Method and system for increasing efficiency of rolling stock

Abstract

The invention is intended for conserving energy expended by railway rolling stock, for instance by a locomotive when carrying out train operations and shunting, when trains are run in an automatic mode or in a train operator assistance mode. A method for increasing the efficiency of rolling stock includes the following steps: obtaining the parameters of the rolling stock, including at least the following: speed, coordinates, overhead system voltage, traction engine current voltage, brake line discharging; in addition, determining at least the dependence parameters of an active traction force, braking force, motion resistance force, force of wheel adherence to the rails, and the mass of the rolling stock; then, determining the optimal control to be carried out by traction and braking equipment of railway rolling stock based on the dependence parameters obtained during the previous step; then, transmitting the optimal control, determined during the previous step, to a rolling stock control system for implementation or for displaying to the train operator.

Claims

1. A method of enhancing performance of a train, the method comprising: receiving data indicative of train parameters for a train the train parameters comprising speed of the train, coordinates of the train, traction drive voltage of the train, traction engine currents of the train, and brake discharging value of the train; determining dependency parameters for the train at least in part based on the data indicative of the train parameters, the dependency parameters comprising effective traction force of the train, braking force of the train, resistance to movement force of the train, and wheel-to-rail traction force of the train; determining mass of the train; determining control data for the train based on the dependency parameters, wherein the control data corresponds to minimum energy expenditure to operate the train; and causing a train control system to control traction and braking equipment of the train based on the control data to enhance performance of the train by minimizing energy expenditure for operating the train, wherein the method is performed by a controller.

2. A method according to claim 1, wherein receiving the train parameters for the train, determining the dependency parameters for the train and determining the control data for the train are cyclically performed.

3. A method according to claim 1, wherein the coordinates of the train and the speed of the train are determined using a navigation system.

4. A method according to claim 3, wherein the navigation system comprises a Global Positioning System (GPS) or Glonass.

5. A method according to claim 1, wherein the coordinates of the train and the speed of the train are determined using an odometric sensor.

6. A method according to claim 2, wherein the mass of the train is determined based on data from a previous cycle, the previous cycle data associated with previously determined resistance to movement force of the train, effective traction force of the train, and braking force of the train.

7. A method according to claim 2, wherein the mass of the train and at least some of the dependency parameters are determined based on data from a previous cycle, the previous cycle data associated with previously receiving the train parameters for the train, determining the dependency parameters for the train, and determining the control data for the train.

8. A method according to claim 1, wherein the mass of the train is determined using probability statistical information.

9. A method according to claim 8, wherein the probability statistical information comprises statistical expectation and covariance matrix of estimated parameters and covariance matrix of measuring errors.

10. A method according to claim 8, wherein the probability statistical information comprises statistical expectation and correlation matrix of estimated parameters and correlation matrix of measuring errors.

11. A system for enhancing performance of a train, the system comprising: a data storage device that stores instructions; and a controller in communication with the data storage device, the controller configured to execute the instructions that cause the controller to: receive data indicative of train parameters for a train the train parameters comprising speed of the train, coordinates of the train, traction drive voltage of the train, traction engine currents of the train, and brake discharging value of the train; determine dependency parameters for the train at least in part based on the data indicative of the train parameters, the dependency parameters comprising effective traction force of the train, braking force of the train, resistance to movement force of the train, and wheel-to-rail traction force of the train; determine mass of the train; determine control data for the train, based on dependency parameters, wherein the control data corresponds to minimum energy expenditure to operate the train; and communicate the control data to a train control system configured to control traction and braking equipment of the train based on the control data to enhance performance of the train by minimizing energy expenditure for operating the train.

12. A system according to claim 11, wherein the controller is configured to cyclically determine the dependency parameters for the train and determine the control data for the train.

13. A system according to claim 11, further comprising a navigation system configured to determine the coordinates of the train and the speed of the train.

14. A system according to claim 13, wherein the navigation system comprises Global Positioning System (GPS) or Glonass.

15. A system according to claim 11, further comprising an odometric sensor configured to determine at least one of the speed of the train or the coordinates of the train.

16. A system according to claim 12, wherein the mass of the train is determined based on data from a previous cycle, the previous cycle data associated with previously determined resistance to movement force of the train, effective traction force of the train, and braking force of the train.

17. A system according to claim 12, wherein the mass of the train and at least some of the dependency parameters are determined based on data from a previous cycle, the previous cycle data associated with previously receiving the train parameters for the train, determining the dependency parameters for the train, and determining the control data for the train.

18. A system according to claim 11, wherein the mass of the train is determined using probability statistical information.

19. A system according to claim 18, wherein the probability statistical information comprises statistical expectation and correlation matrix of estimated parameters and correlation matrix of measuring errors.

20. A system according to claim 18, wherein the probability statistical information comprises statistical expectation and covariance matrix of estimated parameters and covariance matrix of measuring errors.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a diagram illustrating a method for enhancing performance of a train by minimizing energy expenditure for operating the train.

(2) FIG. 2 illustrates a system for enhancing performance of a train by minimizing energy expenditure for operating the train.

DETAILED DESCRIPTION OF THE INVENTION

(3) This invention proposed in several embodiments may be implemented as a method realized with a computer, as a system or a computer-readable medium containing instructions for implementation of the above method.

(4) In certain embodiments, the invention may be implemented as a distributed computer system.

(5) For the purposes of this invention, a system is a computer system, ECM (electronic computing machine), PNC (programmed numerical control), PLC (programmed logic controller), computerized control systems and any other devices capable to perform a set well defined sequence of operations (actions, instructions).

(6) An instruction-processing device is an electronic unit or an integrated circuit (a microprocessor) performing computer instructions (programs).

(7) The instruction-processing device reads computer instructions (programs) from one or more data storage devices and executes them. Data storage devices may include but are not limited to, hard disc drives (HDDs), flash memory drives, ROM (read-only memory), solid-state drives (SSD) or optical drives.

(8) A program is a succession of instructions designed to be executed by a control device of a computer or by an instruction-processing device.

(9) In the invention, energy-saving effect is achieved by estimation and application of traction force and braking force by a locomotive-driven train for the distance of s.sub.k-s.sub.0 during the time T and compliance of safety requirements including, without limitation, speed limits and locomotive warning system's indications, so that energy used by a locomotive for train operation will be minimal:

(10) $\begin{array}{cc}A={}_{s_0}^{s_k}Fds.fwdarw.\min & \left(1\right)\\ \mathrm{where}\text{:}& \\ M\left(\frac{1+}{}\right)\frac{dv}{dt}=F--W\left(v,x\right)-B\left(p,v,t_p\right),& \end{array}$
M is the weight of the train, t;
v is the speed, m/s;
F is the traction effort or braking effort of a traction drive equipped with energy recuperation system, kN;
is the braking effort of a traction drive not equipped with energy recuperation system, kN;
W is total resistance to movement, kN;
B is the pneumatic (electro-pneumatic) braking effort, kN;
is the converting factor, which depends on measurement units used in calculation;
p is brake discharging value, kPa;
x is the current coordinate;
is the inertia factor;
t.sub.p is the time elapsed from the moment of application of pneumatic brakes.

(11) To calculate energy-optimal traction effort F, current values of the following dependencies need to be known: total resistance to movement of the railway train; wheel-to-rail traction force; traction force of the locomotive-driven train; braking force of the locomotive-driven train.

(12) Besides, values of maximum and minimum traction effort determined using technical specifications of the locomotive-driven train are required.

(13) The term dependency value shall mean such a value p (p is dimension vector n) that for each pair of values x, y of the expression y=f(x,p)

(14) and for every i=1,n it follows that p.sub.1=const (depends on neither x nor on y).

(15) The method of enhancing efficiency of train according to the invention involves the following steps:

(16) train parameters are obtained, which include at least the following:

(17) speed, coordinates, traction drive voltage, traction engine currents, brake discharging value;
the train's speed and coordinates may be determined on the basis of, without limitation, sensor indications or by using radio positioning facilities, e.g. GPS of Glonass.

(18) Dependency values of effective traction effort are determined, based on which effective traction effort is determined;

(19) Dependency of actual (effective) traction effort on measured parameters, e.g., for a locomotive with commutator motors may be represented as follows:
F.sub.=(v,l,U),(2)
where v is the locomotive-driven train's movement speed;
l is the current flowing through armature circuit of traction engines of the locomotive-driven train;
U is the current at armature winding of traction engines of the locomotive-driven train.

(20) Henceforth in the invention, analytical dependency factors may be calculated using, without limitation, Kalman filtering method. Dependency type and used method of factor calculation are not essential for the invention.

(21) The calculated traction effort of the locomotive is limited by minimum and maximum forces, which may technically be realized by a traction drive to a locomotive-driven train
F.sub.min<F<F.sub.max(3)

(22) According to one embodiment, minimum and maximum traction effort are inputted at configuration and adjustment stage.

(23) In some embodiments, minimum and maximum traction effort are inputted by driver through a man-machine interface.

(24) The weight of the train is determined;

(25) The weight of the train is determined by using the expression (1) analytically, it should be noted that in some embodiments to determine the weight of the train values, one or several of the stated parameters (M, F, F.sub., W, B) may be required.

(26) In some embodiments, parameters necessary to calculate the weight of the train are determined with the use of a priori information including at least statistical expectation, covariance matrix of the estimated parameters and covariance matrix of measuring errors.

(27) In some of the embodiments of the invention, at least total resistance to movement and braking effort necessary to estimate the weight of the train are determined on the basis of data obtained during previous cycle of calculation.

(28) Method of calculation of the weight of the train is not essential for the invention and may vary.

(29) Dependency values of effective braking effort are determined, based on which effective braking effort is determined;

(30) Braking effort B may be represented by the following analytical dependency:
B=(p,v,t.sub.p),(4)
where is the analytical dependency establishing a relation between brake discharging value and braking force B.
p is brake discharging value, kPa;
v is the speed, m/s;
t.sub.p is the time elapsed from the moment of application of pneumatic braking.

(31) Resistance to movement dependency values are determined, on the basis of which total resistance to movement is determined;

(32) Total resistance to movement is determined by main and additional resistance to movement, which may include at least resistance to movement occurring due to plan and profile of railway i:
WM.Math.(i(x)+a.sub.w+b.sub.wv+c.sub.wv.sup.2),(5)
where a.sub.w,b.sub.w,c.sub.w are dependency factors;
M is the weight of the train, t;
v is the speed, m/s;
i(x) is specific resistance to movement due to plan and profile of railway,

(33) Traction factor dependency values are determined, on the basis of which actual traction factor is determined;

(34) Wheel-to track traction force F.sub.adh may be represented by the following analytical dependency:
FF.sub.adh=a.sub.adh+b.sub.adhv+c.sub.adhv.sup.2(6)

(35) Where a.sub.adh,b.sub.adh,c.sub.adh are dependency parameters requiring calculation;

(36) v is the locomotive-driven train's movement speed;

(37) Apparently, the train's traction effort F cannot exceed traction force. F.sub.adh

(38) With the use of the data calculated at the previous steps, current and estimated optimal control input is determined, which includes traction effort or braking effort.

(39) With dependency (2), (4), (5) and (6) values and the train's weight known, traction effort is calculated to ensure minimum energy expenditure.

(40) $A={}_{s_0}^{s_k}Fds.fwdarw.\min$

(41) The optimal value of a locomotive-driven train's power input value is related to the control system of the locomotive-driven train for execution, or for display to the operator.

(42) It will be readily understood by those skilled in the art that specific embodiments of the method and the system for enhancing efficiency of a train are described here as mere examples and that various modifications are possible, which lie within the spirit and scope of the invention.