System and method for retrofitting a power generation system to incorporate clutchless synchronous advance

Abstract

To provide a system and a method for retrofitting a power generation system to incorporate clutchless synchronous condensing.SOLUTION: A system includes a clutchless synchronous condensing coupling (16) configured to couple a turbine shaft (52) of a gas turbine system (12) to a generator shaft (64) of a synchronous generator (14) of a power generation system (10). The clutchless synchronous condensing coupling (16) includes a first coupling portion (87) configured to couple to the turbine shaft (52), and a second coupling portion (91) configured to couple to the generator shaft (64). The clutchless synchronous condensing coupling (16) is configured to allow the power generation system (10) to operate in an active power mode and a reactive power mode without a clutch assembly (13).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates generally to power generation systems having generators driven by gas turbine engines, and more particularly to synchronous advance. [Background technology]

[0002] Power generation systems often include a clutch assembly between a generator and a gas turbine system. The clutch assembly enables selective engagement and disengagement between the generator shaft and the gas turbine system. However, the clutch assembly can increase costs associated with power generation system repairs, replacement parts, and downtime. Unfortunately, the clutch assembly may be installed on an existing power generation system where the gas turbine system and generator are already mounted in a set position on a foundation (i.e., an existing footprint), and the control system is specifically designed for various operating modes using the clutch assembly. There is a need for a system and method for retrofitting an existing power generation system to operate without the clutch assembly while enabling various operating modes of the power generation system (e.g., an active power mode with a synchronous generator operating to generate power for the power grid and a reactive power mode with a synchronous generator operating as a synchronous advanced machine to stabilize the power grid). In particular, there is a need for such a retrofit that does not require substantial modifications to the existing footprint, i.e., does not require any substantial movement of the gas turbine system and generator from their set position on the foundation. Summary of the Invention

[0003] Certain embodiments commensurate in scope with the originally claimed subject matter are summarized below. These embodiments are not intended to limit the scope of the disclosure; rather, these embodiments merely provide a brief summary of some disclosed embodiments. Indeed, the disclosure may encompass a variety of forms that may be similar to or different from the embodiments set forth below.

[0004] According to one embodiment, a system includes a clutchless synchronous advance coupling configured to couple a turbine shaft of a gas turbine system to a generator shaft of a synchronous generator of a power generation system, the clutchless synchronous advance coupling including a first coupling portion configured to couple to the turbine shaft and a second coupling portion configured to couple to the generator shaft, the clutchless synchronous advance coupling configured to enable the power generation system to operate in active power and reactive power modes without a clutch assembly.

[0005] According to one embodiment, a power generation system includes a gas turbine system, a synchronous generator, a clutchless synchronous advance coupling, a plurality of bearings, and a sump discharge system. The gas turbine system includes a compressor, a combustor configured to generate a combustion gas flow, a first turbine driven by the combustion gas flow, and a second turbine driven by the combustion gas flow downstream from the first turbine. A first shaft of the first turbine is not rotatably coupled to a second shaft of the second turbine. The synchronous generator is configured to operate in an active power mode and a reactive power mode. The clutchless synchronous advance coupling is provided to couple the second shaft to a generator shaft of the synchronous generator. The clutchless synchronous advance coupling is configured to transfer torque from the second shaft to the generator shaft to drive the synchronous generator in the active power mode to supply active power to a power grid. The clutchless synchronous advance coupling is configured to transfer torque from the generator shaft to the second shaft to generate reactive power or absorb reactive power when the synchronous generator is operating as a synchronous advance machine in the reactive power mode. The plurality of bearings are configured to support a first shaft, a second shaft, a generator shaft, or a combination thereof. The sump drain system is configured to operate in a first mode during a real power mode and in a second mode during a reactive power mode, and the sump drain system is configured to channel lubricant to the plurality of bearings.

[0006] According to one embodiment, a method for retrofitting a power generation system includes removing a clutch assembly between a synchronous generator downstream of a first turbine and a second turbine of a gas turbine system, wherein a first shaft of the first turbine is not rotatably coupled to a second shaft of the second turbine. The method also includes installing a clutchless synchronous advance coupling coupling the first shaft and a generator shaft of the synchronous generator. The method further includes installing a controller or updating an existing controller to operate the power generation system in active power and reactive power modes using the clutchless synchronous advance coupling without the clutch assembly.

[0007] These and other features, aspects, and advantages of the present disclosure will be better understood from the following detailed description when read in conjunction with the accompanying drawings, in which like characters represent like parts throughout. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram of an embodiment of a power generation system having a clutchless synchronous advance module that replaces a clutch assembly in accordance with an embodiment of the present disclosure. FIG. [Figure 2] 2 is a schematic diagram of an embodiment of a power generation system retrofitted with the clutchless synchronous advance module shown in FIG. 1. [Figure 3] 3 is a side view of one embodiment of the clutchless synchronous phase advance module 11 shown in Figures 1 and 2. [Figure 4] 4 is a flow chart of one embodiment of a process for retrofitting a power generation system to incorporate the clutchless synchronous advance module shown in FIGS. 1-3. [Figure 5] 1 is a flow chart of one embodiment of a process for updating the operation of a sump discharge system as part of retrofitting a power generation system to incorporate a clutchless synchronous advance module. DETAILED DESCRIPTION OF THE INVENTION

[0009] One or more specific embodiments of the present disclosure are described below. To provide a concise description of these embodiments, all features of an actual implementation may not be described herein. It should be appreciated that in the development of any such actual implementation, such as any engineering or design project, many implementation-specific decisions must be made to achieve the developer's particular goals, such as compliance with system-related and business-related constraints, which may vary from implementation to implementation. Moreover, it should be appreciated that such a development effort may be complex and time-consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill in the art having the benefit of this disclosure.

[0010] When introducing elements of various embodiments of the present disclosure, the articles "a," "an," and "the" are intended to mean that there are one or more of the element. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements. Furthermore, references to "one embodiment" or "embodiments" of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.

[0011] The disclosed embodiments provide systems and processes for retrofitting a power generation system to incorporate a clutchless synchronous advance system. As described in detail below, retrofitting an existing power generation system may include removing a clutch assembly from the power generation system and replacing the clutch assembly with a clutchless synchronous advance coupling configured to couple a generator shaft of a synchronous generator to a turbine shaft of a gas turbine engine. Additionally, retrofitting an existing power generation system may include further modifications and updates to the controller, sump discharge system (e.g., incorporation of a pump), and other systems.

[0012] FIG. 1 is a schematic diagram of an embodiment of a power generation system 10 having a clutchless sync advance module 11 disposed between a gas turbine system 12 (or gas turbine engine) and a synchronous generator 14 (or generator / phase advance machine). As described in detail below, the clutchless sync advance module 11 includes a clutchless sync advance coupling 16 (e.g., a rotary coupling). The clutchless sync advance module 11 may be designed as part of a retrofit kit for a previously installed power generation system 10 and / or as part of the original equipment (e.g., part of the overall power generation system 10). As part of a retrofit kit, the clutchless sync advance module 11 is configured to add clutchless sync advance capability to a previously installed power generation system 10 (e.g., having a clutch and / or not having sync advance capability) by replacing the clutch assembly module 13 with the clutchless sync advance module 11. In some embodiments, the clutchless synchronous advance module 11 is designed to fit into the same space previously occupied by the clutch assembly 13, thereby avoiding changes to the final operating positions of other major components of the power generation system 10.

[0013] The gas turbine system 12 may include a compressor section having one or more compressors or compressor stages 18, a combustor section having one or more combustors 20, and a turbine section having one or more turbines or turbine stages 22. The gas turbine system 12 and the synchronous generator 14 may be disposed within a power generation system housing 24. The power generation system housing 24 may be secured to a foundation 26. The power generation system housing 24 may include housing sections for each component of the gas turbine system 12. For example, the power generation system housing 24 may have a compressor housing section 28 configured to house the compressor 18, a combustor housing section 30 configured to house the combustor 20, and a turbine housing section 32 configured to house the turbine 22. In some embodiments, the various housing sections of the power generation system housing 24 may be configured to house multiple components of the gas turbine system 12. The power generation system housing 24 may also include or house other components such as an air intake system 34, a controller, a turbine ventilation system 36 (e.g., one or more fans in a ventilation duct) for the gas turbine system 12, a generator ventilation system 38 (e.g., one or more fans in a ventilation duct) for the synchronous generator 14, a filter assembly having one or more filters 40 in the air intake system 34, an exhaust stack 42, an engine lubrication system, a starting system, a hydraulic system, power and data, or some combination thereof.

[0014] In some embodiments, a previously installed power generation system 10 may be retrofitted by removing a previously installed connection (e.g., clutch assembly 13) between the turbine 22 and the synchronous generator 14 and replacing the clutch assembly 13 with the clutchless synchronous advance module 11, without significantly altering the installed positions of the housing 24, gas turbine system 12, and synchronous generator 14 on the foundation 26. In other words, the gas turbine system 12 and synchronous generator 14 can remain in their installed positions on the foundation 26, and the clutchless synchronous advance module 11 fills the space previously occupied by the clutch assembly 13. In some embodiments, the clutchless synchronous advance module 11 may be specifically sized to fit into the space occupied by the clutch assembly 13, and the clutchless synchronous advance module 11 may have a base size combined with a size adjustment mechanism that allows for a proper fit between the turbine 22 and the synchronous generator 14. For example, the clutchless synchronous advance module 11 may include adjustable housing panels to increase and / or decrease the height, width, or length of the module 11 depending on the available space. As a further example, the clutchless synchronous advance module 11 may include an adjustable mechanism on the clutchless synchronous advance coupling 16, such as an axial adjustment assembly on the coupling 16 and / or associated shaft. The axial adjustment assembly on the coupling 16 may allow for adjustment to increase or decrease the axial length of the clutchless synchronous advance coupling 16 and its associated shaft. For example, the axial adjustment assembly may include a resilient connection, an expandable / contractible shaft section, a spacer, or any combination thereof. In this manner, the size adjustment mechanism helps to enable the clutchless synchronous advance module 11 to be efficiently installed within the available space previously occupied by the clutch assembly 13. The overall footprint of the power generation system 10 generally remains the same even though the clutchless synchronous advance module 11 replaces the clutch assembly 13.By fitting the clutchless synchronous advance module 11 within the same space as the clutch assembly 13, the disclosed embodiments enable more efficient retrofits that substantially reduce downtime of the power generation system 10. In contrast, without the disclosed embodiments, the retrofit procedure could require time-consuming and costly relocation of the synchronous generator 14, the gas turbine system 12, and / or the enclosure 24 on the foundation 26, and / or resizing of the foundation 26.

[0015] Embodiments of the retrofit procedure may include removing and / or opening a portion of the power generation system housing 24 (e.g., a clutch casing or clutch housing portion 44) at the location of the clutch assembly 13 between the gas turbine system 12 and the synchronous generator 14. Once access is gained, the clutch assembly 13 may be removed and replaced with the clutchless sync advance module 11 (including the clutchless sync advance coupling 16). In some embodiments, the clutch housing portion 44 is reinstalled after installation of the clutchless sync advance module 11. In other embodiments, the clutchless sync advance module 11 has its own integral housing and is therefore self-contained and ready to operate when installed in the space previously occupied by the clutch assembly 13.

[0016] As described below, clutchless sync advance module 11 may include various auxiliary components 15, 17, 19, and 21 to support clutchless sync advance. For example, clutchless sync advance module 11 may include a controller 15 having a processor, a memory, and instructions stored in the memory and executable by the processor to perform various tasks associated with clutchless sync advance. In some embodiments, controller 15 may enable updating of a main controller (e.g., 78 in FIG. 2 ) of power generation system 10 to provide computer instructions suitable for implementing clutchless sync advance. Additionally, in some embodiments, controller 15 may enable local monitoring and / or control of clutchless sync advance module 11 (including clutchless sync advance coupling 16) and other components 17, 19, and 21. Component 17 may include, for example, all or a portion of a sump discharge system 72, which is described in further detail below with reference to FIG. 2 . Component 19 may include one or more sensors dedicated to monitoring aspects affecting clutchless synchronous advance, including, for example, sensors monitoring operating parameters of the power grid (e.g., grid frequency) and one or more operating parameters of synchronous generator 14, turbine 22, and / or clutchless synchronous advance coupling 16 (e.g., rotational speed, torque, vibration level, acoustic noise, rotating shaft alignment, or any combination thereof). Controller 15 and / or 78 controls operation of gas turbine system 12 in response to feedback from the one or more sensors to transition power generation system 10 between active and reactive power modes using clutchless synchronous advance coupling 16 without clutch assembly 13. Additionally, component 21 may include, for example, a user interface or control panel configured to enable adjustments to the operation of clutchless synchronous advance module 11.Components 15, 17, 19, and 21 may be communicatively coupled to one another and to a main controller (e.g., 78 in FIG. 2) of power generation system 10, thereby facilitating the completion of the retrofit of system 10 to incorporate clutchless synchronous advance.

[0017] FIG. 2 is a schematic diagram of one embodiment of a power generation system 10 retrofitted with the clutchless synchronous advance module 11 shown in FIG. 1 . The power generation system 10 includes a gas turbine system 12 coupled to a synchronous generator 14. The gas turbine system 12 includes a compressor 18, a combustor 20, and a turbine 22. In some embodiments, the gas turbine system 12 includes a high-pressure gas turbine (e.g., a core turbine 46) and a low-pressure gas turbine (e.g., a power turbine 48) disposed downstream from the core turbine 46. The core turbine 46 may be configured to drive a core shaft (e.g., a first turbine shaft 50), and the power turbine may be configured to drive a power shaft (e.g., a second turbine shaft 52). The first turbine shaft 50 may be physically separate from the second turbine shaft 52. That is, the first turbine shaft 50 is not mechanically connected to the second turbine shaft 52 and therefore does not mechanically drive the second turbine shaft 52.

[0018] The compressor 18 may be mechanically coupled to the first turbine shaft 50 (e.g., via the compressor shaft or a compressor shaft portion of the first turbine shaft 50) and configured to receive the incoming airflow 54 from the air intake system 34 of the power generation system 10. The first turbine shaft 50 may be supported by one or more bearings 56. The compressor 18 may include multiple compressor stages (e.g., 2 to 28 or more compressor stages), each having a plurality of stator vanes disposed about the compressor shaft and a plurality of compressor blades configured to rotate in response to rotation of the first turbine shaft 50. The compressor 18 may be configured to compress the incoming airflow 54 and deliver the compressed airflow 58 to the combustor 20.

[0019] The combustor 20 (including one or more fuel nozzles 57) may be configured to mix a compressed air flow 58 with a pressurized fuel flow 60 received from a fuel source and ignite the mixture to create a combustion gas flow 62. Although only a single combustor 20 is shown, the gas turbine system 12 may include multiple combustors. The combustor 20 may be configured to channel the combustion gas flow 62 to the core turbine 46. The core turbine 46 may include multiple turbine stages (e.g., 2 to 10 or more turbine stages), each having a plurality of stator vanes disposed about a first turbine shaft 50 and a plurality of turbine blades configured to rotate in response to rotation of the first turbine shaft 50. The combustion gas flow 62 may drive the rotation of the core turbine 46 and the first turbine shaft 50, but the core turbine 46 does not itself drive the rotation of the second turbine shaft 52. The core turbine 46 channels the combustion gas flow 62 (e.g., exhaust gases) exiting the core turbine 46 to the power turbine 48.

[0020] The power turbine 48 is mechanically coupled to the second turbine shaft 52 but not to the first turbine shaft 50. The power turbine 48 is configured to receive a combustion gas flow 62 (e.g., exhaust gases) from the core turbine 46. The second turbine shaft 52 may be supported by one or more bearings 56. The power turbine 48 may include a plurality of stator vanes disposed about the second turbine shaft 52 and a plurality of turbine blades coupled to the second turbine shaft 52 and configured to drive rotation of the second turbine shaft 52. The combustion gas flow 62 from the core turbine 46 may drive the power turbine 48 and generate mechanical work. The mechanical work generated by the power turbine 48 (i.e., due to the combustion gases 62 driving the rotation of the power turbine 48) may drive the synchronous generator 14 when the power generation system 10 operates in a real power mode (or a synchronous generation mode of the generator 14). That is, the mechanical work generated by the power turbine 48 may drive the second turbine shaft 52. The clutchless synchronous advance coupling 16 may be configured to couple the second turbine shaft 52 to the generator shaft 64 such that torque is transferred between the second turbine shaft 52 and the generator shaft 64. The torque from the second turbine shaft 52 is transferred to the generator shaft 64, causing it to rotate. The rotation of the generator shaft 64 drives the synchronous generator 14 such that the power turbine 48 can drive the synchronous generator 14 when the power generation system 10 operates in a real power mode (i.e., a synchronous generating mode).

[0021] The synchronous generator 14 may include a generator rotor 66 mounted within a generator stator 68. A generator shaft 64 is coupled to the generator rotor 66 and configured to rotate therewith. The generator shaft 64 may be supported by one or more bearings 56. The generator rotor 66 may be wound with a field winding, and the generator stator 68 may be wound with an armature winding. Thus, rotating the generator shaft 64 of the synchronous generator 14 can provide active power to the power grid 70 in an active power mode of the power generation system 10. As described above, the synchronous generator 14 is configured to be driven by the generator shaft 64 to provide active power in an active power mode. In a reactive power mode of the power generation system 10, the synchronous generator 14 operates as a synchronous lead machine in a synchronous lead mode to maintain a power factor on the power grid 70, as needed. The synchronous generator 14 may be configured to drive the generator shaft 64 in a reactive power mode to generate reactive power or to absorb reactive power in a reactive power mode to maintain a power factor on the power grid 70 in a reactive power mode. Thus, the synchronous generator 14 can operate as a synchronous generator 14 in active power mode and as a synchronous machine in reactive power mode. In reactive power mode, the synchronous generator 14 (operating as a synchronous machine in active power mode) is configured to rotate freely to regulate conditions on the power grid 70 while rotating the generator shaft 64 and the power turbine 48, but the free rotation of the synchronous machine does not drive the rotation of the core turbine 46 due to the lack of a mechanical connection between the core turbine 46 and the power turbine 48. Thus, synchronous advance is possible without the need for a clutch to selectively connect and disconnect the synchronous generator 14 and the turbine 22.

[0022] As described above, the one or more bearings 56 may be configured to support the first turbine shaft 50, the second turbine shaft 52, the generator shaft 64, the clutchless synchronous advance coupling 16, or some combination thereof. The sump drain system 72 may be configured to supply lubricant (e.g., oil) to the one or more bearings 56 as well as other portions of the power generation system 10. The sump drain system 72 may include an oil source 74 configured to store and / or supply lubricant for operation of the sump drain system 72. In some embodiments, the sump drain system 72 is configured to maintain a pressure differential across the one or more bearings 56 (e.g., bearing lubricant seals).

[0023] The sump drain system 72 can utilize internal pressure from the operation of the gas turbine system 12 to circulate the lubricant in active power mode. In active power mode, the core turbine 46 of the gas turbine system may be configured to operate above 8,000 RPM, which provides sufficient internal pressure for the sump drain system 72 to circulate the lubricant. However, during reactive power mode, the core turbine 46 may be shut down or operate at a substantially lower RPM (e.g., less than 2500 RPM). To maintain the circulation of the lubricant, the power generation system 10 includes a pump 76 (or multiple pumps) for the sump drain system 72 installed during a retrofit. In some embodiments, the pump 76 and / or the sump drain system 72 may be one of the components (e.g., component 17) of the clutchless synchronous advance module 11 (e.g., part of a packaged system), or the pump 76 may be separate and / or packaged with the sump drain system 72. The pump 76 may be configured to provide additional pressure to circulate the lubricant. In some embodiments, the pump 76 may be configured to operate only in reactive power mode. In some embodiments, the pump 76 may also be configured to supplement the internal pressure-driven circulation of lubricant during active power mode. In either case, however, the pump 76 may be part of a retrofit associated with the clutchless synchronous advance module 11. Additionally, the retrofit may include a controller update to enable operation of the pump 76 with the clutchless synchronous advance module 11.

[0024] The power generation system 10 may include a controller 78 configured to control the operation of the power generation system 10 (e.g., operate the system in an active power mode or a reactive power mode) via a processor 80 and a memory 82. The controller 78 may be a main controller and / or a controller separate from the above-described controller 15, and the controllers 15 and 78 may operate together to control various aspects of the power generation system 10; the controllers 15 and 78 may be integrated together as a single controller, or one or both of the controllers 15 and 78 may be configured to operate the power generation system 10 in an active power mode and a reactive power mode, including aspects specific to the clutchless synchronous advance module 11. Any control functionality described with respect to either the controllers 15 and 78 includes control functionality incorporated in one or both of the controllers 15 and 78. Thus, the following description of control functionality may refer only to the controller 78, but in some embodiments also covers the control functionality of the controller 78.

[0025] The processor 80 of the controller 78 may include one or more processing devices, and the memory 82 may include one or more tangible, non-transitory machine-readable media. By way of example, such machine-readable media may include RAM, ROM, EPROM, EEPROM, or optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of machine-executable instructions or data structures and that can be accessed by the processor 80 or other processor-based devices (e.g., mobile devices). In some embodiments, the memory 82 is configured to store controller instructions executable by the processor 80 to output various controller signals 84. For example, the processor 80 may execute the controller instructions to control the operation of the power generation system 10.

[0026] Controller 78 (via processor 80) and / or controller 15 (via the processor) can execute controller instructions to control operation of sump drain system 72. For example, controller 78 and / or 15 may be configured to stop pump 76 in an active power mode and operate pump 76 in a reactive power mode. In some embodiments, controller 78 and / or 15 may be configured to control operation of sump drain system 72 based at least in part on user input via a user interface, such as the user interface of component 21 of clutchless synchronous advance module 11 described above. The user interface may include an input / output device (e.g., a keyboard, a mouse, or a touch screen) configured to provide user input to controller 78 and / or 15. Additionally, the user interface may include a display (e.g., a computer monitor or personal device screen) configured to display user options for controller 78 and / or 15.

[0027] Additionally, controller 78 (or controller 15) may be configured to output various controller signals 84 via communications circuitry 86. Communications circuitry 86 may include wired and / or wireless communications circuitry. For example, communications circuitry 86 may include an antenna, wireless transceiver circuitry, and signal processing hardware and / or software (e.g., hardware or software filters, A / D converters, multiplexers, amplifiers), or combinations thereof, and may be configured to communicate over wireless communications paths via infrared (IR) wireless communications, satellite communications, broadcast radio, microwave radio, Bluetooth, Zigbee, Wi-Fi, UHF, NFC, etc.

[0028] In some embodiments, the controller 78 and / or 15 of the gas turbine system 12 is configured to maintain a minimum operating speed (e.g., revolutions per minute) of the first turbine shaft 50 and the core turbine 46 in the reactive power mode. Maintaining a minimum speed of the core turbine 46 can prevent windmilling of the core turbine 46 caused by rotation of the power turbine 48 disposed adjacent to the core turbine 46. In some embodiments, the core turbine 46 of the power generation system 10 is configured to operate between 1000 revolutions per minute (RPM) and 2500 RPM in the reactive power mode. In some embodiments, the core turbine 46 is configured to operate between 1500 RPM and 3000 RPM in the reactive power mode.

[0029] 3 is a side view of one embodiment of the clutchless synchronous advance module 11 shown in FIGS. 1 and 2. As described above, the module 11 having the clutchless synchronous advance coupling 16 is configured to replace the clutch assembly 13 as part of a retrofit for the power generation system 10. The clutchless synchronous advance coupling 16 may be configured to couple the second turbine shaft 52 to the generator shaft 64 such that torque may be transferred between the second turbine shaft 52 and the generator shaft 64. Specifically, the clutchless synchronous advance coupling 16 may be configured to transfer torque from the second turbine shaft 52 to the generator shaft 64 in a real power mode of the power generation system 10 and to transfer torque from the generator shaft 64 to the second turbine shaft 52 in a reactive power mode of the power generation system 10.

[0030] In some embodiments, a first coupling portion or first end 88 of the clutchless synchronous advance coupling 16 is configured to couple to the second turbine shaft 52. Additionally, a second coupling portion or second end 90 of the clutchless synchronous advance coupling 16 is configured to couple to the generator shaft 64. For example, the first end 88 may include a first flange 87 (e.g., an annular flange) coupled to a first mating flange 89 (e.g., an annular flange) by one or more fasteners 92, and the second end 90 may include a second flange 91 (e.g., an annular flange) coupled to a second mating flange 93 (e.g., an annular flange) by one or more fasteners 92. The fasteners 92 may include one or more removable fasteners, such as multiple threaded fasteners (e.g., threaded bolts, nuts, etc.), clamps, pins in slots, dovetails, or any combination thereof. Alternatively or additionally, the fasteners 92 may include one or more fixed or permanent joints, such as a welded joint. The connections between flanges 87 and 89 and flanges 91 and 93 may also include torque-transmitting mechanisms, such as teeth that mate with corresponding grooves (e.g., on opposing end faces of the flanges). For example, the torque-transmitting mechanisms may include hilt joints, diaphragm joints, grid joints, disk joints, or any combination thereof. In the illustrated embodiment, the torque-transmitting mechanisms include at least diaphragm joints 95 at the connections of flanges 87 and 89 and flanges 91 and 93.

[0031] The diaphragm coupling 95 of the clutchless synchronous advance coupling 16 may include a first diaphragm 94 disposed proximate the first end 88 of the coupling 16 and a second diaphragm 96 disposed proximate the second end 90 of the coupling 16. The first diaphragm 94 and the second diaphragm 96 may be configured to accommodate misalignment between the second turbine shaft 52 and the generator shaft 64. That is, the first diaphragm 94 and the second diaphragm 96 are configured to compensate for axial, radial, and angular offsets between the second turbine shaft 52 and the generator shaft 64. The first diaphragm 94 and the second diaphragm 96 may each be disposed within a respective portion of the clutchless synchronous advance coupling 16 and may include one or more flexible metal diaphragms, disks, or plates configured to flex during rotation of the second turbine shaft 52 and the generator shaft 64 to accommodate misalignment between the second turbine shaft 52 and the generator shaft 64. The diaphragms 94 and 96 of the diaphragm coupling 95 are configured to transmit torque from the outer diameter to the inner diameter and / or from the inner diameter to the outer diameter of the flexible metal diaphragms, disks, or plates. The diaphragm coupling 95 may include multiple straight diaphragms with a tapered profile having spokes and / or multiple convoluted diaphragms. The diaphragm coupling 95 of the clutchless synchronous advance coupling 16 may substantially reduce or eliminate maintenance compared to the clutch assembly 13. For example, the diaphragm joint 95 may not require any lubrication and may have a substantially longer lifespan than the clutch assembly 13, thereby avoiding potential downtime for repair or replacement. Thus, the diaphragm joint 95 may be considered lubricant-free, self-aligning or self-adjusting for misalignment between the shafts, and maintenance-free.

[0032] In the illustrated embodiment, clutchless sync advance module 11 includes a housing or framework 97 that supports and / or encloses clutchless sync advance coupling 16 having diaphragm coupling 95, two of components 15, 17, 19, and 21, a bearing 56 disposed around a portion of second turbine shaft 52, a bearing 56 disposed around a portion of generator shaft 64, and one or more lubricant supply conduits 99 configured to supply lubricant (e.g., oil) to bearing 56 (e.g., via system 72). Additionally, in some embodiments, housing or framework 97 of clutchless sync advance module 11 may support pump 76 and / or all of the additional components or sump discharge system 72 described above. While the illustrated embodiment of clutchless synchronous advance module 11 includes bearing 56, some embodiments of module 11 may exclude bearing 56, and / or housing or framework 97 may be sized based on the axial length of clutchless synchronous advance coupling 16, extending to flanges 87 and 91 and diaphragm coupling 95, as indicated by axial length 99. For example, axial length 99 of housing or framework 97 may be approximately 80-120%, 90-110%, or about 100% of the axial length of coupling 16. Housing or framework 97 may include an interior framework 101 surrounded by one or more outer housing panels 103, which may include one or more removable housing panels configured to facilitate installation and inspection. Module 11 may also include one or more installation / removal tools 105 (e.g., upper tooling and / or lower tooling), which may be configured to help raise and / or lower coupling 16, align coupling 16 with shafts 52 and 64, or any combination thereof. For example, tool 105 may include a motor-driven tool, a hydraulic tool, a pneumatic tool, or a combination thereof. Additionally, tool 105 may include mechanical supports (e.g., support bars, cables, chains, etc.), which may be moved into appropriate positions to support coupling 16 during installation and / or removal.These tools 105 may be packaged with the module 11 to facilitate efficient installation of the module 11 during a retrofit procedure. In some embodiments, the tools 105 may also be used to remove the clutch assembly 13. However, in some embodiments, the tools 105 may be excluded from the module 11.

[0033] FIG. 4 is a flowchart of one embodiment of a process 98 for retrofitting a power generation system 10 to incorporate the clutchless synchronous advance module 11 shown in FIGS. 1-3. For purposes of describing the process 98, the power generation system 10 and the clutchless synchronous advance module 11 are substantially the same as those described above with reference to FIGS. 1-3. For example, the retrofit steps of the process 98 may correspond to the retrofit shown in FIG. 1, in which the clutch assembly 13 is replaced with the clutchless synchronous advance module 11. Thus, the power generation system 10 includes a synchronous generator 14 configured to generate active power to the power grid in an active power mode, generate reactive power in a reactive power mode, or absorb reactive power in a reactive power mode to maintain a power factor on the power grid. The retrofit process is configured to enable clutchless synchronous advance operation of the power generation system 10.

[0034] The process 98 for retrofitting the power generation system 10 includes opening the power generation system's clutch casing 44 (block 100). The clutch casing 44 may be a portion of the power generation system housing 24. Opening the clutch casing 44 may include opening a side or top of the power generation system housing 24 located adjacent to the clutch assembly 13 to allow an operator performing the retrofit access to the clutch assembly 13. In some embodiments, the operator may open an existing opening via an access panel (e.g., a hinged panel).

[0035] The process 98 further includes removing the lubrication connection to the clutch assembly 13 to selectively couple the second turbine shaft 52 (e.g., of the power turbine 48) and the generator shaft 64 (block 102). However, the operator may leave the lubrication connection connected to one or more bearings 56 located proximate to the clutch assembly 13. The modified power generation system 10 may incorporate one or more bearings 56 to support the second turbine shaft 52, the generator shaft 64, or some combination thereof.

[0036] The process 98 includes removing the clutch assembly 13 from the clutch casing 44 (block 104). The clutch assembly 13 may include multiple clutch components, such as a flywheel, a pressure plate, a pressure spring, a release lever, a clutch housing, clutch plates, a clutch actuator, and a control, as well as other suitable components. Removing the clutch assembly 13 from the clutch casing 44 may include removing the clutch assembly 13 as an assembled unit or in the order of the components of the clutch assembly 13.

[0037] The process 98 includes installing the clutchless synchronous advance coupling 16 (e.g., the clutchless synchronous advance module 11) in the space previously occupied by the clutch assembly 13 (block 106). As discussed above, in some embodiments, the entire clutch assembly 13 is removed so that the clutchless synchronous advance coupling 16 (e.g., the module 11) can be installed in place between the second turbine shaft 52 and the generator shaft 64. As such, installing the clutchless synchronous advance coupling 16 (e.g., the module 11) may include directly attaching a first end 88 of the clutchless synchronous advance coupling 16 to the second turbine shaft 52 and directly attaching a second end 90 of the clutchless synchronous advance coupling 16 to the generator shaft 64. However, in other embodiments, one or more components of the clutch assembly 13 (i.e., that do not retain the functionality of a clutch) may remain attached to the second turbine shaft 52, the generator shaft 64, the housing 24, the foundation 26, or some combination thereof, particularly if those components are fixed in place and / or do not adversely affect the installation of the clutchless synchronous advance coupling 16 (e.g., module 11). In these embodiments, the first end 88 and / or the second end 90 of the clutchless synchronous advance coupling 16 may be configured to couple to one or more remaining components of the clutch assembly 13 (i.e., that do not retain the functionality of a clutch) that are attached to the second turbine shaft 52 and / or the generator shaft 64.

[0038] The process 98 includes providing updates (e.g., updated firmware or software instructions—controller updates) to the controller 78 for the power generation system 10 to perform clutchless synchronous advance (block 108). Providing the updates to the controller 78 may include providing updated sump drain system instructions to the controller (block 110). As described in more detail below, the updated sump drain system instructions may be configured to stop the pump 76 during an active power mode of the power generation system 10 and to operate the pump 76 during a reactive power mode of the power generation system 10.

[0039] Additionally, providing the update to the controller 78 may include providing a reactive power mode command to the controller 78 configured to control the gas turbine system 12 of the power generation system 10 during a reactive power mode (block 112). The reactive power mode command may be configured to maintain a minimum operating speed (e.g., revolutions per minute) of the turbine shaft in the reactive power mode to prevent a windmill condition of the core turbine 46. The reactive power mode command may be configured to operate the power generation system 10 between 1000 revolutions per minute (RPM) and 2500 RPM in the reactive power mode. In some embodiments, the reactive power mode command may be configured to operate the power generation system 10 between 1500 RPM and 3000 RPM in the reactive power mode. The reactive power mode command may be configured to operate the power generation system 10 at a predetermined RPM configured to prevent a windmill condition of the core turbine 46.

[0040] FIG. 5 is a flowchart of one embodiment of a process 114 for updating the operation of the sump drain system 72 as part of retrofitting the power generation system 10 to incorporate the clutchless synchronous advance module 11. For purposes of illustrating the process 114, the power generation system 10 and the clutchless synchronous advance module 11 are substantially the same as those described above with reference to FIGS. 1-3. For example, the retrofit steps of the process 114 may correspond to the retrofit shown in FIG. 2, in which the sump drain system 72 is modified to incorporate the pump 76. As described above, during the reactive power mode of the power generation system 10, the gas turbine system 12 may operate at a lower RPM than during the active power mode. As such, the gas turbine system 12 may provide a lower pressure to circulate oil through the sump drain system 72. In some embodiments, the pressure provided to the sump drain system 72 during the reactive power mode may be too low to fully circulate oil through the sump drain system 72, which may result in excess oil heating over time and creating residue that may clog the sump drain system 72. The process 114 for updating the operation of the sump drain system 72 may provide additional pressure to the power generation system 10 to properly circulate oil through the sump drain system 72 .

[0041] The process 114 includes installing a pump 76 in a fluid line between a lubricant source (e.g., an oil source) and a plurality of bearings 56 configured to support the first turbine shaft 50, the second turbine shaft 52, the generator shaft 64, or some combination thereof (block 116). The pump 76 may be a positive displacement pump configured to move lubricant (e.g., oil) from the oil source toward the plurality of bearings 56 and other lubricant flow paths through the gas turbine system 12 and / or the alternator 14. The pump 76 may be configured to provide sufficient pressure within the sump discharge system 72 to circulate the lubricant through the sump discharge system 72, the bearings 56, and the various lubricant flow paths.

[0042] The process 114 includes sealing the lubricant connections that were removed from the clutch assembly 13 (block 118). In some embodiments, at least some of the lubricant connections that were removed from the clutch assembly 13 may not be connected to the modified power generation system 10. If the lubricant connections are not connected, they may leak lubricant and cause a pressure drop within the sump drain system 72. Therefore, the method includes sealing the lubricant connections that were removed from the clutch assembly 13. The lubricant connections may be sealed via any suitable seal, for example, a cap, a plug, a welded joint, a crimp, or a combination thereof.

[0043] The process 114 further includes providing updated sump drain system instructions (e.g., updated firmware or software instructions—controller update) to the controller 78 (block 120). The updated sump drain system instructions may be configured to stop the pump 76 during an active power mode of the power generation system 10 and operate the pump 76 during a reactive power mode of the power generation system 10. As discussed above, the pressure provided to the sump drain system 72 during a reactive power mode may be too low to fully circulate oil through the sump drain system 72, which may result in excess oil heating over time and creating residue that may clog the sump drain system 72. Providing the sump drain system 72 with updated sump drain system instructions to operate the pump 76 in a reactive power mode may provide the power generation system 10 with enough additional pressure to properly circulate oil through the sump drain system 72.

[0044] While only certain features of the present disclosure have been illustrated and described herein, many modifications and changes will occur to those skilled in the art, and it is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention.

[0045] The techniques presented and claimed herein clearly improve the art and, as such, make reference to and apply to tangible objects and specific examples of a practical nature rather than abstract, intangible, or purely theoretical. Furthermore, if any claim appended at the end of this specification contains one or more elements designated as "means for [performing] [function]" or "steps for [performing] [function]," it is intended that such elements be construed under U.S. § 112(f). However, in the case of any claim containing elements designated in any other manner, it is intended that such elements not be construed under U.S. § 112(f). [Explanation of symbols]

[0046] 10 Power Generation System 11 Clutchless synchronous advance module 12 Gas Turbine System 13 Clutch Assembly Module 14 Synchronous generator 15 Controller, auxiliary components 16 Clutchless synchronous advance coupling 17 Auxiliary Components 18 Compressor or Compressor Stage 19 Auxiliary Components 20 Combustor 21 Components 22 Turbine or turbine stage 24 Power generation system enclosure 26 Basics 28 Compressor housing part 30 Combustor housing part 32 Turbine housing part 34 Intake system 36 Turbine ventilation system 38 Generator ventilation system 40 filters 42 Discharge Stack 44 Clutch housing part, clutch casing 46 Core Turbine 48 Power Turbine 50 First turbine shaft 52 Second turbine shaft 54 Airflow 56 Bearings 57 Fuel Nozzle 58 Compressed Air Flow 60 fuel flow 62 Combustion gas flow 64 Generator shaft 66 Generator rotor 68 Generator stator 70 Power grid 72 Sump discharge system 74 Oil source 76 Pump 78 Controller 80 processors 82 memory 84 Controller Signal 86 Communication Circuit 87 First flange 88 First coupling portion or first end 89 First mating flange 90 second connecting portion or second end 91 Second flange 92 Fasteners 93 Second mating flange 94 First Diaphragm 95 Diaphragm joint 96 Second diaphragm 97 Housing or framework 98 Process 99 Lubricant supply conduit 99 Axial length 101 Internal Framework 102 blocks 103 Outer housing panel 105 Installation / removal tools

Claims

1. 1. A system comprising: a clutchless synchronous advance coupling (16) configured to retrofit a power generation system (10) by coupling a turbine shaft (52) of a gas turbine system (12) and a generator shaft (64) of a synchronous generator (14) of the power generation system (10) in a space previously occupied by a clutch assembly (13), the clutchless synchronous advance coupling (16) comprising: a first coupling portion (88) having a first flange (87) configured to couple to a first mating flange (89) of the turbine shaft (52); a second coupling portion (90) having a second flange (91) configured to couple to a second mating flange (93) of the generator shaft (64); It is equipped with the clutchless synchronous phase-advance coupling (16) extends axially between a first coupling portion (88) and a second coupling portion (90); the clutchless synchronous advance coupling (16) comprises at least one diaphragm coupling (95); The clutchless synchronous advance coupling (16) is configured to enable the power generation system (10) to operate in active power and reactive power modes without a clutch assembly (13).

2. 2. The system of claim 1, further comprising a retrofit kit configured to retrofit the power generation system (10) previously equipped with the clutch assembly (13) to operate without the clutch assembly (13) in the active power mode and the reactive power mode, the retrofit kit comprising the clutchless synchronous advance coupling (16) and a controller (78) or instructions for updating an existing controller (78) of the power generation system (10) to implement clutchless synchronous advance.

3. 3. The system of claim 2, further comprising a pump configured to circulate the lubricant when the power generation system operates in the reactive power mode, and wherein the controller or instructions updating the existing controller of the power generation system are configured to operate the pump during the reactive power mode when pressure within the gas turbine system is insufficient to circulate the lubricant, and the pressure within the gas turbine system is sufficient to circulate the lubricant in the active power mode.

4. 2. The system of claim 1, comprising a clutchless synchronous advance module (11) having the clutchless synchronous advance coupling (16), the clutchless synchronous advance module (11) having a size adjustment mechanism configured to adjust the base size and the height, width or length of the clutchless synchronous advance module (11).

5. 2. The system of claim 1, wherein the clutchless synchronous advance coupling (16) is configured to fit into the space previously occupied by the clutch assembly (13), such that the gas turbine system (12) and the synchronous generator (14) remain in their installed positions on the foundation (26) of the power generation system (10).

6. 2. The system of claim 1, wherein the first coupling portion (88) comprises a first diaphragm coupling (95) of the at least one diaphragm coupling (95), the second coupling portion (90) comprises a second diaphragm coupling (95) of the at least one diaphragm coupling (95), and the first and second diaphragm couplings (95) are configured to accommodate misalignment between the turbine shaft (52) and the generator shaft (64).

7. 2. The system of claim 1, comprising the gas turbine system having a combustor configured to generate a combustion gas flow, a first turbine driven by the combustion gas flow, and a second turbine driven by the combustion gas flow downstream from the first turbine, wherein the first turbine and the second turbine are not mechanically connected, and the first coupling portion of the clutchless synchronous advance coupling is coupled to the turbine shaft of the second turbine.

8. 2. The system of claim 1, further comprising a framework (97) disposed around the clutchless synchronous advance coupling (16), the clutchless synchronous advance coupling (16) being configured to rotate within the framework (97).

9. 9. The system of claim 8, wherein the framework (97) includes one or more outer housing panels (103), one or more first bearings (56) for supporting the turbine shaft (52), one or more second bearings (56) for supporting the generator shaft (64), and one or more lubricant passages (99) to the one or more first bearings and the one or more second bearings.

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