A method and related equipment for detecting the peak-to-peak value of pressure pulsation of a hydropower station unit under transient conditions

Abstract

The present disclosure provides a method and related equipment for detecting the peak-to-peak value of pressure pulsation in a hydropower station unit under transient operating conditions. The method comprises: obtaining a pressure pulsation signal at a preset location in the hydropower station unit; decomposing the pressure pulsation signal to obtain a corresponding trend item signal and a pulsation item signal; performing signal mapping processing on the trend item signal and the pulsation item signal to obtain the peak-to-peak value of the pulsation item at different cycle lengths; and calculating the average of the peak-to-peak values ​​of the pulsation item at different cycle lengths to obtain the peak-to-peak value of the pressure pulsation at the preset location.

Description

Technical Field

[0001] The present disclosure relates to the field of pressure analysis, and in particular to a method and related equipment for detecting peak-to-peak pressure pulsation of a hydropower station unit under transient operating conditions. Background Art

[0002] During transient operating conditions at hydropower stations, the volute pressure rise and the tailwater pressure drop are unstable, which can easily lead to safety issues. However, existing methods for detecting peak pressure under transient conditions have low accuracy and long analysis times, making them inadequate for practical applications. Summary of the Invention

[0003] The present disclosure proposes a method and related equipment for detecting the peak-to-peak value of pressure pulsation of a hydropower station unit under transient operating conditions, so as to solve, to a certain extent, the technical problems of low accuracy in pressure peak detection and long analysis time under transient operating conditions of the hydropower station unit.

[0004] In a first aspect, the present disclosure provides a method for detecting the peak-to-peak value of pressure pulsation of a hydropower station unit under transient operating conditions, comprising:

[0005] Obtaining a pressure pulsation signal at a preset position in a unit of the hydropower station;

[0006] Decomposing the pressure pulsation signal to obtain corresponding trend term signal and pulsation term signal;

[0007] Performing signal mapping processing on the trend item signal and the pulsation item signal to obtain peak-to-peak values ​​of the pulsation item at different cycle lengths;

[0008] The average value of the peak-to-peak value of the pulsation item at different cycle lengths is calculated to obtain the peak-to-peak value of the pressure pulsation at the preset position.

[0009] In some embodiments, decomposing the pressure pulsation signal to obtain corresponding trend item signals and pulsation item signals includes:

[0010] Decomposing the pressure pulsation signal into a plurality of intrinsic mode function components;

[0011] Convolution and local feature extraction are performed on each of the intrinsic mode function components to obtain the trend item signal and the pulsation item signal.

[0012] In some embodiments, performing convolution and local feature extraction on each of the intrinsic mode function components to obtain the trend term signal and the pulsation term signal includes:

[0013] Extracting a low-frequency portion of the intrinsic mode function component to obtain the trend term signal;

[0014] The high-frequency part of the intrinsic mode function component is extracted to obtain the pulsating term signal.

[0015] In some embodiments, performing signal mapping processing on the trend item signal and the pulsation item signal to obtain peak-to-peak values ​​of the pulsation item at different cycle lengths includes:

[0016] Determining a first time node corresponding to a maximum eigenvalue and a second time node corresponding to a minimum eigenvalue in the trend item;

[0017] Determine at least one cycle length based on the first time node and / or the second time node;

[0018] For each cycle length, the peak-to-peak value of the pulsation term is obtained based on the difference between the maximum and minimum times of the pulsation term within the cycle length.

[0019] In some embodiments, determining a first time node corresponding to a maximum eigenvalue and a second time node corresponding to a minimum eigenvalue in the trend item includes:

[0020] Obtaining the first time node based on the time node in the trend item time linked list pointed to by the first pointer of the maximum eigenvalue;

[0021] The second time node is obtained based on the time node in the trend item time linked list pointed to by the second pointer of the minimum eigenvalue.

[0022] In some embodiments, calculating the average of the peak-to-peak values ​​of the pulsation terms at different cycle lengths comprises:

[0023] Wherein, A is the average value, n is the number of different cycle lengths, and k is the sequence number of the cycle length.

[0024] In some embodiments, calculating the average of the peak-to-peak values ​​of the pulsation terms at different cycle lengths further includes:

[0025] Calculating the confidence level of the peak-to-peak value of the pulsation term corresponding to each cycle length;

[0026] The average value is calculated based on the peak-to-peak value of the pulsation item corresponding to the confidence level being greater than or equal to the confidence level threshold.

[0027] In a second aspect of the present disclosure, a device for detecting peak-to-peak pressure pulsation of a hydropower station unit under transient operating conditions is provided, comprising:

[0028] An acquisition module, configured to acquire a pressure pulsation signal at a preset position in a unit of the hydropower station;

[0029] a decomposition module, configured to decompose the pressure pulsation signal to obtain corresponding trend item signals and pulsation item signals;

[0030] A mapping module, configured to perform signal mapping processing on the trend item signal and the pulsation item signal to obtain peak-to-peak values ​​of the pulsation item at different cycle lengths;

[0031] The averaging module is used to calculate the average value of the peak-to-peak value of the pulsation item under different cycle lengths to obtain the peak-to-peak value of the pressure pulsation at the preset position.

[0032] In some embodiments, decomposing the pressure pulsation signal to obtain corresponding trend item signals and pulsation item signals includes:

[0033] Decomposing the pressure pulsation signal into a plurality of intrinsic mode function components;

[0034] Convolution and local feature extraction are performed on each of the intrinsic mode function components to obtain the trend item signal and the pulsation item signal.

[0035] In some embodiments, performing convolution and local feature extraction on each of the intrinsic mode function components to obtain the trend term signal and the pulsation term signal includes:

[0036] Extracting a low-frequency portion of the intrinsic mode function component to obtain the trend term signal;

[0037] The high-frequency part of the intrinsic mode function component is extracted to obtain the pulsating term signal.

[0038] In some embodiments, performing signal mapping processing on the trend item signal and the pulsation item signal to obtain peak-to-peak values ​​of the pulsation item at different cycle lengths includes:

[0039] Determining a first time node corresponding to a maximum eigenvalue and a second time node corresponding to a minimum eigenvalue in the trend item;

[0040] Determine at least one cycle length based on the first time node and / or the second time node;

[0041] For each cycle length, the peak-to-peak value of the pulsation term is obtained based on the difference between the maximum and minimum times of the pulsation term within the cycle length.

[0042] In some embodiments, determining a first time node corresponding to a maximum eigenvalue and a second time node corresponding to a minimum eigenvalue in the trend item includes:

[0043] Obtaining the first time node based on the time node in the trend item time linked list pointed to by the first pointer of the maximum eigenvalue;

[0044] The second time node is obtained based on the time node in the trend item time linked list pointed to by the second pointer of the minimum eigenvalue.

[0045] In some embodiments, calculating the average of the peak-to-peak values ​​of the pulsation terms at different cycle lengths comprises:

[0046] Wherein, A is the average value, n is the number of different cycle lengths, and k is the sequence number of the cycle length.

[0047] In some embodiments, calculating the average of the peak-to-peak values ​​of the pulsation terms at different cycle lengths further includes:

[0048] Calculating the confidence level of the peak-to-peak value of the pulsation term corresponding to each cycle length;

[0049] The average value is calculated based on the peak-to-peak value of the pulsation item corresponding to the confidence level being greater than or equal to the confidence level threshold.

[0050] In a third aspect of the present disclosure, an electronic device is provided, comprising one or more processors, a memory; and one or more programs, wherein the one or more programs are stored in the memory and executed by the one or more processors, and the programs include instructions for executing the method described in the first aspect.

[0051] According to a fourth aspect of the present disclosure, a non-volatile computer-readable storage medium containing a computer program is provided. When the computer program is executed by one or more processors, the processors are caused to execute the method described in the first aspect.

[0052] In a fifth aspect of the present disclosure, a computer program product is provided, comprising computer program instructions, which, when executed on a computer, enable the computer to execute the method described in the first aspect.

[0053] As can be seen from the foregoing, the present disclosure provides a method and related equipment for detecting peak-to-peak pressure pulsation of a hydropower station unit under transient operating conditions. By employing variational modal decomposition (VMD) technology to decompose the pressure signal at the target location of the hydropower station unit, the method yields trend and pulsation terms. Signal mapping is then used to calculate the peak-to-peak value of the pulsation term at different cycle lengths, thereby determining the peak-to-peak value of the pressure pulsation. This method improves the accuracy of peak-to-peak pressure pulsation measurements under transient conditions, providing reasonable and accurate technical support for relevant pressure data analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the technical solutions in the present disclosure or related technologies, the following briefly introduces the drawings required for use in the embodiments or related technical descriptions. Obviously, the drawings described below are only embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0055] Figure 1 Schematic diagram of a detection architecture for peak-to-peak pressure pulsation of a hydropower station unit under transient conditions according to an embodiment of the present disclosure.

[0056] Figure 2 Schematic diagram of the hardware structure of an exemplary electronic device according to an embodiment of the present disclosure.

[0057] Figure 3 Schematic diagram of a flow chart of a method for detecting peak-to-peak pressure pulsation of a hydropower station unit under transient conditions according to an embodiment of the present disclosure.

[0058] Figure 4 Schematic diagram of a method for detecting the peak-to-peak value of pressure pulsation of a hydropower station unit under transient conditions according to an embodiment of the present disclosure.

[0059] Figure 5 Schematic diagram of a device for detecting peak-to-peak pressure pulsation of a hydropower station unit under transient conditions according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0060] In order to make the objectives, technical solutions and advantages of the present disclosure more clearly understood, the present disclosure is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0061] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present disclosure should have the usual meanings understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the embodiments of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative position relationships. When the absolute position of the described object changes, the relative position relationship may also change accordingly.

[0062] It is understandable that before using the technical solutions disclosed in the various embodiments of this disclosure, the type, scope of use, usage scenarios, etc. of the personal information involved in this disclosure should be informed to the user and the user's authorization should be obtained in an appropriate manner in accordance with relevant laws and regulations.

[0063] For example, in response to a user's active request, a prompt message is sent to the user to clearly inform the user that the operation requested will require the acquisition and use of the user's personal information. This allows the user to independently choose whether to provide personal information to the electronic device, application, server, storage medium, or other software or hardware that performs the operations of the disclosed technical solution based on the prompt message.

[0064] It is understandable that the above notification and user authorization process are merely illustrative and do not limit the implementation of the present disclosure. Other methods that comply with relevant laws and regulations may also be applied to the implementation of the present disclosure.

[0065] Figure 1 A schematic diagram of a detection architecture for the peak-to-peak pressure pulsation of a hydropower station unit under transient conditions according to an embodiment of the present disclosure is shown. Figure 1 The detection architecture 100 for the peak-to-peak pressure pulsation of a hydropower station unit under transient conditions may include a server 110, a terminal 120, and a network 130 providing a communication link. The server 110 and the terminal 120 may be connected via a wired or wireless network 130. The server 110 may be an independent physical server, a server cluster or distributed system consisting of multiple physical servers, or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, security services, and CDN.

[0066] Terminal 120 can be implemented in hardware or software. For example, when implemented in hardware, terminal 120 can be any electronic device with a display screen that supports page display, including but not limited to smartphones, tablet computers, e-book readers, laptop computers, and desktop computers. When terminal 120 is implemented in software, it can be installed in the electronic devices listed above; it can be implemented as multiple software or software modules (such as software or software modules used to provide distributed services), or it can be implemented as a single software or software module, and no specific limitations are given here.

[0067] It should be noted that the method for detecting the peak-to-peak value of pressure pulsation of a hydropower station unit under transient conditions provided in the embodiment of the present application can be executed by the terminal 120 or by the server 110. It should be understood that Figure 1The number of terminals, networks, and servers in the embodiment is for illustration only and is not intended to limit the number of terminals, networks, and servers.

[0068] Figure 2 FIG. 2 shows a schematic diagram of the hardware structure of an exemplary electronic device 200 provided in an embodiment of the present disclosure. Figure 2 As shown, electronic device 200 may include: processor 202, memory 204, network module 206, peripheral interface 208 and bus 210. Processor 202, memory 204, network module 206 and peripheral interface 208 are connected to each other through bus 210 in communication with each other within electronic device 200.

[0069] The processor 202 may be a central processing unit (CPU), a detector for peak-to-peak pressure pulsation of a hydropower station unit under transient conditions, a neural network processor (NPU), a microcontroller (MCU), a programmable logic device, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), or one or more integrated circuits. The processor 202 may be used to perform functions related to the technology described in this disclosure. In some embodiments, the processor 202 may also include multiple processors integrated into a single logical component. For example, Figure 2 As shown, the processor 202 may include a plurality of processors 202a, 202b, and 202c.

[0070] The memory 204 may be configured to store data (eg, instructions, computer code, etc.). Figure 2 As shown, the data stored in the memory 204 may include program instructions (for example, program instructions for implementing the method for detecting the peak-to-peak value of the pressure pulsation of the hydropower station unit under transient conditions according to an embodiment of the present disclosure) and data to be processed (for example, the memory may store configuration files of other modules, etc.). The processor 202 may also access the program instructions and data stored in the memory 204, and execute the program instructions to operate on the data to be processed. The memory 204 may include a volatile storage device or a non-volatile storage device. In some embodiments, the memory 204 may include a random access memory (RAM), a read-only memory (ROM), an optical disk, a magnetic disk, a hard disk, a solid-state drive (SSD), a flash memory, a memory stick, etc.

[0071] The network module 206 can be configured to provide the electronic device 200 with communication with other external devices via a network. The network can be any wired or wireless network capable of transmitting and receiving data. For example, the network can be a wired network, a local wireless network (e.g., Bluetooth, WiFi, near field communication (NFC)), a cellular network, the Internet, or a combination thereof. It will be appreciated that the type of network is not limited to the specific examples above. In some embodiments, the network module 306 can include any number of network interface controllers (NICs), radio frequency modules, transceivers, modems, routers, gateways, adapters, cellular network chips, and the like.

[0072] The peripheral interface 208 can be configured to connect the electronic device 200 to one or more peripheral devices to implement information input and output. For example, the peripheral devices can include input devices such as a keyboard, a mouse, a touchpad, a touch screen, a microphone, and various sensors, and output devices such as a display, a speaker, a vibrator, and an indicator light.

[0073] The bus 210 can be configured to transmit information between the various components of the electronic device 200 (e.g., the processor 202, the memory 204, the network module 206, and the peripheral interface 208), such as an internal bus (e.g., a processor-memory bus), an external bus (USB port, PCI-E bus), etc.

[0074] It should be noted that although the architecture of the electronic device 200 shown above only shows the processor 202, the memory 204, the network module 206, the peripheral interface 208, and the bus 210, in a specific implementation, the architecture of the electronic device 200 may also include other components necessary for normal execution. In addition, it will be understood by those skilled in the art that the architecture of the electronic device 200 may also include only the components necessary to implement the embodiments of the present disclosure, and does not necessarily include all the components shown in the figure.

[0075] Under transient operating conditions of the unit, the rise in volute pressure and the drop in tailwater pipe pressure are unstable, posing safety issues. The peak-to-peak value of pressure pulsation is the most direct reflection of whether the pressure at the measuring point is stable. Under steady-state conditions, when the analysis duration meets certain conditions, the peak-to-peak size is approximately independent of the duration; under transient conditions, the analysis duration is long, and the peak-to-peak value cannot accurately reflect the pressure variation pattern, while the analysis duration is short, and the peak-to-peak value is meaningless or unstable. Therefore, it is necessary to process the peak-to-peak value analysis of pressure pulsation under transient conditions to obtain a more accurate peak-to-peak value of pressure pulsation. Therefore, how to reduce the detection error of the peak-to-peak value of pressure pulsation under transient conditions and improve detection efficiency has become a technical problem that needs to be solved urgently.

[0076] In light of this, embodiments of the present disclosure provide a method and related equipment for detecting the peak-to-peak value of pressure pulsation at a hydropower station unit under transient conditions. By employing variational modal decomposition (VMD) technology to decompose the pressure signal at the target location of the hydropower station unit, trend terms and pulsation terms are obtained. Signal mapping is then used to calculate the peak-to-peak value of the pulsation term at different cycle lengths, thereby determining the peak-to-peak value of pressure pulsation. This method improves the accuracy of peak-to-peak pressure pulsation measurements under transient conditions, providing reasonable and accurate technical support for relevant pressure data analysis.

[0077] See also Figure 3 , Figure 3 A schematic flow chart of a method for detecting the peak-to-peak value of pressure pulsation of a hydropower station unit under transient conditions according to an embodiment of the present disclosure is shown. The method for detecting the peak-to-peak value of pressure pulsation of a hydropower station unit under transient conditions according to an embodiment of the present disclosure can be deployed on a server or client side. Figure 3 In the method 300 for detecting the peak-to-peak value of pressure pulsation of a hydropower station unit under transient conditions, the method 300 may further include the following steps.

[0078] In step S310, a pressure pulsation signal at a preset position in the hydropower station unit is obtained.

[0079] Among them, the preset position can refer to a specific position in the hydropower station unit that is pre-set according to the design and monitoring requirements and is equipped with a sensor. These positions are usually selected in places that can reflect key information about the operating status of the unit, such as the volute inlet, the tailwater pipe outlet, the periphery of the guide vane, etc., because these areas are easily affected by the hydrodynamic effects. The pressure pulsation signal can refer to the pressure fluctuations generated inside the pipe or specific structural parts due to factors such as the non-uniformity of the water flow, eddy currents, cavitation, etc. when the water flows through the volute, the water guide mechanism, the impeller, etc. during the operation of the hydropower station. This pressure fluctuation that changes rapidly over time is called a pressure pulsation signal, which contains rich information about the operating status of the unit. Sensors can be set at preset positions to sense physical quantities (such as pressure) and convert them into electrical signals. For example, piezoresistive and piezoelectric pressure sensors can monitor pressure changes in real time and convert pressure values ​​into electrical signals for analysis.

[0080] In step S320, the pressure pulsation signal is decomposed to obtain corresponding trend item signals and pulsation item signals.

[0081] Among them, VMD technology can be applied to the collected pressure pulsation signals respectively. VMD decomposes the signal into a series of physically meaningful intrinsic mode functions (IMFs) through an iterative optimization process. Each IMF represents a specific frequency component of the signal, including a trend term (low-frequency component) and a pulsation term (high-frequency component). Specifically, the volute inlet pressure pulsation signal and the tailwater pipe inlet pressure pulsation signal under transient conditions can be collected by sensors. The original pressure pulsation signal is decomposed into multiple IMF components using variational mode decomposition technology for the volute inlet pressure pulsation signal and the tailwater pipe inlet pressure pulsation signal under transient conditions, and each IMF component is convolved to extract local features to obtain the trend term signal and pulsation term signal of the pressure pulsation signal.

[0082] In some embodiments, decomposing the pressure pulsation signal to obtain corresponding trend item signals and pulsation item signals includes:

[0083] Decomposing the pressure pulsation signal into a plurality of intrinsic mode function components;

[0084] Convolution and local feature extraction are performed on each of the intrinsic mode function components to obtain the trend item signal and the pulsation item signal.

[0085] In some embodiments, performing convolution and local feature extraction on each of the intrinsic mode function components to obtain the trend term signal and the pulsation term signal includes:

[0086] Extracting a low-frequency portion of the intrinsic mode function component to obtain the trend term signal;

[0087] The high-frequency part of the intrinsic mode function component is extracted to obtain the pulsating term signal.

[0088] Convolution is performed on each IMF component to extract local signal features, enhance the ability to identify signal details, and facilitate subsequent feature analysis. Based on the convolution results, trend and pulsation terms are separated. The trend term reflects the long-term trend of the signal, while the pulsation term reflects the instantaneous fluctuation characteristics of the signal.

[0089] In step S330, signal mapping processing is performed on the trend item signal and the pulsation item signal to obtain the peak-to-peak value of the pulsation item under different cycle lengths.

[0090] The signal mapping process calculates the time points corresponding to the maximum and minimum eigenvalues ​​in the trend term. This helps understand the overall trend of the signal. The pulsation term is periodically analyzed, calculating the peak-to-peak value (i.e., the difference between the maximum and minimum values ​​of the signal) at different periods. A weighted average method (0.2k + 0.8 in the formula) is used to comprehensively consider the importance of different periods, where k is the period number and n is the total number of periods. This step aims to extract the typical fluctuation amplitude of the pulsation term.

[0091] In some embodiments, performing signal mapping processing on the trend item signal and the pulsation item signal to obtain peak-to-peak values ​​of the pulsation item at different cycle lengths includes:

[0092] Determining a first time node corresponding to a maximum eigenvalue and a second time node corresponding to a minimum eigenvalue in the trend item;

[0093] For each cycle length, the peak-to-peak value of the pulsation term is obtained based on the difference between the maximum and minimum times of the pulsation term within the cycle length.

[0094] In some embodiments, determining a first time node corresponding to a maximum eigenvalue and a second time node corresponding to a minimum eigenvalue in the trend item includes:

[0095] Obtaining the first time node based on the time node in the trend item time linked list pointed to by the first pointer of the maximum eigenvalue;

[0096] Determine at least one cycle length based on the first time node and / or the second time node;

[0097] The second time node is obtained based on the time node in the trend item time linked list pointed to by the second pointer of the minimum eigenvalue.

[0098] Among them, since it is impossible to obtain the time node of the transient moment of the signal through the pulsation term, the corresponding time node can be determined through the trend term, and then mapped to the pulsation term to determine the peak-to-peak value of the pulsation term at the corresponding time node. For example, if the time node corresponding to the maximum eigenvalue of the trend term is 3s, then 2.8s to 3.2s can be taken and mapped to the pulsation term within this time interval, and the pulsation term data is used to calculate the peak-to-peak value. Specifically, the extraction formula for the time node corresponding to the maximum / minimum trend term eigenvalue may include: the time node corresponding to the maximum trend term eigenvalue = the pointer to the maximum eigenvalue of the trend term → the time list of the trend term; the time node corresponding to the minimum trend term eigenvalue = the pointer to the minimum eigenvalue of the trend term → the time list of the trend term.

[0099] In step S340, the average value of the peak-to-peak value of the pulsation item at different cycle lengths is calculated to obtain the peak-to-peak value of the pressure pulsation at the preset position.

[0100] In some embodiments, calculating the average of the peak-to-peak values ​​of the pulsation terms at different cycle lengths comprises:

[0101] Wherein, A is the average value, n is the number of different cycle lengths, and k is the sequence number of the cycle length.

[0102] Specifically, a signal mapping process can be performed on the trend and pulsation terms of the volute inlet pressure pulsation signal to obtain the peak-to-peak values ​​of the pulsation term of the volute inlet pressure pulsation signal at different periods with a confidence level of 97% (quantiles of 1.5% and 98.5%). A signal mapping process can be performed on the trend and pulsation terms of the draft tube inlet pressure pulsation signal obtained through the modal variation module to obtain the peak-to-peak values ​​of the pulsation term of the draft tube inlet pressure pulsation signal at different periods with a confidence level of 97% (quantiles of 1.5% and 98.5%). The average values ​​are respectively taken as the peak-to-peak values ​​of the volute inlet pressure pulsation and the draft tube inlet pressure pulsation under this transient operating condition.

[0103] In some embodiments, calculating the average of the peak-to-peak values ​​of the pulsation terms at different cycle lengths further includes:

[0104] Calculating the confidence level of the peak-to-peak value of the pulsation term corresponding to each cycle length;

[0105] The average value is calculated based on the peak-to-peak value of the pulsation item corresponding to the confidence level being greater than or equal to the confidence level threshold.

[0106] To improve the robustness of the analysis, a 97% confidence level (excluding the most extreme 1.5% and 98.5% data points) can be used to calculate the confidence intervals for the peak-to-peak values ​​of the pulsation term at different periods. This helps eliminate outliers and ensures the reliability of the results. The representative peak-to-peak values ​​for the transient operating conditions are determined based on the calculated average peak-to-peak values ​​of the pulsation term (taking into account the confidence interval) for the pressure pulsation signals at the volute inlet and the draft tube inlet. This provides an important quantitative indicator for evaluating system operating status and predicting potential failures.

[0107] See also Figure 4 , Figure 4 A schematic diagram of a method for detecting the peak-to-peak value of pressure pulsation of a hydropower station unit under transient conditions according to an embodiment of the present disclosure is shown. Figure 4In this test, the operating condition can be set as follows: a single unit operating normally at 306MW load is suddenly reduced to 100% of its rated load. This simulates the system response to an emergency shutdown or sudden load change in a hydropower station transient test scenario. Environmental conditions can include an upper reservoir water level of 580.47m and a lower reservoir water level of 229.76m, from which the head difference can be analyzed. Pressure sensors can be installed at the volute inlet and the draft tube inlet to continuously record pressure pulsation signals when a sudden load change occurs, providing raw data for subsequent analysis.

[0108] The pressure pulsation data detected by the sensor is analyzed using the variational mode decomposition (VMD) method to obtain the IMF components. These IMF components are then convolved to obtain the pressure pulsation trend and pulsation terms. For example, through signal mapping calculations, the maximum eigenvalue of the trend term at the volute inlet pressure measurement point occurs at 24.79 seconds, while the minimum eigenvalue of the trend term at the tailwater inlet pressure measurement point occurs at 22.51 seconds. The peak-to-peak value of the pressure pulsation within each cycle is calculated with a 97% confidence level for cycles of 1T, 1.2T, 1.3T, and finally 3.0T. It can be seen that the peak-to-peak value of the pressure pulsation at the volute inlet and draft tube inlet pressure measurement points varies smoothly over different time periods. The average value is taken as the final peak-to-peak value of the pressure pulsation. Based on field measurements, this result is more accurate than the peak-to-peak value of the pressure pulsation calculated over a single time period.

[0109] Therefore, the method according to the disclosed embodiment uses variational modal decomposition to decompose the pressure signal at the target location of the hydropower station unit to obtain trend terms and pulsation terms. Signal mapping is then used to calculate the peak-to-peak value of the pulsation term at different cycle lengths, thereby determining the peak-to-peak value of the pressure pulsation. This improves the accuracy of peak-to-peak pressure pulsation detection under transient conditions and provides reasonable and accurate technical support for related pressure data analysis.

[0110] It should be noted that the method of the embodiments of the present disclosure can be performed by a single device, such as a computer or server. The method of the embodiments of the present disclosure can also be applied in a distributed scenario, where multiple devices cooperate to perform the method. In such a distributed scenario, one of the multiple devices may only perform one or more steps of the method of the embodiments of the present disclosure, and the multiple devices will interact with each other to complete the method.

[0111] It should be noted that the above description is limited to some embodiments of the present disclosure. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in an order different from that described in the above embodiments and still achieve the desired results. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the specific order or sequential order shown to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0112] Based on the same technical concept, corresponding to any of the above embodiments and methods, the present disclosure also provides a device for detecting the peak-to-peak value of pressure pulsation of a hydropower station unit under transient conditions, see Figure 5 The device for detecting the peak-to-peak value of the pressure pulsation of the hydropower station unit under the transient working condition includes:

[0113] An acquisition module, configured to acquire a pressure pulsation signal at a preset position in a unit of the hydropower station;

[0114] a decomposition module, configured to decompose the pressure pulsation signal to obtain corresponding trend item signals and pulsation item signals;

[0115] A mapping module, configured to perform signal mapping processing on the trend item signal and the pulsation item signal to obtain peak-to-peak values ​​of the pulsation item at different cycle lengths;

[0116] The averaging module is used to calculate the average value of the peak-to-peak value of the pulsation item under different cycle lengths to obtain the peak-to-peak value of the pressure pulsation at the preset position.

[0117] For the convenience of description, the above devices are described as being functionally divided into various modules. Of course, when implementing the present disclosure, the functions of each module can be implemented in the same or multiple software and / or hardware.

[0118] In some embodiments, decomposing the pressure pulsation signal to obtain corresponding trend item signals and pulsation item signals includes:

[0119] Decomposing the pressure pulsation signal into a plurality of intrinsic mode function components;

[0120] Convolution and local feature extraction are performed on each of the intrinsic mode function components to obtain the trend item signal and the pulsation item signal.

[0121] In some embodiments, performing convolution and local feature extraction on each of the intrinsic mode function components to obtain the trend term signal and the pulsation term signal includes:

[0122] Extracting a low-frequency portion of the intrinsic mode function component to obtain the trend term signal;

[0123] The high-frequency part of the intrinsic mode function component is extracted to obtain the pulsating term signal.

[0124] In some embodiments, performing signal mapping processing on the trend item signal and the pulsation item signal to obtain peak-to-peak values ​​of the pulsation item at different cycle lengths includes:

[0125] Determining a first time node corresponding to a maximum eigenvalue and a second time node corresponding to a minimum eigenvalue in the trend item;

[0126] Determine at least one cycle length based on the first time node and / or the second time node;

[0127] For each cycle length, the peak-to-peak value of the pulsation term is obtained based on the difference between the maximum and minimum times of the pulsation term within the cycle length.

[0128] In some embodiments, determining a first time node corresponding to a maximum eigenvalue and a second time node corresponding to a minimum eigenvalue in the trend item includes:

[0129] Obtaining the first time node based on the time node in the trend item time linked list pointed to by the first pointer of the maximum eigenvalue;

[0130] The second time node is obtained based on the time node in the trend item time linked list pointed to by the second pointer of the minimum eigenvalue.

[0131] In some embodiments, calculating the average of the peak-to-peak values ​​of the pulsation terms at different cycle lengths comprises:

[0132] Wherein, A is the average value, n is the number of different cycle lengths, and k is the sequence number of the cycle length.

[0133] In some embodiments, calculating the average of the peak-to-peak values ​​of the pulsation terms at different cycle lengths further includes:

[0134] Calculating the confidence level of the peak-to-peak value of the pulsation term corresponding to each cycle length;

[0135] The average value is calculated based on the peak-to-peak value of the pulsation item corresponding to the confidence level being greater than or equal to the confidence level threshold.

[0136] The device of the above embodiment is used to implement the method for detecting the peak-to-peak value of pressure pulsation of the hydropower station unit under the corresponding transient working conditions in any of the above embodiments, and has the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0137] Based on the same technical concept, corresponding to any of the above-mentioned embodiment methods, the present disclosure also provides a non-transient computer-readable storage medium, which stores computer instructions, and the computer instructions are used to enable the computer to execute the method for detecting the peak-to-peak value of the pressure pulsation of the hydropower station unit under transient conditions as described in any of the above embodiments.

[0138] The computer-readable media of this embodiment include permanent and non-permanent, removable and non-removable media that can be used to store information by any method or technology. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, read-only compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device.

[0139] The computer instructions stored in the storage medium of the above embodiment are used to enable the computer to execute the method for detecting the peak-to-peak value of the pressure pulsation of the hydropower station unit under transient conditions as described in any of the above embodiments, and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0140] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present disclosure (including the claims) is limited to these examples. Within the scope of the present disclosure, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present disclosure as described above, which are not provided in detail for the sake of simplicity.

[0141] In addition, to simplify the description and discussion, and so as not to obscure the embodiments of the present disclosure, known power / ground connections to integrated circuit (IC) chips and other components may or may not be shown in the provided figures. In addition, devices may be shown in the form of block diagrams to avoid obscuring the embodiments of the present disclosure, and this also takes into account the fact that the details of the implementation of these block diagram devices are highly dependent on the platform on which the embodiments of the present disclosure are to be implemented (i.e., these details should be fully within the purview of those skilled in the art). Where specific details (e.g., circuits) are set forth to describe exemplary embodiments of the present disclosure, it will be apparent to those skilled in the art that the embodiments of the present disclosure may be implemented without these specific details or with variations in these specific details. Therefore, these descriptions should be considered illustrative rather than restrictive.

[0142] Although the present disclosure has been described in conjunction with specific embodiments thereof, many alternatives, modifications, and variations of these embodiments will be apparent to those skilled in the art based on the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) may use the embodiments discussed.

[0143] The embodiments of the present disclosure are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present disclosure should be included in the scope of protection of the present disclosure.

Claims

1. A method for detecting the peak-to-peak value of pressure pulsation of a hydropower station unit under transient conditions, characterized in that: include: Obtaining a pressure pulsation signal at a preset position in a unit of the hydropower station; Decomposing the pressure pulsation signal to obtain corresponding trend term signals and pulsation term signals, including: decomposing the pressure pulsation signal into a plurality of intrinsic mode function components by using a variational mode decomposition technique; performing convolution and local feature extraction on each of the intrinsic mode function components to obtain the trend term signals and the pulsation term signals; Performing signal mapping processing on the trend item signal and the pulsation item signal to obtain peak-to-peak values ​​of the pulsation item at different cycle lengths, including: determining a first time node corresponding to a maximum eigenvalue and a second time node corresponding to a minimum eigenvalue in the trend item; determining at least one cycle length based on the first time node and / or the second time node; and obtaining, for each cycle length, a peak-to-peak value of the pulsation item based on a time difference between a maximum value and a minimum value of the pulsation item within the cycle length; Calculating the average value of the peak-to-peak value of the pulsation term at different cycle lengths includes: , where A is the average value, n is the number of different cycle lengths, and k is the sequence number of the cycle length; The average value of the peak-to-peak value of the pulsation item at different cycle lengths is calculated to obtain the peak-to-peak value of the pressure pulsation at the preset position.

2. The method according to claim 1, characterized in that Performing convolution and local feature extraction on each of the intrinsic mode function components to obtain the trend term signal and the pulsation term signal includes: Extracting a low-frequency portion of the intrinsic mode function component to obtain the trend term signal; The high-frequency part of the intrinsic mode function component is extracted to obtain the pulsating term signal.

3. The method according to claim 1, characterized in that Determining a first time node corresponding to a maximum eigenvalue and a second time node corresponding to a minimum eigenvalue in the trend item includes: Obtaining the first time node based on the time node in the trend item time linked list pointed to by the first pointer of the maximum eigenvalue; The second time node is obtained based on the time node in the trend item time linked list pointed to by the second pointer of the minimum eigenvalue.

4. The method according to claim 1, characterized in that Calculating the average of the peak-to-peak values ​​of the pulsation term at different cycle lengths also includes: Calculating the confidence level of the peak-to-peak value of the pulsation term corresponding to each cycle length; The average value is calculated based on the peak-to-peak value of the pulsation item corresponding to the confidence level being greater than or equal to the confidence level threshold.

5. A device for detecting the peak-to-peak value of pressure pulsation of a hydropower station unit under transient conditions, characterized in that: include: An acquisition module, configured to acquire a pressure pulsation signal at a preset position in a unit of the hydropower station; a decomposition module, configured to decompose the pressure pulsation signal to obtain corresponding trend term signals and pulsation term signals, comprising: decomposing the pressure pulsation signal into a plurality of intrinsic mode function components by adopting a variational mode decomposition technique; and performing convolution and local feature extraction on each of the intrinsic mode function components to obtain the trend term signals and the pulsation term signals; a mapping module configured to perform signal mapping processing on the trend item signal and the pulsation item signal to obtain peak-to-peak values ​​of the pulsation item at different cycle lengths, comprising: determining a first time node corresponding to a maximum eigenvalue and a second time node corresponding to a minimum eigenvalue in the trend item; determining at least one cycle length based on the first time node and / or the second time node; and obtaining, for each cycle length, a peak-to-peak value of the pulsation item based on a time difference between a maximum value and a minimum value of the pulsation item within the cycle length; Calculating the average value of the peak-to-peak value of the pulsation term at different cycle lengths includes: , where A is the average value, n is the number of different cycle lengths, and k is the sequence number of the cycle length; The averaging module is used to calculate the average value of the peak-to-peak value of the pulsation item under different cycle lengths to obtain the peak-to-peak value of the pressure pulsation at the preset position.

6. The device according to claim 5, characterized in that Performing convolution and local feature extraction on each of the intrinsic mode function components to obtain the trend term signal and the pulsation term signal includes: Extracting a low-frequency portion of the intrinsic mode function component to obtain the trend term signal; The high-frequency part of the intrinsic mode function component is extracted to obtain the pulsating term signal.

7. The device according to claim 5, characterized in that Determining a first time node corresponding to a maximum eigenvalue and a second time node corresponding to a minimum eigenvalue in the trend item includes: Obtaining the first time node based on the time node in the trend item time linked list pointed to by the first pointer of the maximum eigenvalue; The second time node is obtained based on the time node in the trend item time linked list pointed to by the second pointer of the minimum eigenvalue.

8. The device according to claim 5, characterized in that Calculating the average of the peak-to-peak values ​​of the pulsation term at different cycle lengths also includes: Calculating the confidence level of the peak-to-peak value of the pulsation term corresponding to each cycle length; The average value is calculated based on the peak-to-peak value of the pulsation item corresponding to the confidence level being greater than or equal to the confidence level threshold.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method according to any one of claims 1 to 4 when executing the program. 10 . A non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are configured to cause a computer to execute the method according to claim 1 .

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