Turbine characteristic calculation method, system and device

Abstract

The present application belongs to the technical field of control, and particularly relates to a turbine characteristic calculation method, system and device, aiming to solve the problems of low precision, excessive calculation amount, not considering the shape characteristics of the characteristic curve cluster itself, and not performing targeted analysis to cause interpolation error of the existing turbine characteristic interpolation method. The present application comprises: reconstructing the relative conversion speed-expansion ratio characteristic curve of the turbine into equidistant data and forming a plurality of preliminary beta auxiliary lines; connecting the data points obtained by reconstruction in the equidistant data and the corresponding conversion flow and isentropic efficiency according to the same serial number marked in the relative conversion speed-expansion ratio characteristic curve of the turbine to obtain a plurality of beta auxiliary lines; collecting turbine working condition parameters and converting them into the current working condition relative conversion speed N cor and the current working condition expansion ratio to construct the Lagrange interpolation polynomial of the kth point, obtain the current working condition characteristic curve and the current working condition beta auxiliary line; and performing interpolation on the target point to obtain the current working condition turbine characteristic.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of control, and particularly relates to a turbine characteristic calculation method, system and equipment. BACKGROUND

[0002] A turbine is a core component in a gas turbine power generation system. In order to accurately control the turbine speed, a working model of the turbine needs to be established. In order to establish the working model of the turbine, the performance parameters (including flow, output power, efficiency, etc.) of the turbine under different working conditions (including inlet temperature, inlet pressure, outlet pressure, speed) need to be accurately obtained. According to the working principle of the turbine, the turbine characteristics obtained under different turbine inlet temperature and inlet pressure conditions are different, that is, the obtained turbine characteristics are not universal.

[0003] In order to solve the problem of universality of turbine characteristics, Claus Riegler and others proposed a calculation method of conversion parameters based on the similarity criterion of the flow field for turbine component characteristics, and plotted the conversion parameters into characteristic curves. In actual work, the working environment of the turbine often differs from the design condition, and the performance of the turbine will change when the turbine works under different temperatures and pressures, and the characteristic curves show different postures. In the design and test of the turbine, only the performance under part of the working conditions is simulated to form part of the characteristic curves. Therefore, how to calculate the turbine performance at the non-design working condition point by using the known characteristic curves has become a problem to be solved.

[0004] At present, scholars at home and abroad have proposed many methods for calculating non-design working condition points. Most of the current methods use the characteristic curves constructed by known data to calculate the target working condition characteristics by exponential expansion or interpolation, but there are problems such as insufficient accuracy and large amount of calculation. The existing invention patent CN116090236 uses a linear interpolation method, which has low interpolation accuracy. CN112100848A and CN110321586 use all known data for interpolation, which improves the accuracy, but the amount of calculation is too large, and the former needs to fit the speed curve after constructing the characteristic curve and then calculate the target characteristic point, which is too complex. At the same time, the actual turbine characteristic curve cluster may appear the phenomenon of intersection, and using all the data for interpolation without paying attention to the trend of the characteristic curve will cause large errors. Especially in the case of large range of turbine working condition change, too high order of interpolation polynomial will cause the appearance of Runge phenomenon at the edge of the curve, which will greatly affect the interpolation accuracy. SUMMARY

[0005] In order to solve the problems in the prior art, that is, the existing turbine characteristic calculation method, the calculation amount is large, the calculation of the target characteristic point is too complex, the error is too high, and the high order of the interpolation polynomial in the case of a large change range of the turbine working condition will cause the edge of the curve to appear the Runge phenomenon, which has a great influence on the interpolation accuracy, the present application provides a turbine characteristic calculation method, the method comprises:

[0006] The maximum expansion ratio π max and the minimum expansion ratio π min of each speed line on the relative conversion speed-expansion ratio characteristic curve of the turbine are selected as upper and lower limits respectively, and are reconstructed into equidistant data according to equal expansion ratio intervals and form a plurality of preliminary β auxiliary lines, wherein each data point in the reconstructed equidistant data has a serial number (i, j), i represents the characteristic curve number, and j represents the data point number;

[0007] The data points obtained by reconstruction in the equidistant data and the corresponding conversion flow and isentropic efficiency are connected according to the same serial number marked in the relative conversion speed-expansion ratio characteristic curve of the turbine, and a plurality of β auxiliary lines are obtained;

[0008] The turbine working condition parameters are collected and converted into the current working condition relative conversion speed N cor and the current working condition expansion ratio π, based on the relative conversion speed-expansion ratio characteristic curve with a plurality of β auxiliary lines, a Lagrange interpolation polynomial of the kth data point is constructed, the intersection point in the relative conversion speed-expansion ratio characteristic curve of the turbine is searched, the original characteristic curve is grouped according to the size of the relative conversion speed and the position of the intersection point in the curve, the corresponding group of the turbine is confirmed according to the current working condition relative conversion speed, the interpolation is carried out by using the quadratic or cubic Lagrange method, and the current working condition characteristic curve is obtained;

[0009] According to the relative position of the expansion ratio of the current working condition in the relative conversion speed-expansion ratio characteristic curve, an interpolation method other than the Lagrange interpolation is used for interpolation, and the current working condition characteristic curve and the current working condition β auxiliary line are obtained;

[0010] The target points in the current working condition characteristic curve and the current working condition β auxiliary line are interpolated, and the current working condition turbine characteristic is obtained.

[0011] In some preferred embodiments, the collection of turbine working condition parameters and the conversion into the current working condition relative conversion speed N cor and the current working condition expansion ratio π are as follows:

[0012]

[0013] Wherein, P Tin represents the turbine inlet pressure, P Tout represents the turbine outlet pressure, N refrepresents the turbine design point speed, T ref represents the turbine design point speed, T in represents the turbine design point speed, T std represents the standard temperature.

[0014] In some preferred embodiments, the Lagrange interpolation polynomial L k (π) is:

[0015]

[0016] wherein π represents the current operating condition expansion ratio, π k represents the current operating condition expansion ratio of the kth point, π k+1 represents the current operating condition expansion ratio of the k+1th point, π k-1 represents the current operating condition expansion ratio of the k-1th point, π m represents the current operating condition expansion ratio of the mth data point, and m represents the number of data points participating in the interpolation calculation for each β auxiliary line.

[0017] In some preferred embodiments, the method for obtaining the current operating condition characteristic curve and the current operating condition β auxiliary line is:

[0018] Based on the Lagrange interpolation polynomial L k (π) of the kth point, the interpolation coordinate point corresponding to the conversion flow G cor,j and the isentropic efficiency η j of the jth β auxiliary line are calculated:

[0019]

[0020] wherein π j represents the current operating condition expansion ratio of the jth point, η k represents the isentropic efficiency corresponding to the kth point.

[0021] The intersection point between the original characteristic curves and the two original characteristic curves N a and N b (a

[0022] According to the relationship between the relative conversion speed N cor of the current operating condition and the region (N1~N n ) surrounded by the original characteristic curves, interpolation is performed, specifically:

[0023] If the relative conversion speed N cor of the current operating condition is less than the region surrounded by the original characteristic curves, i.e. N corN1 represents the relative converted speed corresponding to the first original characteristic curve, N n represents the relative converted speed corresponding to the last original characteristic curve, and m = a data points on each β auxiliary line are used for interpolation calculation, and a β auxiliary lines between N1 and N a are selected to perform Lagrange interpolation calculation:

[0024]

[0025] If the relative converted speed N of the current working condition cor is within the area surrounded by the original characteristic curves, i.e. N1≤N cor ≤N n , m = n data points on each β auxiliary line are used for interpolation calculation, and all β auxiliary lines are selected to perform Lagrange interpolation calculation:

[0026]

[0027] If the relative converted speed N of the current working condition cor is greater than the area surrounded by the original characteristic curves, i.e. N cor >N n , n-b+1 β auxiliary lines between N b and N n are selected to perform Lagrange interpolation calculation:

[0028]

[0029] After the Lagrange interpolation is performed, the current working condition characteristic curve and the current working condition β auxiliary line are obtained.

[0030] In some preferred embodiments, the target point in the current working condition characteristic curve and the current working condition β auxiliary line is once interpolated to obtain the current working condition turbine characteristic, specifically:

[0031] In the current working condition characteristic curve, the target point is selected, the expansion ratio π corresponding to the target point is taken as the interpolation point abscissa, and the data points on the current working condition characteristic curve corresponding to the interpolation point abscissa are represented as π i , i = 1, 2, …, j, from small to large according to the expansion ratio:

[0032] According to the relationship between the interpolation point abscissa and the current working condition characteristic curve, secondary Lagrange interpolation is performed;

[0033] When π≤π1 or π≥π j , i.e. the expansion ratio corresponding to the target point is outside the current working condition characteristic curve, linear Lagrange interpolation is performed using the two data points at the endpoints:

[0034]

[0035]

[0036] When π1< π ≤ π2or π j-1 ≤ π < π j , use three data points close to the endpoints for quadratic Lagrange interpolation:

[0037] The quadratic Lagrange interpolation when π1< π ≤ π2is:

[0038]

[0039] The quadratic Lagrange interpolation when π j-1 ≤ π < π j is:

[0040]

[0041] When π2< π < π j-1 , use the two data points close to the target point and the next data point for quadratic Lagrange interpolation:

[0042]

[0043] Obtain the current working condition turbine characteristics.

[0044] Another aspect of the present application, a turbine characteristics calculation system, comprising:

[0045] The numerical reconstruction module is configured to select the maximum expansion ratio π max and the minimum expansion ratio π min on each speed line of the relative corrected speed-expansion ratio characteristic curve of the turbine as the upper and lower limits, respectively, and reconstruct the equal-interval data according to the equal-expansion ratio interval and form a plurality of preliminary β auxiliary lines, wherein each data point in the reconstructed equal-interval data has a serial number (i, j), i represents the characteristic curve number, and j represents the data point number;

[0046] The curve drawing module is configured to connect the data points obtained by reconstruction in the equal-interval data and the corresponding corrected flow and isentropic efficiency according to the same serial number marked in the relative corrected speed-expansion ratio characteristic curve of the turbine, to obtain a plurality of β auxiliary lines.

[0047] The characteristic line interpolation module is configured to collect turbine working condition parameters and convert them into the current working condition relative corrected speed N corAnd the current working condition expansion ratio π, based on the relative conversion speed-expansion ratio characteristic curve with multiple β auxiliary lines, a Lagrange interpolation polynomial with the kth data point number is constructed, the intersection point in the relative conversion speed-expansion ratio characteristic curve of the turbine is searched, the original characteristic curve is grouped according to the size of the relative conversion speed and the curve position of the intersection point, the corresponding group of the turbine is confirmed according to the relative conversion speed of the current working condition, and the current working condition characteristic curve is obtained by using quadratic or cubic Lagrange method for interpolation;

[0048] According to the relative position of the expansion ratio of the current working condition in the relative conversion speed-expansion ratio characteristic curve, an interpolation method other than Lagrange interpolation is used for interpolation to obtain the current working condition characteristic curve and the current working condition β auxiliary line;

[0049] The target interpolation module is configured to interpolate the target point in the current working condition characteristic curve and the current working condition β auxiliary line to obtain the current working condition turbine characteristic.

[0050] The third aspect of the present application provides an electronic device, comprising:

[0051] At least one processor; and

[0052] The memory is in communication connection with the at least one processor; wherein,

[0053] The memory stores instructions executable by the processor, and the instructions are used to be executed by the processor to realize the turbine characteristic calculation method.

[0054] The fourth aspect of the present application provides a computer readable storage medium, the computer readable storage medium stores computer instructions, and the computer instructions are used to be executed by the computer to realize the turbine characteristic calculation method.

[0055] The present application has the following beneficial effects:

[0056] The present application solves the problems of low precision of the existing linear interpolation method, too large calculation amount of the auxiliary line calculation target characteristic, and interpolation error caused by not considering the shape characteristics of the characteristic curve cluster and not performing targeted analysis. BRIEF DESCRIPTION OF DRAWINGS

[0057] Other features, objects and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments made with reference to the accompanying drawings:

[0058] Figure 1 It is a flowchart of a turbine characteristic calculation method in the embodiment of the present application;

[0059] Figure 2is a schematic diagram of the relative corrected speed-expansion ratio characteristic curve of a turbine in an embodiment of the present application;

[0060] Figure 3 is a schematic diagram of a preliminary beta auxiliary line in an embodiment of the present application;

[0061] Figure 4 is a schematic diagram of obtaining multiple beta auxiliary lines in an embodiment of the present application;

[0062] Figure 5 is a schematic diagram of the characteristic curve intersection phenomenon in an embodiment of the present application;

[0063] Figure 6 is a schematic diagram of a current operating condition characteristic line in an embodiment of the present application;

[0064] Figure 7 is a comparison diagram of partial segment quadratic interpolation and full data interpolation effects in an embodiment of the present application. DETAILED DESCRIPTION

[0065] The present application will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the related application, and not to limit the application. In addition, it should be noted that only the parts related to the application are shown in the drawings for ease of description.

[0066] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and embodiments.

[0067] In order to more clearly describe the turbine characteristic calculation method of the present application, the following will be described in combination with Figure 1 The steps in the embodiments of the present application will be described in detail.

[0068] The turbine characteristic calculation method of the first embodiment of the present application includes steps S10-S40, and each step is described in detail as follows:

[0069] This embodiment takes a certain type of turbine driven by high-temperature and high-pressure gas controlled by a solenoid valve as an example to describe the turbine characteristic calculation method suitable for a wide range of operating conditions.

[0070] Step S10, for the relative corrected speed-expansion ratio characteristic curve of the turbine, the maximum expansion ratio π max and the minimum expansion ratio π min are selected as the upper and lower limits on each speed line, and are reconstructed into equidistant data according to the equal expansion ratio interval to form multiple preliminary beta auxiliary lines, wherein each data point in the reconstructed equidistant data has a serial number (i, j), i represents the characteristic curve number, and j represents the data point number;

[0071] The relative equivalent speed-expansion ratio characteristic curve of the turbine is as follows: Figure 2 As shown, some turbine data can be obtained through CFD simulation and bench testing. Subsequent characteristic calculations and other steps are based on the appendix. Figure 2 The original characteristic curves and data expansion are shown. Figure 2 In the figure, the horizontal axis of the turbine characteristic curve represents the expansion ratio π, and the vertical axis represents the equivalent flow rate G. cor And isentropic efficiency η, each curve represents a relative equivalent rotational speed N. cor Turbine characteristics under these conditions.

[0072] Since the original turbine characteristic data is mostly scattered with unequal intervals between data points, it affects subsequent data processing. Therefore, it is necessary to reconstruct the original data.

[0073] Within the expansion ratio range, the number of interval points on each constant-speed expansion ratio characteristic line is the same; connecting the interval points with the same sequence number on each constant-speed expansion ratio characteristic line initially forms the characteristic curve of the β auxiliary line, as shown in the figure. Figure 3 As shown.

[0074] In this embodiment, the process of collecting turbine operating parameters and converting them into a relative equivalent speed N under the current operating conditions is described. cor The expansion ratio π under the current operating conditions is:

[0075]

[0076] Among them, P Tin P represents the turbine inlet pressure. Tout Indicates turbine outlet pressure, N ref T represents the turbine design point speed. ref Indicates the turbine design inlet temperature, N represents, T in It means that T std This indicates that, since the turbine outlet is directly connected to the outside, it is assumed that the turbine outlet pressure is atmospheric pressure (P). Tout =0.101MPa), relative equivalent speed N cor It is a dimensionless quantity.

[0077] Step S20: Connect the reconstructed data points and their corresponding converted flow rates and isentropic efficiencies from the equally spaced data according to the same index marked on the turbine's relative converted speed-expansion ratio characteristic curve to obtain multiple β-auxiliary lines; a schematic diagram of the β-auxiliary lines in the characteristic diagram is shown below. Figure 4 As shown.

[0078] Step S30: Collect turbine operating parameters and convert them into the relative conversion speed N of the current operating condition. corAccording to the relative position of the expansion ratio of the current working condition in the relative position of the relative conversion speed-expansion ratio characteristic curve, an interpolation method other than the Lagrange interpolation is used to interpolate to obtain the current working condition characteristic curve and the current working condition β auxiliary line.

[0079] According to the relative position of the expansion ratio of the current working condition in the relative position of the relative position of the relative conversion speed-expansion ratio characteristic curve, an interpolation method other than the Lagrange interpolation is used to interpolate to obtain the current working condition characteristic curve and the current working condition β auxiliary line.

[0080] In the embodiment, the Lagrange interpolation polynomial L k (π) is:

[0081]

[0082] Wherein, π represents the current working condition expansion ratio, π k represents the current working condition expansion ratio of the kth point, π k+1 represents the current working condition expansion ratio of the k+1th point, π k-1 represents the current working condition expansion ratio of the k-1th point, π m represents the current working condition expansion ratio of the mth data point, and m represents that each β auxiliary line has m data points participating in interpolation calculation.

[0083] According to the auxiliary line generation diagram as Figure 3 shown, the two curves with the maximum and minimum expansion ratio in the auxiliary line formed by the known data are interpolated using the Lagrange interpolation, with the relative conversion speed as the horizontal coordinate, to obtain the upper and lower limits of the expansion ratio corresponding to the target working condition, and divide them into j parts, and the j points formed by the vertical coordinates are the required expansion ratio π j .

[0084] In the original characteristic diagram, interpolation calculation is performed along the existing j β auxiliary lines, and the horizontal coordinates of the interpolation points are the intersection expansion ratio values obtained in the previous step. Connecting the calculated interpolation points, the target speed characteristic line formed by the j interpolation points can be obtained.

[0085] The target speed characteristic line formed by the j interpolation points can be obtained by connecting the calculated interpolation points. Figure 5Taking the partial original characteristic curves shown as an example, some characteristic curves intersect, and the β-auxiliary line shows a significant inflection point at the intersection. If the relative equivalent speed under the current operating condition is within the range of the existing characteristic curves, there will be no significant interpolation error due to the dense data; however, when the current operating condition is outside the range of the existing characteristic curves, using the complete β-auxiliary line for interpolation calculation will result in a large error. To avoid the error caused by the intersection of the original characteristic curves in the interpolation fitting, β-auxiliary lines are selected and Lagrange interpolation calculations are performed according to the region to which the target characteristic point belongs.

[0086] In this embodiment, the method for obtaining the current operating condition characteristic curve and the current operating condition β auxiliary line is as follows:

[0087] N cor The region < N1 is designated as the low-speed region, and N1≤N cor ≤N n The area is divided into the middle area and N. cor >N n The area was designated as a high-speed zone, and different parameters were used for Lagrange interpolation calculations.

[0088] Based on the Lagrange interpolation polynomial L at the k-th point k (π), calculate the converted flow rate G corresponding to the interpolation coordinate point of the j-th β auxiliary line. cor,j The isentropic efficiency η corresponding to the interpolation coordinate points j :

[0089]

[0090] Where, π j η represents the current expansion ratio at point j. k This represents the isentropic efficiency corresponding to the k-th point;

[0091] Determine the intersection points between the original characteristic curves and the two intersecting original characteristic curves N. a and N b (a < b);

[0092] Based on the relative conversion speed N under the current operating conditions cor The region enclosed by the original characteristic curve (N1~N) n Interpolation is performed on the relationship between ), specifically as follows:

[0093] If the relative conversion speed N under the current operating conditions cor The region smaller than the area enclosed by the original characteristic curve, i.e., N cor When <N1, N1 represents the relative equivalent speed corresponding to the first original characteristic curve, N n This represents the relative equivalent speed corresponding to the last original characteristic curve. Each β auxiliary line has m = a data points participating in the interpolation calculation, selected from N1 to N...a The Lagrange interpolation is calculated for a line a β auxiliary line between the two points:

[0094]

[0095] If the relative converted speed N of the current working condition cor is within the area surrounded by the original characteristic curve, i.e. N1≤N cor ≤N n , the interpolation is calculated for m=n data points of each β auxiliary line, and the Lagrange interpolation is calculated for all β auxiliary lines:

[0096]

[0097] If the relative converted speed N of the current working condition cor is greater than the area surrounded by the original characteristic curve, i.e. N cor >N n , the Lagrange interpolation is calculated for n-b+1 β auxiliary lines between N b and N n :

[0098]

[0099] The current working condition characteristic curve and the current working condition β auxiliary line are obtained after the Lagrange interpolation. The current working condition characteristic curve is shown in FIG. 3. Figure 6

[0100] In step S40, the target point in the current working condition characteristic curve and the current working condition β auxiliary line is interpolated to obtain the current working condition turbine characteristic.

[0101] In the embodiment, the target point in the current working condition characteristic curve and the current working condition β auxiliary line is interpolated once to obtain the current working condition turbine characteristic, specifically:

[0102] The target point is selected in the current working condition characteristic curve, the expansion ratio π corresponding to the target point is taken as the interpolation point abscissa, and the data points on the current working condition characteristic curve corresponding to the interpolation point abscissa are expressed as πi, i=1, 2, …, j according to the expansion ratio from small to large: i

[0103] According to the relationship between the interpolation point abscissa and the current working condition characteristic curve, the quadratic Lagrange interpolation is performed respectively;

[0104] When π≤π1or π≥π j , i.e. the expansion ratio corresponding to the target point is outside the current working condition characteristic curve, the linear Lagrange interpolation is performed using the two data points at the endpoints:

[0105] ​​

[0106]

[0107] When π1< π ≤ π2or π j-1 ≤ π < π j , use three data points near the end point to perform quadratic Lagrange interpolation:

[0108] The quadratic Lagrange interpolation when π1< π ≤ π2is:

[0109]

[0110] The quadratic Lagrange interpolation when π j-1 ≤ π < π j is:

[0111]

[0112] When π2< π < π j-1 , use the two data points before and the one data point after the target point horizontal coordinate to perform quadratic Lagrange interpolation:

[0113]

[0114] Obtain the current working condition turbine characteristic.

[0115] The turbine characteristic calculation using the method has obvious advantages relative to other methods that do not distinguish characteristic ranges and use all data points to perform interpolation calculation. The characteristic curve formed by the method and the conventional method is shown in the attached appendix Figure 7 . The method avoids the Runge phenomenon at the end, and relative to cubic spline interpolation, reduces the order and number of the interpolation polynomials, and significantly reduces the calculation amount.

[0116] Although the above embodiments describe the steps in the above order, those skilled in the art can understand that, in order to achieve the effects of the embodiments, the different steps do not have to be executed in such an order, and they can be executed simultaneously (in parallel) or in a reversed order, and these simple changes are within the protection scope of the present application.

[0117] The turbine characteristic calculation system of the second embodiment of the present application comprises:

[0118] The numerical reconstruction module is configured to select the maximum expansion ratio π max and the minimum expansion ratio π minThe equal-interval data is reconstructed according to the equal-expansion-ratio intervals to form a plurality of preliminary beta auxiliary lines as upper and lower limits, wherein each data point in the reconstructed equal-interval data has a serial number (i, j), i represents a characteristic curve number, and j represents a data point number;

[0119] The curve drawing module is configured to connect the data points obtained by reconstruction in the equal-interval data and corresponding converted flow and equal-entropy efficiency according to the same serial number marked in the relative converted speed-expansion ratio characteristic curve of the turbine, to obtain a plurality of beta auxiliary lines.

[0120] The characteristic line interpolation module is configured to collect turbine working condition parameters and convert them into a current working condition relative converted speed N cor and a current working condition expansion ratio π, construct a Lagrange interpolation polynomial of the kth data point based on the relative converted speed-expansion ratio characteristic curve with a plurality of beta auxiliary lines, search for a cross point in the relative converted speed-expansion ratio characteristic curve of the turbine, group the original characteristic curves according to the size of the relative converted speed and the curve position of the cross point, confirm the corresponding group of the turbine according to the current working condition relative converted speed, use a quadratic or cubic Lagrange method for interpolation, and obtain a current working condition characteristic curve and a current working condition beta auxiliary line.

[0121] The target interpolation module is configured to interpolate target points in the current working condition characteristic curve and the current working condition beta auxiliary line, to obtain a current working condition turbine characteristic.

[0122] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process and related description of the system described above can refer to the corresponding process in the foregoing method embodiments, which will not be described here.

[0123] It should be noted that the turbine characteristic calculation system provided in the above embodiments is only exemplified by the division of the above functional modules, and in actual application, the above functions can be completed by different functional modules according to needs, that is, the modules or steps in the embodiments of the present application are further decomposed or combined, for example, the modules in the above embodiments can be combined into one module, or can be further split into multiple sub-modules to complete all or part of the functions described above. The names of the modules and steps involved in the embodiments of the present application are only for distinguishing the modules and steps, and should not be considered as an improper limitation of the present application.

[0124] The third embodiment of the electronic device provided by the present application comprises:

[0125] at least one processor; and

[0126] a memory in communication connection with the at least one processor; wherein

[0127] The memory stores instructions executable by the processor for execution by the processor to implement the turbine characteristic calculation method described above.

[0128] A computer readable storage medium of a fourth embodiment of the application stores computer instructions for execution by the computer to implement the turbine characteristic calculation method described above.

[0129] Those skilled in the art can clearly understand that, for the convenience and brevity of the description, the specific working processes of the storage device and the processing device described above and the related descriptions can refer to the corresponding processes in the foregoing method embodiments, which will not be described here.

[0130] Those skilled in the art should be aware that the modules, method steps of each example described in connection with the embodiments disclosed herein can be implemented by electronic hardware, computer software or a combination of the two. The programs corresponding to the software modules and method steps can be placed in a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. In order to clearly illustrate the interchangeability of electronic hardware and software, the components and steps of each example have been generally described in the foregoing description. Whether the functions are performed by electronic hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0131] The terms "first", "second", and the like are used to distinguish similar objects, rather than to describe or indicate a particular order or sequence.

[0132] The term "comprising" or any other similar term is intended to encompass non-exclusive inclusion, so that a process, method, article or device / apparatus including a series of elements includes not only those elements, but also other elements not explicitly listed, or inherent to the process, method, article or device / apparatus.

[0133] So far, the technical solution of the application has been described in combination with the preferred embodiments shown in the drawings, but those skilled in the art can easily understand that the protection scope of the application is obviously not limited to these specific embodiments. Those skilled in the art can make equivalent changes or replacements to the related technical features without departing from the principles of the application, and the technical solutions after the changes or replacements will fall within the protection scope of the application.

Claims

1. A method of calculating a turbine characteristic, characterized by, The method comprises: The maximum expansion ratio π max and the minimum expansion ratio π min on each speed line of the relative converted speed-expansion ratio characteristic curve of the turbine are selected as upper and lower limits respectively, and are reconstructed into equidistant data according to equal expansion ratio intervals to form a plurality of preliminary β auxiliary lines, wherein each data point of the reconstructed equidistant data has a serial number (i, j), i represents the characteristic curve number, and j represents the data point number; connecting the data points obtained by reconstruction in the equidistant data and corresponding converted flow and isentropic efficiency according to the same serial number marked in the relative converted speed-expansion ratio characteristic curve of the turbine to obtain multiple beta auxiliary lines; Collecting turbine working condition parameters and converting into current working condition relative conversion speed N cor And current working condition expansion ratio π, based on the relative conversion speed-expansion ratio characteristic curve with multiple β auxiliary lines, constructing the Lagrange interpolation polynomial with the data point number being the kth, searching the intersection point in the relative conversion speed-expansion ratio characteristic curve of the turbine, grouping the original characteristic curve according to the size of the relative conversion speed and the curve position where the intersection point is located, confirming the corresponding group of the turbine according to the current working condition relative conversion speed, using the quadratic or cubic Lagrange method for interpolation, and obtaining the current working condition characteristic curve. using an interpolation method other than Lagrange interpolation to perform interpolation according to the relative position of the expansion ratio of the current working condition in the relative converted speed-expansion ratio characteristic curve to obtain a current working condition characteristic curve and a current working condition beta auxiliary line; performing interpolation on the target points in the current working condition characteristic curve and the current working condition beta auxiliary line to obtain a current working condition turbine characteristic.

2. The method of claim 1, wherein The turbine working condition parameters are collected and converted into the current working condition relative conversion speed N cor And the current working condition expansion ratio π is: where P Tin represents the turbine inlet pressure, P Tout represents the turbine exit pressure, N ref represents the turbine design point speed, T ref represents the turbine design inlet temperature, N represents the turbine actual speed, T in represents the turbine inlet temperature, T std = 288.15 K, represents the standard temperature.

3. The method of claim 2, wherein The number of the configuration data points is the Lagrange interpolation polynomial L of the kth k (π) is: wherein, π denotes the current operating condition expansion ratio, π k denotes the current operating condition expansion ratio of the kth point, π k+1 denotes the current operating condition expansion ratio of the k+1th point, π k-1 denotes the current operating condition expansion ratio of the k-1th point, π m denotes the current operating condition expansion ratio of the mth data point, m denotes that there are m data points participating in the interpolation calculation for each β auxiliary line.

4. The method of claim 3, wherein The method for obtaining the current working condition characteristic curve and the current working condition beta auxiliary line comprises: Lagrange interpolation polynomial L based on the data points numbered k k (π), to calculate the conversion flow G corresponding to the interpolation coordinate point of the jth β auxiliary line cor,j and the isentropic efficiency η corresponding to the interpolation coordinate point j : wherein, π j represents the current operating expansion ratio of the jth point, η k represents the isentropic efficiency corresponding to the kth point; determining a crossing point between the original characteristic curves and the two original characteristic curves N crossing at the crossing point a and N b (a < b); According to the relative conversion speed N of the current working condition cor The relationship between the area (N1~N n ) surrounded by the original characteristic curve and the target characteristic curve is interpolated, specifically: If the relative converted speed N cor of the current working condition is less than the area surrounded by the original characteristic curves, i.e. N cor <N1, N1 represents the relative converted speed corresponding to the first original characteristic curve, and N n represents the relative converted speed corresponding to the last original characteristic curve, a Lagrange interpolation calculation is performed on a = a number of β auxiliary lines between N1 and N a ​ If the relative converted speed N cor of the current working condition is within the region surrounded by the original characteristic curve, i.e. N cor ≤N n , with m = n data points participating in the interpolation calculation for each β auxiliary line, all β auxiliary lines are selected for Lagrange interpolation calculation: If the relative converted speed N cor of the current working condition is greater than the area surrounded by the original characteristic curve, i.e. N cor > N n , n-b+1 β auxiliary lines between N b and N n are selected to perform Lagrange interpolation calculation. obtaining the current working condition characteristic curve and the current working condition beta auxiliary line after performing Lagrange interpolation.

5. The method of claim 4, wherein The method for obtaining the current working condition turbine characteristic by performing one-time interpolation on the target points in the current working condition characteristic curve and the current working condition beta auxiliary line comprises: In the current operating characteristic curve, a target point is selected, the expansion ratio π corresponding to the target point is taken as an interpolation point abscissa, and data points on the current operating characteristic curve corresponding to the interpolation point abscissa are expressed as π in ascending order of expansion ratio i , i = 1, 2, …, j: performing secondary Lagrange interpolation according to the relationship between the interpolation point abscissa and the current working condition characteristic curve; When π≤π1or π≥π j When the expansion ratio corresponding to the target point is outside the current operating characteristic curve, linear Lagrange interpolation is performed using the two data points of the end points. When π1< π ≤ π2or π j-1 ≤ π < π j When π1< π ≤ π2or π j-1 ≤ π < π j When π1< π ≤ π2or π j-1 ≤ π < π j When π1< π ≤ π2or π j-1 ≤ π < π the secondary Lagrange interpolation when π1 < π ≤ π2 is: When π j-1 ≤ π < π j The quadratic Lagrange interpolation for when π When π2< π < π j-1 When π2< π < π j-1 When π2< π < π j-1 When π2< π < π j-1 When π2< π < π j-1 When π2< π < π j-1 When π2< π < π j-1 obtaining the current working condition turbine characteristic.

6. A turbine characteristic calculation system characterized by comprising: The method comprises: The numerical reconstruction module is configured to select the maximum expansion ratio π max and the minimum expansion ratio π min of each speed line of the relative corrected speed-expansion ratio characteristic curve of the turbine as the upper and lower limits respectively, reconstruct the equal-interval data according to the equal-expansion ratio interval, and form a plurality of preliminary β auxiliary lines, wherein each data point of the reconstructed equal-interval data has a serial number (i, j), i represents the characteristic curve number, and j represents the data point number. a curve drawing module configured to connect the data points obtained by reconstruction in the equidistant data and corresponding converted flow and isentropic efficiency according to the same serial number marked in the relative converted speed-expansion ratio characteristic curve of the turbine to obtain multiple beta auxiliary lines; The characteristic line interpolation module is configured to collect turbine working condition parameters and convert them into a current working condition relative conversion speed N cor and a current working condition expansion ratio π, based on a relative conversion speed-expansion ratio characteristic curve with multiple β auxiliary lines, a Lagrange interpolation polynomial of the kth data point is constructed, a cross point in the relative conversion speed-expansion ratio characteristic curve of the turbine is searched, the original characteristic curve is grouped according to the size of the relative conversion speed and the position of the cross point on the curve, the corresponding group of the turbine is confirmed according to the current working condition relative conversion speed, interpolation is performed using a quadratic or cubic Lagrange method, and a current working condition characteristic curve and a current working condition β auxiliary line are obtained. using an interpolation method other than Lagrange interpolation to perform interpolation according to the relative position of the expansion ratio of the current working condition in the relative converted speed-expansion ratio characteristic curve to obtain a current working condition characteristic curve and a current working condition beta auxiliary line; a target interpolation module configured to perform interpolation on the target points in the current working condition characteristic curve and the current working condition beta auxiliary line to obtain a current working condition turbine characteristic. 7.An electronic device comprising: at least one processor; and a memory communicatively connected with the at least one processor; wherein the memory stores instructions executable by the processor, and the instructions are used to be executed by the processor to implement the turbine characteristic calculation method according to any one of claims 1 to 5. 8.A computer readable storage medium storing computer instructions, and the computer instructions are used to be executed by the computer to implement the turbine characteristic calculation method according to any one of claims 1 to 5.

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