force output by the train brake control system until the absolute value of the difference between the actual deceleration and the target deceleration is not greater than a first preset threshold value or the iteration number of the proportional integral derivative control reaches a second preset threshold value.
According to the deceleration control method for the electric friction hybrid braking power distribution of the train, provided by the invention, under the condition that the iteration number of the proportional integral derivative control reaches a second preset threshold value and the absolute value of the difference value between the actual deceleration and the target deceleration is greater than a first preset threshold value, a new deceleration requirement re-determined by an automatic train driving system is received; and according to the new deceleration requirement, completing the electric friction hybrid braking of the train again.
According to the deceleration control method for the train electric friction hybrid braking force distribution, the theoretical maximum value of the electric braking force sent by the subway vehicle traction control unit is received, so that the braking condition of the train is determined according to the theoretical maximum value of the electric braking force and the total braking force, and the deceleration control method comprises the following steps: determining the total braking force based on the deceleration demand to brake the train and the vehicle dynamic mass; sending the total braking force to the metro vehicle traction control unit to obtain the theoretical maximum value of the electric braking force fed back by the metro vehicle traction control unit; calculating the absolute value of the difference between the total braking force and the theoretical maximum value of the electric braking force; and determining the braking working condition of the train according to the absolute value of the difference.
According to the deceleration control method for the electric friction hybrid braking power distribution of the train provided by the invention, the step of determining the braking condition of the train according to the absolute value of the difference comprises the following steps: determining the braking working condition of the train to be a full electric braking working condition under the condition that the absolute value of the difference value is smaller than the minimum value of the friction braking force which can be output by the train braking control system; determining the braking working condition of the train to be a full electric braking working condition under the condition that the absolute value of the difference value is not less than the minimum value of the friction braking force which can be output by the train braking control system but less than a third preset threshold value; and under the condition that the absolute value of the difference value is not less than the minimum value of the friction braking force which can be output by the train braking control system and is not less than a third preset threshold value, determining that the braking working condition of the train is an electric friction hybrid braking working condition.
According to the deceleration control method of the electric friction hybrid braking force distribution of the train provided by the invention, when the absolute value of the difference is smaller than the minimum value of the friction braking force which can be output by the train braking control system, the deceleration control method further comprises the following steps: controlling the subway vehicle traction control unit to reduce the theoretical maximum value of the electric braking force, so that a new difference absolute value determined by the reduced theoretical maximum value of the electric braking force is not less than the minimum value of the friction braking force which can be output by the train braking control system and is not less than a third preset threshold value; and determining the braking working condition of the train as an electric friction hybrid braking working condition.
According to the deceleration control method of the train electric friction hybrid braking power distribution provided by the invention, the proportional integral derivative control is carried out on the actual deceleration and the target deceleration so as to adjust the actual friction braking force output by the train braking control system until the absolute value of the difference between the actual deceleration and the target deceleration is not larger than a first preset threshold value or the iteration number of the proportional integral derivative control reaches a second preset threshold value, and the deceleration control method comprises the following steps: acquiring the actual friction braking force corresponding to the actual deceleration and the theoretical friction braking force corresponding to the target deceleration to determine a friction braking force control value; the friction braking force control value is the absolute value of the difference between the theoretical friction braking force and the actual friction braking force; determining a new theoretical friction braking force according to the actual deceleration, the target deceleration and the difference absolute value based on proportional integral derivative control; according to the new theoretical friction braking force and the theoretical maximum value of the electric braking force, electric friction hybrid braking is carried out on the train together, and new actual deceleration is obtained again; iteratively executing the acquiring of the actual friction braking force corresponding to the actual deceleration and the theoretical friction braking force corresponding to the target deceleration to re-determine a friction braking force control value until a new actual deceleration is acquired until an absolute value of a difference between the new actual deceleration and the target deceleration is not greater than a first preset threshold or the number of iterations of the proportional-integral-derivative control reaches a second preset threshold.
The invention also provides a deceleration control system for distributing the electric friction mixed braking force of the train, which comprises: the braking condition determining unit is used for receiving the theoretical maximum value of the electric braking force sent by the subway vehicle traction control unit so as to determine the braking condition of the train according to the theoretical maximum value of the electric braking force and the total braking force; the total braking force is determined according to a deceleration demand which is a train brake; the friction braking force determining unit is used for determining theoretical friction braking force to be applied according to the difference value between the total braking force and the theoretical maximum value of the electric braking force under the condition that the braking working condition of the train is determined to be an electric friction mixed braking working condition; and the hybrid brake control unit is used for sending the theoretical friction braking force to a train brake control system so as to jointly perform electric friction hybrid braking on the train by the train brake control system according to the theoretical friction braking force and by the subway vehicle traction control unit according to the theoretical maximum value of the electric braking force.
The invention also provides an electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor implements the steps of the deceleration control method for the electric friction hybrid braking power distribution of the train as described in any one of the above when executing the program.
The present invention also provides a non-transitory computer readable storage medium having stored thereon a computer program which, when executed by a processor, implements the steps of a deceleration control method of a train electric friction hybrid braking power distribution as described in any one of the above.
The invention provides a deceleration control method and a system for train electric friction hybrid braking force distribution, which can realize unified management of train braking force through TCMS, complete calculation of friction braking force through once obtaining electric braking force through communication with a TCU, simultaneously carry out signal multiplexing through acceleration speed information, carry out real-time measurement on deceleration in the actual braking process of a vehicle, carry out PID control on actual deceleration and target deceleration, complete reapplication of new friction braking force by a BCU, and effectively improve the braking response precision and parking precision of the vehicle.
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In order to more clearly illustrate the technical solutions of the present invention or the prior art, the drawings needed for the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to the drawings without creative efforts.
FIG. 1 is a schematic flow chart of a deceleration control method for electric friction hybrid braking power distribution of a train according to the present invention;
FIG. 2 is a second schematic flow chart of the deceleration control method for electric friction hybrid braking power distribution of the train according to the present invention;
FIG. 3 is a schematic diagram of a deceleration control system for electric friction hybrid braking force distribution of a train provided by the present invention;
fig. 4 is a schematic structural diagram of an electronic device provided in the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that in the description of the embodiments of the present invention, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element. The terms "upper", "lower", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the referred devices or elements must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
The deceleration control method and system for electric friction hybrid braking power distribution of a train provided by the embodiment of the invention are described in the following by combining with figures 1-4.
Fig. 1 is a schematic flow chart of a deceleration control method for electric friction hybrid braking power distribution of a train according to the present invention, as shown in fig. 1, including but not limited to the following steps:
step S1: receiving the theoretical maximum value of the electric braking force sent by the TCU, and determining the braking condition of the train according to the theoretical maximum value of the electric braking force and the total braking force; the total braking force is determined according to a deceleration demand which is a train brake;
step S2: under the condition that the braking working condition of the train is determined to be an electric friction mixed braking working condition, determining theoretical friction braking force to be applied according to the difference value between the total braking force and the theoretical maximum value of the electric braking force;
step S3: and sending the theoretical friction braking force to a BCU (binary coded decimal) so that the BCU jointly performs electric friction hybrid braking on the train according to the theoretical friction braking force and the TCU according to the theoretical maximum value of the electric braking force.
The present invention is an expression of deceleration Control for distributing electric friction hybrid braking force of a Train, which is implemented by using a Train Control and Management System (TCMS) as an execution subject.
Specifically, after a braking demand level is issued by an Automatic Train Operation (ATO) or an aircraft, a corresponding deceleration demand a _ e is generated. After receiving the deceleration demand a _ e, the TCMS can correspondingly calculate the total braking force F for realizing train brakingt:
Ft=m-dy*a-e;
Where m-dy is the vehicle dynamic mass at braking and a-e is the deceleration demand.
Then, the TCMS applies the total braking force FtSent to the TCU, which depends on the total braking force F receivedtCalculating the theoretical maximum value F of the electric braking force capable of being exertedED-MAXAnd fed back to the TCMS.
Note that, in general, FED-MAXThe transmission of (a) may be after the vehicle is started from stall, the vehicle is in traction or coasting phase, and may be calculated by the TCU and transmitted to the TCMS before the next braking. Thus, F can be accomplished in advanceED-MAXAnd storing the calculated value in the TCMS for each braking, so that the application delay of the braking force can be effectively reduced, and the braking stability of the vehicle is further improved.
After the actual braking process begins, the train needs to realize the total braking force F for braking the traintWith the theoretical maximum value F of the electric braking force that can be exertedED-MAXThe relationship between the brake pedal and the brake pedal, to determine the braking condition to be taken for the entire braking.
Wherein the braking condition may include: the system comprises a full electric braking working condition and an electric friction hybrid braking working condition (under a special condition, if the electric braking is seriously failed, the full friction braking working condition can be generated, but when the condition is generated, a more serious result can be generated).
Fig. 2 is a second flowchart of the deceleration control method for electric friction hybrid braking power distribution of a train according to the present invention, and the TCMS may determine, according to the logic shown in fig. 2, whether the braking condition required by the current braking of the train is the full electric braking condition or the electric friction hybrid braking condition.
In step S2, when the braking condition of the train is determined to be the electric friction hybrid braking condition (or the full friction braking condition, the theoretical maximum value F of the electric braking force may be determined at this timeED-MAXConsidered as 0), the total braking force F can be based on the train brakingtWith the theoretical maximum value F of the electric braking force that can be exertedED-MAXDifference between them to determine the theoretical friction braking force F that needs to be supplemented by BCUEP-possibleTo the BCU, wherein:
FEP-possible=Ft-FED-MAX。
finally, the BCU receives the theoretical friction braking force FEP-possibleAnd is determined by the TCU on the basis of the determined theoretical maximum value F of the electric braking forceED-MAXAnd jointly executing electric friction hybrid braking.
The invention provides a deceleration control method for train electric friction hybrid braking force distribution, which is characterized in that train braking force is uniformly managed through a TCMS (train control system), the calculation of the friction braking force can be completed by communicating with a TCU (train control unit) to obtain the electric braking force once, signals are multiplexed through acceleration speed information, the deceleration in the actual braking process of a vehicle is measured in real time, the actual deceleration and the target deceleration are subjected to PID (proportion integration differentiation) control, so that a BCU (binary control unit) completes the reapplication of a new friction braking force, and the braking response precision and the stopping precision of the vehicle can be effectively improved.
Based on the contents of the above-described embodiment, as an alternative embodiment, the theoretical frictional braking force F is setEP-possibleIs sent to the BCU to generate the braking force F according to the theoretical friction by the BCUEP-possibleAnd by the metro vehicle traction control unit according to the theoretical maximum value F of the electric braking forceED-MAXAfter the electric friction hybrid braking is carried out on the train together, the method further comprises the following steps:
acquiring the actual deceleration of the train in the braking process; and performing Proportional-Integral-Derivative Control on the actual deceleration and the target deceleration to adjust the actual friction braking force output by the BCU until the absolute value of the difference between the actual deceleration and the target deceleration is not greater than a first preset threshold value, or the iteration number of the Proportional-Integral-Derivative Control (PID Control) reaches a second preset threshold value.
Specifically, as shown in fig. 2, during the actual braking process of the train, during the application of the friction braking force by the BCU, the TCU will also apply the corresponding electric braking force to jointly realize the braking of the train. Actual electric braking force F of trainED-actualAnd an actual deceleration a _ s is generated under the combined action of the actual friction braking force and the actual deceleration. The actual applied braking force, i.e. the actual electric braking force F, can be detected by the TCU in real timeED-actualAnd the actual deceleration a _ s of the train is collected in real time by an accelerometer mounted on the vehicle.
The TCMS receives the actual electric braking force F uploaded by the TCU in real timeED-actualAnd receiving the actual deceleration a _ s uploaded by the accelerometer in real time, and combining with the pre-designed deceleration requirement a _ e to adopt a PID control method to realize the acceleration adjustment of the electric friction hybrid braking of the train.
The actual deceleration a _ s is acquired in real time through an accelerometer installed on the vehicle and is sent to the TCMS, and the TCMS compares the deceleration received in real time with the target deceleration and judges the deceleration through PID control as shown in the figure.
Such as: and if the first preset threshold value is set to be 0.05, the whole braking process is controlled by the PID under the condition that the delta a is | a-s-a-e | is >0.05, the deceleration meets the requirement until the delta a is | a-s-a-e | is less than or equal to 0.05, and the PID does not act. In the process of executing the PID control, after the PID control loops through the second preset threshold (for example, 3 times), the real-time deceleration of the train still cannot meet the deceleration deviation requirement, and then the PID control abandons the continuous control.
As an alternative embodiment, in the case where the number of iterations of the PID control reaches a second preset threshold and the absolute value of the difference between the actual deceleration and the target deceleration is greater than a first preset threshold, a new deceleration demand that is newly determined by an Automatic Train Operation (ATO) is received; and according to the new deceleration requirement, completing the electric friction hybrid braking of the train again.
Specifically, in the process of executing the PID control, after the PID control loops through the second preset threshold (e.g., 3 times), the real-time deceleration of the train still cannot meet the deceleration deviation requirement, and then the PID control abandons the continuous control, and instead, the ATO recalculates the target deceleration of the train to generate and output a new target deceleration a-s'.
Further, the distribution of braking force is restarted by the TCMS according to the new target deceleration a-s' until the deviation requirement is met by the actual deceleration and the target deceleration of the train.
The deceleration control method provided by the invention generally manages the train braking force in a unified way through the TCMS, only the TCMS and the TCU need to communicate once to obtain an actual electric braking force value signal to complete the calculation of the friction braking force, meanwhile, the signal multiplexing is carried out on an accelerometer arranged on a train by a signal system, the deceleration in the actual braking process of the train is measured in real time, the measured information is sent to the TCMS through a Remote Input/Output module (RIOM), according to the braking force control distribution logic, after the electric braking force is locked, the TCMS carries out PID control on the actual deceleration and the target deceleration and outputs the friction braking force needing to be readjusted, and the braking force is sent to the BCU again, and the BCU completes the reapplication of a new friction braking force. The braking response precision and the parking precision of the vehicle can be effectively improved through the deceleration closed-loop control.
Compared with the traditional braking force response method, the deceleration control method for the electric friction hybrid braking force distribution of the train provided by the invention is equivalent to that the train performs fine multiple fine control according to the target deceleration requirement, and compared with the traditional one-time response braking mode, the deceleration control method can enable the braking performance of the train to meet the target requirement.
Based on the content of the foregoing embodiment, as an alternative embodiment, the receiving the theoretical maximum value of the electric braking force sent by the subway vehicle traction control unit to determine the braking condition of the train according to the theoretical maximum value of the electric braking force and the total braking force includes: TCMS determines the total braking force F from the deceleration demand a-s for braking the train and the vehicle dynamic masst(ii) a Will total braking force FtIs sent to the TCU to obtain the theoretical maximum value F of the electric braking force fed back by the TCUED-MAX(ii) a Calculating the total braking force FtWith said theoretical maximum value F of electric braking forceED-MAXThe absolute value of the difference between; and determining the braking condition of the train according to the absolute value of the difference.
As an optional embodiment, the determining the braking condition of the train according to the absolute value of the difference mainly includes:
when the absolute value of the difference is smaller than the minimum value F of the friction braking force which can be output by the BCUEP-minUnder the condition of (3), determining the braking working condition of the train to be a full electric braking working condition;
when the absolute value of the difference is not less than the minimum value F of the friction braking force which can be output by the BCUEP-minIf the braking condition is smaller than the third preset threshold value, determining that the braking condition of the train is a full electric braking condition;
when the absolute value of the difference is not less than the minimum value F of the friction braking force which can be output by the BCUEP-minAnd under the condition that the braking condition of the train is not less than a third preset threshold value, determining the braking condition of the train to be an electric friction hybrid braking condition.
As shown in fig. 2, in which the friction braking force is at a minimum value FEP-minMeans friction that the BCU can outputMinimum value of braking, friction braking force applied if required (i.e. F)tAnd FED-MAXThe difference therebetween) is lower than the value, the BCU performs a process that does not achieve the actual application of the braking force even if it executes the command to apply the friction braking force.
Specifically, if the train can output the total electric braking force FED-MAXFail to satisfy the total braking force FtIf the friction braking force is less than F, the friction braking force needs to be supplemented appropriately, but if the supplemented friction braking force is less than FEP-minThe vehicle enters a full electric brake condition.
At this time, if the difference between the actual deceleration of the train and the target deceleration Δ a is within the allowable range, i.e., less than the third preset threshold value, the all-electric brake condition is performed.
And if the difference value between the actual deceleration of the train and the target deceleration delta a is not within the allowable range, namely is greater than or equal to a third preset threshold value, determining that the train adopts the electric friction hybrid braking condition.
As an alternative embodiment, the absolute value of the difference is smaller than the minimum value F of the friction braking force which can be output by the BCUED-MAXIn the case of (3), the deceleration control method provided by the present invention may further include:
controlling TCU to reduce theoretical maximum value F of electric braking forceED-MAXSo that the new absolute value of the difference determined by the reduced theoretical maximum value of the electric braking force is not less than the minimum value F of the friction braking force which can be output by the BCUEP-minAnd is not less than a third preset threshold; and determining the braking condition of the train as an electric friction hybrid braking condition.
Specifically, in the present invention, if the difference between the actual deceleration of the train and the target deceleration Δ a is greater than or equal to the third preset threshold, the TCMS needs to consult the scheme with the TCU and the BCU in designing the communication.
For example: the supplementary friction braking force calculated by TCU is less than FEP-minIn time, the TCU can properly reduce the theoretical maximum value of the electric braking force to execute the real electric friction braking force hybrid braking.
In addition, the total electric braking force of the train is larger than the total braking force demand, the friction braking force does not need to be supplemented to the vehicle, and the train brake executes full electric braking.
It should be noted that the present TCMS performs PID control in a manner different from PID control of a conventional ATO, which is targeted for deceleration; however, the PID control target in the TCMS of the present invention is the braking force, that is, the actual frictional braking force output by the BCU is controlled to achieve the purpose of adjusting the actual deceleration.
Optionally, the deceleration control method for distributing the electric friction hybrid braking power of the train according to the present invention may be implemented by using an integrated control platform obtained by fusing ATO and TCMS, wherein: the PID control of ATO and the PID control of TCMS can be fused on one core processor.
According to the deceleration control method for distributing the electric friction hybrid braking force of the train, the electric braking force and the friction braking force of the train are managed and calculated in a unified mode through the TCMS, transmission calculation delay among multiple systems is reduced, the electric friction hybrid braking force in the braking process is managed and distributed, and braking response precision and stopping precision of the train can be effectively improved.
Based on the contents of the above-described embodiment, as an alternative embodiment, the actual deceleration a-s and the target deceleration a-e are PID-controlled to adjust the actual friction braking force F output from the BCUED-actualUntil the absolute value of the difference between the actual deceleration a-s and the target deceleration a-s is not larger than a first preset threshold or the number of iterations of proportional PID control reaches a second preset threshold, the method comprises the following steps:
acquiring actual friction braking force F corresponding to actual deceleration a-sEP-actualAnd a theoretical frictional braking force F corresponding to the target deceleration a-eEP-possibleTo determine a friction braking force control value; the friction braking force control value is the absolute value of the difference between the theoretical friction braking force and the actual friction braking force; determining a new theoretical friction braking force F according to the actual deceleration a-s, the target deceleration a-e and the absolute value of the difference value based on PID controlEP-possible'; according to the new theoretical friction braking force FEP-possible', and the theoretical maximum value F of the electric braking forceED-MAXJointly performing electric friction hybrid braking on the train, and acquiring new actual deceleration a-s'; iteratively executing the step of acquiring the actual friction braking force corresponding to the actual deceleration and the theoretical friction braking force corresponding to the target deceleration to re-determine the friction braking force control value until a new actual deceleration is acquired until an absolute value of a difference between the new actual deceleration and the target deceleration is not greater than a first preset threshold or the number of iterations of the proportional-integral-derivative control reaches a second preset threshold.
Specifically, as shown in fig. 2, during the application of the friction braking force by the BCU, the electrical braking force F that the TCU will actually applyED-actualAlso sent to TCMS, train at FED-actualAnd actual friction braking force FEP-actualTo generate an actual deceleration a-s under the combined action of the two;
the actual deceleration a-s is acquired in real time through an accelerometer installed on the vehicle and is sent to the TCMS, the TCMS compares the received real-time deceleration a-s with the target deceleration a-e and judges through PID control in FIG. 2, and if Da is 1/2a _ s-a _ e1/2 which is greater than 0.05, the PID control acts; if Δ a ≦ a-s-a-e ≦ 0.05, then the deceleration is satisfactory and the PID is inactive.
When the PID control is activated, the friction braking force control value F needs to be a control target, i.e., the friction braking force control value of the friction braking forceEP-targetThe calculation is as follows:
FEP-target=Ft-FED-actual;
through PID control, TCMS outputs a theoretical friction braking force FEP-possible' theoretical frictional braking force F of trainEP-possible' and actual electric braking force FED-actualUnder the combined action of the two-step deceleration, a new real-time deceleration a-s' is generated;
if the difference between the new real-time deceleration a-s' and the target deceleration a-e meets the following requirement: if delta a is a-s-a-e is greater than 0.05, the deceleration control of the train is finished, and the vehicle realizes smooth braking; if the difference requirement is not met, the PID control is performed in a circulating mode;
if the real-time deceleration of the train still can not meet the deceleration deviation requirement after the PID control is circulated for 3 times, the PID control abandons the continuous control, the ATO recalculates the target deceleration of the train, outputs a new target deceleration a-s ', and the TCMS restarts the distribution of the braking force according to the new target deceleration a-s'; until the actual deceleration and the target deceleration of the train meet the deviation requirement.
The deceleration control method for distributing the electric friction hybrid braking power of the train provided by the invention simultaneously utilizes the accelerometer arranged on the train to multiplex signals and carry out closed-loop control on the deceleration in the braking process, realizes the management and distribution of the electric friction hybrid braking power in the braking process, and can effectively improve the braking response precision and the stopping precision of the train.
Fig. 3 is a schematic structural diagram of a deceleration control system for distributing electric friction hybrid braking force of a train provided by the present invention, and as shown in fig. 3, the deceleration control system mainly comprises a braking condition determining unit 31, a friction braking force determining unit 32 and a hybrid braking control unit 33, wherein:
the braking condition determining unit 31 is mainly used for receiving the theoretical maximum value of the electric braking force sent by the subway vehicle traction control unit, and determining the braking condition of the train according to the theoretical maximum value of the electric braking force and the total braking force; the total braking force is determined according to a deceleration demand which is a train brake; the friction braking force determining unit 32 is mainly used for determining theoretical friction braking force to be applied according to a difference value between the total braking force and the theoretical maximum value of the electric braking force under the condition that the braking working condition of the train is determined to be an electric friction mixed braking working condition; the hybrid brake control unit 33 is mainly configured to send the theoretical friction braking force to a train brake control system, so that the train brake control system performs electric friction hybrid braking on the train together according to the theoretical friction braking force and according to the theoretical maximum value of the electric braking force by the subway vehicle traction control unit.
It should be noted that, when specifically executed, the deceleration control system for distributing the electric friction hybrid braking force of the train according to the embodiment of the present invention may be implemented based on the deceleration control method for distributing the electric friction hybrid braking force of the train according to any of the above embodiments, and details of this embodiment are not repeated.
The deceleration control system for distributing the electric friction mixed braking force of the train provided by the invention has the advantages that the train braking force is uniformly managed through the TCMS, the calculation of the friction braking force can be completed by acquiring the electric braking force once through communication with the TCU, meanwhile, the signal multiplexing is performed through the acceleration speed information, the deceleration in the actual braking process of the train is measured in real time, the PID control is performed on the actual deceleration and the target deceleration, so that the BCU completes the reapplication of a new friction braking force, and the braking response precision and the parking precision of the train can be effectively improved.
Fig. 4 is a schematic structural diagram of an electronic device provided in the present invention, and as shown in fig. 4, the electronic device may include: a processor (processor)410, a communication Interface 420, a memory (memory)430 and a communication bus 440, wherein the processor 410, the communication Interface 420 and the memory 430 are communicated with each other via the communication bus 440. The processor 410 may invoke logic instructions in the memory 430 to perform a deceleration control method of a train electric friction hybrid braking power distribution, the method comprising: receiving the theoretical maximum value of the electric braking force sent by the traction control unit TCU of the subway vehicle, and determining the braking condition of the train according to the theoretical maximum value of the electric braking force and the total braking force; the total braking force is determined based on the deceleration demand for braking the train; under the condition that the braking working condition of the train is determined to be an electric friction mixed braking working condition, determining theoretical friction braking force to be applied according to the difference value between the total braking force and the theoretical maximum value of the electric braking force; and sending the theoretical friction braking force to a train braking control system BCU (brake control unit) so as to jointly perform electric friction hybrid braking on the train by the train braking control system according to the theoretical friction braking force and the theoretical maximum value of the electric braking force by the subway vehicle traction control unit.
In addition, the logic instructions in the memory 430 may be implemented in the form of software functional units and stored in a computer readable storage medium when the software functional units are sold or used as independent products. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.
In another aspect, the present invention also provides a computer program product comprising a computer program stored on a non-transitory computer readable storage medium, the computer program comprising program instructions which, when executed by a computer, enable the computer to execute the deceleration control method for electric friction hybrid braking power distribution of a train provided by the above methods, the method comprising: receiving the theoretical maximum value of the electric braking force sent by the traction control unit TCU of the subway vehicle, and determining the braking condition of the train according to the theoretical maximum value of the electric braking force and the total braking force; the total braking force is determined based on the deceleration demand for braking the train; under the condition that the braking working condition of the train is determined to be an electric friction mixed braking working condition, determining theoretical friction braking force to be applied according to the difference value between the total braking force and the theoretical maximum value of the electric braking force; and sending the theoretical friction braking force to a train braking control system BCU (brake control unit) so as to jointly perform electric friction hybrid braking on the train by the train braking control system according to the theoretical friction braking force and the theoretical maximum value of the electric braking force by the subway vehicle traction control unit.
In yet another aspect, the present invention further provides a non-transitory computer readable storage medium having stored thereon a computer program, which when executed by a processor, is implemented to perform the deceleration control method for electric friction hybrid brake distribution of a train provided in the above embodiments, the method including: receiving the theoretical maximum value of the electric braking force sent by the traction control unit TCU of the subway vehicle, and determining the braking condition of the train according to the theoretical maximum value of the electric braking force and the total braking force; the total braking force is determined based on the deceleration demand for braking the train; under the condition that the braking working condition of the train is determined to be an electric friction mixed braking working condition, determining theoretical friction braking force to be applied according to the difference value between the total braking force and the theoretical maximum value of the electric braking force; and sending the theoretical friction braking force to a train braking control system BCU (brake control unit) so as to jointly perform electric friction hybrid braking on the train by the train braking control system according to the theoretical friction braking force and the theoretical maximum value of the electric braking force by the subway vehicle traction control unit.
The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.
Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware. With this understanding in mind, the above-described technical solutions may be embodied in the form of a software product, which can be stored in a computer-readable storage medium such as ROM/RAM, magnetic disk, optical disk, etc., and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the methods described in the embodiments or some parts of the embodiments.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (10)
1. A deceleration control method for electric friction hybrid braking power distribution of a train is characterized by comprising the following steps:
receiving the theoretical maximum value of the electric braking force sent by the subway vehicle traction control unit, and determining the braking condition of the train according to the theoretical maximum value of the electric braking force and the total braking force; the total braking force is determined according to a deceleration demand which is a train brake;
under the condition that the braking working condition of the train is determined to be an electric friction mixed braking working condition, determining theoretical friction braking force to be applied according to the difference value between the total braking force and the theoretical maximum value of the electric braking force;
and sending the theoretical friction braking force to a train braking control system, so that the train braking control system jointly performs electric friction hybrid braking on the train according to the theoretical friction braking force and the theoretical maximum value of the electric braking force by a subway vehicle traction control unit.
2. The deceleration control method of electric friction hybrid brake power distribution for trains according to claim 1, further comprising, after transmitting the theoretical friction brake force to a train brake control system to collectively apply electric friction hybrid braking to trains by the train brake control system according to the theoretical friction brake force and by a subway vehicle traction control unit according to the theoretical maximum value of electric brake force:
acquiring the actual deceleration of the train in the braking process;
and performing proportional integral derivative control on the actual deceleration and the target deceleration to adjust the actual friction braking force output by the train brake control system until the absolute value of the difference between the actual deceleration and the target deceleration is not greater than a first preset threshold value or the iteration number of the proportional integral derivative control reaches a second preset threshold value.
3. The deceleration control method of electric friction hybrid brake power distribution for trains according to claim 2, characterized in that in the case where the number of iterations of the proportional-integral-derivative control reaches a second preset threshold value and the absolute value of the difference between the actual deceleration and the target deceleration is greater than a first preset threshold value, a new deceleration demand newly determined by the train automatic driving system is received;
and according to the new deceleration requirement, completing the electric friction hybrid braking of the train again.
4. The deceleration control method for electric friction hybrid brake power distribution of train according to claim 2, wherein said receiving theoretical maximum value of electric brake force transmitted by subway vehicle traction control unit to determine braking condition of train according to said theoretical maximum value of electric brake force and total brake force comprises:
determining the total braking force based on the deceleration demand to brake the train and the vehicle dynamic mass;
sending the total braking force to the metro vehicle traction control unit to obtain the theoretical maximum value of the electric braking force fed back by the metro vehicle traction control unit;
calculating the absolute value of the difference between the total braking force and the theoretical maximum value of the electric braking force;
and determining the braking working condition of the train according to the absolute value of the difference.
5. The method for controlling deceleration of electric friction hybrid brake power distribution of a train according to claim 4, wherein said determining the braking condition of the train according to the absolute value of the difference comprises:
determining the braking working condition of the train to be a full electric braking working condition under the condition that the absolute value of the difference value is smaller than the minimum value of the friction braking force which can be output by the train braking control system;
determining the braking working condition of the train to be a full electric braking working condition under the condition that the absolute value of the difference value is not less than the minimum value of the friction braking force which can be output by the train braking control system but less than a third preset threshold value;
and under the condition that the absolute value of the difference value is not less than the minimum value of the friction braking force which can be output by the train braking control system and is not less than a third preset threshold value, determining that the braking working condition of the train is an electric friction hybrid braking working condition.
6. The deceleration control method of electric friction hybrid brake power distribution for trains according to claim 5, characterized by, in the case where the absolute value of the difference is smaller than the minimum value of friction braking force that can be output by the train brake control system, further comprising:
controlling the subway vehicle traction control unit to reduce the theoretical maximum value of the electric braking force, so that a new difference absolute value determined by the reduced theoretical maximum value of the electric braking force is not less than the minimum value of the friction braking force which can be output by the train braking control system and is not less than a third preset threshold value;
and determining the braking working condition of the train as an electric friction hybrid braking working condition.
7. The deceleration control method of electric friction hybrid brake power distribution for trains according to claim 2, wherein performing proportional integral derivative control on the actual deceleration and a target deceleration to adjust the actual friction braking force output by the train brake control system until the absolute value of the difference between the actual deceleration and the target deceleration is not greater than a first preset threshold or the number of iterations of the proportional integral derivative control reaches a second preset threshold comprises:
acquiring the actual friction braking force corresponding to the actual deceleration and the theoretical friction braking force corresponding to the target deceleration to determine a friction braking force control value; the friction braking force control value is the absolute value of the difference between the theoretical friction braking force and the actual friction braking force;
determining a new theoretical friction braking force according to the actual deceleration, the target deceleration and the difference absolute value based on proportional integral derivative control;
according to the new theoretical friction braking force and the theoretical maximum value of the electric braking force, electric friction hybrid braking is carried out on the train together, and new actual deceleration is obtained again;
iteratively executing the acquiring of the actual friction braking force corresponding to the actual deceleration and the theoretical friction braking force corresponding to the target deceleration to re-determine a friction braking force control value until a new actual deceleration is acquired until an absolute value of a difference between the new actual deceleration and the target deceleration is not greater than a first preset threshold or the number of iterations of the proportional-integral-derivative control reaches a second preset threshold.
8. A deceleration control system for electric friction hybrid brake force distribution for a train, comprising:
the braking condition determining unit is used for receiving the theoretical maximum value of the electric braking force sent by the subway vehicle traction control unit so as to determine the braking condition of the train according to the theoretical maximum value of the electric braking force and the total braking force; the total braking force is determined according to a deceleration demand which is a train brake;
the friction braking force determining unit is used for determining theoretical friction braking force to be applied according to the difference value between the total braking force and the theoretical maximum value of the electric braking force under the condition that the braking working condition of the train is determined to be an electric friction mixed braking working condition;
and the hybrid brake control unit is used for sending the theoretical friction braking force to a train brake control system so as to jointly perform electric friction hybrid braking on the train by the train brake control system according to the theoretical friction braking force and by the subway vehicle traction control unit according to the theoretical maximum value of the electric braking force.
9. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the processor implements the deceleration control method steps of the train electric friction hybrid braking power distribution according to any one of claims 1 to 7 when executing the computer program.
10. A non-transitory computer readable storage medium having stored thereon a computer program, wherein the computer program when executed by a processor implements the deceleration control method steps of a train electric friction hybrid braking power distribution according to any one of claims 1 to 7.
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN114604211A (en) * | 2022-03-11 | 2022-06-10 | 中车株洲电力机车有限公司 | Urban rail vehicle and tread cleaning control method and system thereof |
CN114604210A (en) * | 2022-03-11 | 2022-06-10 | 中车株洲电力机车有限公司 | Double-heading vehicle and braking force control method suitable for double-heading operation of urban rail vehicle |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6457784B1 (en) * | 1998-03-12 | 2002-10-01 | Continental Teves Ag & Co., Ohg | Method and device for statically or dynamically determining set values concerning braking forces or braking torque |
JP2007131093A (en) * | 2005-11-09 | 2007-05-31 | Advics:Kk | Deceleration controller for vehicle |
JP2007203861A (en) * | 2006-02-01 | 2007-08-16 | Fuji Heavy Ind Ltd | Electric parking brake control device |
CN102689595A (en) * | 2011-04-06 | 2012-09-26 | 扬州亚星客车股份有限公司 | Control method of braking energy recovery system for pure-electric power city bus |
CN103754212A (en) * | 2014-01-08 | 2014-04-30 | 同济大学 | Method for controlling electric-hydraulic brake system on basis of differential gear train with two degrees of freedom |
CN106364333A (en) * | 2016-10-12 | 2017-02-01 | 南京中车浦镇海泰制动设备有限公司 | Brake control device for rail transit vehicle and electro-pneumatic hybrid braking control method of brake control device |
US20170096070A1 (en) * | 2015-10-06 | 2017-04-06 | Hyundai Motor Company | Method for controlling braking of regenerative braking co-operative control system for vehicle |
CN108081961A (en) * | 2017-11-30 | 2018-05-29 | 北京新能源汽车股份有限公司 | Braking energy recovery control method and device and electric automobile |
CN108099875A (en) * | 2017-12-12 | 2018-06-01 | 同济大学 | A kind of brake control method of rail vehicle adaptive friction coefficient |
CN111645651A (en) * | 2020-04-26 | 2020-09-11 | 摩登汽车(盐城)有限公司 | Braking torque distribution method of vehicle braking system |
CN112477831A (en) * | 2020-12-10 | 2021-03-12 | 交控科技股份有限公司 | Brake control system, method and railway vehicle |
-
2021
- 2021-05-07 CN CN202110495618.XA patent/CN113291280B/en active Active
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6457784B1 (en) * | 1998-03-12 | 2002-10-01 | Continental Teves Ag & Co., Ohg | Method and device for statically or dynamically determining set values concerning braking forces or braking torque |
JP2007131093A (en) * | 2005-11-09 | 2007-05-31 | Advics:Kk | Deceleration controller for vehicle |
JP2007203861A (en) * | 2006-02-01 | 2007-08-16 | Fuji Heavy Ind Ltd | Electric parking brake control device |
CN102689595A (en) * | 2011-04-06 | 2012-09-26 | 扬州亚星客车股份有限公司 | Control method of braking energy recovery system for pure-electric power city bus |
CN103754212A (en) * | 2014-01-08 | 2014-04-30 | 同济大学 | Method for controlling electric-hydraulic brake system on basis of differential gear train with two degrees of freedom |
US20170096070A1 (en) * | 2015-10-06 | 2017-04-06 | Hyundai Motor Company | Method for controlling braking of regenerative braking co-operative control system for vehicle |
CN106364333A (en) * | 2016-10-12 | 2017-02-01 | 南京中车浦镇海泰制动设备有限公司 | Brake control device for rail transit vehicle and electro-pneumatic hybrid braking control method of brake control device |
CN108081961A (en) * | 2017-11-30 | 2018-05-29 | 北京新能源汽车股份有限公司 | Braking energy recovery control method and device and electric automobile |
CN108099875A (en) * | 2017-12-12 | 2018-06-01 | 同济大学 | A kind of brake control method of rail vehicle adaptive friction coefficient |
CN111645651A (en) * | 2020-04-26 | 2020-09-11 | 摩登汽车(盐城)有限公司 | Braking torque distribution method of vehicle braking system |
CN112477831A (en) * | 2020-12-10 | 2021-03-12 | 交控科技股份有限公司 | Brake control system, method and railway vehicle |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN114604211A (en) * | 2022-03-11 | 2022-06-10 | 中车株洲电力机车有限公司 | Urban rail vehicle and tread cleaning control method and system thereof |
CN114604210A (en) * | 2022-03-11 | 2022-06-10 | 中车株洲电力机车有限公司 | Double-heading vehicle and braking force control method suitable for double-heading operation of urban rail vehicle |
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