Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02B—BOARDS, SUBSTATIONS OR SWITCHING ARRANGEMENTS FOR THE SUPPLY OR DISTRIBUTION OF ELECTRIC POWER
  • H02B3/00—Apparatus specially adapted for the manufacture, assembly, or maintenance of boards or switchgear
• • 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
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
  • G02B6/44—Mechanical structures for providing tensile strength and external protection for fibres, e.g. optical transmission cables
  • G02B6/4401—Optical cables
  • G02B6/4415—Cables for special applications
  • G02B6/4416—Heterogeneous cables
  • G02B6/4417—High voltage aspects, e.g. in cladding
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
  • G02B6/44—Mechanical structures for providing tensile strength and external protection for fibres, e.g. optical transmission cables
  • G02B6/4401—Optical cables
  • G02B6/4415—Cables for special applications
  • G02B6/4427—Pressure resistant cables, e.g. undersea cables
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02B—BOARDS, SUBSTATIONS OR SWITCHING ARRANGEMENTS FOR THE SUPPLY OR DISTRIBUTION OF ELECTRIC POWER
  • H02B7/00—Enclosed substations, e.g. compact substations
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
  • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
  • H02H3/02—Details
  • H02H3/05—Details with means for increasing reliability, e.g. redundancy arrangements
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
  • H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
  • H02H7/26—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured
  • H02H7/268—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured for dc systems
• • 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

• This invention generally relates to the field of electrical substations and, more particularly, to subsea electrical substations powered and controlled from topside facilities.
• Subsea electrical substations are often required for large electrical power consumption subsea hydrocarbon production fields located in deep water.
• the subsea electrical substations are many kilometers from a source of electrical power.
• the maintenance related difficulties presented to subsea electrical substations become more burdensome in Arctic applications.
• the Arctic conditions often make it nearly impossible to access the subsea electrical substation for maintenance for months at a time due to ice cover.
• Deep water applications further require expensive recovery vessels to retrieve failed subsea electrical hardware.
• the second concept involves retrievable electrical control and protection modules which are installed subsea. Electrical control power is typically derived from subsea installed control power transformers, battery packs or complex uninterruptible power supplies. This design often requires a ship based remotely operated vehicle (ROV) for control module maintenance and a complete removal of the subsea substation to service failed control power components. Again, there are a variety of disadvantages of being forced to retrieve the entire subsea station in the event repair is needed.
• ROV remotely operated vehicle
• the present invention provides a system and method for improving subsea substation reliability and availability.
• a power distribution system comprising: a power generator constructed and arranged to provide AC power, the power generator is located topside; a direct current power supply located topside; a control system located topside; an electrical substation located subsea, the electrical substation is electrically connected to the AC power provided by the power generator, the electrical substation comprises a plurality of circuit breakers and a circuit breaker operating system associated with each circuit breaker, the circuit breaker operating system is constructed and arranged to operate the associated circuit breaker; a bus assembly electrically connected to each circuit breaker; and a plurality of control modules positioned subsea, the control modules are electrically connected to the direct current power supply and communicatively connected to the control system, each control module is operatively connected to a circuit breaker operating system.
• Figure 1 is a block diagram of an electrical system according to one embodiment of the present disclosure.
• Figure 2 is a block diagram of an electrical substation according to one embodiment of the present disclosure.
• Figure 3 is a block diagram of the communicative connection between circuit breaker operating systems and breaker control and protection modules according to one embodiment of the present disclosure.
• Figure 4A is a cross-sectional view of a power and communications umbilical according to one embodiment of the present disclosure.
• Figure 4B is an exploded cross-sectional view of the auxiliary power and communications cable depicted in Figure 4A.
• Figure 5 is a flowchart showing the basic steps of retrieving a breaker control and protection module according to one embodiment of the present disclosure.
• Embodiments of the present disclosure provide a modular and reliable electrical substation, or subsea switchgear, designed to operate without intervention for extended periods of time.
• the substation can be subsea 36kV class switchgear.
• the switchgear power devices can consist of standard circuit-breakers, low power type instrument transformers and insulated bus bar assemblies.
• the switchgear components can be housed in a pressurized enclosure.
• the enclosure can be, but is not limited to, gas or oil filled. In one embodiment, the enclosure is filled with SF 6 gas.
• control and protection electronics for each circuit breaker can be housed in separately recoverable modules rather than the enclosure housing the circuit breaker operating mechanism. Such a configuration assists in decreasing the mean time to repair in the event the substation or associated equipment needs to be serviced, thereby leading to enhanced functional availability of the substation.
• control and protection electronics in each module can be constructed and arranged to automatically protect and control an adjacent circuit breaker along with its primary circuit breaker which also enhances the reliability availability of the power supply to the loads.
• the redundant configuration of the control and protection module allows any module to be replaced without losing control of the associated circuit breaker.
• the availability of power to the load is maintained even during the short time required to replace the module.
• auxiliary power can be provided to the substation from the shore station (or other source supply).
• the auxiliary power can be provided by means of redundant direct current cables integrated in an umbilical (i.e., submarine power cable).
• the HV DC can be stepped down before being delivered to the control and protection systems. By independently powering the control system, the status of each circuit breaker can be monitored and controlled during a black start without the need for a complex subsea battery supplied uninterruptible auxiliary power system.
• Embodiments of the overall system can include a communication system.
• the communicative link between the switchgear module and the shore station can be made via redundant fiber optic cables also integrated into the umbilical.
• the communicative link can also be provided in a separate communications line.
• a remote control and monitoring system allows for a reconfiguration of the electronic devices thus making it possible to adapt the power system operation to current conditions at the subsea site.
• Figure 1 is a block diagram of a power distribution system 100 according to one embodiment of the present disclosure. As depicted, the power distribution system 100 includes a generator 101 constructed and arranged to generate high voltage AC power, a DC power supply 103 constructed and arranged to provide high voltage DC power, and a control system 105.
• HV DC voltage is between 2kV and lOkV, though other voltages may be appropriate depending on design objectives and system configuration.
• the output of generator 101, DC supply 103 and control system 105 are provided to a topside umbilical termination assembly (UTA) 107.
• UTA 107 is the interface between the topside equipment and the main umbilical 109. It is the main umbilical 109 which provides HV AC, HV DC and a communications line from the topside, through the waterline 1 1 1, and to a subsea substation 121.
• topside means above the waterline.
• a subsea UTA 113 is provided to separate the various cables bundled within the umbilical 109. More particularly, a HV AC cable 115, a HV DC cable 117 and a communication cable 119 are provided to the substation 121 and its associated equipment
• FIG. 2 is a block diagram of an electrical substation 121 according to one embodiment of the present disclosure.
• electrical substation 121 houses two circuit breakers 201, 203.
• the circuit breakers 201, 203 are electrically connected to bus 205.
• the electrical substation may include more circuit breakers depending on the design objectives and needs of the overall electrical system.
• These high voltage components are housed within an enclosure 207.
• the HV AC power equipment in the substation is constructed and arranged to operate within a gas or oil-based insulation medium.
• Enclosure 207 can be filled with SF 6 gas, insulating oil, or other insulating media.
• the enclosure can have a pressure of 1.5 bar, though other pressures may be applied.
• Enclosure 207 may be constructed of a variety of materials, such as, but not limited to steel. For example, S3S5J2, P500QL2 and 80HLES steels can be utilized for the construction of enclosure 207.
• circuit breaker 201 functions as the incoming breaker.
• HV AC line 115 is connected at input 209.
• sensor devices are also provided for each circuit breaker in order to provide information to the control and electrical protection system.
• a non-contact voltmeter 211 and low power current transformer 213 are associated with each circuit breaker 201, 203.
• the voltmeters 211 and current transformers 213 are electrically and/or communicatively connected to sensor output terminals 215 and 217, respectively.
• Load connection 219 enables the HV AC to be delivered to a load in the event circuit breakers 201 and 203 are closed.
• each circuit breaker 201, 203 Associated with each circuit breaker 201, 203 is a circuit breaker operating system 221, 223, respectively.
• Each circuit breaker operating system 221, 223 is electrically connected to its associated circuit breaker.
• the circuit breaker operating systems have their own enclosure.
• the circuit breaker operating systems are enclosed at a relative pressure of 1.5 bar.
• the circuit breaker operating systems are filled in an N 2 atmosphere. In some embodiments, there is no pressure differential between the internal pressures of the HV AC enclosure and the circuit breaker operating system enclosure.
• each circuit breaker operating system 221, 223 has protection module connections 225.
• the circuit breaker operating systems have two protection module connections such that two independent protection modules may be electrically connected to the circuit breaker operating system.
• FIG. 3 is a block diagram of the communicative connection between circuit breaker operating systems 221, 223 and breaker control and protection modules 301, 303 according to one embodiment of the present disclosure.
• each breaker control and protection module (BCPM) 301, 303 is housed separately from substation 121.
• Each BCMP 301, 303 has three input connections 305 and two output terminals 307. With respect to the input connections, each BCPM is connected to the HV DC line 117 and communications line 119. Additionally, each BCPM is connected to output of the voltmeters and current transformers associated with the associated circuit breakers) with which the BCPM controls and protects.
• connections to the switchgear and associated equipment and modules can be made via wet mate connectors.
• each BCPM 301, 303 may provide control and protection for multiple circuit breakers.
• Each BCPM houses the protection relay and power supplies required for correct operation of the associated circuit breakers).
• each circuit breaker can also be protected and controlled by the BCPM of an adjacent or separate circuit breaker.
• the redundant configuration provided in Figure 3 helps to enable a more reliable system.
• each BCPM provides "main" control to one CB operating system and "axillary" control to another CB monitoring system.
• BCPM 301 provides its main control to CB operating system 221 via control line 309.
• BCPM 301 also provides auxiliary control to CB operating system 223 via control line 311.
• BCPM 303 provides its main control to CB operating system 223 via control line 313.
• BCPM 303 provides auxiliary control to CB operating system 221 via control line 315.
• the BCPM has the same functionality regardless of its role as “main” or "auxiliary” control.
• the BCPMs are individually retrievable. In the event a BCPM must be retrieved for repair, the overall system can continue uninterrupted. As described herein, the protection, monitoring and control of the substation can be provided by an adjacent BCPM without any modifications to the configuration of the substation or BCPM during the retrieval process. Because the trip and close coils of the CB operating systems have a dedicated power supply, they can be switched on and off remotely from the shore station or topside control system.
• each BCPM can autonomously monitor a variety of conditions, such as, but not limited to, the circuit breaker output current. In the event a parameter exceeds a predefined value, the BCPM trips the breaker off through power or communication provided through a control line.
• the trip values can be configured from the topside control system or station.
• each circuit breaker can be effectively protected by two BCPMs. In such a configuration, both BCPMs will race to trip the breaker off via independent trip coils should an over current, or other event, occur.
• each BCPM 303 can be in constant communication with the topside control system.
• the BCP will continuously, periodically, or upon command report information to the topside control system.
• the information report can comprise the status of the breaker current, breaker position and health of the BCPM, such as the breaker trip spring charge. From the surface via the BCPM, the breaker can be commanded to open or close and/or the trip spring can be commanded to be charged.
• FIG 4A is a cross-sectional view of a power and communications umbilical 109 according to one embodiment of the present disclosure.
• umbilical 109 is surrounded by a main sheath 401.
• Main sheath 401 is constructed and arranged to withstand the stresses typically encountered in subsea conditions.
• three HV AC lines 403 are provided.
• three auxiliary power and communication cables 405 are provided. Though three auxiliary power and communication cables 405 are depicted, other embodiments can have fewer or more.
• Support structures 407 can also be provided to support the overall rigidity of umbilical 109 and/or maintain the placement of auxiliary power and communication cables 405.
• Figure 4B is an exploded cross-sectional view of the auxiliary power and communications cable 405 depicted in Figure 4A.
• Auxiliary power and communication cables 405 include a sheath 409, an outer coaxial conductor 411, insulator 413, inner coaxial conductor 415 and a fiber optic line 417.
• the auxiliary power and communication cables 405 are provided in order to provide communications and DC power to the BCPMs.
• a coaxial configuration is shown to reduce coupling with the main AC conductors 403.
• the outer coax conductor 411 and inner coax conductor 415 can be sized such that the electrical resistance is not more than 1 ⁇ km.
• the conductors are constructed and arranged to operate at lOkV DC.
• a plurality of optical fibers comprise fiber optic line 417.
• FIG. 5 is a flowchart showing the basic steps of retrieving a breaker control and protection module according to one embodiment of the present disclosure.
• Process 500 begins by identifying the BCPM that must be removed (block 501).
• the BCPM can be identified via communication to the topside control system.
• the BCPM may be removed due to identification of a malfunction, periodical repair, etc.
• the identification can be based on information received from monitoring devices related to each circuit breaker within the substation.
• the monitoring devices can be, but are not limited to, voltmeters and/or current transformers.
• the control system confirms that the adjacent BCPM has control of the circuit breaker which is primarily controlled by the BCPM to be removed (block 503). Once confirmation has been received, CB control of the BCPM is disabled (block 505). Next, the DC supply to the BCPM is disconnected (block 507). The communication and sensor lines are also disconnected (block 509). Upon successful disconnection of the necessary lines, a remote operated vehicle (ROV) or other appropriate device can be used to remove the BCPM (block 511).
• ROV remote operated vehicle
• hydrocarbon management or “managing hydrocarbons”” includes hydrocarbon extraction, hydrocarbon production, hydrocarbon exploration, identifying potential hydrocarbon resources, identifying well locations, determining well injection and/or extraction rates, identifying reservoir connectivity, acquiring, disposing of and/ or abandoning hydrocarbon resources, reviewing prior hydrocarbon management decisions, and any other hydrocarbon-related acts or activities.
• hydrocarbon management is also used for the injection or storage of hydrocarbons or C0 2 , for example the sequestration of CO2, such as reservoir evaluation, development planning, and reservoir management.
• the disclosed methodologies and techniques may be used to extract hydrocarbons from a subsurface region.
• embodiments described herein can be used to power equipment associated with hydrocarbon production or extraction.
• the equipment and techniques used to drill a well and/or extract the hydrocarbons are well known by those skilled in the relevant art.
• Other hydrocarbon extraction activities and, more generally, other hydrocarbon management activities, may be performed according to known principles.
• a power distribution system comprising: a power generator constructed and arranged to provide AC power, the power generator is located topside; a direct current power supply located topside; a control system located topside; an electrical substation located subsea, the electrical substation is electrically connected to the AC power provided by the power generator, the electrical substation comprises a plurality of circuit breakers and a circuit breaker operating system associated with each circuit breaker, the circuit breaker operating system is constructed and arranged to operate the associated circuit breaker; a bus assembly electrically connected to each circuit breaker; and a plurality of control modules positioned subsea, the control modules are electrically connected to the direct current power supply and communicatively connected to the control system, each control module is operatively connected to a circuit breaker operating system.
• the electrical substation further comprises at least one monitoring device associated with each circuit breaker, the monitoring device is constructed and arranged to detect the status conditions of the associated circuit breaker.
• the power distribution system of paragraph Al wherein the status conditions may be selected from a group consisting of circuit breaker current, circuit breaker position and health of the protection module.
• control system is communicatively connected to the control module by a fiber optic cable.
• a method of servicing a power distribution system comprising: providing the power distribution system comprising: a power generator constructed and arranged to provide AC power, the power generator is located topside; a direct current power supply located topside; a control system located topside; an electrical substation located subsea, the electrical substation is electrically connected to the AC power provided by the power generator, the electrical substation comprises a plurality of circuit breakers and a circuit breaker operating system associated with each circuit breaker, the circuit breaker operating system is constructed and arranged to operate the associated circuit breaker; a bus assembly electrically connected to each circuit breaker; and a plurality of control modules positioned subsea, the control modules are electrically connected to the direct current power supply and communicatively connected to the control system; identifying a first control module to be removed, the first control having control over a first circuit breaker operating system; disconnecting the first control module from the direct current power supply and control system; and removing the first control module from its subsea location.
• the electrical substation further comprises at least one monitoring device associated with each circuit breaker, the monitoring device is constructed and arranged to detect the status conditions of the associated circuit breaker.

Landscapes

• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Manufacturing & Machinery (AREA)
• Remote Monitoring And Control Of Power-Distribution Networks (AREA)
• Direct Current Feeding And Distribution (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=51792600

Family Applications (1)

Country Status (5)

Cited By (1)

Families Citing this family (3)

Citations (5)

Family Cites Families (6)

• 2013
  • 2013-04-19 EP EP13781321.8A patent/EP2842205A4/de not_active Withdrawn
  • 2013-04-19 WO PCT/US2013/037453 patent/WO2013163043A1/en active Application Filing
  • 2013-04-19 EA EA201491981A patent/EA029463B1/ru not_active IP Right Cessation
  • 2013-04-19 CA CA2868111A patent/CA2868111C/en active Active
• 2014
  • 2014-09-22 DK DK201400539A patent/DK201400539A1/da not_active Application Discontinuation

Patent Citations (5)

Non-Patent Citations (2)

Also Published As

Similar Documents

Legal Events