Hybrid energy off highway vehicle propulsion circuit

• US 20050005814A1
• Filed: 08/09/2004
• Published: 01/13/2005
• Est. Priority Date: 03/27/2001
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Young, Henry Todd, Kumar, Ajith Kuttannair
• Granted Patent: US 7,185,591 B2
• Time in Patent Office: Days
• US Class Current: 105/35
• CPC Class Codes: B60K 6/28 characterised by the electric energy storing means, e.g. batteries or capacitors
• CPC Class Codes: B60K 6/44 Series-parallel type
• CPC Class Codes: B60K 6/46 Series type
• CPC Class Codes: B60L 15/2045 for optimising the use of energy
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 2200/40 Working vehicles
• 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 2260/28 Four wheel or all wheel drive
• CPC Class Codes: B60L 2270/20 Inrush current reduction, i.e. avoiding high currents when connecting the battery
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 50/15 with additional electric power supply with capacitors charged by engine-driven generators B60L50/40; with batteries charged by engine-driven generators B60L50/61
• CPC Class Codes: B60L 50/30 using propulsion power stored mechanically, e.g. in fly-wheels
• CPC Class Codes: B60L 50/40 using propulsion power supplied by capacitors
• CPC Class Codes: B60L 50/51 characterised by AC-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 58/40 for controlling a combination of batteries and fuel cells
• CPC Class Codes: B60L 7/02 Dynamic electric resistor braking B60L7/22 takes precedence
• CPC Class Codes: B60L 7/06 : for vehicles propelled by ac 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: B60L 9/00 : Electric propulsion with power supply external to the vehicle electric propulsion for monorail vehicles, suspension vehicles or rack railways B60L13/00; in combination with batteries or fuel cells within the vehicle B60L50/53
• CPC Class Codes: B60W 10/26 : for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60Y 2200/14 : Trucks; Load vehicles, Busses
• CPC Class Codes: B60Y 2304/076 : by add-on parts, e.g. retrofit
• CPC Class Codes: E21F 17/06 : Distributing electric power; Cable networks; Conduits for cables circuit arrangements for supplying or distributing electric power in general H02J
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility

Abstract

A system and method for retrofitting a propulsion circuit of an existing Off Highway Vehicle to enable the propulsion circuit to operate as a hybrid energy Off Highway Vehicle propulsion circuit. The hybrid propulsion circuit includes a primary power source, and a traction motor for preopelling an Off Highway Vehicle in response to the primary electric power. The traction motor has a motoring mode of operation and a power dissipation mode of operation. The traction motor generates dynamic braking electrical power in the power dissipation mode of operation. An electrical energy storage system includes a chopper circuit coupled to an energy storage device. The storage device is responsive to the chopper circuit to selectively store electrical energy generated in the power dissipation mode. The storage system selectively provides secondary electric power from the storage device to traction motor to assist in propelling the Off Highway Vehicle during the motoring mode.

Claims

1. A retrofit system for combining with a propulsion circuit of an existing Off Highway Vehicle to enable the propulsion circuit to operate as a hybrid energy Off Highway Vehicle propulsion circuit, said existing propulsion circuit having a power converter driven by an engine providing primary electric power, a traction bus coupled to the power converter for carrying the primary electric power, at least one traction motor receiving the primary electric power, said traction motor having a motoring mode of operation and a power dissipation mode of operation, wherein said traction motor rotates at least one wheel of the vehicle for propelling an Off Highway Vehicle in response to electric power received at the traction motor during the motoring mode, and wherein said traction motor generates dynamic braking electrical power which is returned to the traction bus and dissipated when the traction motor is operating in its power dissipation mode, an electrical resistance system for dissipating electric power generated in the traction motor during the power dissipation mode, said electrical resistance system including at least two resistor grid circuits, the retrofit system comprising:

an electrical energy storage system electrically connected to the traction bus and replacing one of the two resistor grid circuits, said energy storage system including an energy storage device for capturing electrical energy generated by the traction motor in the power dissipation mode.

2. The retrofit system of claim 1 wherein the electrical resistance system includes a first electrical resistance grid in a circuit having a two-position switch that is closed during the power dissipation mode and open during the motoring mode for dissipating an amount of power determined by the traction bus voltage when the traction motor is operating in the power dissipation mode, and wherein the electrical energy storage system includes a variably controlled electrical switch to regulate power storage in the electrical energy storage system and maintain the direct current bus voltage at a desired voltage magnitude when the traction motor is operating in the dissipation mode.

3. The retrofit system of claim 1 wherein the electrical energy storage system comprises:

a first storage device coupled to the traction bus for storing electrical power;

a first auxiliary switching device responsive to dynamic braking electric power generated in the traction motor during the power dissipation mode for selectively transmitting a first portion of the dynamic braking electrical power to the energy storage device for storage as secondary power.

4. The retrofit system of claim 3 wherein secondary power is selectively transmitted from the first storage device to the traction motor when the traction motor is operating in motoring mode to augment the primary electric power and assist in propelling the Off Highway Vehicle.

5. The retrofit system of claim 3 wherein the electrical energy storage system further comprises:

a second storage device coupled to the traction bus for storing electrical power; and

a second auxiliary switching device responsive to dynamic braking electric power generated in the traction motor during the power dissipation mode for selectively transmitting a second portion of the dynamic braking electrical power to the second storage device as secondary power.

6. The retrofit system of claim 5 wherein secondary power is selectively transmitted from the second storage device to the traction motor when the traction motor is operating in motoring mode to augment the primary electric power and assist in propelling the Off Highway Vehicle.

7. The retrofit system of claim 1 wherein the Off Highway Vehicle travels along an inclined load haulage road, and wherein the energy storage system is carried on the vehicle and transfers captured electrical energy to the traction motor to assist in propelling the off highway vehicle during motoring mode and captures electrical energy in the energy storage system generated when the traction motors transiently generate power due to bumps and other rough ground encountered on the haulage road while operating in motoring mode.

8. The retrofit system of claim 7 wherein the Off Highway Vehicle travels uphill and downhill on the inclined load haulage road, and wherein the energy storage system transfers captured electrical energy to the traction motor during the uphill travel of the vehicle and captures dynamic braking electrical energy in the energy storage system generated in the power dissipation mode during the downhill travel of the vehicle.

9. The retrofit system of claim 7 wherein substantially all of the captured electrical energy is available for use in the propulsion of the Off Highway Vehicle over the road.

10. The retrofit system of claim 1 wherein the energy storage system comprises a battery system.

11. The retrofit system of claim 1 wherein the energy storage system comprises a flywheel system.

12. The retrofit system of claim 1 wherein the energy storage system comprises an ultra-capacitor.

13. A retrofit system for combining with a propulsion circuit of an existing Off Highway Vehicle to enable the propulsion circuit to operate as a hybrid energy Off Highway Vehicle propulsion circuit, said existing propulsion circuit having a power converter driven by an engine providing primary electric power, a traction bus coupled to the power converter for carrying the primary electric power, at least one traction motor receiving the primary electric power, said traction motor having a motoring mode of operation and a power dissipation mode of operation, wherein said traction motor rotates at least one wheel of the vehicle for propelling an Off Highway Vehicle in response to electric power received at the traction motor during the motoring mode, and wherein said traction motor generates dynamic braking electrical power which is returned to the traction bus and dissipated when the traction motor is operating in its power dissipation mode, an electrical resistance system for dissipating electric power generated in the traction motor during the power dissipation mode, said electrical resistance system including at least two resistor grid circuits, said system comprising:

an electrical energy storage system coupled to the traction bus in addition to the two resistor grid circuits, said energy storage system including an electrical power storage device for storing dynamic braking electrical power generated by the traction motor in the power dissipation mode as secondary electrical power, and for transmitting stored secondary electrical power from the storage device to the traction motor to augment the primary electric power to propel the Off Highway Vehicle in the motoring mode.

14. The retrofit system of claim 13 wherein the electrical resistance system includes a resistance grid for dissipating a portion of the dynamic braking electrical power when the traction motor is operating in the power dissipating mode, and wherein the electrical energy storage system includes a first storage device coupled to the traction bus for storing electrical power, and a first auxiliary switching device responsive to dynamic braking electric power generated in the traction motor during the power dissipation mode for regulating power dissipation and maintaining the direct current bus voltage at a desired voltage magnitude by storing excess dynamic braking electrical power in the first storage device as secondary power.

15. The retrofit system of claim 14 wherein secondary power is selectively transmitted from the first storage device to the traction motor when the traction motor is operating in motoring mode to augment the primary electric power and assist in propelling the Off Highway Vehicle.

16. The retrofit system of claim 14 wherein the electrical energy storage system further comprises:

a second storage device coupled to the traction bus for storing electrical power; and

a second auxiliary switching device responsive to the dynamic braking electrical electric power generated in the traction motor during the dissipation mode for selectively transferring a second portion of the generated electrical power to the second storage device as second secondary power.

17. The retrofit system of claim 15 wherein secondary power is selectively transmitted from the second storage device to the traction motor when the traction motor is operating in motoring mode to augment the primary electric power and assist in propelling the Off Highway Vehicle.

18. A method for retrofitting an existing energy Off Highway Vehicle propulsion circuit such that the retrofitted propulsion circuit operates as an hybrid energy Off Highway Vehicle propulsion circuit, said existing vehicle propulsion circuit including a traction motor controlling a rotational speed of at least one wheel for propelling an Off Highway Vehicle, said traction motor having a dissipation mode of operation and a motoring mode of operation and driven by an engine providing primary electric power, wherein said first traction motor propels the Off Highway Vehicle in response to the primary electric power when operating in the motoring mode, and wherein said traction motor generates dynamic braking electrical power which is dissipated in an electrical resistance system to decrease the rotational speed of the at least one wheel when operating in the dissipating mode, and thereby, decrease the speed of the Off Highway Vehicle, said electrical resistance system including at a first resistor grid circuit and a second resistor grid circuit, wherein each of the first and second grid circuits includes one or more resistors and an auxiliary switching device, said method comprising:

disconnecting an auxiliary switch from the first resistor grid circuit;

installing a two position switch in the first resistor grid circuit;

disconnecting one or more resistors from the second resistor grid circuit;

installing a first energy storage device in the second resistor grid circuit, said auxiliary switching device in the second resistor grid circuit being responsive to dynamic braking electrical power generated in the traction motor during the power dissipation mode to transfer a portion of the dynamic braking electrical power to the first energy storage device; and

storing the transferred portion of braking electrical power in the first energy storage device as secondary power.

19. The method of claim 18 further including selectively transferring secondary power from the first storage device to the traction motor to augment the primary electric power to propel the Off Highway Vehicle in the motoring mode.

20. The method of claim 18 further including installing an energy storage grid, in addition to the first and second resistor grids, for selectively capturing electrical energy generated by the traction motor in the power dissipation mode.

21. The method of claim 20 wherein the installing includes installing a second energy storage device for storing an excess portion of the dynamic braking electrical power generated by the traction motor in the power dissipation mode, and includes installing an another auxiliary switching device responsive to the power dissipation mode for selectively transferring electrical power generated by the traction motor in the power dissipation mode to the storage device for storage as secondary electric power.

22. The method of claim 18 further including selectively transferring secondary power from the first storage device and from the second storage device to the traction motor to augment the primary electric power and assist in propelling the Off Highway Vehicle in the motoring mode.