A transient control method for high pressure variable guide vane of dual-rotor combustion engine

Abstract

This application belongs to the field of aero-engine blade design, and specifically relates to a transient control method for high-pressure adjustable guide vanes in a dual-rotor gas turbine. The method includes: Step S1, acquiring characteristic data of the low-pressure compressor components in the gas generator state; Step S2, acquiring gas turbine operating parameters; Step S3, interpolating the low-pressure compressor efficiency from the low-pressure compressor component characteristic data based on the gas turbine operating parameters; Step S4, calculating the calculated value of the high-pressure compressor inlet total temperature based on the gas turbine operating parameters, the low-pressure compressor efficiency, and the entropy function relationship; Step S5, correcting the calculated value of the high-pressure compressor inlet total temperature based on the deviation between the measured value and the calculated value, obtaining a corrected value for the high-pressure compressor inlet total temperature; Step S6, acquiring transient criteria, and calculating the adjustable guide vane angle based on the corrected value for the high-pressure compressor inlet total temperature under transient conditions.

Description

Technical Field

[0001] This application belongs to the field of aero-engine blade design, and specifically relates to a transient control method for high-pressure adjustable guide vanes of a dual-rotor gas turbine. Background Technology

[0002] When generating electricity in isolated grids, the load driven by the gas turbine is a nonlinear electrical load with a fast change time, generally less than 0.1s. The load change is large, generally exceeding 25% of the rated load. In extreme cases, a short circuit fault can cause the load to change by 100%. This places high demands on the response speed of the gas turbine control parameters. The transient control speed and accuracy of the adjustable guide vane angle of the high-pressure compressor are also key considerations when formulating control laws.

[0003] For dual-rotor gas turbines, one common control method for the adjustable guide vanes of the high-pressure compressor during transient processes is to calculate the equivalent speed of the high-pressure rotor based on atmospheric temperature and then formulate a corresponding angle control law. Controlling the adjustable guide vane angle based on the equivalent high-pressure rotor speed calculated from atmospheric temperature has a relatively fast response speed and can adapt to the speed requirements of sudden load changes in isolated grid power generation. However, when component performance changes, or there are large differences in unit conditions, or large slip variations, the angle control error is large, affecting the stability and performance of the gas turbine. A second method is to calculate the equivalent high-pressure rotor speed based on the high-pressure compressor inlet section temperature and then formulate a corresponding angle control relationship. Controlling the adjustable guide vane angle based on the equivalent high-pressure rotor speed calculated from the high-pressure compressor inlet section temperature more directly reflects the working condition of the high-pressure compressor and can adapt to the control requirements of steady-state and slower adjustment speeds. However, when the load changes rapidly, the speed adjustment speed also increases. Due to the large time constant of the high-pressure compressor inlet section temperature sensor, temperature changes lag significantly. During sudden load increases, the angle control deviates, leading to a decrease in the working stability of the high-pressure compressor.

[0004] Therefore, there is an urgent need for a technical solution to overcome or mitigate at least one of the aforementioned defects in the existing technology. Summary of the Invention

[0005] The purpose of this application is to provide a transient control method for high-pressure adjustable guide vanes in a dual-rotor gas turbine to solve at least one problem existing in the prior art.

[0006] The technical solution of this application is:

[0007] A transient control method for high-pressure adjustable guide vanes in a dual-rotor gas turbine includes:

[0008] Step S1: Obtain the characteristic data of the low-pressure compressor component of the gas generator;

[0009] Step S2: Obtain gas turbine operating parameters;

[0010] Step S3: Interpolate the low-pressure compressor efficiency from the low-pressure compressor component characteristic data based on the gas turbine operating parameters;

[0011] Step S4: Calculate the total inlet temperature of the high-pressure compressor based on the gas turbine operating parameters, the efficiency of the low-pressure compressor, and the entropy function relationship.

[0012] Step S5: Based on the deviation between the measured value and the calculated value of the total inlet temperature of the high-pressure compressor, correct the calculated value of the total inlet temperature of the high-pressure compressor to obtain the corrected value of the total inlet temperature of the high-pressure compressor.

[0013] Step S6: Obtain transient criteria. Under transient conditions, calculate the converted speed of the high-pressure compressor based on the total inlet temperature correction value of the high-pressure compressor. Then, interpolate the adjustable guide vane angle under the current converted speed of the high-pressure compressor based on the control law of the converted speed of the high-pressure compressor and the adjustable guide vane angle.

[0014] In at least one embodiment of this application, in step S1, the characteristic data of the low-pressure compressor component includes low-pressure speed-to-pressure ratio characteristic data and low-pressure speed-to-efficiency characteristic data.

[0015] In at least one embodiment of this application, in step S2, the gas turbine operating parameters include inlet air temperature, low-pressure speed, low-pressure ratio, high-pressure inlet air temperature, and high-pressure speed.

[0016] In at least one embodiment of this application, in step S3, the low-pressure compressor efficiency is interpolated from the low-pressure compressor component characteristic data based on the low-pressure rotational speed and the low-pressure ratio.

[0017] In at least one embodiment of this application, step S4, calculating the total inlet temperature of the high-pressure compressor based on the gas turbine operating parameters, the low-pressure compressor efficiency, and the entropy function relationship, includes:

[0018] Substitute the intake air temperature into the entropy function calculation formula to calculate the inlet entropy function value;

[0019] Substitute the low pressure ratio and the inlet entropy function value into the variable specific heat isentropic adiabatic equation to calculate the outlet entropy function value;

[0020] Substitute the outlet entropy function value into the piecewise fitting formula of temperature versus entropy function to calculate the outlet isentropic adiabatic temperature.

[0021] Substitute the intake temperature into the enthalpy-temperature piecewise fitting formula to calculate the enthalpy value corresponding to the intake temperature.

[0022] Substitute the outlet isentropic adiabatic temperature into the enthalpy-temperature piecewise fitting formula to calculate the enthalpy value corresponding to the outlet isentropic adiabatic temperature.

[0023] The enthalpy value corresponding to the calculated total inlet temperature of the high-pressure compressor is calculated based on the enthalpy value corresponding to the inlet temperature, the enthalpy value corresponding to the isentropic adiabatic temperature of the outlet, and the efficiency of the low-pressure compressor.

[0024] Substitute the enthalpy value corresponding to the calculated total inlet temperature of the high-pressure compressor into the piecewise fitting formula of temperature versus enthalpy to calculate the calculated total inlet temperature of the high-pressure compressor.

[0025] In at least one embodiment of this application, step S5, based on the deviation between the measured value and the calculated value of the total inlet temperature of the high-pressure compressor, corrects the calculated value of the total inlet temperature of the high-pressure compressor to obtain a corrected value of the total inlet temperature of the high-pressure compressor, including:

[0026] When the test engine slows down to the preset speed, the deviation data of the measured value and the calculated value of the total inlet temperature of the high-pressure compressor at each high-pressure speed during the steady state process are obtained.

[0027] The correction amount is interpolated from the deviation data based on the high-pressure rotational speed.

[0028] The calculated total inlet temperature of the high-pressure compressor is corrected based on the correction amount to obtain the corrected value of the calculated total inlet temperature of the high-pressure compressor.

[0029] In at least one embodiment of this application, in step S6, the transient criterion is: the high-pressure speed is greater than the set value Const1, and the sudden load is greater than the set value Const2.

[0030] In at least one embodiment of this application, step S7 is further included: determining the angle deviation limit and obtaining the transient control angle of the high-pressure adjustable guide vane after amplitude limiting.

[0031] In at least one embodiment of this application, the angle deviation is limited to the following: the deviation amplitude between the transient control angle of the high-pressure adjustable guide vane calculated based on the correction value of the total inlet temperature of the high-pressure compressor and the transient control angle of the high-pressure adjustable guide vane calculated based on the test value of the total inlet temperature of the high-pressure compressor is not greater than the set value Const3.

[0032] In at least one embodiment of this application, ...

[0033] The invention has at least the following beneficial technical effects:

[0034] This application presents a transient control method for high-pressure adjustable guide vanes in a dual-rotor gas turbine. Based on characteristic data of the low-pressure compressor components obtained from gas generator tests, the method calculates the total inlet temperature of the high-pressure compressor in real time. It then corrects the calculated temperature at the corresponding speed based on the measured total inlet temperature of the high-pressure compressor at typical steady-state speeds during the previous test's 1.0-speed acceleration from idle to high speed. Compared to controlling the adjustable guide vane angle of the high-pressure compressor based on the inlet temperature T0, this invention solves the problem of reduced angle control accuracy caused by performance changes due to component performance degradation, differences in turbine state, and slip variations. The calculated temperature of this invention is real-time, avoiding the problem of angle control lag caused by the large time constant of the high-pressure compressor inlet test total temperature sensor, which affects the gas turbine's operational stability, as is often the case when using high-pressure compressor inlet test total temperature control for transient processes. Attached Figure Description

[0035] Figure 1 This is a flowchart of a transient control method for high-pressure adjustable guide vanes in a dual-rotor gas turbine according to one embodiment of this application. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0037] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this application.

[0038] The following is in conjunction with the appendix Figure 1 This application will be described in further detail.

[0039] This application provides a transient control method for high-pressure adjustable guide vanes in a dual-rotor gas turbine, comprising the following steps:

[0040] Step S1: Obtain the characteristic data of the low-pressure compressor component of the gas generator;

[0041] Step S2: Obtain gas turbine operating parameters;

[0042] Step S3: Interpolate the low-pressure compressor efficiency from the low-pressure compressor component characteristic data based on the gas turbine operating parameters;

[0043] Step S4: Calculate the total inlet temperature of the high-pressure compressor based on the gas turbine operating parameters, the efficiency of the low-pressure compressor, and the entropy function relationship.

[0044] Step S5: Based on the deviation between the measured value and the calculated value of the total inlet temperature of the high-pressure compressor, correct the calculated value of the total inlet temperature of the high-pressure compressor to obtain the corrected value of the total inlet temperature of the high-pressure compressor.

[0045] Step S6: Obtain transient criteria. Under transient conditions, calculate the equivalent speed of the high-pressure compressor based on the correction value of the total inlet temperature of the high-pressure compressor. Then, interpolate the adjustable guide vane angle at the current equivalent speed of the high-pressure compressor based on the control law of the equivalent speed of the high-pressure compressor and the adjustable guide vane angle.

[0046] The transient control method for high-pressure adjustable guide vanes of the dual-rotor gas turbine of this application firstly involves obtaining characteristic data of the low-pressure compressor components in the state of the gas generator in step S1, including low-pressure speed-pressure ratio characteristic data and low-pressure speed-efficiency characteristic data, and formulating a characteristic table of the low-pressure compressor components based on the characteristic data of the low-pressure compressor components.

[0047] In one embodiment of this application, after characteristic processing, at least 20 points of overvoltage ratio and efficiency are retained on each speed line, and the interval between two speed lines is controlled to be no greater than 0.1, see Table 1.

[0048] Table 1

[0049]

[0050] The characteristic data of the low-pressure compressor components in Table 1 are presented in tabular form as pressure ratio and efficiency at different speeds. The relationship between speed and pressure ratio is shown in Table 2, and the relationship between speed and efficiency is shown in Table 3.

[0051] Table 2

[0052]

[0053] Table 3

[0054]

[0055] In the transient control method for high-pressure adjustable guide vanes of the dual-rotor gas turbine of this application, in step S2, during the operation of the gas turbine, operating parameters such as inlet air temperature, low-pressure speed, low-pressure ratio, high-pressure inlet air temperature, and high-pressure speed are measured.

[0056] Furthermore, in step S3, the low-pressure compressor efficiency is interpolated from Tables 2 and 3 based on the low-pressure speed and low-pressure ratio.

[0057] In this embodiment, specifically, interpolation is performed based on the low-pressure speed and low-pressure ratio during the operation of the entire machine. For example, if the low-pressure speed is 0.65 and the low-pressure ratio is 1.12, then first, 20 pressure ratios below the 0.65 speed line are interpolated from Table 2 (see Table 4), and then the β value of 0.05 when the low-pressure ratio is 1.12 is interpolated from Table 4; 20 efficiencies below the 0.65 speed line are interpolated from Table 3 (see Table 5), and then the efficiency when the β value is 0.05 is interpolated from Table 5. It is 0.9058.

[0058] Table 4

[0059]

[0060] Table 5

[0061]

[0062] Then, in step S4, the calculation process for the total inlet temperature of the high-pressure compressor includes:

[0063] Substitute the intake air temperature into the entropy function calculation formula to calculate the inlet entropy function value;

[0064] When the temperature T < 800K, the entropy function is calculated using formula (1); when the temperature T ≥ 800K, the entropy function is calculated using formula (2).

[0065] (1);

[0066] (2);

[0067] In this embodiment, the intake air temperature T0 is 288.15K. Substituting this into the entropy function calculation formula, the inlet entropy function value is obtained. ;

[0068] Substitute the low pressure ratio and the inlet entropy function value into the variable specific heat isentropic adiabatic equation to calculate the outlet entropy function value.

[0069] The isentropic adiabatic equation with variable specific heat is:

[0070] (3);

[0071] low pressure ratio The value is 1.12. and Substitute into formula (3) to calculate the export entropy function value. It is 10.12941.

[0072] Substituting the outlet entropy function value into the piecewise fitting formula (4) for temperature versus entropy function, the outlet isentropic adiabatic temperature is calculated. It is 297.8K;

[0073] (4);

[0074] Substitute the intake temperature into the enthalpy-temperature piecewise fitting formula to calculate the enthalpy value corresponding to the intake temperature; substitute the outlet isentropic adiabatic temperature into the enthalpy-temperature piecewise fitting formula to calculate the enthalpy value corresponding to the outlet isentropic adiabatic temperature.

[0075] (5);

[0076] (6);

[0077] The enthalpy values ​​at different temperatures are calculated using formulas (5) and (6). The enthalpy value for an inlet temperature T0 of 288.15 K is calculated to be 287.87 kJ / kg, and the isentropic adiabatic temperature at the outlet is... The ideal enthalpy H is 297.8K. 25,i It is 297.54 kJ / kg.

[0078] The enthalpy value corresponding to the calculated total inlet temperature of the high-pressure compressor is calculated based on the enthalpy value corresponding to the inlet temperature, the enthalpy value corresponding to the isentropic adiabatic temperature at the outlet, and the efficiency of the low-pressure compressor.

[0079] (7);

[0080] The enthalpy H corresponding to the calculated total inlet temperature of the high-pressure compressor is calculated according to formula (7). 25 It is 298.55 kJ / kg.

[0081] Substitute the enthalpy value corresponding to the calculated total temperature at the inlet of the high-pressure compressor into the temperature-enthalpy piecewise fitting formula (8) to calculate the calculated total temperature at the inlet of the high-pressure compressor.

[0082] (8);

[0083] The calculated total inlet temperature T of the high-pressure compressor is obtained according to formula (8). t25c It is 298.45K.

[0084] The transient control method for high-pressure adjustable guide vanes in the dual-rotor gas turbine of this application includes the following steps in step S5: Correcting the calculated total inlet temperature of the high-pressure compressor.

[0085] When the test engine slows down to the preset speed, the deviation data of the measured value and the calculated value of the total inlet temperature of the high-pressure compressor at each high-pressure speed during the steady state process are obtained.

[0086] The correction amount is interpolated from the deviation data based on the high-pressure rotational speed;

[0087] The calculated total inlet temperature of the high-pressure compressor is corrected based on the correction amount, resulting in the corrected value for the calculated total inlet temperature of the high-pressure compressor.

[0088] In this embodiment, during the standby state before startup, the control system automatically updates the test values ​​T corresponding to each high-pressure speed during the steady-state process when the engine reached 1.0 high-pressure speed in the previous test (if 1.0 high-pressure speed was not reached, the most recent 1.0 high-pressure speed was used). t25 and calculated value T t25c At the same time, the difference T between the two t25 -T t25c denoted as ∆T t25 Table 6 shows examples of temperature differences at different high pressure speeds. Based on the linear interpolation in Table 6, the correction amount at a certain speed during the transient process of the gas turbine is obtained. The interpolation speed step size is no greater than 0.05, and the correction amount of speed and temperature between each interpolation speed is taken as close as possible.

[0089] Table 6

[0090]

[0091] T corresponding to a certain speed t25 The calculation correction is shown in formula (9):

[0092] (9);

[0093] In the transient control method for high-pressure adjustable guide vanes of the dual-rotor gas turbine of this application, in step S6, a transient criterion is obtained. The high-pressure speed is greater than the set value Const1, and the sudden load is greater than the set value Const2 as the criterion for the transition from steady state to transient process. Under the transient condition, the high-pressure compressor conversion speed is calculated based on the correction value of the total inlet temperature of the high-pressure compressor and the high-pressure speed. Then, the adjustable guide vane angle α2 under the current high-pressure compressor conversion speed is interpolated based on the calculated high-pressure compressor conversion speed and the control law of adjustable guide vane angle.

[0094] Finally, the process also includes: Step S7, determining the angle deviation limit and obtaining the transient control angle of the high-pressure adjustable guide vane after amplitude limiting. The angle deviation limit is: the deviation amplitude between the transient control angle of the high-pressure adjustable guide vane calculated based on the correction value of the total inlet temperature of the high-pressure compressor and the transient control angle of the high-pressure adjustable guide vane calculated based on the test value of the total inlet temperature of the high-pressure compressor is not greater than the set value Const3.

[0095] This application discloses a transient control method for high-pressure adjustable guide vanes in a dual-rotor gas turbine. t25 The sensor has a large time constant, resulting in a lag in transient process measurements and affecting the accuracy of transient measurements. This application derives component characteristics from gas generator tests and calculates T using an interpolation program. t25c The calculation results can represent the performance of the low-pressure compressor components during gas turbine operation, and also have the technical advantage of real-time operation, which can improve the stability of high-pressure transient process control and angle control accuracy during sudden load changes in the gas turbine. Controlling the α2 angle based on T0 in the transient process requires consideration of the effects of component performance degradation, differences in turbine state, and changes in dual-rotor slip, necessitating continuous improvement and involving a large workload. This application, however, uses T based on the gas turbine's steady-state speed. t25 Real-time correction calculation T t25c The technical advantage is that it can adaptively correct the calculated total temperature at the inlet of the high-pressure compressor based on the performance degradation of components, differences in the condition of the components, and changes in the slip of the dual rotors, which not only improves the accuracy of transient angle control, but also improves working efficiency.

[0096] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A transient control method for high-pressure adjustable guide vanes in a dual-rotor gas turbine, characterized in that, include: Step S1: Obtain the characteristic data of the low-pressure compressor component of the gas generator; Step S2: Obtain gas turbine operating parameters; Step S3: Interpolate the low-pressure compressor efficiency from the low-pressure compressor component characteristic data based on the gas turbine operating parameters; Step S4: Calculate the total inlet temperature of the high-pressure compressor based on the gas turbine operating parameters, the efficiency of the low-pressure compressor, and the entropy function relationship. Step S5: Based on the deviation between the measured value and the calculated value of the total inlet temperature of the high-pressure compressor, correct the calculated value of the total inlet temperature of the high-pressure compressor to obtain the corrected value of the total inlet temperature of the high-pressure compressor. Step S6: Obtain transient criteria. Under transient conditions, calculate the converted speed of the high-pressure compressor based on the total inlet temperature correction value of the high-pressure compressor. Then, interpolate the adjustable guide vane angle under the current converted speed of the high-pressure compressor based on the control law of the converted speed of the high-pressure compressor and the adjustable guide vane angle.

2. The transient control method for high-pressure adjustable guide vanes of a dual-rotor gas turbine according to claim 1, characterized in that, In step S1, the characteristic data of the low-pressure compressor component includes low-pressure speed-to-pressure ratio characteristic data and low-pressure speed-to-efficiency characteristic data.

3. The transient control method for high-pressure adjustable guide vanes of a dual-rotor gas turbine according to claim 2, characterized in that, In step S2, the gas turbine operating parameters include inlet air temperature, low-pressure speed, low-pressure ratio, high-pressure inlet air temperature, and high-pressure speed.

4. The transient control method for high-pressure adjustable guide vanes of a dual-rotor gas turbine according to claim 3, characterized in that, In step S3, the low-pressure compressor efficiency is interpolated from the low-pressure compressor component characteristic data based on the low-pressure speed and the low-pressure ratio.

5. The transient control method for high-pressure adjustable guide vanes of a dual-rotor gas turbine according to claim 4, characterized in that, In step S4, the calculated value of the total inlet temperature of the high-pressure compressor is calculated based on the gas turbine operating parameters, the low-pressure compressor efficiency, and the entropy function relationship, including: Substitute the intake air temperature into the entropy function calculation formula to calculate the inlet entropy function value; Substitute the low pressure ratio and the inlet entropy function value into the variable specific heat isentropic adiabatic equation to calculate the outlet entropy function value; Substitute the outlet entropy function value into the piecewise fitting formula of temperature with entropy function to calculate the outlet isentropic adiabatic temperature. Substitute the intake temperature into the enthalpy-temperature piecewise fitting formula to calculate the enthalpy value corresponding to the intake temperature. Substitute the outlet isentropic adiabatic temperature into the enthalpy-temperature piecewise fitting formula to calculate the enthalpy value corresponding to the outlet isentropic adiabatic temperature. The enthalpy value corresponding to the calculated total inlet temperature of the high-pressure compressor is calculated based on the enthalpy value corresponding to the inlet temperature, the enthalpy value corresponding to the isentropic adiabatic temperature of the outlet, and the efficiency of the low-pressure compressor. Substitute the enthalpy value corresponding to the calculated total inlet temperature of the high-pressure compressor into the piecewise fitting formula of temperature versus enthalpy to calculate the calculated total inlet temperature of the high-pressure compressor.

6. The transient control method for high-pressure adjustable guide vanes of a dual-rotor gas turbine according to claim 5, characterized in that, In step S5, based on the deviation between the measured and calculated total inlet temperature of the high-pressure compressor, the calculated total inlet temperature of the high-pressure compressor is corrected to obtain the corrected value of the calculated total inlet temperature of the high-pressure compressor, including: When the test engine slows down to the preset speed, the deviation data of the measured value and the calculated value of the total inlet temperature of the high-pressure compressor at each high-pressure speed during the steady state process are obtained. The correction amount is interpolated from the deviation data based on the high-pressure rotational speed. The calculated total inlet temperature of the high-pressure compressor is corrected based on the correction amount to obtain the corrected value of the calculated total inlet temperature of the high-pressure compressor.

7. The transient control method for high-pressure adjustable guide vanes of a dual-rotor gas turbine according to claim 6, characterized in that, In step S6, the transient criterion is: the high-pressure speed is greater than the set value Const1, and the sudden load is greater than the set value Const2.

8. The transient control method for high-pressure adjustable guide vanes of a dual-rotor gas turbine according to claim 1, characterized in that, It also includes step S7, determining the angle deviation limit, and obtaining the transient control angle of the high-pressure adjustable guide vane after amplitude limiting.

9. The transient control method for high-pressure adjustable guide vanes of a dual-rotor gas turbine according to claim 8, characterized in that, The angle deviation limit is: the deviation amplitude between the transient control angle of the high-pressure adjustable guide vane calculated based on the correction value of the total inlet temperature of the high-pressure compressor and the transient control angle of the high-pressure adjustable guide vane calculated based on the test value of the total inlet temperature of the high-pressure compressor shall not exceed the set value Const3.

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