Multi-power source locomotive control method and system

• US 7,944,081 B2
• Filed: 01/04/2010
• Issued: 05/17/2011
• Est. Priority Date: 01/24/2007
• Status: Active Grant

• Current Assignee: Railpower, LLC
• Original Assignee: Railpower, LLC
• Inventors: Wolff, Bruce, Donnelly, Frank Wegner, Watson, John David
• Primary Examiner(s): Fureman; Jared J
• Assistant Examiner(s): AMAYA, CARLOS DAVID
• Application Number:
  US12/651,613
• Publication Number:
  US 20100106343A1
• Time in Patent Office: 498 Days
• Field of Search: 307/9.1, 307/10.1, 307/43, 307/71, 307/80, 307/85
• US Class Current: 307/9.1
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 1/02 to electric heating circuits
• CPC Class Codes: B60L 15/32 Control or regulation of multiple-unit electrically-propelled vehicles
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 2210/30 AC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2220/12 Induction machines
• CPC Class Codes: B60L 2220/14 Synchronous machines
• CPC Class Codes: B60L 2220/16 DC brushless machines
• CPC Class Codes: B60L 2220/18 Reluctance machines
• CPC Class Codes: B60L 2220/20 DC electrical machines
• CPC Class Codes: B60L 2240/441 Speed
• CPC Class Codes: B60L 2240/443 Torque
• CPC Class Codes: B60L 2240/445 Temperature
• CPC Class Codes: B60L 2260/165 of converters
• CPC Class Codes: B60L 2260/26 Transition between different drive modes
• CPC Class Codes: B60L 2270/142 acoustic
• CPC Class Codes: B60L 50/12 using AC generators and DC motors
• CPC Class Codes: B60L 50/13 using AC generators and AC motors
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B60L 50/52 : characterised by DC-motors
• CPC Class Codes: B60L 50/53 : in combination with an external power supply, e.g. from overhead contact lines
• CPC Class Codes: B60L 50/61 : by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 7/12 : for vehicles propelled by dc motors
• CPC Class Codes: B60L 7/14 : for vehicles propelled by ac motors
• CPC Class Codes: B60L 7/22 : Dynamic electric resistor braking, combined with dynamic electric regenerative braking
• CPC Class Codes: B61C 7/04 : Locomotives or motor railcars with two or more different kinds or types of engines, e.g. steam and IC engines
• CPC Class Codes: H02J 1/10 : Parallel operation of dc sources
• CPC Class Codes: H02J 1/14 : Balancing the load in a network
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 10/92 : Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles
• CPC Class Codes: Y02T 30/00 : Transportation of goods or passengers via railways, e.g. energy recovery or reducing air resistance

Abstract

Control modes for operating multiple power sources include energy storage systems and applicable to large systems such as locomotives. Selectable operating modes are provided for different locomotive speed ranges and work loads. A common DC bus electrical architecture is used so that prime power sources need not be synchronized. Multiple-engine locomotives have the engine systems that may be electrically connected in parallel or in series or in combinations of parallel and series to a DC bus.

Claims

1. A method of controlling a desired total system output power from a locomotive comprising a plurality of power sources, the plurality of power sources outputting DC electrical power in parallel to a common DC bus, and said vehicle also comprising a variable power control having a plurality of power settings, said method comprising the steps of:

a) selecting a number of power sources to be used according to a schedule to provide power in parallel to the DC common bus;

b) activating the power sources according to said schedule;

c) setting a desired range of a parameter indicative of power available on the DC common bus from at least one of voltage or current on the DC common bus;

d) measuring a signal corresponding to the parameter indicative of power available on the DC common bus from at least one of voltage or current on the DC common bus;

e) for each of the plurality of power sources, measuring a signal indicative of a power source operational parameter from said each of the plurality of power sources;

f) determining an output power for each of the plurality of power sources, based on the measurement of the signal indicative of the power source operational parameter from said each of the plurality of power sources and the signal corresponding to the parameter indicative of at least one of voltage or current on the DC common bus; and

g) if the output power of one of the plurality of power sources is different from a target output power, adjusting a power source control parameter of said one of the plurality of power sources to correct the difference.

2. The method according to claim 1, wherein the power source operational parameter comprises at least one of current, voltage, torque, speed and fuel injection rate.

3. The method according to claim 1, wherein the parameter indicative of the power available on the DC common bus is the DC common bus voltage, and the signal indicative of the power source operational parameter is at least one of current, voltage, torque, speed and fuel injection rate from said each of the plurality of power sources.

4. The method according to claim 1, wherein all selected power sources in step a) operate at a same power level.

5. The method according to claim 1, wherein all selected power sources but one in step a) operate at a same power level, said one power source operating at a different power level and enabling the all selected power sources but one to optimize an operating parameter.

6. The method of claim 5, wherein said operating parameter is selected from the group consisting of (i) fuel efficiency;

(ii) low emissions;

(iii) noise level;

(iv) power;

(v) tractive effort;

(vi) engine lifetime, (vii) location of the vehicle and (viii) any combination thereof.

7. The method according to claim 1, wherein each power setting corresponds to a power level which is obtained by adding another power source as soon as the currently operating power sources reach a selected percentage of their rated power.

8. The method according to claim 1, wherein an operator of the vehicle manually selects at least one of the number of power sources to be used according to the schedule and an operating parameter of one of the number of power sources to be used according to the schedule, said operating parameter being selected from the group consisting of (i) fuel efficiency;

(ii) low emissions;

(iii) noise level;

(iv) power;

(v) tractive effort;

(vi) engine lifetime, (vii) location of the vehicle, (viii) maximum engine output power, (ix) engine speed and (x) any combination thereof.

9. The method according to claim 5, wherein said number of power sources to be used and the power and engine speed setting for each power source are selected in order to obtain a desired fuel efficiency for that power setting and are determined using a controller programmed to use fuel consumption maps for each power source.

10. The method according to claim 5, wherein said number of power sources to be used and the power and engine speed setting for each power source in order to obtain the desired emissions for that power setting are determined using a controller programmed to use an emissions map for each power source.

11. The method according to claim 1, wherein said plurality of power sources comprise a plurality of prime movers and one or more energy storage systems.

12. The method according to claim 1, wherein said variable power control having a plurality of power settings comprises one or more idle settings and a plurality of power notch settings.

13. The method according to claim 1, wherein step a) comprises the steps of:

i) determining a specified output power for a selected notch setting and vehicle speed;

ii) selecting an optimum power source operating mode;

iii) selecting a number of power sources required to provide the specified output power for the selected notch setting and vehicle speed;

iv) selecting specific power sources to provide the specified output power for the selected notch setting and vehicle speed;

v) verifying whether any of the selected specific power sources need to be derated;

vi) if a power source from any of the selected specific power sources needs to be derated,

derating said power source needing derating and returning to step iii); and

vii) if a power source from the plurality of power sources is not required to provide the specified output power for the selected notch setting and vehicle speed, deactivating said non-required power source.

14. The method according to claim 13, wherein the vehicle is operating in dynamic braking mode and further comprising, prior to step a), the steps of:

aa) selecting a dynamic braking power level;

bb) determining if dynamic braking available power is sufficient for providing the desired total system output power;

cc) if the dynamic braking available power is sufficient for providing the desired total system output power, performing step g) wherein the desired total system output power comprises output power from dynamic braking; and

dd) if the dynamic braking available power is not sufficient for providing the desired total system output power, performing step a) wherein the desired total system output power comprises output power from dynamic braking and output power from the plurality of power sources.

15. The method according to claim 1, further comprising a step of deactivating a selected one of the plurality of power sources, said deactivating step comprising the steps of:

I) selecting between an idle mode and a shutdown mode;

II) if the idle mode is selected, performing the steps of;

A. selecting between a high idle power level and a low idle power level;

B. setting an excitation current for the selected deactivating power source such that an output voltage of the selected deactivating power source is below a DC common bus voltage;

C. selecting an optimum operating mode for the selected deactivating power source; and

D. adjusting the excitation current for the selected deactivating power source such that the output voltage of the selected deactivating power source is below a DC common bus voltage and the selected deactivating power source achieves said optimum operating mode; and

III) if the shutdown mode is selected, performing the steps of;

E. from look-ahead data, determining if the power source can be turned off;

F. if a time required to shutdown the power source is below a threshold, performing steps II) A through II) D; and

G. if the time required to shutdown the power source is above the threshold, turning off the engine.

16. The method according to claim 1, wherein step b) comprises the steps of:

I) if the power sources are off, preheating the power sources;

II) turning on lubricating oil flow;

III) starting the power sources;

IV) selecting between a high idle power level and a low idle power level;

V) setting an excitation current for the selected activating power source such that an output voltage of the selected activating power source is below a DC common bus voltage

VI) selecting an optimum operating mode for the selected activating power source; and

VII) adjusting the excitation current for the selected activating power source such that the output voltage of the selected deactivating power source is below a DC common bus voltage and the selected activating power source achieves said optimum operating mode.

17. A system for controlling a desired total system output power from a locomotive comprising a plurality of power sources, the plurality of power sources outputting DC electrical power in parallel to a common DC bus, and said vehicle also comprising a variable power control having a plurality of power settings, the control system comprising:

selecting means for selecting a number of power sources to be used according to a schedule to provide power to the DC common bus;

activating means for activating the power sources according to said schedule;

setting means for setting a desired range of a parameter indicative of power available on the DC common bus from at least one of voltage or current on the DC common bus;

first measuring means for measuring a signal corresponding to the parameter indicative of power available on the DC common bus from at least one of voltage or current on the DC common bus;

second measuring means, for each of the plurality of power sources, for measuring a signal indicative of a power source operational parameter from said each of the plurality of power sources;

determining means for determining an output power for each of the plurality of power sources, based on the measurement of the signal indicative of the power source operational parameter from said each of the plurality of power sources and the signal corresponding to the parameter indicative of at least one of voltage or current on the DC common bus; and

adjusting means for adjusting a power source control parameter of said one of the plurality of power sources to correct a difference between the output power of one of the plurality of power sources and a target output power.

18. The system according to claim 17, wherein the power source operational parameter comprises at least one of current, voltage, torque, speed and fuel injection rate.

19. The system according to claim 17, wherein the parameter indicative of the power available on the DC common bus is the DC common bus voltage, and the signal indicative of the power source operational parameter is at least one of current, voltage, torque, speed and fuel injection rate from said each of the plurality of power sources.

20. The system according to claim 19, wherein the system further comprises an energy storage system and an auxiliary power system connected to the DC common bus and wherein each of the plurality of power sources comprises an output shaft connected to a mechanical transmission driving a plurality of traction motor propulsion systems.