Tapered string pulse power rock excavation system
AssigneeHalliburton Energy Services, Inc.
InventorRichard T. Hay
Life of this patent
Estimating the term…
Abstract
Systems and methods for drilling a wellbore include delivering electrical energy to a downhole end of the wellbore. A tapered drill string, with larger drill pipes connected in an up-hole portion with a turbine and an electrical generator and a smaller drill pipes coupled in downhole portion may be used to deliver the electrical power. A turbine and generator may be sufficiently sized to harvest the necessary hydraulic energy and safely operated in a subterranean environment. An electrode carried by the downhole portion of the drill string is electrically coupled to the generator through the downhole portion of the drill string.
Claims20
A method for forming a wellbore in a geologic formation with a high-voltage drilling system, the method comprising:
- forming an up-hole portion of the wellbore to have an up-hole diameter;
- coupling one or more electrodes to a downhole portion of a drill string;
- coupling an electrical generator that is part of an up-hole portion of the drill string to the downhole portion of the drill string such that the electrical generator is electrically coupled to the one or more electrodes;
- lowering the electrical generator into the up-hole portion of the wellbore on the up-hole portion of the drill string;
- circulating a wellbore fluid through the wellbore to cause the electrical generator to produce electrical power within the up-hole portion of the wellbore;
- and
- delivering the electrical power to the one or more electrodes to form a downhole portion of the wellbore with a downhole diameter less than the up-hole diameter, wherein forming the downhole portion of the wellbore includes maintaining the electrical generator in the up-hole portion of the wellbore producing the electrical power, the electrical generator having a generator diameter that is greater than the downhole diameter of the downhole portion of the wellbore.
A high voltage drilling system for forming a wellbore, comprising:
- a downhole portion of a drill string including one or more electrodes at a downhole end thereof;
- an electrical conductor extending through the downhole portion of the drill string and coupled to the one or more electrodes;
- an up-hole portion of the drill string coupled to the downhole portion of the drill string, the up-hole portion of the drill string including an electrical generator electrically coupled to the one or more electrodes through the electrical conductor, wherein the electrical generator is configured to produce electrical power for the one or more electrodes;
- and
- the one or more electrodes configured to form a downhole portion of the wellbore while maintaining the electrical generator in an up-hole portion of the wellbore producing the electrical power, the electrical generator having a generator diameter that is greater than a downhole diameter of the downhole portion of the wellbore.
Dependencies are inferred from the claim text.