US20060151211A1 - Transmitting electric power into a bore hole - Google Patents
Transmitting electric power into a bore hole Download PDFInfo
- Publication number
- US20060151211A1 US20060151211A1 US11/300,663 US30066305A US2006151211A1 US 20060151211 A1 US20060151211 A1 US 20060151211A1 US 30066305 A US30066305 A US 30066305A US 2006151211 A1 US2006151211 A1 US 2006151211A1
- Authority
- US
- United States
- Prior art keywords
- frequency
- electric
- electric current
- receiving station
- voltage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 230000005540 biological transmission Effects 0.000 claims abstract description 30
- 230000003247 decreasing effect Effects 0.000 claims description 11
- 238000005553 drilling Methods 0.000 claims description 8
- 238000003466 welding Methods 0.000 claims description 3
- 230000015572 biosynthetic process Effects 0.000 claims description 2
- 238000010892 electric spark Methods 0.000 claims description 2
- 238000000034 method Methods 0.000 claims 2
- 239000004020 conductor Substances 0.000 description 4
- 229930195733 hydrocarbon Natural products 0.000 description 4
- 150000002430 hydrocarbons Chemical class 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000003208 petroleum Substances 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 238000004804 winding Methods 0.000 description 2
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005669 field effect Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B47/00—Survey of boreholes or wells
- E21B47/12—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/003—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings with electrically conducting or insulating means
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B4/00—Drives for drilling, used in the borehole
- E21B4/04—Electric drives
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B41/00—Equipment or details not covered by groups E21B15/00 - E21B40/00
- E21B41/0085—Adaptations of electric power generating means for use in boreholes
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/12—Methods or apparatus for controlling the flow of the obtained fluid to or in wells
- E21B43/121—Lifting well fluids
- E21B43/128—Adaptation of pump systems with down-hole electric drives
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/36—Arrangements for transfer of electric power between ac networks via a high-tension dc link
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M5/00—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
- H02M5/40—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc
- H02M5/42—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters
- H02M5/44—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac
- H02M5/453—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]
Definitions
- the present invention relates to a system for transmitting electric power into a bore hole.
- This system is not considered suitable of transmitting much higher electric power at the motor voltage, for instance as high as 100 to 400 kW, since that would require very large cross section cable which would not fit in the coiled tubing. Moreover, such a cable would become so heavy that it would not be able to pull its own weight if it reaches into a typical bore hole suitable for production of hydrocarbons.
- the system comprises an electric transmission line extending through the bore hole between an electric power source and a receiving station and voltage converter means for changing the voltage of the electric current supplied to the receiving station
- the receiving station includes frequency increasing means for increasing the frequency of the electric current supplied through the electric transmission line, connecting means for supplying the frequency-increased electric current to the voltage converter means, and means for connecting an electric load to the receiving station, that the frequency increasing means is arranged to convert the electric current into three subsignals of increased frequency, each of which is 120° phase-shifted with respect to the other two, and whereby the voltage converter means change the voltage in each said subsignals, and that the frequency increasing means bring the frequency of the electric current to a value in a range of between 10 and 100 kHz.
- FIG. 1 schematically shows a wire line down hole power system for an AC load
- FIG. 2 schematically shows a wire line down hole power system for a DC load
- FIG. 3 schematically shows an electrical drill pipe and a down hole power system for a DC load
- FIG. 4 schematically shows a bore hole with an electric powered motorised expander cone.
- FIG. 5 schematically shows one example of a converter.
- FIG. 1 a system for transmitting electric power into a bore hole is schematically shown. Elements of the system are grouped in groups (1), (2) and (3), whereby group (1) corresponds to elements associated with the power source, group (2) corresponds to the electric transmission line (2), and group (3) corresponds to elements in the receiver station.
- the electric power source is connected to the receiving station via an electric transmission cable 7 .
- the bore hole is schematically represented by casing 8 .
- the electric power source in FIG. 1 which may typically be located on surface in the case that the bore hole reaches into an earth formation, comprises transformer means 5 for bringing the voltage of the electric current to be transmitted into the bore hole to a desired value, and a converter means 6 , here shown in the form of a current rectifier, for lowering the frequency of the electric current.
- a current rectifier has a DC current as output.
- the receiving station 9 comprises frequency increasing means 10 , which is electrically connected to voltage converter means 11 , here in the form of a coil transformer.
- the output of the voltage converter means 11 is connected to a load 12 .
- the system of FIG. 1 is typically fed with single phase or three-phase AC current having a 50 Hz or 60 Hz frequency and a relatively low voltage of less than approximately 1 kV. This is transformed in transformer 5 to a medium or voltage, of between 5 and 30 kV and rectified in rectifier 6 to a high DC voltage.
- the electric transmission line 7 brings the DC electric power into the bore hole.
- the distance over which the electric transmission line 7 reaches can be between several hundreds of meters and 10 km.
- the electric current reaches the receiving station 9 , where it its frequency is increased in frequency increasing means 10 , and its voltage is brought back in voltage converter means 11 to typically between 100 and 800 V, preferably between 400 and 800 V, depending on what is required by the nature of load 12 .
- the frequency preferably lies in a range of between 10 and 100 kHz, in which range there is an optimum compromise between the quality of the frequency increased current and the miniaturisation of the voltage converter means.
- the voltage converter means in the form of a coil transformer can comfortably fit in a tube having a diameter of approximately 15 cm. This makes the frequency specifically suitable for application in a bore hole, particularly in a bore hole for production of hydrocarbons.
- the load 12 is supplied with electric power of the same frequency as the voltage converter means 11 .
- this is appropriate, such as for electric power arc welding inside the bore hole.
- the load can be a desired tool operating at a specified voltage.
- the presence of the voltage converter means in the receiving station allows for the voltage in the electric transmission line to be relatively high compared to the voltage desired for operating the load, which is beneficial for achieving the high power transmission through a suitable transmission line. Due to the presence of the frequency increasing means in the receiving station, this system makes it possible to combine a relatively low frequency electric current, preferably direct current, in the electric transmission line with a relatively high frequency electric current in the voltage converter means.
- the reactive power loading in the transmission line is relatively low resulting in a high efficiency of power transmission.
- the size of typical transformers in inversely proportional to the current frequency, thus increasing the frequency allows for the use of a relatively small sized voltage converter means, such that it can fit in a typical bore hole suitable for production of hydrocarbons.
- the voltage converter means comprises contactless transformer means.
- a contactless transformer may typically comprise inductively coupled primary and secondary coil windings, preferably coupled via a magnetisable core such as an iron core.
- a transformer is ideally suited for high frequency voltage transformation, because the efficiency increases with frequency such that its size can decrease with increasing frequency.
- the system further comprises frequency decreasing means, preferably including a current rectifier, for reducing the frequency of electric current supplied to it via the voltage converter means, and second connecting means for supplying the voltage-changed electric current to the frequency decreasing means.
- frequency decreasing means preferably including a current rectifier, for reducing the frequency of electric current supplied to it via the voltage converter means, and second connecting means for supplying the voltage-changed electric current to the frequency decreasing means.
- the frequency decreasing means is then also arranged to combine three subsignals, each of which is 120° phase-shifted with respect to the other two, into one electric current of reduced frequency.
- the frequency must be decreased to several Hz or several tens of Hz, in particular 50 Hz or 60 Hz.
- An example is powering an AC powered electric motor.
- the frequency must even be decreased to zero resulting in a DC current.
- FIG. 2 A system for transmitting high power DC current in the bore hole is shown in FIG. 2 . This system largely corresponds to the system described above and depicted in FIG. 1 . The only difference is in the receiving station 13 , where a current rectifier 14 is provided in series with the voltage converter means 11 . Details of the current rectifier will be discussed further below.
- the receiving station 13 equates to a DC to DC power converter.
- suitable DC to DC power converters are shown and described in, for instance, U.S. Pat. No. 5,027,264, an article an article entitled “A three-phase soft-switched high-power-density dc/dc converter for high-power applications” published in IEEE transactions on Industrial Applications, Vol. 27 No. 1 (January/February 1991) by R. W. A. A. De Doncker, D. M. Divan, and M. H. Kheraluwala, and an article entitled “A three-phase series-parallel resonant converter—analysis, design, simulation, and experimental results” published in IEEE transactions on Industrial Applications, Vol. 32 no.
- the input converter may consist of an input capacitor bank and a three-phase converter with IGBTs and freewheeling diodes.
- the output converter may consist of a diode rectifier in case only power flow from input to output is required.
- the DC to DC converters generally have frequency increasing means composed of full or half bridges with active gate controlled switching devices which can be based on thyristor valves such as metal on semiconductor controlled thyristors (MCT's), or transistor valves such as insulated gate bipolar transistors (IGBT's), metal on semiconductor field effect transistors (MOSFET's).
- thyristor valves such as metal on semiconductor controlled thyristors (MCT's), or transistor valves such as insulated gate bipolar transistors (IGBT's), metal on semiconductor field effect transistors (MOSFET's).
- IGBT insulated gate bipolar transistors
- MOSFET's metal on semiconductor field effect transistors
- the current rectifier can be based on a bridge of diodes, or active gate controlled switching devices comprising diodes.
- the DC to DC converter can be operated in two directions, since a bridge based on active gate controlled switching devices function as frequency increasing means in one direction and as current rectifier in the other direction.
- the advantage of a rectifier based on active gate controlled switching devices is therefore that the down hole power system can also function to transmit electric power out of the bore hole.
- FIG. 3 schematically shows a down hole power system in accordance with the invention incorporated in an electrical drill pipe 19 .
- the receiving station is suitable for a DC load as in FIG. 2 , but in the case of FIG. 3 it is connectable to the drill pipe via connector 21 .
- the electric transmission line 17 is brought into the drill pipe 19 via side entry sub 20 .
- the electric power transmission system of FIG. 3 is the same as described above for FIG. 2 .
- a bore hole is provided with the system in accordance with one of the above described embodiments, and wherein an electric load in the form of a tool is connected to the receiving station for receiving voltage changed electric current.
- the tool may include one or more of: an electric welding tool, oil-water separator, an induction coil or heating device in general, a perforating tool, a valve system, an electric sparking tool such as an electric spark drilling tool, a motor-driven tool such as a traction device or a drilling assembly, preferably including a drill bit, or an electric submersible pump.
- the electric power transmission system may be combined with coiled tubing technology analogous to the transmission line described in paper SPE/IADC 52791 of the Society of Petroleum Engineers, entitled “Electric coiled tubing drilling: a smarter CT drilling system” by D. R. Turner et. al.
- FIG. 4 shows schematically type of load in the form of a tool depicted in group (4) comprising an expansion cone 17 driven by an electrically DC powered traction device 16 .
- This tool is moved upward through a casing tubing having a section 28 with a relatively narrow diameter in order to expand the casing tubing to a larger diameter to form expanded section 18 .
- the bit can be collapsed by pulling the drilling assembly into the casing again. This pulling force should enable shear pins that hold the gripping device to fail so that the tube is released again and the bit opens and the under-reaming arms can move to the retracted position
- the pivot means is relieved from taking the full torque load. It is thereby achieved that the pivot means is less vulnerable to damage due to transmission of high loads, without loosing reliability of switching the drill bit from the retracted to the expanded position and vice versa.
- the invention provides a hydraulic system for driving a pivoting movement of a pivotable tool arm between a radially retracted position and a radially expanded position
- the hydraulic system comprising a cylinder and piston means slidably arranged in the cylinder forming a drive chamber on one side of the piston means and a return chamber on the other side of the piston means, the piston means having a forward and a rearward position in the cylinder whereby the piston means is activatable to its rearward position by causing the drive force acting on the piston as a result of pressure in the drive chamber to exceed the return force acting on the piston as a result of pressure in the return chamber, which piston means is coupled to the pivotable tool arm for driving the tool arm from the retracted position to the expanded position when the piston is driven into its rearward position, whereby the piston means is coupled to gate means with is arranged such that the return force acting on the piston as a result of pressure in the return chamber exceeds the drive force acting on the piston as a result of pressure in the drive chamber when the hydraulic system
- the piston means When the tool arm is in its retracted position, the piston means can be positioned in or near its forward position where the gate means is switched such as to bias the piston means to its forward position.
- the gate means When the piston means is mechanically moved out of its forward position, the gate means is switched because it is coupled to the piston means, which results in the drive force acting on the piston as a result of pressure in the drive chamber exceeding the return force acting on the piston as a result of pressure in the return chamber. Consequently, the tool arm is pivoted to its expanded position and held in that position by the piston means.
- the starting situation, whereby the piston means is again biased in its forward position can be restored by mechanically forcing the piston means to its forward position, or by provision of additional gate means for regulating the pressures inside the drive chamber and return chamber such as to move the piston means forward on command.
- Such a traction device requires more than 200 kW, or even between 300 and 500 kW, in order to expand a typical casing tubing at an industrially acceptable rate.
- the receiving station 13 functions in the same way as described above with reference to FIG. 2 .
- the power transmitted via the system to the destination inside the bore hole lies in a range of 50 to 500 kW, preferably 200 to 500 kW, depending on the type of operation or application.
- Such high electric power can be transmitted in a cable having only 1.5 mm 2 cross sectional area, provided that the voltage is sufficiently high.
- the Ohmic resistance of the cable is less than 14 ⁇ /km, determined for DC at 20 C.
- a suitable cable is a commercially available HNOK cable from the firm Draka, which is a 8-mm diameter steel shielded coaxial power cable with a 1.5 mm 2 tin-plated copper central conductor that can conduct a current of 17 A DC.
- the insulation between the conductor and the steel shielding can support a potential difference of up to 20 kV between the conductor and the shielding.
- a theoretical maximum power of 340 kW is transmittable using this cable.
- the power is preferably limited to around 280 kW.
- a larger diameter core conductor and/or a thicker insulation layer will enable higher powers up to 500 kW.
- bypassing means are provided to feed to or extract from the electric transmission a data signal parallel to the receiving station. This enables utilization of the electric transmission line for carrying a data signal in addition to the high power transmission. Since such data signal does not have to be of high power, it does not need to pass through the receiving station.
Abstract
A system for transmitting electric power into a bore hole, the system having an electric transmission line extending through the bore hole between an electric power source and a receiving station, wherein the receiving station includes frequency increasing means for increasing the frequency of the electric current supplied through the electric transmission line, voltage converter means for changing the voltage of the electric current supplied to it via the frequency increasing means, connecting means for supplying the frequency-increased electric current to the voltage converter means, and means for connecting an electric load to the receiving station.
Description
- The present application claims priority on PCT/EP/2004/05196 filed Jun. 11, 2004.
- The present invention relates to a system for transmitting electric power into a bore hole.
- Such a system is known and described in paper SPE/IADC 52791 of the Society of Petroleum Engineers, entitled “Electric coiled tubing drilling: a smarter CT drilling system” by D. R. Turner et. al. In the known system, an electrically powered bottom hole assembly is connected to an electric coiled tubing that reaches into a bore hole. The electric coiled tubing holds an electric transmission line, for powering a down hole electric DC motor. The peak power output of this motor is 28 HP, corresponding to some 21 kW.
- This system is not considered suitable of transmitting much higher electric power at the motor voltage, for instance as high as 100 to 400 kW, since that would require very large cross section cable which would not fit in the coiled tubing. Moreover, such a cable would become so heavy that it would not be able to pull its own weight if it reaches into a typical bore hole suitable for production of hydrocarbons.
- According to some embodiments of the invention, the system comprises an electric transmission line extending through the bore hole between an electric power source and a receiving station and voltage converter means for changing the voltage of the electric current supplied to the receiving station, wherein the receiving station includes frequency increasing means for increasing the frequency of the electric current supplied through the electric transmission line, connecting means for supplying the frequency-increased electric current to the voltage converter means, and means for connecting an electric load to the receiving station, that the frequency increasing means is arranged to convert the electric current into three subsignals of increased frequency, each of which is 120° phase-shifted with respect to the other two, and whereby the voltage converter means change the voltage in each said subsignals, and that the frequency increasing means bring the frequency of the electric current to a value in a range of between 10 and 100 kHz.
- The invention will now be illustrated by way of example, with reference to the accompanying drawings wherein
-
FIG. 1 schematically shows a wire line down hole power system for an AC load; -
FIG. 2 schematically shows a wire line down hole power system for a DC load; -
FIG. 3 schematically shows an electrical drill pipe and a down hole power system for a DC load; -
FIG. 4 schematically shows a bore hole with an electric powered motorised expander cone. -
FIG. 5 schematically shows one example of a converter. - In the figures, like parts carry identical reference numerals.
- In
FIG. 1 a system for transmitting electric power into a bore hole is schematically shown. Elements of the system are grouped in groups (1), (2) and (3), whereby group (1) corresponds to elements associated with the power source, group (2) corresponds to the electric transmission line (2), and group (3) corresponds to elements in the receiver station. The electric power source is connected to the receiving station via anelectric transmission cable 7. The bore hole is schematically represented by casing 8. - The electric power source in
FIG. 1 , which may typically be located on surface in the case that the bore hole reaches into an earth formation, comprises transformer means 5 for bringing the voltage of the electric current to be transmitted into the bore hole to a desired value, and a converter means 6, here shown in the form of a current rectifier, for lowering the frequency of the electric current. A current rectifier has a DC current as output. - The receiving station 9 comprises
frequency increasing means 10, which is electrically connected to voltage converter means 11, here in the form of a coil transformer. The output of the voltage converter means 11 is connected to aload 12. - In practical operation, the system of
FIG. 1 is typically fed with single phase or three-phase AC current having a 50 Hz or 60 Hz frequency and a relatively low voltage of less than approximately 1 kV. This is transformed intransformer 5 to a medium or voltage, of between 5 and 30 kV and rectified inrectifier 6 to a high DC voltage. - The
electric transmission line 7 brings the DC electric power into the bore hole. In bore holes for production of hydrocarbon, the distance over which theelectric transmission line 7 reaches can be between several hundreds of meters and 10 km. At the destination in the bottom of the bore hole, the electric current reaches the receiving station 9, where it its frequency is increased infrequency increasing means 10, and its voltage is brought back in voltage converter means 11 to typically between 100 and 800 V, preferably between 400 and 800 V, depending on what is required by the nature ofload 12. - The frequency preferably lies in a range of between 10 and 100 kHz, in which range there is an optimum compromise between the quality of the frequency increased current and the miniaturisation of the voltage converter means. With a frequency of approximately 25 kHz, the voltage converter means in the form of a coil transformer can comfortably fit in a tube having a diameter of approximately 15 cm. This makes the frequency specifically suitable for application in a bore hole, particularly in a bore hole for production of hydrocarbons.
- In the case of
FIG. 1 , theload 12 is supplied with electric power of the same frequency as the voltage converter means 11. For some applications this is appropriate, such as for electric power arc welding inside the bore hole. - The load can be a desired tool operating at a specified voltage. The presence of the voltage converter means in the receiving station allows for the voltage in the electric transmission line to be relatively high compared to the voltage desired for operating the load, which is beneficial for achieving the high power transmission through a suitable transmission line. Due to the presence of the frequency increasing means in the receiving station, this system makes it possible to combine a relatively low frequency electric current, preferably direct current, in the electric transmission line with a relatively high frequency electric current in the voltage converter means.
- At relatively low frequency the reactive power loading in the transmission line is relatively low resulting in a high efficiency of power transmission. The size of typical transformers in inversely proportional to the current frequency, thus increasing the frequency allows for the use of a relatively small sized voltage converter means, such that it can fit in a typical bore hole suitable for production of hydrocarbons.
- Preferably the voltage converter means comprises contactless transformer means. Such a contactless transformer may typically comprise inductively coupled primary and secondary coil windings, preferably coupled via a magnetisable core such as an iron core. Such a transformer is ideally suited for high frequency voltage transformation, because the efficiency increases with frequency such that its size can decrease with increasing frequency.
- Optionally, the system further comprises frequency decreasing means, preferably including a current rectifier, for reducing the frequency of electric current supplied to it via the voltage converter means, and second connecting means for supplying the voltage-changed electric current to the frequency decreasing means. A number of loads require a relatively low frequency, or a direct current, for their operation, and for this reason the frequency decreasing means can be provided.
- Preferably, if the receiving station comprises frequency decreasing means, the frequency decreasing means is then also arranged to combine three subsignals, each of which is 120° phase-shifted with respect to the other two, into one electric current of reduced frequency.
- In some other applications, however, the frequency must be decreased to several Hz or several tens of Hz, in particular 50 Hz or 60 Hz. An example is powering an AC powered electric motor.
- In other embodiments, the frequency must even be decreased to zero resulting in a DC current. A system for transmitting high power DC current in the bore hole is shown in
FIG. 2 . This system largely corresponds to the system described above and depicted inFIG. 1 . The only difference is in thereceiving station 13, where acurrent rectifier 14 is provided in series with the voltage converter means 11. Details of the current rectifier will be discussed further below. - primary and secondary windings Functionally, the
receiving station 13 equates to a DC to DC power converter. Examples of suitable DC to DC power converters are shown and described in, for instance, U.S. Pat. No. 5,027,264, an article an article entitled “A three-phase soft-switched high-power-density dc/dc converter for high-power applications” published in IEEE transactions on Industrial Applications, Vol. 27 No. 1 (January/February 1991) by R. W. A. A. De Doncker, D. M. Divan, and M. H. Kheraluwala, and an article entitled “A three-phase series-parallel resonant converter—analysis, design, simulation, and experimental results” published in IEEE transactions on Industrial Applications, Vol. 32 no. 4 (July/August 1999) by A. K. S. Bhat and R. L. Zheng. These DC to DC converters are incorporated by reference. Another example of a DC to DC converter is a three-phase series resonant converter as shown inFIG. 5 . The input converter may consist of an input capacitor bank and a three-phase converter with IGBTs and freewheeling diodes. The output converter may consist of a diode rectifier in case only power flow from input to output is required. - The DC to DC converters generally have frequency increasing means composed of full or half bridges with active gate controlled switching devices which can be based on thyristor valves such as metal on semiconductor controlled thyristors (MCT's), or transistor valves such as insulated gate bipolar transistors (IGBT's), metal on semiconductor field effect transistors (MOSFET's). The DC to DC converters further have transformer means for changing the voltage of the increased frequency current, and a current rectifier.
- The current rectifier can be based on a bridge of diodes, or active gate controlled switching devices comprising diodes. In the latter case, the DC to DC converter can be operated in two directions, since a bridge based on active gate controlled switching devices function as frequency increasing means in one direction and as current rectifier in the other direction. The advantage of a rectifier based on active gate controlled switching devices is therefore that the down hole power system can also function to transmit electric power out of the bore hole.
-
FIG. 3 schematically shows a down hole power system in accordance with the invention incorporated in anelectrical drill pipe 19. The receiving station is suitable for a DC load as inFIG. 2 , but in the case ofFIG. 3 it is connectable to the drill pipe viaconnector 21. Theelectric transmission line 17 is brought into thedrill pipe 19 viaside entry sub 20. In other aspects and in its operation, the electric power transmission system ofFIG. 3 is the same as described above forFIG. 2 . - In another embodiment, a bore hole is provided with the system in accordance with one of the above described embodiments, and wherein an electric load in the form of a tool is connected to the receiving station for receiving voltage changed electric current. The tool may include one or more of: an electric welding tool, oil-water separator, an induction coil or heating device in general, a perforating tool, a valve system, an electric sparking tool such as an electric spark drilling tool, a motor-driven tool such as a traction device or a drilling assembly, preferably including a drill bit, or an electric submersible pump.
- As an alternative to
FIG. 3 , the electric power transmission system may be combined with coiled tubing technology analogous to the transmission line described in paper SPE/IADC 52791 of the Society of Petroleum Engineers, entitled “Electric coiled tubing drilling: a smarter CT drilling system” by D. R. Turner et. al. -
FIG. 4 shows schematically type of load in the form of a tool depicted in group (4) comprising anexpansion cone 17 driven by an electrically DC poweredtraction device 16. This tool is moved upward through a casing tubing having asection 28 with a relatively narrow diameter in order to expand the casing tubing to a larger diameter to form expandedsection 18. - Among other features that may be included in the drill bit are:
- A gripping device for locking the tube once the arms have reached the fully expanded position by hydraulic actuation via the piston and tube. This way the bit is locked in expanded position. At the end of a bit run the bit can be collapsed by pulling the drilling assembly into the casing again. This pulling force should enable shear pins that hold the gripping device to fail so that the tube is released again and the bit opens and the under-reaming arms can move to the retracted position
- By virtue of the provision of the support means, the pivot means is relieved from taking the full torque load. It is thereby achieved that the pivot means is less vulnerable to damage due to transmission of high loads, without loosing reliability of switching the drill bit from the retracted to the expanded position and vice versa.
- In another embodiment, the invention provides a hydraulic system for driving a pivoting movement of a pivotable tool arm between a radially retracted position and a radially expanded position, the hydraulic system comprising a cylinder and piston means slidably arranged in the cylinder forming a drive chamber on one side of the piston means and a return chamber on the other side of the piston means, the piston means having a forward and a rearward position in the cylinder whereby the piston means is activatable to its rearward position by causing the drive force acting on the piston as a result of pressure in the drive chamber to exceed the return force acting on the piston as a result of pressure in the return chamber, which piston means is coupled to the pivotable tool arm for driving the tool arm from the retracted position to the expanded position when the piston is driven into its rearward position, whereby the piston means is coupled to gate means with is arranged such that the return force acting on the piston as a result of pressure in the return chamber exceeds the drive force acting on the piston as a result of pressure in the drive chamber when the piston means is in or near its forward position whereas the opposite is the case when the piston means is in a position other than in or near its forward position.
- When the tool arm is in its retracted position, the piston means can be positioned in or near its forward position where the gate means is switched such as to bias the piston means to its forward position. When the piston means is mechanically moved out of its forward position, the gate means is switched because it is coupled to the piston means, which results in the drive force acting on the piston as a result of pressure in the drive chamber exceeding the return force acting on the piston as a result of pressure in the return chamber. Consequently, the tool arm is pivoted to its expanded position and held in that position by the piston means. The starting situation, whereby the piston means is again biased in its forward position can be restored by mechanically forcing the piston means to its forward position, or by provision of additional gate means for regulating the pressures inside the drive chamber and return chamber such as to move the piston means forward on command.
- Such a traction device requires more than 200 kW, or even between 300 and 500 kW, in order to expand a typical casing tubing at an industrially acceptable rate. The receiving
station 13 functions in the same way as described above with reference toFIG. 2 . - For some applications the power transmitted via the system to the destination inside the bore hole lies in a range of 50 to 500 kW, preferably 200 to 500 kW, depending on the type of operation or application. Such high electric power can be transmitted in a cable having only 1.5 mm2 cross sectional area, provided that the voltage is sufficiently high. Preferably, the Ohmic resistance of the cable is less than 14 Ω/km, determined for DC at 20 C.
- One example of a suitable cable is a commercially available HNOK cable from the firm Draka, which is a 8-mm diameter steel shielded coaxial power cable with a 1.5 mm2 tin-plated copper central conductor that can conduct a current of 17 A DC. The insulation between the conductor and the steel shielding can support a potential difference of up to 20 kV between the conductor and the shielding. Thus a theoretical maximum power of 340 kW is transmittable using this cable. In practice the power is preferably limited to around 280 kW. A larger diameter core conductor and/or a thicker insulation layer will enable higher powers up to 500 kW.
- In one embodiment, bypassing means are provided to feed to or extract from the electric transmission a data signal parallel to the receiving station. This enables utilization of the electric transmission line for carrying a data signal in addition to the high power transmission. Since such data signal does not have to be of high power, it does not need to pass through the receiving station.
Claims (16)
1. A system for transmitting electric power into a bore hole, the system comprising an electric transmission line extending through the bore hole between an electric power source and a receiving station and voltage converter means for changing the voltage of the electric current supplied to the receiving station, wherein the receiving station includes frequency increasing means for increasing the frequency of electric current supplied through the electric transmission line, connecting means for supplying the frequency-increased electric current to the voltage converter means, and means for connecting an electric load to the receiving station, that the frequency increasing means is arranged to convert the electric current into three subsignals of increased frequency, each of which is 120° phase-shifted with respect to the other two, whereby the voltage converter means changes the voltage in each said subsignals, and the frequency increasing means bring the frequency of the electric current to a value in a range of between 10 and 100 kHz.
2. The system of claim 1 , wherein the voltage converter means comprises contactless transformer means.
3. The system of claim 1 , comprising frequency decreasing means arranged to reduce the frequency of electric current supplied to it via the voltage converter means.
4. The system of claim 3 , wherein the frequency decreasing means comprises a current rectifier.
5. The system of claim 3 , wherein the frequency decreasing means is arranged to combine three subsignals, each of which is 120° phase-shifted with respect to the other two, into one electric current of reduced frequency.
6. The system of claim 1 , wherein bypassing means are provided to feed to or extract from the electric transmission a data signal parallel to the receiving station.
7. A bore hole extending into an earth formation, the bore hole being provided with the system for transmitting electric power into a bore hole, the system comprising an electric transmission line extending through the bore hole between an electric power source and a receiving station and voltage converter means for changing the voltage of the electric current supplied to the receiving station; wherein the receiving station includes frequency increasing means for increasing the frequency of electric current supplied through the electric transmission line; connecting means for supplying the frequency-increased electric current to the voltage converter means; and means for connecting an electric load to the receiving station, that the frequency increasing means is arranged to convert the electric current into three subsignals of increased frequency, each of which is 120° phase-shifted with respect to the other two, whereby the voltage converter means changes the voltage in each said subsignals, and the frequency increasing means brings the frequency of the electric current to a value in a range of between 10 and 100 kHz wherein an electric load in the form of a tool is connected to the receiving station for receiving voltage changed electric current.
8. The bore hole of claim 7 , wherein the tool comprises an electric welding.
9. A method of transmitting electric power into a bore hole, wherein electric current is transmitted from an electric power source to a receiving station via an electric transmission line, in which receiving station the voltage of the electric current supplied to it is changed in voltage converter means, wherein in the receiving station the frequency of the electric current supplied through the electric transmission line is increased by frequency increasing means, wherein the frequency increasing means convert the electric current into three subsignals of increased frequency, each of which is 120° phase-shifted with respect to the other two, whereby the voltage converter means change the voltage in each said subsignals, and that frequency increasing means bring the frequency of the electric current to a value in a range of between 10 and 100 kHz.
10. The method of claim 11 , wherein the electric current is supplied to frequency decreasing means where the frequency of electric current supplied to it via the voltage converter means is reduced.
11. The borehole of claim 7 , wherein the tool comprises an electric spark drilling tool.
12. The borehole of claim 7 , wherein the tool comprises a motor-driven tool
13. The borehole of claim 12 , wherein the motor-driven tool is a traction device.
14. The borehole of claim 12 , wherein the motor-driven tool is a drill bit.
15. The borehole of claim 13 , further comprising an expansion cone coupled to the traction device.
16. The borehole of claim 14 , further comprising an expansion cone coupled to the traction device.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US12/732,055 US8665110B2 (en) | 2003-06-13 | 2010-03-25 | Transmitting electric power into a bore hole |
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP03253754 | 2003-06-13 | ||
PCT/EP2004/051096 WO2004111389A1 (en) | 2003-06-13 | 2004-06-11 | System and method for transmitting electric power into a bore |
WOPCT/EP04/05196 | 2004-06-11 |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP2004/051096 Continuation WO2004111389A1 (en) | 2003-06-13 | 2004-06-11 | System and method for transmitting electric power into a bore |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US12/732,055 Division US8665110B2 (en) | 2003-06-13 | 2010-03-25 | Transmitting electric power into a bore hole |
Publications (1)
Publication Number | Publication Date |
---|---|
US20060151211A1 true US20060151211A1 (en) | 2006-07-13 |
Family
ID=33547786
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/300,663 Abandoned US20060151211A1 (en) | 2003-06-13 | 2005-12-13 | Transmitting electric power into a bore hole |
US12/732,055 Expired - Fee Related US8665110B2 (en) | 2003-06-13 | 2010-03-25 | Transmitting electric power into a bore hole |
Family Applications After (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US12/732,055 Expired - Fee Related US8665110B2 (en) | 2003-06-13 | 2010-03-25 | Transmitting electric power into a bore hole |
Country Status (7)
Country | Link |
---|---|
US (2) | US20060151211A1 (en) |
CN (1) | CN100472031C (en) |
AU (1) | AU2004247900B9 (en) |
BR (1) | BRPI0411292A (en) |
CA (1) | CA2529135C (en) |
GB (1) | GB2418304B (en) |
WO (1) | WO2004111389A1 (en) |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20100284521A1 (en) * | 2009-05-11 | 2010-11-11 | General Electric Company | Digital image detector |
US20100288501A1 (en) * | 2009-05-18 | 2010-11-18 | Fielder Lance I | Electric submersible pumping system for dewatering gas wells |
US20100288493A1 (en) * | 2009-05-18 | 2010-11-18 | Fielder Lance I | Cable suspended pumping system |
US8408312B2 (en) | 2010-06-07 | 2013-04-02 | Zeitecs B.V. | Compact cable suspended pumping system for dewatering gas wells |
US20140192621A1 (en) * | 2013-01-07 | 2014-07-10 | Baker Hughes Incorporated | Apparatus and method for communication between downhole components |
US20150083491A1 (en) * | 2013-09-23 | 2015-03-26 | Sdg Llc | Method and apparatus for isolating and switching lower voltage pulses from high voltage pulses in electrocrushing and electrohydraulic drills |
US9482078B2 (en) | 2012-06-25 | 2016-11-01 | Zeitecs B.V. | Diffuser for cable suspended dewatering pumping system |
US10060195B2 (en) | 2006-06-29 | 2018-08-28 | Sdg Llc | Repetitive pulsed electric discharge apparatuses and methods of use |
US10110013B2 (en) * | 2015-07-24 | 2018-10-23 | General Electric Company | Downhole switch assemblies and methods |
US10407995B2 (en) | 2012-07-05 | 2019-09-10 | Sdg Llc | Repetitive pulsed electric discharge drills including downhole formation evaluation |
Families Citing this family (21)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2448928B (en) * | 2007-05-04 | 2009-12-09 | Dynamic Dinosaurs Bv | Power transmission system for use with downhole equipment |
CN101515039B (en) * | 2008-02-19 | 2013-01-23 | 中油测井技术服务有限责任公司 | Underground power supply and signal transmission system |
NO332768B1 (en) * | 2009-12-16 | 2013-01-14 | Smartmotor As | System for operation of elongated electric machines |
GB2500495B (en) * | 2010-09-13 | 2018-10-31 | Aker Solutions As | Stable subsea electric power transmission to run subsea high speed motors |
US20140183963A1 (en) * | 2012-12-28 | 2014-07-03 | Kenneth B. Wilson | Power Transmission in Drilling and related Operations using structural members as the Transmission Line |
EP2792841A1 (en) * | 2013-04-18 | 2014-10-22 | Welltec A/S | Downhole tool capable of withstanding high temperatures |
US9951779B2 (en) | 2013-12-27 | 2018-04-24 | General Electric Company | Methods and systems for subsea boosting with direct current and alternating current power systems |
US9611855B2 (en) * | 2013-12-27 | 2017-04-04 | General Electric Company | Methods and systems for direct current power system subsea boosting |
US9537428B2 (en) | 2014-01-14 | 2017-01-03 | General Electric Company | Combined power transmission and heating systems and method of operating the same |
US9896912B2 (en) | 2015-05-13 | 2018-02-20 | Baker Hughes, A Ge Company, Llc | Active rectifier for downhole applications |
US10858911B2 (en) * | 2015-09-04 | 2020-12-08 | Baker Hughes, A Ge Company, Llc | Bidirectional chopping of high voltage power in high temperature downhole tools to reduce tool size |
WO2017099968A1 (en) | 2015-12-11 | 2017-06-15 | Schlumberger Technology Corporation | System and method related to pumping fluid in a borehole |
US10855142B2 (en) * | 2016-04-19 | 2020-12-01 | Supreme Electrical Services, Inc. | Power system for well service pumps |
WO2017192133A1 (en) * | 2016-05-04 | 2017-11-09 | Halliburton Energy Services, Inc. | Overvoltage protection of downhole generators |
US10196921B2 (en) | 2016-06-20 | 2019-02-05 | Baker Hughes, A Ge Company, Llc | Modular downhole generator |
CA3036671C (en) | 2016-10-13 | 2023-03-07 | Halliburton Energy Services, Inc. | Dynamic generator voltage control for high power drilling and logging-while-drilling |
US11072999B2 (en) | 2016-12-30 | 2021-07-27 | Metrol Technology Ltd. | Downhole energy harvesting |
MX2019007941A (en) | 2016-12-30 | 2019-11-18 | Metrol Tech Ltd | Downhole energy harvesting. |
US11236586B2 (en) | 2016-12-30 | 2022-02-01 | Metrol Technology Ltd. | Downhole energy harvesting |
WO2018122547A1 (en) * | 2016-12-30 | 2018-07-05 | Metrol Technology Ltd | Downhole energy harvesting |
EP4151832A1 (en) * | 2017-03-31 | 2023-03-22 | Metrol Technology Ltd | Monitoring well installations |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5208740A (en) * | 1991-05-30 | 1993-05-04 | The Texas A & M University System | Inverse dual converter for high-power applications |
US5684683A (en) * | 1996-02-09 | 1997-11-04 | Wisconsin Alumni Research Foundation | DC-to-DC power conversion with high current output |
US6304460B1 (en) * | 2000-05-05 | 2001-10-16 | Slobodan Cuk | Switching DC-to-DC converter utilizing a soft switching technique |
US6923273B2 (en) * | 1997-10-27 | 2005-08-02 | Halliburton Energy Services, Inc. | Well system |
US6995683B2 (en) * | 2004-03-12 | 2006-02-07 | Welldynamics, Inc. | System and method for transmitting downhole data to the surface |
US7109691B2 (en) * | 2002-06-28 | 2006-09-19 | Microsemi Corporation | Systems for auto-interleaving synchronization in a multiphase switching power converter |
US7436684B2 (en) * | 2003-06-11 | 2008-10-14 | Telefonaktiebolaget Lm Ericsson (Publ) | DC/DC-rectifier with reduced losses |
US7439821B2 (en) * | 2005-03-14 | 2008-10-21 | Alfred E. Mann Foundation For Scientific Research | DC to DC transmission system |
Family Cites Families (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4901069A (en) * | 1987-07-16 | 1990-02-13 | Schlumberger Technology Corporation | Apparatus for electromagnetically coupling power and data signals between a first unit and a second unit and in particular between well bore apparatus and the surface |
US5027264A (en) * | 1989-09-29 | 1991-06-25 | Wisconsin Alumni Research Foundation | Power conversion apparatus for DC/DC conversion using dual active bridges |
US5207273A (en) * | 1990-09-17 | 1993-05-04 | Production Technologies International Inc. | Method and apparatus for pumping wells |
SE504301C2 (en) * | 1993-12-03 | 1996-12-23 | Asea Brown Boveri | Device for draining electrical power from a high voltage direct current transmission line |
US5844397A (en) * | 1994-04-29 | 1998-12-01 | Reda Pump | Downhole pumping system with variable speed pulse width modulated inverter coupled to electrical motor via non-gap transformer |
US5610501A (en) * | 1995-02-01 | 1997-03-11 | Westinghouse Electric Corporation | Dynamic power and voltage regulator for an ac transmission line |
US5656925A (en) * | 1996-01-22 | 1997-08-12 | Juno Lighting, Inc. | Pulse switching tandem flyback voltage converter |
US6043995A (en) * | 1998-09-09 | 2000-03-28 | Centrilift | Method and apparatus for pulse width modulation of a power supply for increased transient stability in subsurface wellbore pumps |
US6469636B1 (en) * | 1998-12-02 | 2002-10-22 | Halliburton Energy Services, Inc. | High-power well logging method and apparatus |
GB9908386D0 (en) * | 1999-04-14 | 1999-06-09 | Axon Instr Limited | Telemetry system |
AU2001227566A1 (en) * | 2000-01-18 | 2001-07-31 | Haliburton Energy Services, Inc. | Downhole electrical transmission system |
JP3626152B2 (en) * | 2002-06-19 | 2005-03-02 | ファナック株式会社 | Motor drive control device |
US7701106B2 (en) * | 2003-06-21 | 2010-04-20 | Oilfield Equipment Development Center Limited | Electric submersible pumps |
GB0314553D0 (en) * | 2003-06-21 | 2003-07-30 | Weatherford Lamb | Electric submersible pumps |
US7164242B2 (en) * | 2004-02-27 | 2007-01-16 | York International Corp. | Variable speed drive for multiple loads |
US7425806B2 (en) * | 2004-04-12 | 2008-09-16 | York International Corporation | System and method for controlling a variable speed drive |
US7708059B2 (en) * | 2007-11-13 | 2010-05-04 | Baker Hughes Incorporated | Subsea well having a submersible pump assembly with a gas separator located at the pump discharge |
-
2004
- 2004-06-11 AU AU2004247900A patent/AU2004247900B9/en not_active Ceased
- 2004-06-11 GB GB0525255A patent/GB2418304B/en not_active Expired - Fee Related
- 2004-06-11 CN CNB2004800165600A patent/CN100472031C/en not_active Expired - Fee Related
- 2004-06-11 CA CA2529135A patent/CA2529135C/en not_active Expired - Fee Related
- 2004-06-11 BR BRPI0411292-0A patent/BRPI0411292A/en not_active IP Right Cessation
- 2004-06-11 WO PCT/EP2004/051096 patent/WO2004111389A1/en active Application Filing
-
2005
- 2005-12-13 US US11/300,663 patent/US20060151211A1/en not_active Abandoned
-
2010
- 2010-03-25 US US12/732,055 patent/US8665110B2/en not_active Expired - Fee Related
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5208740A (en) * | 1991-05-30 | 1993-05-04 | The Texas A & M University System | Inverse dual converter for high-power applications |
US5684683A (en) * | 1996-02-09 | 1997-11-04 | Wisconsin Alumni Research Foundation | DC-to-DC power conversion with high current output |
US6923273B2 (en) * | 1997-10-27 | 2005-08-02 | Halliburton Energy Services, Inc. | Well system |
US6304460B1 (en) * | 2000-05-05 | 2001-10-16 | Slobodan Cuk | Switching DC-to-DC converter utilizing a soft switching technique |
US7109691B2 (en) * | 2002-06-28 | 2006-09-19 | Microsemi Corporation | Systems for auto-interleaving synchronization in a multiphase switching power converter |
US7436684B2 (en) * | 2003-06-11 | 2008-10-14 | Telefonaktiebolaget Lm Ericsson (Publ) | DC/DC-rectifier with reduced losses |
US6995683B2 (en) * | 2004-03-12 | 2006-02-07 | Welldynamics, Inc. | System and method for transmitting downhole data to the surface |
US7439821B2 (en) * | 2005-03-14 | 2008-10-21 | Alfred E. Mann Foundation For Scientific Research | DC to DC transmission system |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10060195B2 (en) | 2006-06-29 | 2018-08-28 | Sdg Llc | Repetitive pulsed electric discharge apparatuses and methods of use |
US8324585B2 (en) * | 2009-05-11 | 2012-12-04 | General Electric Company | Digital image detector |
US20100284521A1 (en) * | 2009-05-11 | 2010-11-11 | General Electric Company | Digital image detector |
US8833441B2 (en) * | 2009-05-18 | 2014-09-16 | Zeitecs B.V. | Cable suspended pumping system |
US20100288501A1 (en) * | 2009-05-18 | 2010-11-18 | Fielder Lance I | Electric submersible pumping system for dewatering gas wells |
US20100288493A1 (en) * | 2009-05-18 | 2010-11-18 | Fielder Lance I | Cable suspended pumping system |
US8443900B2 (en) | 2009-05-18 | 2013-05-21 | Zeitecs B.V. | Electric submersible pumping system and method for dewatering gas wells |
US8770271B2 (en) | 2009-05-18 | 2014-07-08 | Zeitecs B.V. | Electric submersible pumping system for dewatering gas wells |
US8408312B2 (en) | 2010-06-07 | 2013-04-02 | Zeitecs B.V. | Compact cable suspended pumping system for dewatering gas wells |
US8584761B2 (en) | 2010-06-07 | 2013-11-19 | Zeitecs B.V. | Compact cable suspended pumping system for dewatering gas wells |
US9482078B2 (en) | 2012-06-25 | 2016-11-01 | Zeitecs B.V. | Diffuser for cable suspended dewatering pumping system |
US10407995B2 (en) | 2012-07-05 | 2019-09-10 | Sdg Llc | Repetitive pulsed electric discharge drills including downhole formation evaluation |
US20140192621A1 (en) * | 2013-01-07 | 2014-07-10 | Baker Hughes Incorporated | Apparatus and method for communication between downhole components |
US20150083491A1 (en) * | 2013-09-23 | 2015-03-26 | Sdg Llc | Method and apparatus for isolating and switching lower voltage pulses from high voltage pulses in electrocrushing and electrohydraulic drills |
US10113364B2 (en) * | 2013-09-23 | 2018-10-30 | Sdg Llc | Method and apparatus for isolating and switching lower voltage pulses from high voltage pulses in electrocrushing and electrohydraulic drills |
US10110013B2 (en) * | 2015-07-24 | 2018-10-23 | General Electric Company | Downhole switch assemblies and methods |
Also Published As
Publication number | Publication date |
---|---|
AU2004247900A1 (en) | 2004-12-23 |
CN100472031C (en) | 2009-03-25 |
CN1806091A (en) | 2006-07-19 |
BRPI0411292A (en) | 2006-08-01 |
GB0525255D0 (en) | 2006-01-18 |
AU2004247900B9 (en) | 2008-06-05 |
WO2004111389A1 (en) | 2004-12-23 |
GB2418304A (en) | 2006-03-22 |
US8665110B2 (en) | 2014-03-04 |
CA2529135C (en) | 2012-01-24 |
CA2529135A1 (en) | 2004-12-23 |
AU2004247900B2 (en) | 2008-01-10 |
US20110170320A1 (en) | 2011-07-14 |
GB2418304B (en) | 2006-11-08 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8665110B2 (en) | Transmitting electric power into a bore hole | |
US20030102720A1 (en) | Underwater hydrocarbon production systems | |
EP2546454B1 (en) | Dc powered subsea inverter | |
US11322942B2 (en) | Electrical power generation and distribution system with power recovery and regeneration | |
CN102239632B (en) | Voltage control and power factor correction in AC induction motors | |
SG185501A1 (en) | Power supply system and method with remote variable frequency drive (vfd) | |
US20120319474A1 (en) | Systems and Methods for Transmission of Electric Power to Downhole Equipment | |
CN111030314A (en) | Carrier rocket ground high-power wireless power supply system based on electromagnetic resonance | |
CN110350789A (en) | Insulated type DC/DC converter and its control device and DC/AC conversion equipment | |
CN1335668A (en) | Voltage balancer circuit for power converter | |
EP2773835B1 (en) | Mining vehicle | |
CN106208084B (en) | A kind of dynamic electric voltage recovery device and its intelligent control method | |
CN106160024A (en) | A kind of high-voltage power transmission device towards wireless energy transfer system | |
CN212785221U (en) | Frequency converter control device for simultaneously controlling motor and electric heating device | |
CN109904874A (en) | A kind of long-range transmission & distribution method for electrically of ocean controllable source electromagnetism superhigh voltage DC | |
CN103959588B (en) | The extremely length of alternating electromotive force walks out of Transmission system | |
CN112728273A (en) | Heating device penetrates in variable frequency pipeline | |
US20220148761A1 (en) | Systems and methods for balancing unbalanced power cables | |
CN1056485C (en) | Invertor power supply containing magnetic amplifier and method for controlling its output | |
CN102291009A (en) | Motor driving power supply for rotary sidewall sampler | |
KR102608603B1 (en) | Modular input-parallel output-serial connection induction heating inverter circuit for high voltage output and inverter circuit operation method | |
CN116961173A (en) | Super capacitor energy storage net electric workover rig | |
CN104675387A (en) | Rectifier and inverter probe tube | |
CN107517008A (en) | Three-phase AC AC converters and its control method for radio energy transmission system | |
CN116317189A (en) | Non-contact electric energy transmission device for improving power density |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: SHELL OIL COMPANY, TEXAS Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:COENE, JOSEF GUILLAUME CHRISTOFFEL;TAN BOON KIAT, IVAN;REEL/FRAME:017654/0692;SIGNING DATES FROM 20060109 TO 20060206 |
|
AS | Assignment |
Owner name: A-POWER GMBH, GERMANY Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:SHELL OIL COMPANY;REEL/FRAME:024926/0025 Effective date: 20100726 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |