POWER SYSTEM AND METHOD FOR DRIVING AN ELECTROMOTIVE TRACTION SYSTEM AND AUXILIARY EQUIPMENT THROUGH A COMMON POWER BUS

• US 20100148581A1
• Filed: 12/12/2008
• Published: 06/17/2010
• Est. Priority Date: 12/12/2008
• Status: Active Grant

• Current Assignee: GE Global Sourcing LLC (Westinghouse Air Brake Technologies Corporation)
• Original Assignee: General Electric Company
• Inventors: Kumar, Ajith Kuttannair, Worden, Bret Dwayne, Gupta, Sudhir Kumar, Nikolov, Emil, Daigle, Jeffrey Louis, Ioannidis, Dimitrios
• Granted Patent: US 7,928,597 B2
• Time in Patent Office: Days
• US Class Current: 307/30
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 2270/147 electro magnetic [EMI]
• CPC Class Codes: B60L 9/005 Interference suppression
• CPC Class Codes: H03H 1/0007 of radio frequency interference filters

Abstract

Power system and method for providing electrical power are provided. The system includes a traction system and auxiliary equipment coupled to a power bus. The traction system includes one or more electromotive machines having a first type of stator winding that provides protection relative to voltage spikes expected at the traction stator under a first voltage level appropriate for the traction system. The auxiliary equipment includes one or more electromotive machines having a second type of stator winding that provides protection relative to spikes expected at the auxiliary stator under a second voltage level lower than the first voltage level. Inverter circuitry is coupled to drive the auxiliary equipment, and signal-conditioning circuitry is provided to attenuate voltage spikes produced by the inverter circuitry. The power bus is operated at the first voltage level, and the voltage spike attenuation is sufficient to protect the auxiliary stator.

Claims

1. A power system comprising:

a power source;

a power bus coupled to receive electrical power from the power source;

a traction system coupled to the power bus, wherein the traction system comprises at least one electromotive machine having a first type of stator winding configured to provide a level of protection relative to voltage spikes expected at the traction stator under a first voltage level appropriate for the traction system;

auxiliary equipment coupled to the power bus, wherein the auxiliary equipment comprises at least one electromotive machine having a second type of stator winding configured to provide a level of protection relative to voltage spikes expected at the auxiliary stator under a second voltage level, wherein the second voltage level is lower than the first voltage level;

inverter circuitry coupled to drive the auxiliary equipment; and

signal-conditioning circuitry coupled to attenuate repetitive voltage spikes produced by the inverter circuitry, wherein the power bus is operated at the first voltage level, and further wherein the voltage spike attenuation is sufficient to protect the auxiliary stator notwithstanding of operation of the power bus at the first voltage level.

2. The power system of claim 1, wherein the auxiliary stator winding comprises random-wound windings and the traction stator winding comprises form-wound windings.

3. The power system of claim 1, wherein the signal-conditioning circuitry comprises a filter.

4. The power system of claim 3, wherein the filter comprises a resistor/inductor/capacitor-based filter arranged in a Y-circuit topology, wherein each branch of the Y-circuit comprises a respective resistor, inductor and capacitor connected in series circuit.

5. The power system of claim 4, wherein a line separation from an output side of a given inverter circuitry to an input side of a given auxiliary load comprises a first distance, and further wherein said filter is located in a range from the output side of the inverter circuitry to a second distance downstream from the inverter circuitry, wherein the second distance is half the first distance.

6. The power system of claim 4, wherein a value of a reactance of the filter is based, at least in part, on a reactance of a load presented by the auxiliary equipment and an intrinsic reactance of a connecting line.

7. The power system of claim 3, wherein the filter comprises a resistor/capacitor-based low-pass filter.

8. The power system of claim 7, wherein said filter is arranged in a Y-circuit topology or in a delta-circuit topology.

9. The power system of claim 7, wherein said filter is further based on inductance and is arranged in a Y-circuit topology, wherein each branch of the Y-circuit comprises a respective resistor and inductor connected in parallel circuit and further comprises a capacitor connected in series circuit to the parallel circuit.

10. The power system of claim 9, wherein a line separation from an output side of a given inverter circuitry to an input side of a given auxiliary load comprises a first distance, and further wherein said filter is located in a range from the input side of the auxiliary load to a second distance upstream from the auxiliary load, wherein the second distance is half the first distance.

11. The power system of claim 7, wherein a line separation from an output side of a given inverter circuitry to an input side of a given auxiliary load comprises a first distance, and further wherein said filter is located in a range from the input side of the auxiliary load to a second distance upstream from the auxiliary load, wherein the second distance is half the first distance.

12. The power system of claim 7, wherein a value of a reactance of the filter is based, at least in part, on a reactance of a load presented by the auxiliary equipment and an intrinsic reactance of a connecting line.

13. The power system of claim 1, wherein the signal-conditioning circuitry comprises at least one line interconnecting the inverter circuitry and the auxiliary equipment and wherein the attenuation of the voltage spikes is based on an impedance match between the auxiliary equipment and the interconnecting line.

14. The power system of claim 1, wherein the power system comprises a locomotive power system.

15. A method for arranging and operating a powered system comprising:

coupling a power bus to receive electrical power from a power source;

coupling a traction system to the power bus, wherein the traction system comprises at least one electromotive machine having a first type of stator winding configured to provide a level of protection relative to voltage spikes expected at the traction stator under a first voltage level appropriate for the traction system;

coupling auxiliary equipment to the power bus wherein the auxiliary equipment comprises at least one electromotive machine having a second type of stator winding configured to provide a level of protection relative to voltage spikes expected at the auxiliary stator under a second voltage level, wherein the second voltage level is lower than the first voltage level;

coupling inverter circuitry to drive the auxiliary equipment;

operating the power bus at the first voltage level; and

conditioning signals from the inverter circuitry to the auxiliary equipment to attenuate voltage spikes produced by the inverter circuitry, wherein the voltage spike attenuation is sufficient to protect the auxiliary stator notwithstanding of operating the power bus at the first voltage level.

16. The method of claim 15, wherein the signal conditioning comprises establishing an impedance match between the auxiliary equipment and at least one line interconnecting the inverter circuitry and the auxiliary equipment.

17. The method of claim 15, wherein the signal conditioning comprises filtering the signals from the inverter circuitry to the auxiliary equipment.

18. The method of claim 17, wherein a line separation from an output side of a given inverter circuitry to an input side of a given auxiliary load comprises a first distance, and wherein the method further comprises defining a first filter topology to be located in a range from the output side of the inverter circuitry to a second distance downstream from the inverter circuitry, wherein the second distance is half the first distance.

19. The method of claim 18, wherein the method further comprises defining a second filter topology to be located in a range from the input side of the auxiliary load to a distance upstream from the auxiliary load, wherein the distance upstream from the auxiliary load is half the first distance.

20. The method of claim 15, wherein the signal conditioning comprises adjusting a switching speed of a power switching device in the inverter circuitry.

21. The method of claim 20, wherein the adjusting of the switching speed comprises reducing the switching speed as a function of cable length and a desired level of voltage spike suppression at the input side of the auxiliary load.

22. The method of claim 15, wherein the signal conditioning comprises a combination of at least two of the following:

filtering the signals from the inverter circuitry to the auxiliary equipment;

establishing an impedance match between the auxiliary equipment and at least one line interconnecting the inverter circuitry and the auxiliary equipment; and

adjusting a switching speed of a power switching device in the inverter circuitry.

23. A method for providing electrical power in a powered system, the method comprising:

operating a power bus at a first voltage level, wherein the power bus receives electrical power from a power source;

drawing power from the power bus at a traction system, wherein the traction system comprises at least one electromotive machine having a first type of stator winding configured to provide a level of protection relative to voltage spikes expected at the traction stator under the first voltage level;

drawing power from the power bus through inverter circuitry connected to the bus, said power being drawn by auxiliary equipment comprising at least one electromotive machine having a second type of stator winding configured to provide a level of protection relative to voltage spikes expected at the auxiliary stator under a second voltage level, and wherein the second voltage level is lower than the first voltage level; and

conditioning the power drawn through the inverter circuitry to attenuate voltage spikes produced by the inverter circuitry, wherein the voltage spike attenuation is sufficient to protect the auxiliary stator notwithstanding of operating the power bus at the first voltage level.