DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Objections
Claim 20 is objected to because of the following informalities: change claim 20 accordingly (for proper antecedent basis): “based on [[a]] the monitored pressure being”.
Appropriate correction is required.
Claim Rejections - 35 USC § 102/103
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claim(s) 1-4, 9 and 13-15 is/are rejected under 35 U.S.C. 102(a)(1) as anticipated by Pub. No.: US 2012/0285175 A1 (Fletcher) or, in the alternative, under 35 U.S.C. 103 as obvious over Fletcher in view of US Patent 2,911,789 (Baker) and Pub. No. US 2021/0095599 A1 (Asai).
Regarding claim 1, Fletcher discloses (see fig. 2) a turbine engine 10 comprising: a combustor 30 positioned in a core air flow path (the core engine is 20b,30,40a and the combustor 30 received air flow from the high pressure compressor 20b and delivers combustion gasses to high pressure turbine 40a; the air flow and combustion gasses comprising the core flow path) that combusts a compressed air flow (from HPC 20b) and a primary fuel flow (from fuel duct 110) to generate combustion gases (fuel and air are combusted in the primary and secondary combustion zones, see par. 35, to create combustion gasses that are expanded in the turbine section 40 to create exhaust gases, see par. 32); and a fuel (fuel is injected into the primary combustion zone from duct 110 and the secondary combustion zone from duct 112; see par. 35, top) and steam (steam is injected into the primary combustion zone from duct 70 and the secondary combustion zone from duct 72; see pars. 32, bottom and 33, top) system fluidly coupled to the combustor 30, the fuel and steam system comprising: a steam system 60,70,72 to provide a steam flow (see par. 33) along a steam supply line (see annotated figure below) to the combustor 30; and a fuel system to provide the primary fuel flow (flow at duct 110 that is provided to the primary combustion zone, see par. 35) and a secondary fuel flow (flow at duct 112 that is provided to the secondary combustion zone, see par. 35) to the combustor 30, the fuel system having a first state in which there is a first flow rate (valve 112’ selectively controls the second fuel flow in duct 112 and thus there is a first flow rate and a second flow rate; see par. 35) of the secondary fuel flow (in duct 112) to the combustor 30 and a second state in which there is a second flow rate (valve 112’ selectively controls the second fuel flow in duct 112 and thus there is a first flow rate and a second flow rate; see par. 35) of the secondary fuel flow (in duct 112) of the secondary fuel flow (in duct 112) to the combustor 30, the first flow rate and the second flow rate being different (valve 112’ selectively controls the second fuel flow in duct 112 and thus the two instant flow rates can be different; see par. 35). The phrase “the first state and the second state based on a condition of the steam system” is intended use and Fletcher is capable of performing the intended use. For example a start-up is difficult with steam injection gas turbine because the steam is not a sufficient pressure state because the low temperature exhaust gasses 50 during start-up cannot heat the steam sufficiently in the boiler 60 during start-up (see par. 8). The Fletcher water injection can improve start-up times (see pars. 12-13). However, if the water injection was inoperable (or maximum efficiency was desired; see par. 40, middle), then a rapid start-up from idle to full power would not be possible and thus fuel flow required for full power would be limited because the steam availability was limited due to the low temperature exhaust gas from the gas turbine. Thus if the steam was at a low pressure, then the plant operator would place limits on the fuel flow for example during start-up. For the above reasons, it is thought Fletcher is capable of performing the instant intended use. However, in a scenario Fletcher may not be capable of performing the intended use, it can be said that Fletcher does not explicitly disclose “the first state and the second state based on a condition of the steam system”.
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Baker and Asai together teach a first state (i.e., a first flow rate of a fuel) and a second state (i.e., a second flow rate of a fuel) based on a condition of a steam system. The steam pressure of a steam system could be monitored by a plant operator as taught by Baker (see Baker col. 4, ll. 30-35 providing an example of the plant operator monitoring a steam pressure of a heat system 1g and taking an action at the time of a threshold of sufficient steam pressure; and thus this teaching applied to Fletcher would result in a plant operator of Fletcher monitoring a steam pressure of heat recovery system 60 and taking action at a steam pressure threshold). Asai teaches (see fig. 1) that a gas turbine plant (see par. 13) operator may manually adjust (see pars. 45, middle, and 53, bottom) a fuel flow rate (via shutoff and; or control valves 62,63,64,65) to the gas turbine engine combustor 3 (see par. 45 discussing the general concept of manual operation and par. 53 discussing manual control of fuel flow control devices 62-65).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Fletcher with the first state and the second state based on a condition of the steam system as taught by Baker and Asai in order to facilitate improved regulation (see Baker col. 1, ll. 18-23) of the power plant (as discussed in Fletcher par. 2, top) with flexibility of control (see Asai par. 45) to accommodate maintenance and other operations for example.
Regarding claim 2, Fletcher discloses (see fig. 2) the steam flow (from duct 72) and the secondary fuel flow (from duct 112) are provided at the same axial location (the steam flow and the secondary fuel flow can be from the same injector; see par. 33, middle and bottom) along a length of the combustor 30.
Regarding claim 3, Fletcher discloses (see fig. 2) the secondary fuel flow (in line 112 at axial location of line 112) is provided upstream of the steam flow steam flow (at line 72 that is from boiler 60; wherein the steam flow is in a steam injector, see par. 33, bottom; the instant fuel injection is upstream from the steam injection with respect to the annotated direction of the fuel flow in annotated figure above, this is consistent with applicant par. 18 because the claim does not specify which fluid the term “upstream” is with respect to; it is noted for clarity that duct 106 is for water injection rather than for steam injection).
Regarding claim 4, Fletcher discloses the secondary fuel flow (at duct 112) is provided downstream (with respect to the flow of working fluid in the engine 10 for example with respect to the direction of the core flow discussed in the claim 1 analysis above) of the primary fuel flow (at duct 110).
Regarding claim 9, Fletcher discloses (see fig. 2) a secondary fuel supply line 112 for providing the secondary fuel flow (fuel flow in line 112 providing fuel to the secondary combustion zone, see par. 35) to the combustor 30; and a fuel flow control device 112’ located along the secondary fuel supply line 112, the fuel flow control device 112’ configured to control the first state and the second state (the fuel flow device 112’ controls the flow rate, see par. 35; this is consistent with applicant par. 56, bottom, wherein the claimed fuel flow control device can be a valve).
Regarding claim 13, Fletcher discloses (see fig. 2) the fuel system comprising: a primary fuel supply line 110 having a primary fuel injector (see par. 33, middle and bottom, and par. 35 pointing out that fuel duct 110 is at the location of the primary combustion zone) at a forward end (at the location of line 110) of the combustor 30; and a secondary fuel supply line 112 having a secondary fuel injector (see par. 33, middle and bottom, and par. 35 pointing out that fuel duct 112 is at the location of the secondary combustion zone) along an axial length (see fig. 2) of the combustor 30.
Regarding claim 14, Fletcher discloses (see fig. 2) the steam system further comprising a steam injector for providing the steam flow from the steam supply line (line 72 is from boiler 60 that provides the steam; wherein the steam flow is in a steam injector, see par. 33, bottom) at a location (see fig. 2) along the axial length (see annotated figure above) of the combustor 30, wherein the steam injector and the secondary fuel injector (injector injecting fuel from line 112) are a combined fuel-steam injector (see par. 33; the two instant injectors can be separate or instead a single injector).
Regarding claim 15, Fletcher discloses (see fig. 2) the steam system 60,70,72 further comprising the steam supply line (see annotated figure above) having a steam injector (see par. 33) for providing the steam flow (flow of steam from boiler 60) along (see annotated figure below) the axial length (see annotated figure below) of the combustor 30, wherein the steam injector and the secondary fuel injector (injector providing fuel from line 112 into the secondary combustion zone discussed at par. 35) are separate (see par. 33, middle and bottom).
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claim(s) 5, 6 and 10-12 is/are rejected under 35 U.S.C. 103 as being unpatentable over Fletcher in view of Pub. No. US 2023/0392557 (Bulat), or alternatively over Fletcher in view of Baker and Asai as applied to claims 1 (regarding claims 5 and 6) and 9 (regarding claim 10) above, and further in view of Bulat .
Regarding claim 5, Fletcher discloses the current invention as claimed and discussed above. Fletcher further discloses (see fig. 2) the first flow rate (valve 112’ selectively controls the second fuel flow in line 112 and thus there is a first flow rate and a second flow rate; see par. 35) of the secondary fuel flow (fuel in duct 112) such that secondary fuel flow is provided to the combustor 30 (from line 112) in the first state. Fletcher does not disclose the secondary fuel flow is zero such that no secondary fuel flow is provided (i.e., Fletcher does not disclose valve 112’ has a closed or shutoff state).
Bulat teaches (see figs. 1 and 3) a gas turbine 10 and further teaches the secondary fuel flow is zero such that no secondary fuel flow is provided (when fuel flow control device 80 is closed (see par. 42, top) no fuel is provided to the combustor 36 (when the gas turbine engine is off before the engine has started; see par. 42, top).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Fletcher with the secondary fuel flow is zero such that no secondary fuel flow is provided as taught by Bulat in order to facilitate preventing fuel flow into the engine during shutoff so that the engine may be shut down (see par. 42, top). For example, if the steam system is not on, then the plant operator could choose not to operate the gas turbine with the secondary fuel flow from line 112.
Regarding claim 6, Fletcher discloses the current invention as claimed and discussed above. Fletcher as discussed above (see fig. 2) the first flow rate and the second flow rate (valve 112’ selectively controls the second fuel flow in line 112 and thus there is a first flow rate and a second flow rate; see par. 35). Fletcher does not explicitly disclose the second flow rate is greater than the first flow rate.
Bulat teaches (see figs. 1 and 3) teaches a second flow rate is greater than a first flow rate (when fuel flow control device 80 is closed (see par. 42, top) there is a first flow rate wherein there is no fuel is provided to the combustor 36 when the gas turbine engine is off before the engine has started for example; see par. 42, top; when the fuel flow control device 80 is not closed there is a second flow rate greater than the first flow rate).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Fletcher, or alternatively Fletcher in view of Baker and Asai, with the second flow rate is greater than the first flow rate as taught by Bulat in order to facilitate preventing fuel flow into the engine during shutoff so that the engine may be shut down (see par. 42, top). For example, if the steam system is not on, then the plant operator could choose not to operate the gas turbine with the secondary fuel flow from line 112.
Regarding claim 10, Fletcher discloses (see fig. 2) the current invention as claimed and discussed above. Fletcher discloses the fuel flow control device 112’ is open in the second state (valve 112’ selectively controls the second fuel flow in duct 112 and thus there is a there is a state wherein the valve is open; see par. 35). Fletcher does not disclose the fuel flow control device is closed in the first state (i.e., Fletcher does not disclose valve 112’ has a closed or shutoff state).
Bulat teaches (see figs. 1 and 3) a gas turbine 10 and further teaches a fuel flow control device 80 is closed (see par. 42, top) in a state (when the gas turbine engine is off before the engine has started; see par. 42, top).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Fletcher with the fuel flow control device is closed in the first state as taught by Bulat in order to facilitate preventing fuel flow into the engine during shutoff so that the engine may be shut down (see par. 42, top). For example, if the steam system is not on, then the plant operator could choose not to operate the gas turbine with the secondary fuel flow from line 112.
Regarding claims 11 and 12, Fletcher discloses the current invention as claimed and discussed above. Fletcher discloses (claim 11) placing the fuel system in the first state or the second state (valve 112’ selectively controls the second fuel flow in duct 112 and thus there is a first flow rate and a second flow rate associated with the first state and the second state, respectively, as discussed in the claim 1 analysis above; see par. 35). Fletcher does not disclose (claim 11) a controller configured to actuate the fuel flow control device, (claim 12) wherein the controller is configured to actuate the fuel flow control device based on a pressure of the steam system or a power output of the turbine engine.
Bulat teaches (see figs. 1 and 3) (claim 11) a controller 86 configured to actuate a fuel flow control device 80, (claim 12) wherein the controller 86 is configured to actuate the fuel flow control device 80 based on a power output of a turbine engine 10 (valve 80 is opened corresponding with power output demand of engine; see par. 42, top and middle).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Fletcher with (claim 11) a controller configured to actuate the fuel flow control device, (claim 12) wherein the controller is configured to actuate the fuel flow control device based on a power output of the turbine engine as taught by Bulat in order to facilitate reducing emissions while permitting the gas turbine engine of Fletcher in view Bulat an increase in power by adding more fuel.
Claim(s) 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Fletcher in view of Baker and Asai, as applied to claim 1 above, and further in view of Bulat and Pub. No.: US 2016/0053682 A1 (Page).
Regarding claim 7, Fletcher in view of Baker and Asai teach the current invention as claimed and discussed above. Fletcher does not explicitly disclose the steam system has an initial operating pressure, and the fuel system exhibits the second state based on a pressure of the steam system being at least five percent lower than the initial operating pressure.
Bulat teaches (see figs. 1 and 3) teaches a fuel system exhibits a state (when fuel flow control device 80 is closed (see par. 42, top) no fuel is provided to the combustor 36) (when the gas turbine engine is off before the engine has started for example; see par. 42, top).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Fletcher in view of Baker and Asai with the fuel system exhibits the second state as taught by Bulat in order to facilitate preventing fuel flow into the engine during shutoff so that the engine may be shut down (see par. 42, top). For example, if the steam system is not on, then the plant operator could choose not to operate the gas turbine with the secondary fuel flow from line 112.
Page teaches (see fig. 2) a gas turbine 150 and further teaches a steam system has an operating pressure (steam system 125,144 provides steam from heat recovery system 125 to combustor 158 of gas turbine 150; the steam from heat recovery system 125 may be have operating pressure levels from a low pressure level of 1 MPa to high level of 2.8 MPa as pointed out in par. 48, middle).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Fletcher in view of Baker, Asai and Bulat with the steam system has an operating pressure as taught by Page in order to facilitate efficient operation of the power plant of Fletcher in view of Baker, Asai, Bulat and Page. An operator of a power plant with a steam injected gas turbine balances many variables in order to operate the plant with minimal energy loss. For example, the steam pressure must be greater than the pressure in the combustor or else the steam won’t enter the combustor. However, a steam pressure that is too high may overly increase the steam flow rate. The ratio of steam flow rate to fuel flow rate should be kept within bounds for efficient operation of the gas turbine. This is knowledge of one of ordinary skill in the area of steam injected gas turbines (see Pertinent Prior Art section infra regarding a discussion of such knowledge).
Thus it would be reasonable for, during a snapshot of time when the gas turbine is initially operating at the high steam pressure of Fletcher in view of Baker, Asai, Bulat and Page, to reduce or shut-off the fuel flow with fuel flow control device 112’ (see fig. 2 of Fletcher) to avoid an improper ratio of fuel to steam or to avoid not arriving at higher gas turbine power levels that would normally be available with high pressure steam. Thus, a plant operator could manually shut off (as taught by Asai) the secondary fuel flow (this representing the flow rate of the second state) when the plant operator detects (as taught by Baker) the low steam pressure (as taught by Page) during monitoring of the steam pressure (as taught by Baker), the low steam pressure (i.e., 1.5 MPa) at least five percent lower than the initial operating pressure (i.e., 2.8 MPa).
Claim(s) 8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Fletcher in view of Baker and Asai.
Regarding claim 8, Fletcher discloses the current invention as claimed and discussed above. Fletcher further discloses a pressure (the pressure of the steam in boiler 60 and line 72; see par. 8, bottom) of the steam system 60,70,72. Fletcher does not disclose a sensor system configured to detect the pressure of the steam system.
Baker teaches (see fig.) a gas turbine 3 and further teaches a sensor system (device that senses the pressure of steam in line 1k; see col. 3, ll. 25-30) configured to detect a pressure of a steam system 1,1k.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Fletcher with a sensor system configured to detect the pressure of the steam system as taught by Baker in order to facilitate alerting the plant operator of the condition of the steam. For example, the steam in line 72 has to have a minimum pressure (i.e. it must be at least somewhat greater than the pressure in the combustor 30 or else the steam could not enter the combustor as discussed in Pertinent Prior Art section infra). Therefore if the steam was below this threshold, then the plant operator could not rely on the power output increase afforded by the steam injection (see par. 4, top, of Fletcher that demonstrates knowledge of one of ordinary skill).
The phrase “wherein the fuel system exhibits the first state based on the pressure of the steam system being above a predetermined value and the fuel system exhibits the second state based on the pressure of the steam system being at least five percent less than the predetermined value” is interpreted as intended use (i.e. this is an apparatus claim and there is not further structure recited in this phrase and thus the prior art need only be capable of performing the intended use). Combination Fletcher in view Baker and Asai is capable of performing the intended use. For example, the plant operator of the combination of the combination can monitor the steam pressure (see Baker col. 4, ll. 30-35 providing an example of the plant operator monitoring a steam pressure and taking an action at the time of a threshold of sufficient steam pressure). The plant operator of the combination can then exhibit the first and second states (i.e., provide a flow rate of the secondary fuel flow through duct 112 by adjusting valve 112’). Asai provides a teaching that a gas turbine plant operator may manually adjust a fuel flow rate to the gas turbine engine. For example, Asai teaches (see fig. 1) that a gas turbine plant (see par. 13) operator may manually adjust (see pars. 45, middle, and 53, bottom) a fuel flow rate (via shutoff and; or control valves 62,63,64,65) to the gas turbine engine combustor 3 (see par. 45 discussing the general concept of manual operation and par. 53 discussing manual control of fuel flow control devices 62-65). Therefore the first and second states can be exhibited as claimed.
Claim(s) 16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Fletcher, or in the alternative over Fletcher in view of Baker and Asai, as applied to claim 15 above, and further in view of US 5058374 (Bechlher).
Regarding claim 16, Fletcher discloses the current invention as claimed and discussed above. Fletcher does not disclose the separate fuel injector and the steam injector are provided in the same body.
Bechlher teaches (see fig. 3) a gas turbine (see abstract) and further teaches the general concept a separate fuel injector (fuel is injected from passage 27) and the steam injector (steam is injected from passage 21) are provided in the same body 18.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Fletcher with the separate fuel injector and the steam injector are provided in the same body for matters of convenience (see Bechlher col. 1, ll. 10-15), improved combustion efficiency (see col. 1, ll. 15-20) and reduced steam energy losses (see col. 1, ll. 40-45). This results in the instant two injectors disclosed by Fletcher being in the same body. One of ordinary skill is knowledgeable regarding such injector bodies (see Pertinent Prior Art infra).
Claim(s) 17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Fletcher, or in the alternative over Fletcher in view of Baker and Asai, as applied to claim 15 above, and further in view Pub. No. US 20180370651 A1 (Miller).
Regarding claim 17, Fletcher discloses the current invention as claimed and discussed above. Fletcher discloses (see fig. 2) introducing the steam flow (at lines 72,74) into the combustor 30; and introducing the secondary fuel flow (via line 112) into the combustor 30. Fletcher does not disclose introducing the secondary fuel flow based on a loss in pressure of the steam flow or a loss in power output of the turbine engine.
Miller teaches (see fig. 3) a gas turbine 200 and further teaches introducing a fuel flow (see pars. 102, middle, 107, middle, or 112, middle; fuel flow is increased to accommodate the loss of power) based on a loss in power output (see pars. 102, middle, 107, middle, or 112, middle) of the turbine engine 200.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Fletcher with introducing the secondary fuel flow based on a loss in power output of the turbine engine as taught by Miller in order to facilitate preventing a loss of electricity of provided by the generator of Fletcher (see par. 28, bottom) that would be caused by the slowing down of the gas turbine when the power loss occurs (see Miller par. 81, bottom). It is noted as general information that Fletcher can be an aeroderivative engine 10 (see par. 28, bottom) and this is consistent with Miller’s aviation engine 200 although this is not necessary.
Claim(s) 18-20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Fletcher in view of Baker, Asai and Miller as applied to claim 17 above, and further in view of Pub. No. US 2018/0328287 A1 (Moniz).
Regarding claim 18, Fletcher in view of Miller teach the current invention as claimed and discussed above. Fletcher discloses (see fig. 2) injecting (see e.g., par. 33, bottom and par. 35) the secondary fuel flow (via line 112) into the combustor 30. Fletcher does not disclose monitoring the pressure of the steam flow to generate a monitored pressure; monitoring a power output of the turbine engine to generate a monitored power output; detecting the loss in pressure of the steam flow when the monitored pressure is below a predetermined pressure value; detecting the loss in power output of the turbine engine when the monitored power output is below a predetermined power value; and the injecting the secondary fuel flow into the combustor is based on the detecting of the loss in pressure of the steam flow or based on the detecting of the loss in power output in the turbine engine or both.
Baker teaches monitoring the pressure of the steam flow (with steam pressure sensor, i.e., device, in line 1k; see col. 3, ll. 25-30) to generate a monitored pressure (the pressure represented by the “pressure signal” at col. 3, l. 27); detecting the loss in pressure (the pressure will fall; see col. 3, ll. 30-35; and when this fallen steam pressure signal is received by the boiler controller 16, the controller sends a signal 14a to request ramp up of gas turbine in order to generate more steam by creating more combustion air in line 9a; see col. 3, ll. 30-40) of the steam flow when the monitored pressure is below a predetermined pressure value (when the steam pressure falls below the current value this represents a steam dearth and that the steam turbine needs more steam in order for the combined cycle power plant of Baker to operate efficiently, see col. 1, l. 25).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Fletcher in view of Miller with monitoring the pressure of the steam flow to generate a monitored pressure; and detecting the loss in pressure of the steam flow when the monitored pressure is below a predetermined pressure value as taught by Baker in order to facilitate efficient operation of the combined cycle plant of the combination of Fletcher in view of Miller and Baker (see Baker col. 1, ll. 24-30 and . For example, monitoring for a loss of steam pressure would alert the plant operator of the combination that sufficient power augmentation by way of steam injection (see Fletcher par. 3) may not be available such that the operator could take corrective action (see Baker col. 3, ll. 25-30). This could also include using a steam turbine with the plant of the combination.
Moniz teaches (see fig. 1) a gas turbine 10 and further teaches monitoring a power output (see par. 16, bottom) of the turbine engine 10 to generate a monitored power output (that goes to the engine controller 320; see fig. 3).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Fletcher in view of Miller and Baker with monitoring a power output of the turbine engine to generate a monitored power output as taught by Moniz in order to facilitate improved engine operability, efficiency, and responsiveness (see Moniz par. 3, bottom and par. 4). For example a response with a fuel flow command can accommodate a loss of engine power (see Moniz par. 16, middle and bottom).
The teachings of Miller combined with Fletcher in the claim 17 analysis above include
detecting the loss in power output of the turbine engine when the monitored power output is below a predetermined power value. For Miller taught in the claim 17 analyses introducing a fuel flow based on a loss in power output (see pars. 102, middle, 107, middle, or 112, middle) of the turbine engine 200 wherein the Miller detected the loss of power when a pulse was given to the electric machine and the loss of power was when the power was below the power level before the instant pulse occurred (see, e.g., Miller par. 102).
injecting the secondary fuel flow into the combustor is based the detecting of the loss in power output in the turbine engine. For example Miller taught in the claim 17 analysis teaches introducing a fuel flow (see pars. 102, middle, 107, middle, or 112, middle; fuel flow is increased to accommodate the loss of power) based on a loss in power output (see pars. 102, middle, 107, middle, or 112, middle) of the turbine engine 200.
Regarding claim 19, claim 19 recites “injecting the secondary fuel flow into the combustor only occurs when the detected loss in pressure of the steam flow exists”. This can also be communicated as:
if the detected loss of pressure of the steam flow exists, then,
injecting the secondary fuel flow into the combustor may occur (but does not have to); and
if the detected loss of pressure of the steam flow does not exist, then,
injecting the secondary fuel flow into the combustor does not occur.
Therefore the instant claim 19 recitation is a conditional limitation and for a method claim (i.e., the steam injection does not occur if the condition of the detected pressure loss is not present), the BRI of a method claim does not include the step of the condition limitation if the claim does not required the condition limitation to occur (MPEP 2111.04 II.). Claim 19, by way of its dependency upon claim 18, requires the detection of the pressure loss (and the prior art teaches the instant detection and the injection of the secondary fuel flow in the claim 18 analysis above) and therefore the prior art is not required to address the scenario when the detected loss of pressure of the steam flow does not exist. Claim 18 is dependent overall on claim that is an apparatus claim. However, the structure for performing the limitation relating to the condition is not claimed (i.e., the fuel flow control device and the sensor system configured to detect a pressure of the steam are not claimed in claim 1,17,18) (MPEP 2111.04 II.). Therefore this analysis is proper.
Regarding claim 20, claim 20 recites “not injecting the secondary fuel flow into the combustor based on a monitored pressure being at or above the predetermined value”. This can also be communicated as:
if the monitored pressure is at or above the predetermined value (and thus there is not a detection of loss of pressure of the steam flow), then,
injecting the secondary fuel flow into the combustor does not occur.
Therefore the instant claim 20 recitation is a conditional limitation and for a method claim (i.e., the secondary fuel flow does not occur if the condition a detected pressure loss is not present), the BRI of a method claim does not include the step of the condition limitation if the claim does not required the conditional limitation to occur (MPEP 2111.04 II.). Claim 20, by way of its dependency upon claim 18, requires the detection of the pressure loss (and the prior art teaches the instant detection and the injection of the secondary fuel flow in the claim 18 analysis above) and therefore the prior art is not required to address the scenario when the detected loss of pressure of the steam flow does not exist. Claim 18 is dependent overall on claim that is an apparatus claim. However, the structure for performing the limitation relating to the condition is not claimed (i.e., the fuel flow control device and the sensor system configured to detect a pressure of the steam are not claimed in claim 1,17,18) (MPEP 2111.04 II.). Therefore this analysis is proper.
Pertinent Prior Art
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
steam pressure must be greater than combustor pressure for steam injection: US 20070214766 (par. 36); and
similar structure to applicant combustor: US 20130192249 (fig. 2);
maintaining a steam flow rate to fuel flow rate ratio improves emissions and efficiency: US 5357741 (col. 1, ll. 5-10 and col. 2, ll. 5-12), NPL Gas Turbines - A Handbook of Air, Land and Sea Applications (author Soares; page 609);
separate steam injector and fuel injector in same body: US 20220412563 (figs. 3 and 6), US 1988456 (fig. 2);
balancing steam pressure and steam flow rate; US 20070214766 (par. 36);
manually adjust fuel valve and steam valve: US 20130318974 (par. 34).
Correspondence
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MARC J AMAR whose telephone number is (571)272-9948. The examiner can normally be reached M-F 9:00-6:00.
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/MARC AMAR/Examiner, Art Unit 3741
/LORNE E MEADE/Primary Examiner, Art Unit 3741