Method for regulating and controlling supercritical liquefied petroleum gas fuel flow for gas turbine operation - Patents.com

Abstract

To provide a fuel conditioning and control system which provides dynamic control and steady state operations of a gas turbine fueled by supercritical liquefied petroleum gas (LPG).SOLUTION: A fuel conditioning and control system 10 comprises: a storage for LPG fuel; a fuel delivery sub-system 100 connecting the storage to turbomachinery; and a control system 20. A gas turbine 300 includes a gas turbine core control 206 that provides at least one piece of operational data of the gas turbine to the control system. The fuel delivery sub-system includes at least one sensor for sensing at least one property of the LPG fuel in the fuel delivery sub-system, the sensor providing data on the at least one property of the LPG fuel to the control system. The control system analyzes the data on the at least one property of the LPG fuel and at least one operational data of the gas turbine for dynamic control of the LPG fuel to the gas turbine under dynamic and steady state conditions.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates generally to fuel trimming and control systems. More particularly, the present disclosure relates to a fuel trimming system, a fuel control system and method for operating a gas turbine using liquefied petroleum gas (LPG) fuel in the supercritical phase. Summary of the Invention

[0002] A first aspect of the present disclosure provides a fuel regulation and control system that provides dynamic control and steady-state operation for a gas turbine supplied with liquefied petroleum gas (LPG). The fuel regulation and control system includes a reservoir for LPG fuel, a fuel delivery subsystem connecting the reservoir to the gas turbine, and a control system. The gas turbine includes a gas turbine core controller that provides at least one operational data of the gas turbine to the control system. The fuel delivery subsystem includes at least one sensor for sensing at least one property of the LPG fuel in the fuel delivery subsystem, the at least one sensor providing data related to the at least one property of the LPG fuel to the control system. The control system analyzes the data related to the at least one property of the LPG fuel and the at least one operational data of the gas turbine to control LPG fuel flow to the gas turbine under dynamic and steady-state conditions.

[0003] A second aspect of the present disclosure provides a liquefied petroleum gas (LPG) fuel preparation and delivery method that includes pumping liquid LPG fuel from a storage tank in a fuel delivery subsystem to a gas turbine, converting the liquid LPG fuel from the liquid LPG fuel to supercritical LPG fuel, sensing at least one characteristic of the LPG fuel in the fuel delivery subsystem, the sensing providing data related to the at least one characteristic of the LPG fuel to a control system, and controlling, by the control system, the conversion of the liquid LPG fuel from the liquid LPG fuel to supercritical LPG fuel in response to a fuel flow demand of the gas turbine for dynamic control and steady-state operation of the gas turbine to which the supercritical LPG fuel is provided.

[0004] A third aspect of the present disclosure provides a fuel regulation and control system for dynamic control and steady-state operation of a gas turbine supplied with liquefied petroleum gas (LPG). The fuel regulation and control system includes a storage unit for LPG fuel and a fuel supply subsystem connecting the storage unit to the gas turbine, the fuel supply system including a vaporizer / heat exchanger. The vaporizer / heat exchanger heats liquid LPG fuel supplied from the fuel supply subsystem to the vaporizer / heat exchanger to convert the liquid LPG fuel to supercritical LPG fuel, where the heat added to the vaporizer / heat exchanger is based on a function of the LPG fuel demand of the gas turbine. The control system includes a programmable logic controller (PLC). The fuel supply subsystem further includes a liquid fuel metering valve (LFMV), and the PLC and the LFMV are connected such that the PLC can provide operating instructions to the LFMV to control the flow of LPG fuel along the fuel supply subsystem. The gas turbine includes a gas turbine core controller that provides at least one operational data of the gas turbine to the control system. The fuel supply subsystem includes at least one sensor for detecting at least one characteristic of the LPG fuel in the fuel supply subsystem, and the at least one sensor provides data of the at least one characteristic of the LPG fuel to a control system. The control system analyzes the data regarding the at least one characteristic of the LPG fuel and at least one operational data of the gas turbine for dynamic control of LPG fuel flow to the gas turbine under dynamic and steady-state conditions. The at least one sensor for detecting the at least one characteristic of the LPG fuel in the fuel supply subsystem includes a plurality of pressure sensors, a plurality of temperature sensors, and an LPG fuel characterization instrument, for example, but not limited to, a gas chromatograph with chromatography capabilities, including a Wobbe index meter, and / or a gas calorimeter. The fuel supply subsystem further includes a low-pressure pump and a high-pressure pump in series, which increase the pressure of the LPG fuel in the fuel supply subsystem. The fuel supply subsystem includes an electric motor speed variation device, such as a variable frequency drive (VFD) or a switched reluctance (SR) motor, connected to at least the high-pressure pump.Since the PLC and the VFD / SR are connected, the PLC can provide operation commands to the VFD / SR to control the operation of at least the high pressure pump.

[0005] The exemplary aspects of the present disclosure are designed to solve the problems described herein and / or other problems not discussed.

[0006] These and other features of the present disclosure will be more readily understood from the following detailed description of the various aspects of the disclosure, taken in conjunction with the accompanying drawings which illustrate various embodiments of the present disclosure. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a block schematic diagram of a fuel trimming and control system according to an embodiment of the present disclosure. [Figure 2] FIG. 1 is a block schematic diagram of a control scheme for a fuel trimming and control system embodied by the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0008] It should be noted that the drawings of the present disclosure are not to scale. The drawings are intended to illustrate only typical aspects of the present disclosure and therefore should not be considered limiting of the scope of the present disclosure. In the drawings, like numbers represent like elements between the drawings.

[0009] As an initial matter, in order to clearly explain the current state of the art, it is necessary to select specific terminology when referring to and describing the relevant mechanical components within a power plant fuel conditioning and control system. Wherever possible, common industry terms are used and utilized consistent with their accepted meaning. Unless otherwise noted, such terms should be given a broad interpretation consistent with the context of this application and the scope of the appended claims. Those skilled in the art will recognize that in many cases, a particular component may be referred to using several different or overlapping terms. What may be described herein as being a single component may include, and be referred to in other contexts as consisting of multiple components. Alternatively, what may be described herein as comprising multiple components may be referred to elsewhere as a single component.

[0010] Additionally, several descriptive terms may be used regularly herein, and it will be helpful to define these terms at the beginning of this section. These terms and their definitions are as follows, unless otherwise stated: As used herein, "downstream" and "upstream" are terms that indicate a direction relative to the flow of a fluid, such as fuel, to a turbine engine or through one of the turbine's component systems. The term "downstream" corresponds to the direction of fluid flow, and the term "upstream" refers to the opposite direction of that flow.

[0011] Additionally, as noted below, certain descriptive terms may be used herein in a conventional manner: the terms "first," "second," and "third" may be used interchangeably to distinguish one component from another, and are not intended to denote the location or importance of the individual components.

[0012] The terms used herein are merely for the purpose of describing particular embodiments and are not intended to limit the disclosure. As used herein, the singular forms "a," "an," and "the" are intended to include the plural unless expressly stated otherwise. It will be further understood that the terms "comprise" and / or "comprising," as used herein, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or sets thereof. "Optional" or "optionally" means that the subsequently-stated event or circumstance may or may not occur, and the description includes instances in which the event occurs and instances in which it does not occur.

[0013] When an element or layer is referred to as being "on," "engaged," "connected," or "coupled" to another element or layer, it can be directly on, engaged, connected, or coupled to the other element or layer, or intervening elements or layers may be present. Conversely, when an element is referred to as being "directly on," "directly engaged," "directly connected," or "directly coupled" to another element or layer, there may not be intervening elements or layers. Other terms used to describe relationships between elements should be interpreted similarly (e.g., "between" versus "directly between," "adjacent to" versus "directly adjacent to," etc.). As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0014] 1 illustrates a fuel trim and control system 10 according to an embodiment of the present disclosure. The fuel trim and control system 10 includes a fuel delivery subsystem 100, a fuel and control system 20 including a programmable logic controller (PLC) 200, and a turbomachine including a gas turbine engine 300 (hereinafter "gas turbine").

[0015] In fuel regulating and control system 10, liquid LPG is first converted or conditioned to supercritical LPG and then may remain in such stage or be converted or conditioned to gaseous LPG based on the operating conditions and demands of fuel regulating and control system 10. The supercritical LPG is supplied downstream of gas turbine 300 via fuel supply subsystem 100. The downstream flow of LPG fuel through regulating and control system 10 is controlled by fuel and control system 20.

[0016] Fuel supply subsystem 100 includes a storage tank 102 for liquefied petroleum gas (LPG). As described herein, a series of conduits 104, 104L (for liquid fuel), 104SC (for supercritical fuel), and 104G (for gaseous fuel) interconnect the elements of fuel supply subsystem 100 and connect storage tank 102 to gas turbine 300. With respect to fuel supply subsystem 100, the flow of LPG is from storage tank 102, the most upstream component of fuel supply subsystem 100, to the end of fuel supply subsystem 100 downstream at gas turbine 300.

[0017] Conduit 104L connects storage tank 102 to low-pressure pump 106 and high-pressure pump 108. Low-pressure pump 106 and high-pressure pump 108 are used to draw liquid LPG from storage tank 102 and move the liquid LPG fuel through conduit 104L. Additionally, low-pressure pump 106 and high-pressure pump 108 increase the overall pressure on the liquid LPG fuel from storage tank 102 as it flows downstream through conduit 104L.

[0018] Additionally, as the liquid LPG fuel is withdrawn from the storage tank 102, the liquid LPG fuel stream travels downstream where it has various properties that are measured by at least one fuel property defining instrument, such as, but not limited to, a gas chromatograph or gas calorimeter (such as a Wobbe index meter), or a chromatography-mass spectrometer (GC / WIM) 126. In the GC / WIM 126, the properties of the liquid LPG fuel are provided to a programmable logic controller (PLC) 200 of the fuel and control system 20. The fuel composition defining component of the GC / WIM 126 functions to determine the constituent components of the liquid LPG fuel, including, but not limited to, aspects of qualitative and quantitative hydrocarbon composition, such as, but not limited to, heating value, relative density, vapor pressure, and motor octane number. The calorimeter or Wobbe index components of the GC / WIM 126 measure the liquid LPG fuel gas compatibility, the heating properties of the liquid LPG fuel, and the relative ability of the liquid LPG fuel to provide energy. Measurements from GC / WIM 126 are provided to PLC 200 through signal path 202. Signal path 202 can be any form of transmission of a signal from GC / WIM 126 (or any device in embodiments of the present disclosure that provides data). Signal path 202 carries data and information / commands back and forth between the fuel and elements connected to control system 20.

[0019] The fuel delivery subsystem 100 also includes an electric motor speed variation device, such as, but not limited to, a variable frequency driver (VFD) or switched reluctance (SR) motor (VFD / SR) 115 connected to the high-pressure pump 108. The VFD / SR 115 controls the operation of at least the high-pressure pump 108. In certain aspects of the embodiment, the VFD / SR 115 may control both the low-pressure pump 106 and the high-pressure pump 108. As described herein, the VFD / SR 115 controls the operation of at least the high-pressure pump 108 in response to signals from the PLC 200 via signal path 202. The VFD / SR 115 controls the operation of at least the high-pressure pump 108 to increase the pressure of the liquid LPG fuel downstream flow in the conduit 104L after the liquid LPG fuel flows from the high-pressure pump 108 to the pressure sensor 110PT0 and the temperature sensor 112TE0 (the subscript “0” denotes the “original” liquid LPG fuel from the storage tank 102).

[0020] From the low-pressure pump 106 and the high-pressure pump 108, the fuel delivery subsystem 100 further includes liquid LPG fuel flowing downstream in a conduit 104L that extends past a series of pressure and temperature sensors 110PT0 and 112TE0. The pressure and temperature sensors 110PT0 and 112TE0 measure the liquid LPG fuel after it passes through the pumps 106 and 108. The pressure and temperature sensors 110PT0 and 112TE0 provide liquid LPG characteristic information and feedback to the fuel and control system 20 and the PLC 200 via signal paths 202 (not all paths 202 are shown for ease of explanation, illustration, and understanding). Thus, the flow of liquid LPG fuel through the fuel regulation and control system 10 is managed and controlled. Both pressure sensor 110PT0 and temperature sensor 112TE0 include embedded transmitter-enabled components that allow liquid LPG property information and feedback to be transmitted to fuel and control system 20 and PLC 200 via signal path 202.

[0021] From the low-pressure pump 106 and the high-pressure pump 108, a fuel conduit 104L directs the liquid LPG flow downstream to a liquid fuel metering valve (LFMV) 114. As described herein, the LFMV 114 is controlled by a programmable logic controller (PLC) 200 to allow the liquid LPG fuel to flow in an amount that allows the liquid LPG fuel to be converted to supercritical LPG fuel in the vaporizer / heat exchanger 120. The LFMV 114 meters the downstream liquid LPG fuel flow and enables stable control of the flow rate. The LFMV 114 may include any configuration of metering valve now known or hereafter developed that enables metering of the liquid LPG fuel flow and stable control of the downstream liquid LPG fuel flow rate through the conduit 104L.

[0022] In the fuel delivery subsystem 100, from the LFMV 114, the liquid LPG fuel flows downstream through conduit 104L and to pressure sensor 116PT. L and temperature sensor 118TE L where "L" stands for "liquid" in liquid LPG fuel. L and temperature sensor 118TE L provides liquid LPG property information and feedback to the fuel and control system 20 and the PLC 200 via signal path 202. Thus, the downstream flow of liquid LPG fuel through the fuel regulation and control system 10 and the fuel delivery subsystem 100 is managed and controlled. L and temperature sensor 118TE L Both contain embedded transmitter-enabled components that allow liquid LPG fuel property information and feedback to be transmitted to the fuel and control system 20 and PLC 200 via signal path 202 .

[0023] Conduit 104L leads to a reactor or downstream vaporizer / heat exchanger 120 within fuel delivery subsystem 100. According to embodiments of the present disclosure, vaporizer / heat exchanger 120 of fuel delivery subsystem 100 can include any known or hereafter developed vaporizer / heat exchanger 120 configuration. Known or hereafter developed vaporizer / heat exchanger 120 configurations according to embodiments include at least non-expanding rigid walls that are sufficiently rigid to withstand high pressures within the vaporizer / heat exchanger 120. According to aspects of embodiments, vaporizer / heat exchanger 120 configurations within fuel delivery subsystem 100 can add heat to the contents of the vaporizer / heat exchanger 120. Heat can be added internally to the vaporizer / heat exchanger 120 or externally to the vaporizer / heat exchanger 120 and conducted through the walls via conventional thermodynamics. This applied heat source 140 can be derived from a power source such as, but not limited to, an electrical resistance or a heat tracking loop, and this heat source 140 can derive energy from an externally induced high temperature fluid flow such as, but not limited to, oil or water vapor (steam).

[0024] In the vaporizer / heat exchanger 120, heat is added to the liquid LPG fuel within the non-expansion confinement of the walls of the vaporizer / heat exchanger 120. Under basic thermodynamic principles at high temperatures without expansion, the liquid LPG fuel is subjected to a specific condition of pressure and temperature that is the liquid LPG fuel's critical point. When liquid LPG fuel is subjected to pressure and temperature higher than its critical point, the liquid LPG fuel becomes "supercritical." LPG fuel is "supercritical" when it is heated above its critical temperature and compressed above its critical pressure. In the supercritical region, LPG fuel exhibits certain supercritical properties and has behavior intermediate between that of a liquid and a gas. In particular, supercritical fluids (SCFs) have properties such as liquid-like density, gas-like viscosity, and diffusion values ​​intermediate between those of a liquid and a gas.

[0025] Additionally, the vaporizer / heat exchanger 120 of the fuel supply subsystem 100 is connected to the fuel and control system 20 and the PLC 200 along a signal path 202 to send and receive information. The vaporizer / heat exchanger 120 transmits information, such as the temperature and pressure of the vaporizer / heat exchanger 120, to the fuel and control system 20 and the PLC 200 via the signal path 202 to support the fuel and control system 20 and the PLC 200's control of the vaporizer / heat exchanger 120, as well as all of the regulation and control systems 10. In particular, the vaporizer / heat exchanger 120 provides information to the fuel and control system 20 and the PLC 200 regarding control and operating parameters for the VFD 115 and / or the LFMV 114. Additionally, the vaporizer / heat exchanger, depending on its operating principle, provides information to the PLC 200 to control the amount of heat added to the liquid LPG to convert the liquid LPG to supercritical LPG by adjusting the demand for heat coming from the heat source 140. This may be, but is not limited to, adjusting the electrical resistance or current through a heat trace, adjusting the flow of an incoming hot fluid such as, but not limited to, steam or oil.

[0026] The supercritical LPG fuel is now exiting the vaporizer / heat exchanger 120 in the fuel supply subsystem 100 into conduit 104SC. The supercritical LPG fuel is then detected by pressure sensor 122PT. SC and temperature sensor 124TE SC ("SC" stands for supercritical) flow downstream of another set of sensors. Pressure Sensor 122PT SC and temperature sensor 124TE SC The above set of sensors also provides LPG fuel property information and feedback to the fuel and control system 20 and PLC 200 through signal path 202. However, at this location in the fuel trim and control system 10 after the carburetor / heat exchanger 120, pressure sensor 122PT SC and temperature sensor 124TE SCprovides supercritical LPG fuel property information and feedback to fuel and control system 20 and PLC 200 via signal path 202. Thus, the flow of liquid LPG fuel through fuel regulation and control system 10, including fuel delivery subsystem 100, is controlled by pressure sensor 122PT. SC and temperature sensor 124TE SC , and as described herein, these sensors also include embedded transmitter-enabled components that allow for supercritical LPG fuel property information and feedback to be transmitted via signal path 202 to fuel and control system 20 and PLC 200 for control of fuel trimming and control system 10 and fuel delivery subsystem 100.

[0027] The supercritical LPG fuel flows downstream through conduit 104SC of fuel delivery subsystem 100, which includes at least one shut-off valve (SOV) 130 disposed in fuel and control system 20. SOV 130 can stop the flow of supercritical LPG fuel after the supercritical LPG fuel is produced. In one aspect of the embodiment, SOV 130 can be actuated to manually stop the flow of supercritical LPG fuel. Alternatively, any condition sensed by regulation and control system 10 can be detected by pressure sensor 110PT0, temperature sensor 112TE0, pressure sensor 116PT0, and pressure sensor 116PT1. L and temperature sensor 118TE L、 Pressure Sensor 122PT SC and temperature sensor 124TE SC , and / or pressure sensor 132PT SC and temperature sensor 134TE SCThe SOV 130 may terminate the flow of supercritical LPG fuel via a signal from the fuel and control system 20 if any of a series of sensors (described below) detects an abnormality. Additionally or alternatively, the SOV 130 may terminate the flow of supercritical LPG fuel within the fuel and control system 20 via a signal from the fuel and control system 20. According to certain aspects of the embodiment, the termination of LPG fuel may be due to any abnormal condition detected at any fuel delivery subsystem 100 by an element connected to the PLC 200 of the fuel and control system 20, including, but not limited to, the GC / WIM 126, the VFD / SR 115, the LFMV 114, the vaporizer / heat exchanger 120, and / or the heat source 140. Additionally, the SOV 130 may terminate the flow of supercritical LPG fuel within the fuel and control system 20 via a signal from the control system 20 due to any abnormal condition detected by the gas turbine (GT) subsystem 300 via the GT core control 206 (described below). Additionally, there may be multiple SOV 130 components in the fuel and control system 20 as necessary and justified by operational or safety related conditions.

[0028] As the supercritical LPG fuel flows downstream past the SOV 130 in the fuel and control system 20, the supercritical LPG fuel then passes through the pressure sensor 132PT. SC and temperature sensor 134TE SC ("SC" stands for supercritical). Similar to other sensors according to aspects of the present disclosure, pressure sensor 132PT SC and temperature sensor 134TE SC Each of the pressure sensors 132PT is connected to the fuel and control system 20 via a signal path 202. As described herein, the pressure sensor 132PT SC and temperature sensor 134TE SC Each of provides LPG fuel property information and feedback to the fuel and control system 20 and PLC 200 via signal path 202 so that the fuel and control system 20 can appropriately define and manage the flow of LPG fuel in liquid, gaseous, and / or supercritical states through the fuel conditioning and control system 10.

[0029] Supercritical LPG fuel is measured using a series of sensors, namely the pressure sensor 132PT SC and temperature sensor 134TE SC After passing through the supercritical LPG fuel in conduit 104SC, the supercritical LPG fuel in conduit 104SC flows downstream of a fuel control valve (FCV) 136 of the fuel and control system 20. As described herein, the FCV 136 can provide a controlled flow of supercritical LPG fuel at an appropriate rate as determined by the fuel and control system 20 in response to inputs from components of the fuel regulation and control system 10. The FCV 136 of the fuel delivery subsystem 100 can pass fuel according to the fuel demand required by the gas turbine 300 to operate under sensed operating conditions. The fuel demand required by the gas turbine 300 to operate under sensed operating conditions is provided by the gas turbine core control 206.

[0030] Further details of the gas turbine core control 206 and the sensed conditions of the gas turbine core control 206 are provided below. For ease of understanding, the gas turbine core control 206 senses conditions of the gas turbine 300 including, but not limited to, the compressor 306 discharge pressure, the compressor 306 speed, the combustion condition of the combustor 304, the low pressure turbine pressure, the combustor 304 pressure, the gas turbine speed, the load 310 demand, the power turbine 308 temperature and pressure, and other such gas turbine 300 operating variables now known or hereinafter determined. The sensed conditions provided by the gas turbine core control 206 in the sensed characteristics of the gas turbine 300 are provided to the flow control module 138 of the fuel and control system 20. In the fuel and control system 20, the sensed conditions are provided by the gas turbine core control 206 in the sensed characteristics of the gas turbine 300 and are provided to the flow control module 132 of the fuel and control system 20. SC and TE134 SCThe data (along with the supercritical pressure and temperature, which each provide, and the LPG fuel composition measured and defined by the GC / WIM 126) is analyzed and evaluated by the algorithm 210. Feedback can be provided to components of the fuel delivery subsystem 100 for enhanced dynamic operation, including dynamic operation based on real-time data. As used herein, dynamic operation includes operational changes required by the fuel and control system 20 analyzing and evaluating real-time data. In certain aspects of embodiments, components of the fuel delivery subsystem 100 that may provide feedback for enhanced dynamic operation include, but are not limited to, the low-pressure pump 106 and the high-pressure pump 108, the LFMV 114, the vaporizer / heat exchanger 120, data from the vaporizer / heat exchanger 120, the heat source 140, data from the heat source 140, and the FCV 136.

[0031] In the FCV 136 of the fuel and control system 20, the flow of supercritical LPG fuel is throttled to meet the LPG fuel demand downstream of the GT 300 in conduits 104G / 104SC (where "G" is for gaseous and "SC" is for supercritical). This fuel can be in either the gaseous or supercritical phase depending on the operating conditions from the GT 300. The gaseous / supercritical LPG fuel is supplied from conduits 104 / 104G / 104SC to the gas manifold 302 of the gas turbine 300. In the gas manifold 302, the gaseous / supercritical LPG fuel is distributed among all the fuel nozzles / premixers 312. In some cases, the gaseous / supercritical LPG fuel is mixed with compressed fluid (typically air) from the compressor 306 inside the fuel nozzles / premixers before entering the combustor 304. In some cases, gaseous / supercritical LPG fuel is mixed with compressed fluid (typically air) from compressor 306 in combustor 304. The gaseous / supercritical LPG fuel and compressed air are then ignited in combustor 304. The ignited and expanded gaseous / supercritical LPG fuel is channeled from combustor 304 to (gas) power turbine 308, where the rotational motion of gas power turbine 308 is transferred to rotor or shaft 309 / 311. Rotor or shaft 309 is mechanically connected from gas power turbine 308 to compressor 306 to rotate compressor 306. In some cases, rotor or shaft 309 may be separate from rotor or shaft 309 / 311, which is connected to load 310, and load 310 is driven by the rotation of rotor or shaft 309 / 311. Additionally, 309 / 311 may represent multiple shafts that may all rotate at different speeds depending on the design and operating principles of the gas turbine (GT) 300. The load 310 may be any suitable load, such as, but not limited to, a generator, a pump, another turbine, a machine, or any other load now known or hereafter developed.

[0032] 1 and 2, the interaction of fuel and control system 20 with components of fuel trim and control system 10 and fuel delivery subsystem 100 will now be described. As noted above, fuel and control system 20 includes PLC 200. PLC 200 includes, but is not limited to, pressure sensor 110PT0 and temperature sensor 112TE0, pressure sensor 116P TL and temperature sensor 118TE L , Pressure Sensor 122PT SC and temperature sensor 124TE SC and / or pressure sensor 132PT SC and temperature sensor 134TE SC 1, the GC / WIM 126, the VFD / SR 115 and the low pressure pump 106 and high pressure pump 108 via the VFD / SR 115, the LFMV 114, the vaporizer / heat exchanger 120, the heat source 140, and the SOV 130, the FCV 136, and the gas turbine 300 via the gas turbine core control 206. As mentioned above, signal path 202 interconnects the above-mentioned elements and components of fuel and control system 20 and fuel regulation system 10.

[0033] The fuel and control system 20 includes a PLC 200. The PLC 200 is a programmable logic controller configured to use the control of the fuel regulation system and control system 10. In one aspect of the embodiment, the PLC 200 may comprise a small modular device with limited input and output (I / O). In another aspect of the embodiment, the PLC 200 may comprise a larger device, and in another aspect, the PLC 200 may be networked with other PLCs and other systems in the power plant incorporating the fuel regulation system and control system 10. The PLC 200 provides flexible, rugged, and simple control with highly reliable automation in the harsh environment of the power plant. In an aspect of the embodiment, the PLC 200 may be any currently known or hereafter developed PLC.

[0034] The fuel and control system 20 includes a flow control module 138. As described herein, the flow control module 138 is coupled to the FCV 136 and receives data from the algorithm 210. The flow control module 138 is coupled to the FCV 136 and, in response to inputs from components of the fuel regulation and control system 10, controls the position of the FCV 136 to flow supercritical LPG fuel downstream of the fuel regulation and control system 10 at an appropriate rate as specified by the fuel and control system 20. In particular, the FCV 136 may pass fuel when the fuel demand determined by the gas turbine core controls 206 determines the fuel demand required by the gas turbine 300 to operate under detected conditions.

[0035] The flow control module 138 receives inputs from various components of the fuel delivery subsystem 100 within the fuel regulation and control system 10. The flow control module 138 is connected to an algorithm 210, which is a component of the fuel and control system 20. As shown in FIG. 2, the algorithm 210 receives inputs from the PLC 200, such as the fuel composition x produced by the GC / WIM 126. i Further, the algorithm 210 receives signals and data relating to the pressure sensor 110PT0 and the temperature sensor 112TE0, the pressure sensor 116PT L and temperature sensor 118TE L , Pressure Sensor 122PT SC and temperature sensor 124TE SC , and / or pressure sensor 132PT SC and temperature sensor 134TE SC The pressure p and temperature T signals and data from the series of sensors can be used by algorithm 210 as needed for system control purposes.

[0036] The algorithm 210 provides outputs of the specific gravity SG, the specific heat ratio k, and an estimate of the lower heating value reference LHV. The specific gravity SG and the specific heat ratio k are provided to the flow control module 138. The flow control module 138 also controls the PT 132. SC10. The pressure p1 provided by the FCV 136 may be provided, or for purposes of this disclosure, may be provided separately by any additional pressure sensor dedicated to providing this value to the flow control module 138. This pressure p1 represents the inlet pressure to the FCV 136 and, along with the specific gravity SG, the specific heat ratio k, the gas fuel temperature T, and the fuel demand from the gas turbine core control 206, is used to determine the valve position. Thus, the flow control module 138 of the fuel and control system 20 in conjunction with the PLC 200 of the fuel regulation and control system 10 can determine the position of the LFMV 114 of the fuel supply subsystem 100 for the fuel demand required by the gas turbine 300, which is provided from the gas turbine core control 206 to the flow control module 138 of the fuel and control system 20 and the PLC 200 of the fuel regulation and control system 10. Additionally, the flow control module 138 of the fuel and control system 20 in conjunction with the PLC 200 of the fuel regulation and control system 10 can determine the position of the FCV 136 due to the fuel demand required by the gas turbine 300 in relation to the supercritical conditions encountered in the FCV 136, where the fuel demand required by the gas turbine 300 is provided to the flow control module 138 of the fuel and control system 20 from the gas turbine core control 206.

[0037] Additionally, according to another aspect of the embodiment, the fuel and control system 20, including the flow control module 138 in conjunction with the PLC 200 and algorithm 210, can determine a preferred temperature or heat "Q" to add to the vaporizer / heat exchanger 120 from the heat source 140. By adding the determined preferred temperature or heat "Q" from the heat source 140 to the vaporizer / heat exchanger 120, the vaporizer / heat exchanger 120 can function at high efficiency to convert liquid LPG fuel to supercritical LPG fuel at the required temperature. The preferred temperature or heat "Q" added to the vaporizer / heat exchanger 120 from the heat source 140 can be determined as a function "f" of process variables, such as, but not limited to, temperature, pressure, and LPG flow demand. That is, Q=F(LPG demand). Furthermore, the temperature or heat "Q" added to the vaporizer / heat exchanger 120 can be determined as a function "f" of process variables, such as, but not limited to, specific volume v, specific heat c, and the like.p , absolute viscosity η, thermal conductivity λ and specific enthalpy h, critical temperature T c , and / or critical pressure p c Additionally, the temperature or heat "Q" may be determined based on the operating principles of the heat source 140 as a function of one or more operability variables, including, but not limited to, electrical resistance in the case of an electric heater, or heat conduction and convection parameters of an incoming hot fluid, such as steam or oil.

[0038] Additionally, the data can be utilized by the fuel and control system 20 to determine the desired real-time operating state of the fuel delivery subsystem 100 and its components. The real-time data defining the overall fuel regulation and control system 10 and the real-time operating state of the fuel delivery subsystem 100 allows the FCV 136 to be set to the desired position according to instantaneous and real-time values ​​using sensed fuel pressure, temperature, and composition, including those at the inlet of the FCV 136. The desired position of the FCV 136 allows for the passage of an appropriate amount of supercritical LPG to operate the gas turbine 300 under dynamic and steady-state conditions.

[0039] Accordingly, embodiments of the present disclosure provide a fuel trim and control system 10, a fuel and control system 20, and related methods for operating an LPG-fueled gas turbine in the supercritical phase. The embodiments include the fuel and control system 20 and associated algorithm 210-enabled software with supercritical LPG characteristics that provide dynamic gas turbine fuel control to the embodiments. Furthermore, the flow management of the fuel trim and control system 10 described herein can improve the durability of the fuel trim and control system 10 and fuel delivery subsystem 100 components that handle supercritical LPG fuel. Furthermore, with instruments such as gas chromatographs and calorimeters (e.g., Wobbe Index Meters, WIMs) that can evaluate thermodynamic fuel properties and LPG composition, the fuel trim and control system 10 and fuel delivery subsystem 100 can also dynamically adjust fuel flow automatically and in real time during gas turbine 300 operation.

[0040] As implemented in accordance with the present disclosure, the fuel trimming and control system 10 provides robustness to gas turbine operation by adding real-time data including, but not limited to, accurate values ​​for LPG density, specific heat ratio, superheat requirement, and mass diffusion ranges of liquid, gas, and supercritical phases. This real-time data can avoid trips caused by differences in fuel properties and, therefore, operational variations. Furthermore, the fuel trimming and control system 10 can accommodate operation of the gas turbine 300 using a variety of LPG fuel compositions, including, but not limited to, LPG fuels containing at least one of methane, ethane, hexane, pentane, propane, and butane.

[0041] In an embodiment, fuel conditioning and control system 10 transports liquid LPG fuel downstream from reservoir or storage tank 102 to gas turbine 300 while converting the liquid LPG fuel from a liquid state to a supercritical state. The flow of LPG fuel is within fuel delivery subsystem 100 and controlled by fuel and control system 20. Low-pressure pump 106 and high-pressure pump 108 provide motive force to the liquid LPG fuel to flow from storage tank 102 through conduit 104L. As described above, VFD / SR 115 drives high-pressure pump 108. VFD / SR 115 drives high-pressure pump 108 via a signal from fuel and control system 20. GC / WIM 126 obtains liquid LPG fuel composition information, including liquid LPG fuel gas compatibility, heating characteristics of liquid LPG fuel, and the relative ability of the liquid LPG fuel to provide energy, before the liquid LPG fuel travels through low-pressure pump 106 and high-pressure pump 108. After the low pressure pump 106 and the high pressure pump 108, the liquid LPG fuel flows downstream of a first set of sensors, which are pressure sensor 110PT0 and temperature sensor 112TE0. The flow of liquid LPG fuel is then metered and controlled by the LFMV 114, which may flow downstream as determined by the fuel and control system 20. After the LFMV 114, the liquid LPG fuel flows downstream of pressure sensor 116PT0. L and temperature sensor 118TE L The liquid LPG fuel then enters a reactor or vaporizer / heat exchanger 120, where heat is applied to the vaporizer / heat exchanger 120 by a heat source 140, heating the liquid LPG fuel to supercritical LPG fuel. The supercritical LPG fuel then flows downstream, again being detected by pressure sensor 122PT. SC and temperature sensor 124TE SC The pressure and temperature are sensed by sensors that provide supercritical LPG fuel thermodynamic property information and feedback to the fuel and control system 20.

[0042] The supercritical LPG fuel then flows via conduit 104SC to SOV 130. After SOV 130, the pressure and temperature of the supercritical LPG fuel are measured by pressure sensor 132PT.SC and temperature sensor 134TE SC , which provide supercritical LPG fuel thermodynamic property information and feedback to the fuel and control system 20 and PLC 200 via signal path 202, allowing the fuel and control system 20 to manage the flow of supercritical LPG fuel in liquid, gaseous and / or supercritical conditions through the fuel trimming and control system 10. SC and temperature sensor 134TE SC The supercritical LPG fuel is then delivered through the FCV 136 at a fuel demand determined and controlled by the fuel and control system 20. The flow control module 138 may be based on gas turbine core controls 206 information regarding the operating characteristics of the gas turbine 300 and its components.

[0043] By combining the fuel trimming system and control system 10 with the fuel and control system 20 and the gas turbine 300 operational information and fuel demand, the entire fuel trimming system and control system 10 can provide real-time dynamic control and adjustment of liquid LPG fuel to supercritical LPG fuel. Thus, using at least one of the sensed fuel pressure, temperature, and composition characteristics (including their values ​​in the FCV 136 to set a desired FCV 136 position that meets the fuel demand of the gas turbine 300), the FCV 136 can be set to a desired position according to instantaneous, dynamic, and real-time values. The desired position of the FCV 136 can pass an appropriate amount of supercritical LPG to operate the gas turbine 300 under dynamic and steady-state conditions.

[0044] As used herein throughout this specification and claims, approximation language can be applied to modify any quantitative expression that can vary within acceptable limits without resulting in a change in the basic function involved. Thus, values ​​modified by one or more terms such as "approximately," "about," and "substantially" are not limited to the exact value specified. In at least some instances, approximation language can correspond to the precision of the instrument used to measure the value. Here, and throughout this specification and claims, range limitations are combinable and / or interchangeable, and unless the context and language dictate otherwise, such ranges are identified and include all subranges encompassed therein. The term "about," as applied to a particular value in a range, applies to both endpoints and can indicate + / - 10% of the stated value, unless specifically dependent on the precision of the instrument used to measure the value.

[0045] The corresponding structure, material, acts, and equivalents of all means-plus-function or step-plus-function elements in the following claims are intended to encompass any structure, material, or acts for performing that function in combination with other specifically claimed claim elements. The description of the present disclosure has been presented for purposes of illustration and description and is not intended to be exhaustive or to limit the disclosure to the precise form disclosed. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the disclosure. The present embodiments were chosen and described in order to best explain the principles and practical application of the disclosure and to enable others skilled in the art to understand the disclosure in various embodiments with various modifications as suited to the particular uses envisioned. [Explanation of symbols]

[0046] 10 Fuel regulation and control systems 20 Fuel and Control Systems 100 Fuel Supply Subsystem 102 Storage Tank 104 Conduit 104G conduit 104L conduit 104SC conduit 106 Low-pressure pump 108 High-pressure pump 110PT0 pressure sensor 112TE0 temperature sensor 114 Liquid Fuel Metering Valve (LFMV) 115 Variable Frequency Drive (VFD) or Switched Reluctance (SR) Motor (VFD / SR) 116PT L Pressure Sensor 118TE L Temperature Sensor 120 Vaporizer / Heat Exchanger 122PT SC Pressure Sensor 124TE SC Temperature Sensor 126 Mass spectrometer with chromatography function (GC / WIM) 130 Shut-off valve (SOV) 132PT SC Pressure Sensor 134TE SC Temperature Sensor 136 Fuel control valve (FCV) 138 Flow Control Module 140 Heat source 200 Programmable Logic Controller (PLC) 202 Signal Path 206 Gas Turbine Core Control Unit 210 Algorithm 300 Gas turbine, gas turbine engine, gas turbine engine subsystem 302 Gas Manifold 304 Combustor 306 Compressor 308 Power Turbine 309 Shaft 310 Load 311 Shaft 312 Fuel Nozzle / Premixer

Claims

1. A fuel regulation and control system (10) for dynamic control and steady state operation of a gas turbine (300) provided with liquefied petroleum gas (LPG), the fuel regulation and control system (10) comprising: a storage section for LPG fuel; a fuel supply subsystem (100) connecting the reservoir to a gas turbine (300); Fuel and control system (20) It is equipped with the gas turbine (300) including a gas turbine core control (206) that provides at least one operating state of the gas turbine (300) to the fuel and control system (20); the fuel supply subsystem (100) includes at least one sensor for sensing at least one characteristic of the LPG fuel within the fuel supply subsystem (100), the at least one sensor providing data regarding the at least one characteristic of the LPG fuel to the fuel and control system (20); the fuel and control system (20) analyzes data regarding the at least one property of the LPG fuel and at least one operational data of the gas turbine (300) to control the flow of LPG fuel to the gas turbine (300) under dynamic and steady-state conditions; A fuel regulation and control system (10) wherein the fuel supply subsystem (100) includes a vaporizer / heat exchanger (120), the vaporizer / heat exchanger (120) having heat, the heat being applied to the vaporizer / heat exchanger (120) to heat liquid LPG fuel supplied from the fuel supply subsystem (100) to the interior of the vaporizer / heat exchanger (120) and convert the liquid LPG fuel into supercritical LPG fuel.

2. 2. The fuel regulation and control system (10) of claim 1, wherein the at least one sensor for sensing at least one characteristic of the LPG fuel in the fuel supply subsystem (100) comprises at least one pressure sensor (116, 122, 132) and at least one temperature sensor (118, 124, 134).

3. 2. The fuel regulation and control system (10) of claim 1, wherein the at least one sensor for sensing at least one characteristic of the LPG fuel in the fuel supply subsystem (100) comprises a plurality of pressure sensors (116, 122, 132) and a plurality of temperature sensors (118, 124, 134).

4. 10. The fuel trim and control system of claim 1, wherein at least one sensor for sensing at least one characteristic of the LPG fuel in the fuel supply subsystem includes at least one of a gas chromatograph and a calorimeter.

5. 2. The fuel regulation and control system of claim 1, wherein the fuel supply subsystem includes a low pressure pump and a high pressure pump in series, the low pressure pump and the high pressure pump in series increasing the downstream pressure of the LPG fuel within the fuel supply subsystem.

6. 6. The fuel regulation and control system of claim 5, wherein the fuel and control system further includes a programmable logic controller (PLC), the fuel supply subsystem further includes at least one of a variable frequency drive (VFD) and a switched reluctance (SR) motor, the at least one of the VFD and the SR connected to at least the high-pressure pump, and the PLC and the at least one of the VFD and the SR connected such that the PLC can provide operating commands to the at least one of the VFD and the SR to control operation of at least the high-pressure pump.

7. 2. The fuel regulation and control system (10) of claim 1, wherein the fuel and control system (20) further includes a programmable logic controller (PLC) (200), the fuel supply subsystem (100) further includes a liquid fuel metering valve (LFMV) (114), and the PLC (200) and the LFMV (114) are connected such that the PLC (200) can provide operating commands to the LFMV (114) to control the flow of liquid LPG fuel downstream along the fuel supply subsystem (100).

8. the gas turbine (300) includes a gas turbine core control (206), a compressor (306), and a combustor (304), the gas turbine (300) is connected to a load (310), the gas turbine core control (206) senses conditions within the gas turbine (300), and the gas turbine core control (206) provides the gas turbine (300) sensed conditions to the fuel and control system (20); 2. The fuel regulation and control system of claim 1, wherein the sensed conditions include at least one of a compressor discharge pressure, a combustor firing temperature, a combustor pressure, a gas turbine speed, a load demand, a gas turbine temperature, and a gas turbine pressure, and wherein the fuel and control system includes a programmable logic controller (PLC), an algorithm, and a flow control module.

9. 2. The fuel regulation and control system of claim 1, wherein the heat applied to the vaporizer / heat exchanger to heat liquid LPG fuel supplied from the fuel supply subsystem to the interior of the vaporizer / heat exchanger to convert the liquid LPG fuel to supercritical LPG fuel is based on fuel demand of the gas turbine.

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