Disclosure of Invention
The purpose of the present disclosure is to overcome the technical deficiencies, and provide a hybrid electric propulsion method for a three-shaft gas turbine engine, which realizes decoupling of the operating point of each component and the engine load, thereby optimizing the efficiency of the engine at the non-design point.
In order to achieve the above technical object, an aspect of the present disclosure provides a hybrid electric propulsion method for a three-shaft gas turbine engine, the three-shaft gas turbine engine including a gas generator and a power turbine, the gas generator including a high-pressure part and a low-pressure part, the high-pressure part including a high-pressure turbine, a high-pressure compressor, a high-pressure shaft, and a high-pressure shaft motor for controlling a rotation speed of the high-pressure shaft, the low-pressure part including a low-pressure turbine, a low-pressure compressor, a low-pressure shaft, and a low-pressure shaft motor for controlling a rotation speed of the low-pressure shaft, the hybrid electric propulsion method including:
obtaining component characteristic parameters of the gas turbine engine;
establishing a simulation model of the gas turbine engine based on the component characteristic parameters, the simulation model including an energy analysis module;
determining a corresponding relationship between a reduced rotational speed of the gas generator and a thermal efficiency of the gas turbine engine by adjusting a power of a gas generator motor, the gas generator motor comprising a high pressure shaft motor and/or a low pressure shaft motor, the reduced rotational speed of the gas generator comprising a reduced rotational speed of the high pressure shaft and a reduced rotational speed of the low pressure shaft, using the energy module of the simulation model;
and determining the optimal reduced rotating speed of the gas generator and the optimal power of the motor of the gas generator according to the corresponding relation between the reduced rotating speed of the gas generator and the thermal efficiency of the gas turbine engine.
Further, the gas turbine engine component characterization parameters include: pressure ratio and efficiency characteristics of the high pressure compressor, pressure ratio and efficiency characteristics of the low pressure compressor, expansion ratio and efficiency characteristics of the high pressure turbine, expansion ratio and efficiency characteristics of the low pressure turbine, and expansion ratio and efficiency characteristics of the power turbine.
Further, the energy analysis module is configured to calculate an energy flow, a,
Flow and irreversible loss conditions.
Further, the hybrid electric propulsion means that, when the gas turbine engine is in operation, the gas generator motor is used as a motor to provide input power to the high-pressure shaft and/or the low-pressure shaft, or the gas generator motor is used as a generator to extract output power from the high-pressure shaft and/or the low-pressure shaft, so as to actively adjust the reduced rotation speed of the gas generator.
Further, determining an optimal reduced rotational speed of the gas generator and an optimal power of the gas generator motor according to a corresponding relationship between the reduced rotational speed of the gas generator and a thermal efficiency of the gas turbine engine, comprising:
determining the reduced rotating speed of the gas generator corresponding to the optimal thermal efficiency as the optimal reduced rotating speed of the gas generator under the condition that the gas turbine engine is guaranteed not to exceed the rated working temperature, not to exceed the rated working rotating speed and the surge margin is not lower than the safety surge margin; determining the generator motor power corresponding to the optimal thermal efficiency as the optimal power
Further, the method further comprises:
and determining the optimal power of the gas generator motor under different specific atmospheric environments according to the optimal reduced rotating speed of the gas generator.
Further, the optimal power of the gas generator motor in said specific atmospheric environment needs to satisfy the following two conditions:
when the gas turbine engine is at 30% rated load, the thermal efficiency of the gas turbine engine is improved by more than 1%; and the number of the first and second groups,
and under the specific atmospheric environment, the gas turbine engine does not exceed the rated working temperature, does not exceed the rated working rotating speed, and has a surge margin not lower than a safety surge margin.
The technical scheme of this disclosure still provides a hybrid electric propulsion device of three-shaft gas turbine engine, the three-shaft gas turbine engine includes gas generator and power turbine, gas generator includes high-pressure part and low pressure part, the high-pressure part has high-pressure turbine, high-pressure compressor, high-pressure axle and the high-pressure axle motor of controlling the high-pressure axle rotational speed, the low pressure turbine has low-pressure turbine, low-pressure compressor, low-pressure axle and the low-pressure axle motor of controlling the low-pressure axle rotational speed, the hybrid electric propulsion controlling means includes:
an acquisition module for acquiring component characteristic parameters of the gas turbine engine;
a modeling module for building a simulation model of the gas turbine engine based on the component property parameters, the simulation model including an energy analysis module;
a first determining module, configured to determine a corresponding relationship between a reduced rotational speed of the gas generator and a thermal efficiency of the gas turbine engine by adjusting a power of a gas generator motor, the gas generator motor including a high-pressure shaft motor and/or a low-pressure shaft motor, the reduced rotational speed of the gas generator including the reduced rotational speed of the high-pressure shaft and the reduced rotational speed of the low-pressure shaft, using the energy module of the simulation model;
and the second determination module is used for determining the optimal reduced rotating speed of the gas generator and the optimal power of the motor of the gas generator according to the corresponding relation between the reduced rotating speed of the gas generator and the thermal efficiency of the gas turbine engine.
Further, the hybrid electric propulsion control device further comprises a third determination module, which is used for determining the optimal power of the gas generator motor under different specific atmospheric environments according to the optimal reduced rotating speed of the gas generator.
Compared with the prior art, the hybrid electric propulsion method of the three-shaft gas turbine engine disclosed by the invention has at least one or part of the following beneficial effects:
(1) the rotating speed of the gas generator (high-pressure shaft and low-pressure shaft) is decoupled from the load of the engine, and the rotating speed and the common working point of the gas generator (high-pressure shaft and low-pressure shaft) can be regulated within a certain range under the condition of ensuring the output power of the gas turbine engine to be certain by regulating the input power or the output power of the motor of the gas generator.
(2) By performing simulation, the effectiveness of the hybrid electric propulsion scheme can be verified.
(3) The present disclosure enables optimization of off-design point operating conditions, particularly gas turbine engine component efficiency and cyclic thermal efficiency at medium to low loads, reducing part count
Loss, effectively relieving the efficiency deterioration problem under the low load in the engine.
(4) The energy-saving effect of the hybrid electric propulsion system is not limited by battery capacity, and the performance of the engine at a non-design point is improved under the condition of ensuring the balance of power supply and demand, so that the hybrid electric propulsion system is suitable for high-power scenes such as ships, thermal power generation, main passenger planes and the like, the battery capacity in the hybrid electric propulsion system is effectively reduced, and the power density and the economy of the system are improved.
Detailed Description
In order to make the objects, technical solutions and advantages of the present disclosure more clearly understood, the present disclosure is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the disclosure and are not intended to limit the disclosure.
Gas turbine engines include gas turbines and aircraft engines, split shaft gas turbines and turboshaft engines generally include a gas generator including a combustor, a compressor, and a compressor turbine, and a power turbine. In operation, the compressor draws air into the interior of the gas turbine engine and compresses the air. The compressed air and fuel are mixed and combusted in the combustion chamber, the generated high-temperature and high-pressure gas pushes the turbine blades to rotate, one part of power is used for driving the power turbine to output power outwards, and the other part of power drives the compressor to rotate through the compressor turbine. Therefore, the output power of the gas turbine engine is highly coupled with the rotating speed of the compressor, and the working points of all the parts are in one-to-one correspondence with the output power according to the pneumatic and mechanical constraint relations among all the parts. According to the hybrid electric propulsion method, the decoupling of the working condition points of all parts and the load of the engine is realized, so that the efficiency of the engine at a non-design point is optimized.
Fig. 1 is a schematic view of a three-shaft gas turbine engine in an embodiment, as shown in fig. 1, including a gas generator including a combustor, a high-pressure compressor, a low-pressure compressor, a high-pressure turbine, and a low-pressure turbine, and a power turbine.
The high-pressure component is provided with a high-pressure compressor, a high-pressure turbine, a high-pressure shaft and a high-pressure shaft motor for controlling the rotating speed of the high-pressure shaft, and the low-pressure component is provided with a low-pressure compressor, a low-pressure turbine, a low-pressure shaft and a low-pressure shaft motor for controlling the rotating speed of the low-pressure shaft. Specifically, the high-pressure turbine drives the high-pressure compressor through the high-pressure shaft, and the low-pressure turbine drives the low-pressure compressor through the low-pressure shaft. The high-pressure shaft motor is arranged on the high-pressure shaft, the rotating speed of the high-pressure shaft can be controlled by controlling the input power or the output power of the high-pressure shaft motor, the low-pressure shaft motor is arranged on the low-pressure shaft, and the rotating speed of the low-pressure shaft can be controlled by controlling the input power or the output power of the low-pressure shaft motor.
FIG. 2 is a flow chart of a hybrid electric propulsion method for a three-shaft gas turbine engine according to an embodiment of the present disclosure.
As shown in fig. 2, a hybrid electric propulsion method of a three-shaft gas turbine engine includes:
step S1: obtaining component characteristic parameters of the gas turbine engine;
step S2: establishing a simulation model of the gas turbine engine based on the component characteristic parameters, the simulation model including an energy analysis module;
step S3: determining a corresponding relationship between a reduced rotational speed of the gas generator and a thermal efficiency of the gas turbine engine by adjusting a power of a gas generator motor, the gas generator motor comprising a high pressure shaft motor and/or a low pressure shaft motor, the reduced rotational speed of the gas generator comprising a reduced rotational speed of the high pressure shaft and a reduced rotational speed of the low pressure shaft, using the energy module of the simulation model;
step S4: and determining the optimal reduced rotating speed of the gas generator and the optimal power of the motor of the gas generator according to the corresponding relation between the reduced rotating speed of the gas generator and the thermal efficiency of the gas turbine engine.
The method utilizes an energy module of a simulation model, determines the corresponding relation between the reduced rotating speed of the gas generator and the heat efficiency of the gas turbine engine by adjusting the power of the motor of the gas generator, determines the influence rule of the reduced rotating speed of the gas generator on the whole engine performance, and further determines the optimal reduced rotating speed of the gas generator and the optimal power of the motor of the gas generator. The optimal power is input or extracted to the high-pressure shaft and/or the low-pressure shaft, the rotating speed of the high-pressure shaft and/or the low-pressure shaft is actively adjusted, the reduced rotating speed of the high-pressure shaft and the low-pressure shaft is optimized, and the decoupling of the rotating speed and the load of the gas generator of the gas turbine engine is realized. The optimal reduced rotating speed of the gas generator determined by the hybrid electric propulsion method of the three-shaft gas turbine engine can improve the heat efficiency of the gas turbine engine, breaks through the limitation of the energy-saving effect of the existing hybrid electric propulsion technology by the battery capacity, greatly improves the power density of the hybrid electric propulsion system, reduces the system cost, and improves the non-design point efficiency of the engine under the condition of ensuring the balance of power supply and demand.
In some embodiments, a hybrid electric propulsion method for a three-shaft gas turbine engine, comprises:
step S1: obtaining component characteristic parameters of the gas turbine engine.
Specifically, the high-pressure compressor, the low-pressure compressor, the high-pressure turbine, the low-pressure turbine and the power turbine component characteristic diagram can be determined by calculating fluid three-dimensional simulation or component characteristic experiments. From the component property map, a component property parameter of the gas turbine engine may be determined. Wherein the gas turbine engine component characteristic parameters may include: pressure ratio and efficiency characteristics of the high pressure compressor, pressure ratio and efficiency characteristics of the low pressure compressor, expansion ratio and efficiency characteristics of the high pressure turbine, expansion ratio and efficiency characteristics of the low pressure turbine, and expansion ratio and efficiency characteristics of the power turbine.
Step S2: establishing a simulation model of the gas turbine engine based on the component property parameters, the simulation model including an energy analysis module.
Specifically, on the basis of the component characteristics in step 1, a component-level simulation model is established, and an energy analysis module is added in the simulation model. The energy analysis module is configured to calculate an energy flow, a,
Flow and irreversible lossThe method is described. The components of the gas turbine engine may be a high pressure compressor, a low pressure compressor, a high pressure turbine, a low pressure turbine and a power turbine. FIG. 3 is a block diagram of a three-axis gas turbine component level simulation model and energy analysis module built in Simulink.
Step S3: determining a corresponding relationship between a reduced rotational speed of the gas generator and a thermal efficiency of the gas turbine engine by adjusting a power of a gas generator motor using the energy module of the simulation model, the reduced rotational speed of the gas generator including a reduced rotational speed of the high pressure shaft and a reduced rotational speed of the low pressure shaft.
Wherein the gasifier motor comprises a high pressure shaft motor and/or the low pressure shaft motor, and the reduced gasifier rotational speed comprises a reduced rotational speed of the high pressure shaft and/or a reduced rotational speed of the low pressure shaft.
Hybrid electric propulsion means that when the gas turbine engine works, the electric machine serves as a motor to provide input power to the high-pressure shaft and/or the low-pressure shaft, or the electric machine serves as a generator to extract power from the high-pressure shaft and/or the low-pressure shaft, so that the reduced rotating speed of the gas generator is actively adjusted, and decoupling control of the rotating speed of the high-pressure shaft and the rotating speed of the low-pressure shaft and the load of the engine is realized.
When the method is implemented, the energy analysis module of the simulation model constructed in the step S3 is used to change the reduced rotation speed NH of the high-pressure shaft by adjusting the input/output power of the high-pressure shaft and/or the low-pressure shaft
corAnd low spool reduced speed NL
corThereby calculating the reduced rotation speed NH of different high-pressure shafts
corAnd low spool reduced speed NL
corIn combination, the energy flow of the components of the gas turbine engine,
Flow and irreversible losses, and determining the correspondence between the reduced rotation speed of the gas generator and the thermal efficiency of said gas turbine engine.
Specifically, as shown in FIG. 4, a specific high-pressure shaft reduced speed is calculated for the gas turbine engine at 40% load condition, for exampleNH
corAnd low spool reduced speed NL
corIn combination, the energy flow of the components of the gas turbine engine,
Flow and irreversible loss conditions. Calculating different high-pressure shaft reduced rotating speeds NH by adjusting the motor powers of different gas generators
corAnd low spool reduced speed NL
corThe corresponding relationship between the reduced gas generator speed and the thermal efficiency of the gas turbine engine at 40% load of the gas turbine engine can be determined.
In some embodiments, the operating conditions of the gas turbine engine at 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100% load, respectively, may also be calculated to determine the correspondence between the reduced rotational speed of the gas generator and the thermal efficiency of the gas turbine engine at different loads.
Step S4: and determining the optimal reduced rotating speed of the gas generator and the optimal power of the motor of the gas generator according to the corresponding relation between the reduced rotating speed of the gas generator and the thermal efficiency of the gas turbine engine.
Specifically, under the condition that the gas turbine engine is guaranteed not to exceed a rated working temperature, not to exceed a rated working rotating speed and the surge margin is not lower than a safe surge margin, the reduced rotating speed of the gas generator corresponding to the optimal thermal efficiency is determined as the optimal reduced rotating speed of the gas generator; and determining the power of the generator motor corresponding to the optimal thermal efficiency as the optimal power.
In practice, the target reduced gasifier speed can be achieved by adjusting the gasifier motor power, thereby determining the optimum power of the gasifier motor.
FIG. 5 shows the energy analysis results for the three shaft gas turbine hybrid electric propulsion scheme at 40% load. As shown in fig. 5, the left graph is the situation before optimization, and the right graph is the situation after optimization, it can be seen that different folded rotation speeds of the high pressure shaft and/or the low pressure shaft can result in different thermal efficiencies of the engine. In the right diagram, the high-pressure shaft and the low-pressure shaft of the gas generator are controlled at the optimal reduced rotating speed, the motor of the gas generator is adjusted to the optimal power, and the heat efficiency of the engine is improved by 2%.
In other embodiments, the optimal reduced rotation speed of the gas generator and the optimal power of the motor of the gas generator under different loads can be determined according to the corresponding relationship between the reduced rotation speed of the gas generator under different loads and the thermal efficiency of the gas turbine engine, so that the high-pressure shaft and the low-pressure shaft are both at the optimal reduced rotation speed under different loads, the optimal reduced rotation speed can achieve the optimal efficiency under the condition that the engine is not over-heated or over-rotated and enough surge margin is ensured, the irreversible loss of a gas turbine engine system under different loads is reduced, and the oil consumption rate of an un-designed point is reduced.
The simulation calculation is carried out in a standard atmospheric environment, the engine load is reduced to a reduced parameter under a standard working condition, and the optimization result of the control rule is the corresponding optimal NH under different loadscor、NLcorThe value is obtained. Optimal NH at different reduced loads by gas generator motor during operation of gas turbinecor、NLcorAnd (4) closed-loop control.
In some embodiments, after determining the optimal power for the gas turbine engine gas generator motor, the hybrid electric propulsion method further comprises:
step S5: and determining the optimal power of the gas generator motor under different specific atmospheric environments according to the optimal reduced rotating speed of the gas generator. The atmospheric environment includes, but is not limited to, gas turbine engine inlet total temperature and total pressure, among others.
The optimal power of the generator motor for a specific atmospheric environment must satisfy the following two conditions:
when the gas turbine engine is at 30% rated load, the thermal efficiency of the gas turbine engine is improved by more than 1%; and
and under the atmospheric pressure condition, the gas turbine engine does not exceed the rated working temperature, does not exceed the rated working rotating speed, and the surge margin is not lower than the safety surge margin.
When the method is realized, the motor power of the high-pressure shaft and/or the low-pressure shaft is input, whether the reduced rotating speed of the gas generator meets the optimal reduced rotating speed or not is verified, the efficiency improving effect of the gas turbine under the reduced power is realized, whether the temperature is over-temperature and the rotation is over-high or not is judged, and whether the surge margin meets the requirement or not is verified.
Because the influence of the motor power on the engine performance and the reduced rotating speed of the gas generator is different for different atmospheric temperatures and atmospheric pressures, the reduced power of the different atmospheric temperatures and atmospheric pressures can be converted according to the following formula:
Where p is the output power, Tin、PinTotal gas turbine engine inlet temperature and total pressure.
Fig. 6 is a schematic structural view of a hybrid electric propulsion control apparatus of a three-shaft gas turbine engine, which includes, referring to fig. 6: the system comprises an acquisition module 201, a modeling module 202, a first determination module 203 and a second determination module 204.
An acquisition module for acquiring component characteristic parameters of the gas turbine engine;
a modeling module for building a simulation model of the gas turbine engine based on the component property parameters, the simulation model including an energy analysis module;
a first determining module, configured to determine a corresponding relationship between a reduced rotational speed of the gas generator and a thermal efficiency of the gas turbine engine by adjusting a power of a gas generator motor, the gas generator motor including a high-pressure shaft motor and/or a low-pressure shaft motor, the reduced rotational speed of the gas generator including the reduced rotational speed of the high-pressure shaft and the reduced rotational speed of the low-pressure shaft, using the energy module of the simulation model;
and the second determination module is used for determining the optimal reduced rotating speed of the gas generator and the optimal power of the gas generator motor according to the corresponding relation between the reduced rotating speed of the gas generator and the heat efficiency of the gas turbine engine.
Further, the hybrid electric propulsion control apparatus further includes:
and the third determining module is used for determining the optimal power of the gas generator motor under different specific atmospheric environments according to the optimal reduced rotating speed of the gas generator.
In the hybrid electric propulsion control device provided in the above embodiment, only the division of the functional modules is illustrated in the electric propulsion control, and in practical applications, the functions may be distributed to different functional modules as needed, that is, the internal structure of the device may be divided into different functional modules to complete all or part of the functions. In addition, the hybrid electric propulsion method of the three-shaft gas turbine engine provided by the embodiment belongs to the same concept, and specific implementation processes are detailed in the method embodiment and are not described again.
So far, the embodiments of the present disclosure have been described in detail with reference to the accompanying drawings. It is to be noted that, in the attached drawings or in the description, the implementation modes not shown or described are all the modes known by the ordinary skilled person in the field of technology, and are not described in detail. Further, the above definitions of the various elements and methods are not limited to the various specific structures, shapes or arrangements of parts mentioned in the examples, which may be easily modified or substituted by those of ordinary skill in the art.
From the above description, those skilled in the art should have a clear understanding of the present disclosure of gas turbine engine hybrid electric propulsion schemes based on gas generator speed decoupling.
In summary, the present disclosure determines the power of the gas generator motor and the engine components through simulation

And determining the influence rule of the loss corresponding relation on the whole machine performance, and determining the optimal power of the gas generator motor of the gas turbine engine. Namely byInputting or extracting optimal power to the high-pressure shaft and/or the low-pressure shaft, actively adjusting the rotating speed of the high-pressure shaft and/or the low-pressure shaft, optimizing the reduced rotating speed of the high-pressure shaft and the low-pressure shaft, and realizing the decoupling of the rotating speed and the load of the gas generator of the gas turbine engine. The hybrid electric propulsion method of the three-shaft gas turbine engine disclosed by the invention can break through the limitation of the energy-saving effect of the existing hybrid electric propulsion technology by the battery capacity, greatly improve the power density of the hybrid electric propulsion system, reduce the system cost and improve the efficiency of the non-design point of the engine under the condition of ensuring the balance of power supply and demand.