Method of regulating and controlling supercritical liquefied petroleum gas fuel flow for operation in a gas turbine

Abstract

A fuel regulation and control system (20) is disclosed that provides dynamic control and steady-state operation of a gas turbine (300) fueled by supercritical liquefied petroleum gas (LPG). The fuel regulation and control system (20) includes a storage for LPG fuel; a fuel delivery subsystem (100) that connects the storage to the turbine machinery; and a control system (20). The gas turbine (300) includes a gas turbine core control (206) that provides at least one operating data of the gas turbine (300) to the control system (20). The fuel delivery subsystem (100) includes at least one sensor for sensing at least one property of the LPG fuel in the fuel delivery subsystem (100), wherein the at least one sensor provides data about at least one property of the LPG fuel to the control system (20). The control system (20) analyzes the data about at least one property of the LPG fuel and at least one operating data of the gas turbine (300) for dynamically controlling the LPG fuel to the gas turbine (300) under dynamic and steady-state conditions.

Description

Background Art

[0001] The present disclosure generally relates to fuel conditioning and control systems. More particularly, the present disclosure relates to fuel conditioning systems, fuel control systems, and methods of operating a gas turbine with liquefied petroleum gas (LPG) fuel in a 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 of a gas turbine supplied with liquefied petroleum gas (LPG). The fuel regulation and control system includes a storage for LPG fuel; a fuel delivery subsystem that connects the storage to the gas turbine; and a control system. The gas turbine includes a gas turbine core control that provides at least one operating 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, wherein the at least one sensor provides data about at least one property of the LPG fuel to the control system. The control system analyzes the data about at least one property of the LPG fuel and at least one operating data of the gas turbine for controlling the flow of LPG fuel 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 conditioning and delivery method. The method includes pumping liquid LPG fuel from a storage tank to a gas turbine in a fuel delivery subsystem; converting the liquid LPG fuel from liquid LPG fuel to supercritical LPG fuel; sensing at least one property of the LPG fuel in the fuel delivery subsystem, the sensing providing data about at least one property of the LPG fuel to a control system; and controlling the conversion of the liquid LPG fuel from liquid LPG fuel to supercritical LPG fuel by the control system in response to a fuel flow demand of the gas turbine for dynamic control and steady-state operation of the gas turbine provided with supercritical LPG fuel.

[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 is provided with a storage for LPG fuel; and a fuel delivery subsystem connecting the storage to the gas turbine, wherein the fuel delivery system includes a vaporizer / heat exchanger. The vaporizer / heat exchanger has heat applied thereto to heat liquid LPG fuel delivered thereto from the fuel delivery subsystem to convert the liquid LPG fuel into supercritical LPG fuel, wherein the heat applied thereto is based on a function of the LPG fuel demand of the gas turbine. A control system including a programmable logic controller (PLC) is provided. The fuel delivery subsystem also includes a liquid fuel metering valve (LFMV), the PLC being connected to the LFMV so that the PLC can provide operating instructions to the LFMV to control the flow of LPG fuel along the fuel delivery subsystem. The gas turbine includes a gas turbine core control, which provides at least one operating 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 LPG fuel in the fuel delivery subsystem, and the at least one sensor provides data of at least one property of the LPG fuel to the control system. The control system analyzes the data of at least one property of the LPG fuel and at least one operating data of the gas turbine for dynamically controlling the LPG fuel flow to the gas turbine under dynamic and steady-state conditions. The at least one sensor for sensing at least one property of the LPG fuel in the fuel delivery subsystem includes a plurality of pressure sensors, a plurality of temperature sensors, and LPG fuel property instruments, such as a gas chromatograph and / or a gas calorimeter with chromatographic capabilities, including but not limited to a Wobbe index meter. In addition, the fuel delivery subsystem includes a low-pressure pump and a high-pressure pump connected in series, and the low-pressure pump and the high-pressure pump connected in series increase the pressure of the LPG fuel in the fuel delivery subsystem. The fuel delivery subsystem includes an electric motor speed change device connected to at least the high-pressure pump, such as a variable frequency drive (VFD) or a switched reluctance (SR) motor. The PLC is connected to the VFD / SR so that the PLC can provide operating instructions 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. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0007] Figure 1 shows a schematic diagram of a fuel regulation and control system according to an embodiment of the present disclosure; and

[0008] Figure 2 A schematic diagram illustrating the control mode of a fuel regulation and control system embodied by the present disclosure is shown.

[0009] It should be noted that the drawings of the present disclosure are not drawn to scale. The drawings are intended to depict only typical aspects of the present disclosure and therefore should not be considered to limit the scope of the present disclosure. In the drawings, like numbers represent like elements between the drawings. DETAILED DESCRIPTION

[0010] First, in order to clearly describe the current technology, it will be necessary to select certain terms when referring to and describing relevant machine components within a fuel regulation and control system for a power plant. To the extent possible, common industry terms will be used and adopted in a manner consistent with the accepted meaning of the terms. Unless otherwise stated, such terms should be given a broad interpretation consistent with the context of the present application and the scope of the appended claims. A person of ordinary skill in the art will understand that several different or overlapping terms may be used to refer to a particular component. An object that may be described as a single part in this article may include multiple components and be referenced as consisting of multiple components in another context. Alternatively, an object that may be described as including multiple components in this article may be referred to as a single part elsewhere.

[0011] In addition, several descriptive terms may be used regularly herein, and it should prove helpful to define these terms at the beginning of this section. Unless otherwise indicated, these terms and their definitions are as follows. As used herein, "downstream" and "upstream" are terms that indicate the direction relative to the flow of a fluid, such as fuel to a turbine engine or fuel through one of the component systems of a turbine. The term "downstream" corresponds to the direction of fluid flow, and the term "upstream" refers to the direction opposite to the flow.

[0012] In addition, several descriptive terms may be used regularly herein, as described below. The terms "first," "second," and "third" may be used interchangeably to distinguish one component from another and are not intended to indicate the position or importance of individual components.

[0013] The terms used herein are only used for the purpose of describing specific embodiments and are not intended to limit the present disclosure. As used herein, the singular forms "one", "a kind of" and "the" are intended to also include plural forms, unless the context clearly states otherwise. It will be further understood that when used in the specification, the terms "include" and / or "comprising" specify the presence of stated features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or their groups. "Optional" or "optionally" means that the event or situation described subsequently may or may not occur, and the description includes instances where the event occurs and instances where the event does not occur.

[0014] Where an element or layer is referred to as being "on," "engaged to," "connected to," or "coupled to" another element or layer, it may be directly on, engaged to, connected to, or coupled to another element or layer, or there may be intervening elements or layers. In contrast, when an element is referred to as being "directly on," "directly engaged to," "directly connected to," or "directly coupled to," there may be no intervening elements or layers. Other words used to describe relationships between elements should be interpreted in a similar manner (e.g., "between" versus "directly between," "adjacent" versus "directly adjacent," etc.). As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0015] With reference to the accompanying drawings, Figure 1 A fuel conditioning and control system 10 is shown according to an embodiment of the present disclosure. The fuel conditioning 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 referred to as a "gas turbine").

[0016] In the fuel conditioning and control system 10, liquid LPG is first converted or conditioned to supercritical LPG and may then remain in this phase or be converted or conditioned to gaseous LPG based on the operating conditions and requirements of the fuel conditioning and control system 10. The supercritical LPG is delivered downstream to the gas turbine 300 via the fuel delivery subsystem 100. The LPG fuel flowing downstream through the conditioning and control system 10 is controlled by the fuel and control system 20.

[0017] The fuel delivery 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), 104G (for gaseous fuel) interconnect the elements of the fuel delivery subsystem 100 and connect the storage tank 102 to the gas turbine 300. With respect to the fuel delivery subsystem 100, the LPG flow is from the most upstream component of the fuel delivery subsystem 100 (the storage tank 102) toward the downstream to the end of the fuel delivery subsystem 100 (at the gas turbine 300).

[0018] 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 facilitate drawing liquid LPG from storage tank 102 and moving the liquid LPG fuel through conduit 104L. In addition, low-pressure pump 106 and high-pressure pump 108 increase the total pressure of the liquid LPG fuel from storage tank 102 as the liquid LPG fuel flows downstream along conduit 104L.

[0019] In addition, as liquid LPG fuel is drawn from the storage tank 102, the liquid LPG fuel stream moves downstream, wherein the LPG fuel has various properties measured by at least one fuel property definition instrument, such as, but not limited to, a gas chromatograph or a gas calorimeter (such as a Wobbe index meter) or a mass spectrometer with chromatographic capabilities (GC / WIM) 126. At 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 definition component of the GC / WIM 126 is used to determine the composition components of the liquid LPG fuel, including, but not limited to, qualitative and quantitative hydrocarbon composition aspects, such as, but not limited to, heating value, relative density, vapor pressure, and motor octane number. The calorimeter or Wobbe index component of the GC / WIM 126 measures the interchangeability of the liquid LPG fuel gas, the heating characteristics of the liquid LPG fuel, and the relative ability of the liquid LPG fuel to deliver energy. The measurements from the GC / WIM 126 are fed to the PLC 200 along a signal path 202. Signal path 202 may be any form of signal transmission from GC / WIM 126 (or any data providing device of the disclosed embodiments) Signal path 202 provides data and information / commands to and from elements connected to fuel and control system 20 .

[0020] The fuel delivery subsystem 100 also includes an electric motor speed changing device, such as, but not limited to, a variable frequency drive (VFD) or a 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 is capable of controlling both the low pressure pump 106 and the high pressure pump 108. The VFD / SR 115 controls the operation of at least the high pressure pump 108 in response to a signal from the PLC 200 along the signal path 202, as described herein. The VFD / SR 115 controls the operation of at least the high pressure pump 108 to increase the pressure of the downstream flow of liquid LPG fuel in the conduit 104L after the liquid LPG fuel flows from the high pressure pump 108 to the pressure sensor 110 PT0 and the temperature sensor 112 TE0 (the subscript "0" represents the "original" liquid LPG fuel from the storage tank 102).

[0021] The fuel delivery subsystem 100 also includes liquid LPG fuel flowing downstream from the pump 106 and the high pressure pump 108 in the conduit 104L, which extends through a series of sensors (pressure sensor 110 PT0 and temperature sensor 112 TE0). The pressure sensor 110 PT0 and the temperature sensor 112 TE0 measure the liquid LPG fuel after it flows through the pumps 106, 108. Each of the pressure sensor 110 PT0 and the temperature sensor 112 TE0 provides liquid LPG property information and feedback to the fuel and control system 20 and the PLC 200 along a signal path 202 (for ease of description, illustration and understanding, not all paths 202 are shown). Thus, the flow of liquid LPG fuel through the fuel conditioning system and control system 10 is managed and controlled. Both the pressure sensor 110 PT0 and the temperature sensor 112 TE0 include an embedded transmitter enabling component that enables the liquid LPG property information and feedback to be sent to the fuel and control system 20 and the PLC 200 along the signal path 202.

[0022] Fuel conduit 104L directs the flow of liquid LPG from low pressure pump 106 and high pressure pump 108 downstream to a liquid fuel metering value (LFMV) 114. LFMV 114 is controlled by programmable logic controller (PLC) 200 to allow liquid LPG fuel to flow therethrough in an amount that enables the liquid LPG fuel to be converted into supercritical LPG fuel in vaporizer / heat exchanger 120, as described herein. LFMV 114 meters the flow of liquid LPG fuel downstream and is capable of stably controlling the flow rate. LFMV 114 may include any configuration of metering valves now known or hereinafter described that is capable of metering the flow of liquid LPG fuel and stably controlling the flow rate of liquid LPG fuel downstream along conduit 104L.

[0023] From LFMV 114, in fuel delivery subsystem 100, liquid LPG fuel flows downstream along conduit 104L and passes through pressure sensor 116 PT L and temperature sensor 118 TE L , where "L" represents "liquid" of liquid LPG fuel. Like the pressure sensor 110 PT0 and the temperature sensor 112 TE0, the pressure sensor 116 PT L and temperature sensor 118 TE L Liquid LPG property information and feedback is provided to the fuel and control system 20 and PLC 200 along signal path 202. Thus, the flow of liquid LPG fuel downstream through the fuel conditioning and control system 10 and fuel delivery subsystem 100 is managed and controlled. Pressure sensor 116 PT L and temperature sensor 118 TE L Both include embedded transmitter enabling components that enable liquid LPG fuel property information and feedback along signal path 202 to the fuel and control system 20 and PLC 200 .

[0024] Conduit 104L leads downstream to a reactor or vaporizer / heat exchanger 120 in the fuel delivery subsystem 100. According to embodiments of the present disclosure, the vaporizer / heat exchanger 120 of the fuel delivery subsystem 100 may include a known or hereinafter presented vaporizer / heat exchanger 120 configuration. The known or hereinafter presented vaporizer / heat exchanger 120 configuration according to the embodiments includes at least a rigid non-expanding wall that is tight enough to withstand the high pressures therein. According to aspects of the embodiments, the vaporizer / heat exchanger 120 configuration in the fuel delivery subsystem 100 enables heat to be applied to the contents of the vaporizer / heat exchanger 120. The heat can be applied inside the vaporizer / heat exchanger 120 or applied outside the vaporizer / heat exchanger 120 and transferred through the wall via normal thermodynamics. The source 140 of applied heat may be obtained from, but not limited to, a power source such as, but not limited to, an electrical resistor or a heat tracing circuit; the heat source 140 may obtain energy from an externally induced high temperature fluid flow such as, but not limited to, oil or water vapor (steam).

[0025] In the vaporizer / heat exchanger 120, heat is applied to the liquid LPG fuel in the non-expansion range of the vaporizer / heat exchanger 120 wall. When there is no expansion at high temperature, under basic thermodynamic principles, the liquid LPG fuel is placed under specific conditions of pressure and temperature, where the critical point of the liquid LPG fuel is obtained. When the liquid LPG fuel is subjected to pressures and temperatures above its critical point, the liquid LPG fuel is "supercritical". When the LPG fuel is heated above its critical temperature and compressed at a pressure above its critical pressure, the LPG fuel is "supercritical". In the supercritical region, the LPG fuel is now a supercritical LPG fuel, which exhibits specific supercritical properties and has an intermediate behavior between a liquid and a gas. Specifically, a supercritical fluid (SCF) has properties such as liquid-like density, gas-like viscosity, and diffusion values ​​between liquids and gases.

[0026] In addition, the vaporizer / heat exchanger 120 of the fuel delivery subsystem 100 is connected to the fuel and control system 20 and the PLC 200 along the signal path 202 to receive and send information. The vaporizer / heat exchanger 120 sends information such as the temperature and pressure of the vaporizer / heat exchanger 120 to the fuel and control system 20 and the PLC 200 along the signal path 202 to help control the vaporizer / heat exchanger 120 and the entire regulation system and control system 10 in the fuel and control system 20 and the PLC 200. Specifically, the vaporizer / heat exchanger 120 provides information to the fuel and control system 20 and the PLC 200 to provide control and operating parameters to at least one of the VFD 115 and the LFMV 114. In addition, the vaporizer / heat exchanger provides information to the PLC 200 to control the heat applied to the liquid LPG to convert it into supercritical LPG by adjusting the heat demand entering from the heat source 140 according to its operating principle. This could be, but is not limited to, regulating the flow of an incoming high temperature fluid such as, but not limited to, steam or oil, by regulating the electrical current through electrical resistance or heat tracing.

[0027] The now supercritical LPG fuel leaves conduit 104SC from vaporizer / heat exchanger 120 in fuel delivery subsystem 100. The supercritical LPG fuel then flows downstream to another set of sensors, namely pressure sensor 122 PT SC and temperature sensor 124 TE SC (where "SC" stands for supercritical). As with the above sensor group, the pressure sensor 122 PT SC and temperature sensor 124 TE SCLPG fuel property information and feedback is provided to the fuel and control system 20 and PLC 200 along signal path 202. However, at this location in the fuel conditioning system and control system 10 after the vaporizer / heat exchanger 120, the pressure sensor 122 PT SC and temperature sensor 124 TE SC Supercritical LPG fuel property information and feedback is provided to the fuel and control system 20 and the PLC 200 along signal path 202. Thus, the flow of liquid LPG fuel through the fuel conditioning and control system 10 (including the fuel delivery subsystem 100) is controlled by the pressure sensor 122 PT SC and temperature sensor 124 TE SC To manage and control, the pressure sensor and temperature sensor also include an embedded transmitter enabling component that enables supercritical LPG fuel property information and feedback to reach the fuel and control system 20 and PLC 200 along signal path 202 to control the fuel conditioning system and control system 10 and fuel delivery subsystem 100 as described herein.

[0028] The supercritical LPG fuel flows downstream through the conduit 104SC of the fuel delivery subsystem 100, wherein at least one shutoff value (SOV) 130 is positioned in the fuel and control system 20. The SOV 130 allows the flow of the supercritical LPG fuel to be stopped after the supercritical LPG fuel is produced. In one aspect of the embodiment, the SOV 130 allows the flow of the supercritical LPG fuel to be stopped manually by actuating the SOV 130. Alternatively, the SOV 130 allows the flow of the supercritical LPG fuel to be stopped via a signal from the fuel and control system 20 when any condition in the regulation system and control system 10 is sensed as abnormal by any one of the following series of sensors: pressure sensor 110 PT0 and temperature sensor 112 TE0, pressure sensor 116 PT0 L and temperature sensor 118 TE L ; Pressure sensor 122 PT SC and temperature sensor 124 TE SC ; and / or pressure sensor 132PT SC and temperature sensor 134 TE SC(to be described below). In addition, in addition or alternatively, the SOV 130 allows the flow of supercritical LPG fuel in the fuel and control system 20 to be stopped via a signal from the fuel and control system 20. According to certain aspects of the embodiment, the stop of the LPG fuel may be due to any abnormal condition sensed by an element of the PLC 200 connected to the fuel and control system 20 (including but not limited to the GC / WIM 126, VFD / SR 115, LFMV 114, vaporizer / heat exchanger 120 and / or heat source 140) at any fuel delivery subsystem 100 location. In addition, the SOV 130 allows the flow of supercritical LPG fuel in the fuel and control system 20 to be stopped by a signal from the control system 20 because of an abnormal condition sensed by the gas turbine (GT) subsystem 300 via the GT core control 206 (to be described below) under any condition. In addition, if necessary and justified for operational or safety-related conditions, multiple SOV 130 components may be present in the fuel and control system 20.

[0029] As the supercritical LPG fuel flows downstream through the SOV 130 in the fuel and control system 20, the supercritical LPG fuel then flows through another series of sensors, namely, pressure sensor 132 PT SC and temperature sensor 134 TE SC (where “SC” stands for supercritical). As with other sensors according to aspects of the present disclosure, the pressure sensor 132 PT SC and temperature sensor 134TE SC Each of the pressure sensors 132 PT is connected to the fuel and control system 20 via a signal line 202. SC and temperature sensor 134 TE SC Each provides LPG fuel property information and feedback to the fuel and control system 20 and the PLC 200 along signal path 202 and enables the fuel and control system 20 to appropriately define and manage the flow of the LPG fuel in its liquid, gaseous and / or supercritical state through the fuel conditioning system and control system 10 as described herein.

[0030] The supercritical LPG fuel passes through a series of sensors (pressure sensor 132 PT SC and temperature sensor 134TE SC), the supercritical LPG fuel in conduit 104SC flows downstream to a fuel control valve (FCV) 136 of the fuel and control system 20. The FCV 136 allows the supercritical LPG fuel to flow at an appropriate rate, as determined by the fuel and control system 20 when provided with inputs from the fuel conditioning system and control system 10 components, as described herein. At the FCV 136 of the fuel delivery subsystem 100, the FCV 136 allows the fuel to pass therethrough according to the fuel demand required for the gas turbine 300 to operate under the sensed operating conditions. The fuel demand required for the gas turbine 300 to operate under the sensed operating conditions is provided by the gas turbine core control 206.

[0031] Further details of the gas turbine core control 206 and the conditions sensed by the gas turbine core control 206 are described below. For ease of understanding, the gas turbine core control 206 senses conditions in the gas turbine 300, including, but not limited to, compressor 306 discharge pressure, compressor 306 speed, combustor 304 firing conditions, low pressure turbine pressure, combustor 304 pressure, gas turbine speed, load 310 demand, power turbine 308 temperature and pressure, and other such gas turbine 300 operating variables now known or determined below. The sensed conditions provided by the characteristics of the gas turbine 300 sensed by the gas turbine core control 206 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 provided by the characteristics of the gas turbine 300 sensed by the gas turbine core control 206 are analyzed and evaluated by the algorithm 210 (together with the PT 132 respectively). SC and TE 134 SC 106, and the LPG fuel composition measured and defined by the GC / WIM 126). Feedback may be provided to the components of the fuel delivery subsystem 100 for enhanced and dynamic operation, including dynamic operation based on real-time data. As used herein, dynamic operation includes operational modifications required by the fuel and control system 20 to analyze and evaluate real-time data. In certain aspects of the described embodiments, the components of the fuel delivery subsystem 100 to which feedback may be provided for enhanced and 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.

[0032] At the FCV 136 of the fuel and control system 20, the supercritical LPG fuel flow is throttled to meet the LPG fuel demand downstream of the GT 300 in the conduit 104G / 104SC (where "G" means gaseous and "SC" means supercritical); the fuel may be in the gas phase or the supercritical phase depending on the operating conditions of the GT 300. The gas / supercritical LPG fuel is fed from the conduit 104 / 104G / 104SC to the gas manifold 302 of the gas turbine 300. At the gas manifold 302, the gas / supercritical LPG fuel is distributed among all the fuel nozzles / premixers 312. In some cases, the gas / supercritical LPG fuel is combined with the compressed fluid (typically air) from the compressor 306 inside the fuel nozzles / premixers before entering the combustor 304. In some cases, the gas / supercritical LPG fuel is combined with the compressed fluid (typically air) from the compressor 306 at the combustor 304. The gas / supercritical LPG fuel and compressed air are then ignited in the combustor 304. The gas / supercritical LPG fuel ignited and expanded at this time is directed from the combustor 304 to the (gas) power turbine 308, wherein the rotational motion of the gas power turbine 308 is transmitted to the rotor or shaft 309 / 311. The rotor or shaft 309 is mechanically connected to the compressor 306 from the gas power turbine 308 to rotate the compressor 306. In some cases, the rotor or shaft 309 may be independent of the rotor or shaft 309 / 311 to connect to the load 310, which is driven by the rotation of the rotor or shaft 309 / 311. In addition, 309 / 311 may represent multiple shafts, all of which can 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 appearing below.

[0033] Reference Figure 1 and Figure 2 , the fuel and control system 20 and its interaction with the components of the fuel regulation and control system 10 and the fuel delivery subsystem 100 will now be described. As described, the fuel and control system 20 includes a PLC 200. The PLC 200 is connected to a number of elements of the fuel regulation and control system 10, including, but not limited to: a series of sensors, namely, a pressure sensor 110 PT0 and a temperature sensor 112 TE0, a pressure sensor 116 PT L and temperature sensor 118 TE L ; Pressure sensor 122 PT SC and temperature sensor 124 TE SC ; and / or pressure sensor 132 PT SC and temperature sensor 134 TE SC; GC / WIM 126; VFD / SR 115 and low pressure pump 106 and high pressure pump 108 through VFD / SR 115; LFMV 114; vaporizer / heat exchanger 120; heat source 140; SOV 130, FCV 136 and gas turbine 300 through gas turbine core control 206. As described above, signal path 202 interconnects the above elements with components of fuel and control system 20 and fuel conditioning system and control system 10.

[0034] The fuel and control system 20 includes a PLC 200. The PLC 200 is a programmable logic controller that is configured for use control of the fuel conditioning system and control system 10. In one aspect of the embodiment, the PLC 200 may include a small modular device with limited inputs and outputs (I / O). In other aspects of the embodiment, the PLC 200 may include large devices, and in other aspects, the PLC 200 may be networked to other PLCs and other systems of the power plant incorporating the fuel conditioning system and control system 10. The PLC 200 provides a flexible, rugged and direct controller with highly reliable automation in the harsh environment of a power plant. In various aspects of the embodiment, the PLC 200 may be any currently known PLC or a PLC that appears below.

[0035] The fuel and control system 20 includes a flow control module 138. The flow control module 138 is connected to the FCV 136 and receives data from the algorithm 210, as described herein. The flow control module 138 is connected to the FCV 136 to control the positioning of the FCV 136 so that the supercritical LPG fuel flows downstream in the fuel conditioning system and control system 10 at an appropriate rate as specified by the fuel and control system 20 when provided with input from the fuel conditioning system and control system 10. Specifically, the FCV 136 allows fuel to pass therethrough when the fuel demand determined by the gas turbine core control 206 determines the fuel demand required for the gas turbine 300 to operate under the sensed conditions.

[0036] The flow control module 138 receives inputs from various components of the fuel delivery subsystem 100 in the fuel regulation and control system 10. The flow control module 138 is connected to the algorithm 210 which is a component of the fuel and control system 20. Figure 2 As shown, the algorithm 210 receives information about the fuel composition x from the PLC 200. i Data signal and data, where the fuel composition x i The data originates from the GC / WIM 126. In addition, the algorithm 210 receives signals and data of pressure p and temperature T from a series of sensors: pressure sensor 110 PT0 and temperature sensor 112 TE0, pressure sensor 116 PTL and temperature sensor 118 TE L ; Pressure sensor 122 PT SC and temperature sensor 124 TE SC ; and / or pressure sensor 132 PT SC and temperature sensor 134 TE SC The pressure p and temperature T signals and data from the series of sensors can be used by the algorithm 210 for system control purposes as required.

[0037] The algorithm 210 provides an output of an estimated value of the specific gravity SG, the specific heat ratio k, and the lower heating value LHV. The specific gravity SG and the specific heat ratio k are provided to the flow control module 138. The flow control module 138 is also provided with a PT 132 SC The pressure p1 is given, or for the purposes of this disclosure, may be given separately by any additional pressure sensor dedicated to feeding this value to the flow control 138. This pressure p1 represents the inlet pressure of the FCV 136; and together 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 define the position of the valve. Therefore, the flow control module 138 of the fuel and control system 20 in conjunction with the PLC 200 of the fuel regulation system and control system 10 can determine that the LFMV 114 of the fuel delivery subsystem 100 is positioned for the required fuel demand of the gas turbine 300, wherein the required fuel demand of the gas turbine 300 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 system 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 system and control system 10 may determine the FCV 136 positioning for the required fuel demand for the gas turbine 300 based on the supercritical conditions encountered at the FCV 136, wherein the required fuel demand for 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.

[0038] Furthermore, according to other aspects of the embodiment, the fuel and control system 20 having the flow control module 138 in combination with the PLC 200 and the algorithm 210 may determine a preferred temperature or amount of heat "Q" to be applied from the heat source 140 to the vaporizer / heat exchanger 120. Applying the determined preferred temperature or amount of heat "Q" from the heat source 140 to the vaporizer / heat exchanger 120 may enable the vaporizer / heat exchanger 120 to operate at a high efficiency level to convert liquid LPG fuel to supercritical LPG fuel at a desired temperature. The preferred temperature or amount of heat "Q" applied from the heat source 140 to the vaporizer / heat exchanger 120 may be determined as a function "f" of process variables such as, but not limited to, temperature, pressure, and LPG flow demand. In other words, Q=F(LPG demand). Furthermore, the temperature or amount of heat "Q" applied to the vaporizer / heat exchanger 120 may be determined as a function of one or more standard fuel property characteristics including, but not limited to, specific volume v, specific heat c p , absolute viscosity η, thermal conductivity λ and specific enthalpy h, critical temperature T c and / or critical pressure p c . In addition, the temperature or heat "Q" can be determined based on the operating principle of the heat source 140 as a function of one or more operability variables, which include but are not limited to the resistance of the electric heater, or the heat conduction and convection parameters of the incoming high temperature fluid such as steam or oil.

[0039] In addition, the fuel and control 20 can use the data to determine the desired real-time operating conditions of the fuel delivery subsystem 100 and its components. Using real-time data defining the real-time operating conditions of the entire fuel conditioning and control system 10 and the fuel delivery subsystem 100, the FCV 136 can be set to a desired position based on instantaneous and real-time values ​​using sensed fuel pressure, temperature, and composition (including those values ​​at the FCV 136 inlet for setting the desired FCV 136 position). The desired position of the FCV 136 allows the supercritical LPG to pass therethrough in appropriate amounts to operate the gas turbine 300 under dynamic and steady-state conditions.

[0040] Thus, embodiments of the present disclosure provide a fuel conditioning system and control system 10, a fuel and control system 20, and a related method for operating a gas turbine with LPG fuel in a supercritical phase. The embodiment includes a fuel and control system 20 and an associated algorithm 210 enabling software with supercritical LPG properties that provides dynamic gas turbine fuel control for the embodiment. In addition, as described herein, managing flows in the fuel conditioning system and control system 10 can result in enhanced durability of the fuel conditioning system and control system 10 and the fuel delivery subsystem 100 components that handle supercritical LPG fuel. In addition, instruments such as gas chromatographs and calorimeters (such as Wobbe index meters WIM) that can assess thermodynamic fuel properties and LPG composition also enable the fuel conditioning system and control system 10 and the fuel delivery subsystem 100 to automatically dynamically adjust fuel flows in real time during operation of the gas turbine 300.

[0041] As embodied in the present disclosure, the fuel conditioning system and control system 10 provide robustness to gas turbine operation by adding real-time data, including but not limited to accurate values ​​of LPG density, specific heat ratio, superheat requirement, and mass diffusion range in liquid, gas, and supercritical phases. This real-time data can avoid trips caused by fuel property differences and corresponding operational fluctuations. In addition, the fuel conditioning system and control system 10 can provide a variety of LPG fuel compositions for gas turbine 300 operation, including but not limited to LPG fuels containing at least one of methane, ethane, hexane, pentane, propane, and butane.

[0042] In an embodiment, the fuel conditioning system and control system 10 delivers liquid LPG fuel from a storage or storage tank 102 toward the downstream to the gas turbine 300, while converting the liquid LPG fuel from a liquid state to a supercritical state. The LPG fuel flows in the fuel delivery subsystem 100 and the flow is controlled by the fuel and control system 20. The liquid LPG fuel flow in the conduit 104L comes from the storage tank 102, with a low-pressure pump 106 and a high-pressure pump 108 that provide power to the liquid LPG fuel. As described above, the VFD / SR115 drives the high-pressure pump 108. The VFD / SR 115 drives the high-pressure pump 108 by a signal from the fuel and control system 20. The GC / WIM126 obtains composition information of the liquid LPG fuel, including the interchangeability of the liquid LPG fuel gas, the liquid LPG fuel heating characteristics, and the relative ability of the liquid LPG fuel to deliver energy before the liquid LPG fuel moves through the low-pressure pump 106 and the high-pressure pump 108. After low pressure pump 106 and high pressure pump 108, the liquid LPG fuel flows downstream to a first set of sensors, namely pressure sensor 110 PT0 and temperature sensor 112 TE0. The flow of the liquid LPG fuel is then metered and controlled by LFMV 114, which allows flow downstream as determined by the fuel and control system 20. After LFMV 114, the pressure and temperature of the liquid LPG fuel are measured by another set of sensors, namely pressure sensor 116 PT L and temperature sensor 118 TE L The liquid LPG fuel then enters the reactor or vaporizer / heat exchanger 120. In the vaporizer / heat exchanger 120, heat is applied to the vaporizer / heat exchanger 120 by the heat source 140 to heat the liquid LPG fuel to supercritical LPG fuel. The supercritical LPG fuel then flows toward the downstream and again has its pressure and temperature sensed by the pressure sensor 122 PT SC and temperature sensor 124TE SC Sensing, the sensor provides supercritical LPG fuel thermodynamic property information and feedback to the fuel and control system 20.

[0043] The supercritical LPG fuel then flows in conduit 104SC to SOV 130. After SOV 130, the pressure and temperature of the supercritical LPG fuel are again measured by pressure sensor 132 PT SC and temperature sensor 134 TE SC Senses and provides supercritical LPG fuel thermodynamic property information and feedback along signal path 202 to the fuel and control system 20 and PLC 200, and enables the fuel and control system 20 to manage the flow of supercritical LPG fuel in its liquid, gaseous and / or supercritical state through the fuel conditioning system and control system 10. At pressure sensor 132 PTSC and temperature sensor 134 TE SC Thereafter, the supercritical LPG fuel is subsequently fed 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 operating characteristics of the gas turbine 300 and its components.

[0044] The fuel conditioning system and control system 10, in conjunction with the fuel and control system 20 and the operational information and fuel requirements of the gas turbine 300, enables the entire fuel conditioning system and control system 10 to provide real-time and dynamic control and regulation of liquid LPG fuel to supercritical LPG fuel. Thus, the FCV 136 may be set at a desired position using at least one of the sensed fuel pressure, temperature, and composition characteristics based on instantaneous, dynamic, and real-time values, including those values ​​at the FCV 136 for setting a desired FCV 136 position that meets the fuel requirements of the gas turbine 300. The desired position of the FCV 136 allows the supercritical LPG to pass therethrough in an appropriate amount to operate the gas turbine 300 under dynamic and steady-state conditions.

[0045] As used throughout the specification and claims, approximate language can be used to modify any quantitative representation that can be allowed to vary without causing a change in the basic function associated with it. Therefore, the values ​​modified by one or more terms (such as "about", "approximately" and "substantially") are not limited to the specified precise values. In at least some cases, approximate language can correspond to the precision of the instrument used to measure the value. Here and throughout the specification and claims, range limitations can be combined and / or interchangeable. Unless the context or language indicates otherwise, these ranges are identified and include all subranges contained therein. "Approximately" applied to a specific value of a range applies to both end values, and + / -10% of the value can be indicated unless otherwise dependent on the precision of the instrument for measuring the value.

[0046] The corresponding structures, materials, actions and equivalents of all means or steps plus function elements in the following claims are intended to include any structure, material or action for performing functions in conjunction with other claimed elements specifically claimed. A description of the present disclosure has been given for the purpose of illustration and description, but it is not intended to be exhaustive or to limit the present disclosure to the disclosed form. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and essence of the present disclosure. Embodiments have been selected and described in order to best explain the principles and practical applications of the present disclosure, and to enable other persons of ordinary skill in the art to understand the various embodiments of the present disclosure with various modifications suitable for the intended specific use.

Claims

1. A fuel regulation and control system (20) for dynamic control and steady-state operation of a gas turbine (300) supplied with liquefied petroleum gas (LPG), the fuel regulation and control system (20) comprising: Storage tank for LPG fuel; a fuel delivery subsystem (100) connecting the reservoir to a gas turbine (300); Fuel and control systems (20); a heat source, the heat source comprising at least one of electrical properties or heat exchange properties, configured to heat the liquid LPG fuel delivered from the fuel delivery subsystem (100) and convert the liquid LPG fuel into supercritical LPG fuel; The gas turbine (300) includes a gas turbine core control (206) that provides at least one operating condition of the gas turbine (300) to the fuel and control system (20); and The fuel delivery subsystem (100) includes at least one sensor for sensing at least one property of the LPG fuel in the fuel delivery subsystem (100), the at least one sensor providing data about the at least one property of the LPG fuel to the fuel and control system (20); wherein the fuel and control system (20) analyzes the 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.

2. The fuel regulation and control system (20) of claim 1, wherein the at least one sensor for sensing at least one property of the LPG fuel in the fuel delivery subsystem (100) comprises at least one pressure sensor (116, 122, 132) and at least one temperature sensor (118, 124, 134).

3. The fuel regulation and control system (20) of claim 1, wherein the at least one sensor for sensing at least one property of the LPG fuel in the fuel delivery subsystem (100) comprises a plurality of pressure sensors (116, 122, 132) and a plurality of temperature sensors (118, 124, 134).

4. The fuel conditioning and control system (20) of claim 1, wherein the at least one sensor for sensing at least one property of the LPG fuel in the fuel delivery subsystem (100) comprises at least one of a gas chromatograph and a calorimeter.

5. The fuel regulation and control system (20) of claim 1, wherein the fuel delivery subsystem (100) comprises a low-pressure pump (106) and a high-pressure pump (108) connected in series, the low-pressure pump (106) and the high-pressure pump (108) connected in series increasing the downstream pressure of the LPG fuel in the fuel delivery subsystem (100).

6. The fuel regulation and control system (20) according to claim 5, wherein the fuel and control system (20) further comprises a programmable logic controller (PLC) (200), the fuel delivery subsystem (100) further comprises at least one of a variable frequency drive (VFD) (115) and a switched reluctance (SR) motor, wherein at least one of the VFD (115) and the SR motor is connected to at least the high-pressure pump (108), and the PLC (200) is connected to at least one of the VFD (115) and the SR motor so that the PLC (200) can provide operating instructions to at least one of the VFD (115) and the SR motor for controlling the operation of at least the high-pressure pump (108).

7. The fuel regulation and control system (20) according to claim 1, wherein the fuel and control system (20) further comprises a programmable logic controller (PLC) (200), and the fuel delivery subsystem (100) further comprises a liquid fuel metering valve (LFMV) (114), wherein the PLC (200) is connected to the LFMV (114) so ​​that the PLC (200) can provide operating instructions to the LFMV (114) to control the flow of liquid LPG fuel toward the downstream along the fuel delivery subsystem (100).

8. The fuel regulation and control system (20) of claim 1, wherein the gas turbine (300) comprises a gas turbine core control (206), a compressor (306), a combustor (304); the gas turbine (300) is connected to a load (310); wherein the gas turbine core control (206) senses a condition in the gas turbine (300), and the gas turbine core control (206) provides the sensed gas turbine (300) condition to the fuel and control system (20); The sensed conditions include at least one of a compressor (306) discharge pressure, a combustor (304) firing temperature, a combustor (304) pressure, a gas turbine (300) speed, a load (310) demand, a gas turbine (300) temperature, and a gas turbine (300) pressure, and further, the fuel and control system (20) includes a programmable logic controller (PLC) (200), an algorithm (210), and a flow control element, the flow control element being used to evaluate data regarding at least one property of the LPG fuel and at least one operating data of the gas turbine (300) to dynamically control the LPG fuel to the gas turbine (300) under dynamic and steady-state conditions.

9. The fuel conditioning and control system (20) of claim 1, wherein the heat source is a vaporizer / heat exchanger (120) of the fuel delivery subsystem (100), the vaporizer / heat exchanger (120) having heat applied thereto to heat the liquid LPG fuel delivered thereto from the fuel delivery subsystem (100), thereby converting the liquid LPG fuel into the supercritical LPG fuel.

10. The fuel conditioning and control system (20) of claim 9, wherein the heat applied thereto to heat the liquid LPG fuel delivered thereto from the fuel delivery subsystem (100) to heat the liquid LPG fuel to the supercritical LPG fuel is based on the fuel demand of the gas turbine (300).

11. A method for regulating and delivering liquefied petroleum gas (LPG) fuel, the method comprising: pumping liquid LPG fuel from a storage tank (102) to a gas turbine (300) in a fuel delivery subsystem (100); converting the liquid LPG fuel from liquid LPG fuel to supercritical LPG fuel via a heat source (140), the heat source comprising at least one of an electrical property or a heat exchange property; sensing at least one property of the LPG fuel in the fuel delivery subsystem (100), the sensing providing data regarding the at least one property of the LPG fuel to a fuel and control system (20); The conversion of the liquid LPG fuel from liquid LPG fuel to supercritical LPG fuel is controlled by the fuel and control system (20) in response to a fuel demand of the gas turbine (300) for dynamic and steady-state operation of the gas turbine (300).

12. The LPG fuel conditioning and delivery method of claim 11, wherein pumping comprises pumping the liquid LPG fuel from a storage tank (102) to a gas turbine (300) in a fuel delivery subsystem (100) having a low pressure pump (106) and a high pressure pump (108).

13. The LPG fuel conditioning and delivery method of claim 12, further comprising driving at least one of the low pressure pump (106) and the high pressure pump (108) by at least one of a variable frequency drive (VFD) (115) or a switched reluctance (SR) motor.

14. The LPG fuel conditioning and delivery method of claim 11, wherein sensing comprises sensing at least one property of the liquid LPG fuel in the fuel delivery subsystem (100) by at least one sensor, the at least one sensor for sensing at least one property comprising at least one pressure sensor (116, 122, 132) and at least one temperature sensor (118, 124, 134).

15. The LPG fuel conditioning and delivery method of claim 14, wherein sensing comprises sensing pressure and temperature at the at least one pressure sensor (116, 122, 132) and the at least one temperature sensor (118, 124, 134), each of the at least one pressure sensor (116, 122, 132) and the at least one temperature sensor (118, 124, 134) being disposed along the fuel delivery subsystem (100).

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