DUAL FUEL SYSTEM AND METHOD OF SUPPLYING POWER TO LOADS OF A DRILLING RIG

• US 20120292992A1
• Filed: 05/09/2012
• Published: 11/22/2012
• Est. Priority Date: 12/04/2009
• Status: Active Grant

• Current Assignee: Nabors Drillling Technologies USA, Inc.
• Original Assignee: Kevin R. Williams
• Inventors: WILLIAMS, Kevin R.
• Granted Patent: US 9,065,300 B2
• Time in Patent Office: Days
• US Class Current: 307/23
• CPC Class Codes: F02D 19/0647 the gaseous fuel being liquefied petroleum gas [LPG], liquefied natural gas [LNG], compressed natural gas [CNG] or dimethyl ether [DME]
• CPC Class Codes: F02D 19/10 peculiar to compression-ignition engines in which the main fuel is gaseous
• CPC Class Codes: F02D 29/06 peculiar to engines driving electric generators
• CPC Class Codes: H02J 2300/10 The dispersed energy generation being of fossil origin, e.g. diesel generators
• CPC Class Codes: H02J 3/00 Circuit arrangements for ac mains or ac distribution networks
• CPC Class Codes: H02J 3/28 Arrangements for balancing of the load in a network by storage of energy
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 9/00 Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting
• CPC Class Codes: H02J 9/06 with automatic change-over , e.g. UPS systems
• CPC Class Codes: Y02T 10/30 Use of alternative fuels, e.g. biofuels

Abstract

A system for providing power to a load of a drilling rig has a dual fuel engine/generator and an energy storage system. The load is switchably connected to one or both of the dual fuel engine/generator and the energy storage system. The dual fuel engine/generator and the energy storage system have a capacity suitable for supplying requisite power to the load. A rectifier is connected to an output line of the engine/generator so as to convert the AC power to DC power. The energy storage system is a battery. The dual fuel engine/generator can be either a dedicated duel fuel system or a fumigation system.

Claims

1. A system for the supply power to a drilling rig, the system comprising:

a dual fuel engine/generator having an output line so as to supply AC power;

an energy storage system; and

a load switchably connected to one of said dual fuel engine/generator and said energy storage system, said dual fuel engine/generator and said energy storage system having a capacity suitable for supplying requisite power to said load.

2. The system of claim 1, further comprising:

a natural gas supply cooperative with said dual fuel engine/generator so as to supply natural gas to said dual fuel engine/generator; and

a diesel fuel supply cooperative with said dual fuel engine/generator so as to supply diesel fuel to said dual fuel engine/generator.

3. The system of claim 2, said natural gas supply being a wellhead gas.

4. The system of claim 2, said dual fuel engine/generator being a dedicated dual fuel engine/generator such that a fixed ratio of natural gas and diesel fuel is supplied to said dual fuel engine/generator.

5. The system of claim 2, said dual fuel engine/generator being a fumigation system such that a variable ratio of natural gas and diesel fuel is supplied to said dual fuel engine/generator.

6. The system of claim 1, further comprising:

a rectifying means connected to said output line of said dual fuel engine/generator, said rectifying means for converting the AC power to DC power.

7. The system of claim 6, said rectifying means being a silicon-controlled rectifier.

8. The system of claim 7, said silicon-controlled rectifier being phase-controlled so as to being responsive to a power requirement of said load.

9. The system of claim 1, further comprising:

a phase microcontroller connected to said load and to said dual fuel engine/generator, said phase microcontroller cooperative with said energy storage system so as to supply power from said energy storage system to said load individually or in combination with said dual fuel engine/generator.

10. The system of claim 1, said dual fuel engine/generator comprising a plurality of dual fuel engine/generators having the output line thereof connected to a common AC bus, said load comprising a plurality of loads connected by a line to a common DC bus, said energy storage system connected to said common DC bus.

11. The system of claim 10, further comprising:

a rectifying means connected between said common AC bus and said common DC bus so as to cause said plurality of dual fuel engine/generators to pass DC power to said common DC bus.

12. The system of claim 10, further comprising:

a plurality of autotransformers respectively connected between said plurality of dual fuel engine/generators and said common AC bus.

13. The system of claim 1, said energy storage system being a battery.

14. The system of claim 1, further comprising:

a switching means for switching a supply of power to said load between said dual fuel engine/generator and said energy storage system based on a power output of said dual fuel engine/generator and based upon the requisite power required by said load.

15. A method for the supply power to a drilling rig, the method comprising:

operating a dual fuel engine/generator so as to produce an AC power output;

providing an energy storage system switchably connected to a load; and

switching power supplied to the load between one or both of said dual fuel engine/generators and said energy storage system based upon a power requirement of the load.

16. The method of claim 15, said further comprising:

rectifying the AC power output from said dual fuel engine/generator so as to pass DC power to the load.

17. The method of claim 16, the step of switching comprising:

switching the rectified power by a phase-controlled microcontroller.

18. The method of claim 15, further comprising:

switching power from said dual fuel engine/generator to said energy storage system when the power output of the dual fuel engine/generator exceeds the power requirement of the load.

19. The method of claim 15, further comprising:

supplying a fixed ratio of natural gas and diesel fuel to said diesel fuel to said dual fuel engine/generator.

20. The method of claim 15, further comprising:

supplying a variable ratio of natural gas and diesel fuel to said dual fuel engine/generator.