UTILITY SCALE ELECTRIC ENERGY STORAGE SYSTEM

• US 20110037275A1
• Filed: 08/08/2010
• Published: 02/17/2011
• Est. Priority Date: 08/11/2009
• Status: Active Grant

• Current Assignee: Advanced Rail Energy Storage, LLC
• Original Assignee: Advanced Rail Energy Storage, LLC
• Inventors: Scott, David I., Blodgett, Douglas C., Brown, Matthew B., Scott, Robert T., Erdman, William L., Moorhead, William H., Peitzke, William R.
• Granted Patent: US 8,593,012 B2
• Time in Patent Office: Days
• US Class Current: 290/1.R
• 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 2220/14 Synchronous machines
• CPC Class Codes: B60L 55/00 Arrangements for supplying energy stored within a vehicle to a power network, i.e. vehicle-to-grid [V2G] arrangements
• CPC Class Codes: B60L 7/10 Dynamic electric regenerative braking B60L7/22 takes precedence
• CPC Class Codes: B61C 17/06 Power storing devices
• CPC Class Codes: B61C 3/00 Electric locomotives or railcars characterised by power transmission B61C9/00; electrical features B60L; H02
• CPC Class Codes: Y02E 60/00 Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• 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
• 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
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles
• CPC Class Codes: Y04S 10/126 the energy generation units being or involving electric vehicles [EV] or hybrid vehicles [HEV], i.e. power aggregation of EV or HEV, vehicle to grid arrangements [V2G]

Abstract

A potential energy storage system incorporating multiple track mounted shuttle units having motor/generator drive bogies and structure with an integral transfer mechanism for removably carrying energy storage masses from a first lower elevation storage yard to a second higher elevation storage yard employing excess energy from the electrical grid driving the motors, removing the masses in the second storage yard for energy storage, retrieving the masses and returning the masses from the second storage yard to the first storage yard recovering electrical energy through the generators.

Claims

1. An energy storage system comprising:

a rail system having upper and lower storage yards with interconnecting track connecting the upper and lower yards and a plurality of control elements for configuring track routing in the system;

a plurality of shuttle units having an electrical motor/generator interconnected to supporting wheels, said shuttle units further having a support structure and integral transfer mechanism for removably carrying masses;

means for electrical interconnection of the motor/generators to an electrical grid;

a control system in communication with the electrical grid, the plurality of shuttle units and the rail system control elements and having means for executing a first control sequence to store energy when the electrical grid has excess power and means for executing a second control sequence for providing power to the electrical grid when additional power is required,

said first control sequence causing selected shuttle units to retrieve masses located in the lower storage yard and using the motor/generator as a motor drawing power from the grid to drive the selected shuttle units from the lower storage yard to the upper storage yard, said control elements configured to route the selected shuttle units, and causing the selected shuttle units to offload the masses in the upper storage yard;

said second control sequence causing selected shuttle units to retrieve masses located in the upper storage yard and using the motor/generator as a generator supplying power to the grid by regenerative braking the selected shuttle units from the upper storage yard to the lower storage yard, said control elements configured to route the selected shuttle units, and causing the selected shuttle units to offload the masses in the lower storage yard.

2. The energy storage system of claim 1 wherein the masses are stored in the upper and lower storage yard suspended over storage yard tracks and each shuttle unit is received under selected masses and the transfer mechanism comprises a support element carried by structure on each shuttle unit and received under the mass as stored.

3. The energy storage system of claim 2 wherein the transfer mechanism lifts and rotates the mass from a suspended storage position.

4. The energy storage system of claim 1 wherein the means for electrical interconnection comprises:

a substation connected to the grid to receive high voltage power;

a trackside electrical distribution system connected to the substation;

a plurality of transformers connected to the electrical distribution system at selected intervals; and

,

a plurality of power supply rails connected to the transformers, each power supply rail associated with a track in the rail system.

5. The energy storage system of claim 4 wherein each of the plurality of shuttle units further comprises:

contactors for connection to the power supply rails;

a traction control unit (TCU) including

rectifier/inverter circuits for power control connected to the motor/generator

a control board for control of the rectifier/inverter circuits for acceleration, deceleration and steady state operation of the motor/generator.

6. The energy storage system of claim 5 wherein the TCU further comprises:

reversing bypass connectors responsive to a signal from the control board for selectively bypassing the rectifier inverter circuits with direct connection of the motor generator to the power supply rail for synchronous operation.

7. The energy storage system of claim 4 wherein the rectifier/inverter circuits comprise a first utility side rectifier/inverter and a second motor/generator side rectifier/inverter and the control board further comprises means for controlling reactive power in the utility side rectifier/inverter for VAR adjustment to the electrical grid.

8. The energy storage system of claim 4 wherein the control system includes means for signaling voltage adjustment in the system responsive to a utility signal for regulation up or regulation down and the TCU in each shuttle unit is responsive to said adjustment signals from the control system for asynchronous operation.

9. The energy storage system of claim 8 wherein the interconnecting track comprises a plurality of power tracks and at least one return track, at least one of said plurality of power tracks selected for asynchronous operation of shuttle units on the at least one selected track responsive to the voltage adjustment signaling by the control system.

10. The energy storage system of claim 1 wherein the integral transfer mechanism comprises:

a lever base mounted at a first end to a stanchion extending from a first bogie of each shuttle unit with a pivot pin;

a collapsible hinge attached to the lever base proximate a second end to a second bogie of the shuttle unit;

said hinge movable from a first collapsed position of the lever base wherein the shuttle unit may roll freely under a selected mass, to a second extended position to lift the lever base wherein the mass is lifted from a storage position.

11. The energy storage system of claim 1 wherein the integral transfer mechanism comprises:

multiple hydraulic rams;

a hydraulic lift incorporating a rotating engagement table positioned in the middle of the shuttle unit,

said lift extendible from a first position to a second position to lift a mass from a storage position, said hydraulic rams movable from a first position to a second position to rotate the engagement table aligning the mass longitudinally with the shuttle unit and said lift retractable to the first position,

said lift further extendible from the first position to the second position with the mass on the engagement table, said hydraulic rams movable from the second to the first position for orienting the mass transverse to the shuttle unit and said lift retractable to the first position for seating the mass in a storage location.

12. The energy storage system of claim 1 further comprising a second plurality of unpowered shuttle units selectively engaged to the first plurality of shuttle units forming consists with powered and unpowered shuttle units.

13. A method for utility scale energy storage comprising:

providing a rail system having upper and lower storage yards with interconnecting track connecting the upper and lower yards and a plurality of control elements for configuring track routing in the system;

providing a plurality of shuttle units having an electrical motor/generator interconnected to supporting wheels, said shuttle units further having a support structure and integral transfer mechanism for removably carrying masses;

connecting the rail system to an electrical grid;

upon receiving a command for energy storage, controlling a selected set of the plurality of shuttle units to each load a mass from a selected storage track in the lower storage yard;

connecting the storage track to a power track;

driving the motor/generator on each shuttle unit to lift the mass up the power track to the upper storage yard;

controlling the selected set of shuttle units to unload the masses to a selected storage track in the upper storage yard;

upon receiving a command for energy return, controlling a selected set of shuttle units each to load a mass from a selected storage track in the upper storage yard;

connecting the storage track to a power track;

braking the motor/generator on each shuttle unit to carry the mass down the power track to the lower storage yard;

controlling the shuttle unit to unload the mass to a selected storage track in the lower storage yard.

14. The method of claim 13 wherein connecting the system to an electrical grid includes providing a trackside power system including power supply rails associated with tracks in the rail system, and wherein providing a plurality shuttle units further comprises providing the shuttle units with rectifier/inverter circuits to provide power to the motor generator and wherein driving the motor/generator further comprises:

accelerating the motor generator to a synchronous operating speed;

bypassing the rectifier/inverter circuits;

directly connecting the motor/generator to the supply rail for synchronous operation.

15. The method of claim 14 wherein providing a rail system includes providing a plurality of power tracks intermediate the upper and lower storage yards and wherein driving the motor/generator further comprises:

selecting at least one power track for asynchronous operation; and

controlling the motor generator on shuttle units traversing the at least one power track for trimming and regulation up or regulation down of power supplied to or stored from the grid.

16. The method of claim 15 further comprising:

interconnecting the power supply rails in all tracks in the system;

absorbing power from the motor/generators for transient control during regulation down while supplying power to the grid by compensating power to returning shuttle units through the interconnected power supply rails; and

powering shuttle units in motor mode from returning shuttle units in generation mode.

17. The method of claim 13 wherein providing a plurality shuttle units further comprises providing the shuttle units with rectifier/inverter circuits to provide power to the motor generator and further comprising:

controlling reactive power in the rectifier/inverter circuits for VAR control adjustment to the electrical grid.

18. The method of claim 14 wherein synchronization is maintained by varying selected axles to be powered responsive to varying track grade.

19. A method for utility scale ancillary services comprising:

providing a rail system having upper and lower storage yards with a plurality of interconnecting tracks connecting the upper and lower yards and a plurality of control elements for configuring track routing in the system;

providing a plurality of shuttle units having an electrical motor/generator interconnected to supporting wheels and carrying masses;

connecting the rail system to an electrical grid;

upon receiving a command for ancillary service, controlling a selected set of the plurality of shuttle units for reactive power, acceleration and deceleration to interact with the electrical grid in satisfaction of the ancillary service command.

20. The method as defined in claim 19 wherein the command for ancillary service is a VAR command and further wherein providing a plurality shuttle units further comprises providing the shuttle units with rectifier/inverter circuits to provide power to the motor generator and further comprising:

controlling reactive power in the rectifier/inverter circuits for VAR control adjustment to the electrical grid.

21. The method of claim 19 wherein the ancillary service command is a regulation up/regulation down command and further comprising:

selecting at least one power track for asynchronous operation; and

controlling a motor generator on shuttle units traversing the at least one power track for regulation up or regulation down of power supplied to or stored from the grid.