Turbine last-stage long blade vibration monitoring system under peak regulation working condition

Abstract

The invention provides a steam turbine last-stage long blade vibration monitoring system under a peak regulation working condition, and belongs to the technical field of steam turbines. The intelligent sensor module is used for accurately collecting vibration signals, the efficient signal processing module is used for carrying out filtering, amplification and digital processing on obtained displacement signals and acceleration signals through an edge computing technology, and the intelligent data analysis module is used for deeply analyzing the processed signals based on a deep learning algorithm and accurately extracting characteristic parameters. The visual display module dynamically presents characteristic parameters in real time through a virtual reality technology; and the sensitive alarm module timely triggers an alarm signal when the parameters exceed a preset threshold value. The system realizes real-time and accurate monitoring of vibration of the last-stage long blade of the steam turbine, can sensitively perceive abnormal conditions, provides real-time guidance for operators, and provides solid guarantee for safe and stable operation of the steam turbine.

Description

Technical Field

[0001] The present invention belongs to the technical field of steam turbines, and in particular, relates to a vibration monitoring system for a last-stage long blade of a steam turbine under peak load conditions. Background Art

[0002] With the development of industry and the increase in energy demand, steam turbines, as important power generation equipment, have received extensive attention for their operating efficiency and safety. In recent years, low-pressure blade fractures of steam turbines in domestic thermal power units with deep peak regulation and heating cylinder cutting have occurred frequently. The long blades of the last stage of the steam turbine are subjected to complex steam flow excitation and centrifugal forces during operation. When crossing the blade stress hump area, the blade vibration increases rapidly. Excessive vibration may cause blade fatigue damage, cracks or even fractures, seriously affecting the safe operation of the steam turbine. Therefore, real-time monitoring of the vibration of the long blades of the last stage of the steam turbine is of great significance.

[0003] However, existing vibration monitoring methods and systems have some limitations, such as low monitoring accuracy, inability to adapt to complex operating conditions, and difficulty in accurately capturing high-frequency vibrations and stress humps of blades.

[0004] Limitations in monitoring accuracy: Existing monitoring systems mostly use contact sensors, which may not only cause damage to the blades, but also their measurement accuracy is limited by the physical contact of the sensors and environmental factors such as temperature and humidity.

[0005] Insufficient adaptability: The vibration characteristics of the blades of the steam turbine will change under different operating conditions. Existing systems often lack sufficient adaptability and cannot accurately capture the vibration characteristics of the blades under variable conditions.

[0006] Difficulty in capturing high-frequency vibrations: Under certain conditions, the long blades of the last stage of the steam turbine may generate high-frequency vibrations, which are important signals of early blade damage. Existing technologies make it difficult to effectively capture and analyze these high-frequency signals.

[0007] Difficulties in monitoring stress hump areas: When a blade passes through a stress hump area, its vibration response changes dramatically, which is a high-risk area for blade fatigue damage and cracks. Existing monitoring systems are often unable to accurately identify and evaluate the vibration state of this area. Summary of the invention

[0008] In order to overcome the shortcomings of the prior art, the present invention proposes a vibration monitoring system for the last-stage long blades of a steam turbine under peak load conditions, which realizes real-time and accurate monitoring of the vibration of the last-stage long blades of the steam turbine.

[0009] The present invention is achieved through the following technical solutions:

[0010] A vibration monitoring system for the last long blades of a steam turbine under peak load conditions:

[0011] The vibration monitoring system includes a sensor module, a data acquisition module, a signal processing module and a display alarm module;

[0012] The sensor module is used to collect vibration data of the last-stage long blades of the steam turbine;

[0013] The data acquisition module includes a filtering circuit, an amplifying circuit and an analog-to-digital conversion circuit, which filters and amplifies the vibration signal collected by the sensor module, then performs analog-to-digital conversion, and transmits the processed data to the signal processing module;

[0014] The signal processing module performs spectrum analysis and feature extraction on the received digital signal to obtain frequency, amplitude and phase parameters of blade vibration;

[0015] The display alarm module is connected to the signal processing module and consists of a liquid crystal display and an audible and visual alarm. It is used to display the vibration monitoring results of the blades and the vibration data of the stress hump area during the cylinder cutting process in real time, and to send out an audible and visual alarm signal when the vibration parameters exceed the preset threshold, while providing guidance for the cylinder cutting operation.

[0016] Furthermore, the sensor module includes 3 non-contact eddy current sensors and 8 acceleration sensors.

[0017] Furthermore, the three non-contact eddy current sensors are spaced 30 degrees apart and installed on the top of the partition or the cylinder corresponding to the tip of the last-stage long blade of the steam turbine.

[0018] Furthermore, the axial distribution of the three non-contact eddy current sensors is not on the same cross section, and the axial distance between the two non-contact eddy current sensors that are farthest apart in space is not greater than the absolute expansion value of the low-pressure rotor.

[0019] Furthermore, the eight acceleration sensors transmit information to the data acquisition module by wireless signal transmission, and the eight acceleration sensors are evenly distributed in the dynamic balancing holes at the root of the last-stage blade, without affecting the unbalanced mass distribution of the entire rotor.

[0020] Furthermore, the signal processing module performs spectrum analysis through Fast Fourier Transform (FFT) and extracts characteristic parameters of the vibration signal through a wavelet transform algorithm.

[0021] Furthermore, the vibration monitoring system also includes a storage module and a communication module;

[0022] The storage module is used to store vibration data and analysis results, and the data acquisition accuracy reaches 1ms;

[0023] The communication module transmits the monitoring data and alarm information to the remote monitoring terminal.

[0024] A method for monitoring vibration of the last-stage long blades of a steam turbine under peak load conditions:

[0025] The method comprises the following steps:

[0026] Step 1: Collect vibration data of the last-stage long blades of the steam turbine in real time through the sensor module;

[0027] Step 2: The vibration signal collected by the sensor module is filtered and amplified by the data acquisition module, and then analog-to-digital conversion is performed, and the processed data is transmitted to the signal processing module;

[0028] Step 3: Perform spectrum analysis and feature extraction on the received digital signal through the signal processing module to obtain the frequency, amplitude and phase of the blade vibration;

[0029] Step 4: The vibration monitoring results of the blades and the vibration data of the stress hump area during the cylinder cutting process are displayed in real time through the display alarm module, and an audible and visual alarm signal is issued when the vibration parameters exceed the preset threshold, while providing guidance for the cylinder cutting operation.

[0030] An electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above method when executing the computer program.

[0031] A computer-readable storage medium is used to store computer instructions, and when the computer instructions are executed by a processor, the steps of the above method are implemented.

[0032] Beneficial effects of the present invention

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1. High-precision monitoring: This system uses high-precision non-contact eddy current sensors and acceleration sensors, combined with advanced signal processing algorithms, to achieve high-precision monitoring of blade vibration and accurately capture tiny vibration changes; the combination of non-contact eddy current sensors and acceleration sensors can comprehensively and accurately obtain the vibration information of the long blades of the last stage of the turbine.

[0035] 2. Adapt to complex working conditions: Whether in high-load operation of the turbine or deep peak regulation and other complex working conditions, the system can work stably and reliably and provide accurate vibration monitoring data; advanced signal processing algorithms improve monitoring accuracy and reliability, and can effectively identify small vibration changes and complex vibration patterns of the blades.

[0036] 3. Strong real-time performance: It can collect, process and display the vibration data of the blades in real time, so that the operating personnel can timely understand the operating status of the blades and respond quickly; Intelligent alarm and diagnosis: Through preset thresholds and intelligent analysis, when the blade vibration is abnormal, the system can promptly issue an alarm signal and provide preliminary fault diagnosis information to help technicians quickly locate the problem; real-time display and alarm functions help operating personnel to promptly detect abnormal vibration of the blades and take appropriate measures to avoid accidents.

[0037] 4. Data storage and remote communication functions facilitate the analysis and management of monitoring data by technicians, and provide strong support for turbine maintenance and fault diagnosis.

[0038] 5. Easy to install and maintain: The sensor is easy to install, with little change to the original structure of the turbine. The system has good stability and maintainability, reducing the cost of use. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of the structure of the blade vibration monitoring system of the present invention.

[0040] Figure 2 Schematic diagram of sensor installation for blade vibration monitoring system. DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] The experimental methods used in the following examples are conventional methods unless otherwise specified. The materials, reagents, methods and instruments used are conventional materials, reagents, methods and instruments in the art unless otherwise specified, and can be obtained through commercial channels by those skilled in the art.

[0043] A vibration monitoring system for the last long blades of a steam turbine under peak load conditions:

[0044] The vibration monitoring system includes a sensor module, a data acquisition module, a signal processing module and a display alarm module;

[0045] The sensor module is used to collect vibration displacement and acceleration data of the last-stage long blades of the steam turbine;

[0046] The sensor module includes three non-contact eddy current sensors (displacement sensors) and eight acceleration sensors.

[0047] The three non-contact eddy current sensors are spaced 30 degrees apart and are installed on the top of a partition or a cylinder corresponding to the tip of a long blade of a last stage of a low-pressure rotor of a steam turbine.

[0048] The axial distribution of the three non-contact eddy current sensors is not on the same cross section, and the axial distance between the two non-contact eddy current sensors that are farthest apart in space is not greater than the absolute expansion value of the low-pressure rotor.

[0049] The eight acceleration sensors transmit information to the data acquisition module by wireless signal transmission, and the eight acceleration sensors are evenly distributed in the dynamic balancing holes at the root of the last-stage blades of the low-pressure rotor, without affecting the unbalanced mass distribution of the entire rotor.

[0050] The data acquisition module includes a filtering circuit, an amplifying circuit and an analog-to-digital conversion circuit, and uses a high-performance A / D conversion chip to filter and amplify the vibration signal collected by the sensor module, and then performs analog-to-digital conversion, and transmits the processed data to the signal processing module;

[0051] The signal processing module uses advanced digital signal processing algorithms to perform spectrum analysis and feature extraction on the received digital signal to obtain key parameters such as frequency, amplitude and phase of blade vibration;

[0052] The signal processing module performs spectrum analysis through Fast Fourier Transform (FFT) and extracts characteristic parameters of the vibration signal through a wavelet transform algorithm.

[0053] The display alarm module is connected to the signal processing module and consists of a liquid crystal display and an audible and visual alarm. It is used to display the vibration monitoring results of the blades and the vibration data of the stress hump area during the cylinder cutting process in real time, and to send out an audible and visual alarm signal when the vibration parameters exceed the preset threshold, while providing guidance for the cylinder cutting operation.

[0054] The vibration monitoring system also includes a storage module and a communication module;

[0055] The storage module is used to store vibration data and analysis results, and the data acquisition accuracy reaches 1ms;

[0056] The communication module transmits the monitoring data and alarm information to the remote monitoring terminal.

[0057] A method for monitoring vibration of the last-stage long blades of a steam turbine under peak load conditions:

[0058] The method comprises the following steps:

[0059] Step 1: Collect vibration data of the last-stage long blades of the steam turbine in real time through the sensor module;

[0060] Step 2: The vibration signal collected by the sensor module is filtered and amplified by the data acquisition module, and then analog-to-digital conversion is performed, and the processed data is transmitted to the signal processing module;

[0061] Step 3: Perform spectrum analysis and feature extraction on the received digital signal through the signal processing module to obtain the frequency, amplitude and phase of the blade vibration;

[0062] Step 4: The vibration monitoring results of the blades and the vibration data of the stress hump area during the cylinder cutting process are displayed in real time through the display alarm module, and an audible and visual alarm signal is issued when the vibration parameters exceed the preset threshold, while providing guidance for the cylinder cutting operation.

[0063] An electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above method when executing the computer program.

[0064] A computer-readable storage medium is used to store computer instructions, and when the computer instructions are executed by a processor, the steps of the above method are implemented.

[0065] The memory in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory, ROM, a programmable read-only memory, PROM, an erasable programmable read-only memory, EPROM, an electrically erasable programmable read-only memory, EEPROM, or a flash memory. The volatile memory may be a random access memory, RAM, which is used as an external cache. By way of example but not limitation, many forms of RAM are available, such as static random access memory static RAM, SRAM, dynamic random access memory dynamic RAM, DRAM, synchronous dynamic random access memory synchronous DRAM, SDRAM, double data rate synchronous dynamic random access memory double data rate SDRAM, DDR SDRAM, enhanced synchronous dynamic random access memory enhanced SDRAM, ESDRAM, synchronous link dynamic random access memory synchlink DRAM, SLDRAM, and direct memory bus random access memory direct rambus RAM, DR RAM. It should be noted that memory of the methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0066] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website site, computer, server or data center through a wired method such as coaxial cable, optical fiber, digital subscriber line digital subscriber line, DSL or wireless such as infrared, wireless, microwave, etc. to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or data center that includes one or more available media integrated. The available medium can be a magnetic medium such as a floppy disk, a hard disk, a tape, an optical medium such as a high-density digital video disc digital video disc, DVD, or a semiconductor medium such as a solid state hard disk solid state disc, SSD, etc.

[0067] In the implementation process, each step of the above method can be completed by an integrated logic circuit of hardware in a processor or an instruction in the form of software. The steps of the method disclosed in conjunction with the embodiment of the present application can be directly embodied as a hardware processor for execution, or a combination of hardware and software modules in a processor for execution. The software module can be located in a storage medium mature in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor reads the information in the memory and completes the steps of the above method in conjunction with its hardware. To avoid repetition, it is not described in detail here.

[0068] It should be noted that the processor in the embodiment of the present application can be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method embodiment can be completed by an integrated logic circuit of hardware in the processor or an instruction in the form of software. The above processor can be a general-purpose processor, a digital signal processor DSP, an application-specific integrated circuit ASIC, a field programmable gate array FPGA or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in the embodiment of the present application can be directly embodied as a hardware decoding processor to perform, or the hardware and software modules in the decoding processor can be combined to perform. The software module can be located in a mature storage medium in the field such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

[0069] The above is a detailed introduction to the vibration monitoring system for the last stage long blades of a steam turbine under peak-shaving conditions proposed by the present invention, and the principles and implementation methods of the present invention are explained. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for general technical personnel in this field, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A vibration monitoring system for the last long blade of a steam turbine under peak load conditions, characterized in that: The vibration monitoring system includes a sensor module, a data acquisition module, a signal processing module and a display alarm module; The sensor module is used to collect vibration data of the last-stage long blades of the steam turbine; The data acquisition module includes a filtering circuit, an amplifying circuit and an analog-to-digital conversion circuit, which filters and amplifies the vibration signal collected by the sensor module, then performs analog-to-digital conversion, and transmits the processed data to the signal processing module; The signal processing module performs spectrum analysis and feature extraction on the received digital signal to obtain frequency, amplitude and phase parameters of blade vibration; The display alarm module is connected to the signal processing module and consists of a liquid crystal display and an audible and visual alarm. It is used to display the vibration monitoring results of the blades and the vibration data of the stress hump area during the cylinder cutting process in real time, and to send out an audible and visual alarm signal when the vibration parameters exceed the preset threshold, while providing guidance for the cylinder cutting operation.

2. The vibration monitoring system according to claim 1, characterized in that: The sensor module includes three non-contact eddy current sensors and eight acceleration sensors.

3. The vibration monitoring system according to claim 2, characterized in that: The three non-contact eddy current sensors are spaced 30 degrees apart and are mounted on the top of a partition or a cylinder corresponding to the tip of a long blade at the last stage of a steam turbine.

4. The vibration monitoring system according to claim 3, characterized in that: The axial distribution of the three non-contact eddy current sensors is not on the same cross section, and the axial distance between the two non-contact eddy current sensors that are farthest apart in space is not greater than the absolute expansion value of the low-pressure rotor.

5. The vibration monitoring system according to claim 4, characterized in that: The eight acceleration sensors transmit information to the data acquisition module by wireless signal transmission, and the eight acceleration sensors are evenly distributed in the dynamic balancing holes at the root of the last-stage blade, without affecting the unbalanced mass distribution of the entire rotor.

6. The vibration monitoring system according to claim 5, characterized in that: The signal processing module performs spectrum analysis through Fast Fourier Transform (FFT) and extracts characteristic parameters of the vibration signal through a wavelet transform algorithm.

7. The vibration monitoring system according to claim 6, characterized in that: The vibration monitoring system also includes a storage module and a communication module; The storage module is used to store vibration data and analysis results, and the data acquisition accuracy reaches 1ms; The communication module transmits the monitoring data and alarm information to the remote monitoring terminal.

8. A monitoring method for a vibration monitoring system for a last-stage long blade of a steam turbine under peak load conditions according to any one of claims 1 to 7, characterized in that: The method comprises the following steps: Step 1: Collect vibration data of the last-stage long blades of the steam turbine in real time through the sensor module; Step 2: The vibration signal collected by the sensor module is filtered and amplified by the data acquisition module, and then analog-to-digital conversion is performed, and the processed data is transmitted to the signal processing module; Step 3: Perform spectrum analysis and feature extraction on the received digital signal through the signal processing module to obtain the frequency, amplitude and phase of the blade vibration; Step 4: The vibration monitoring results of the blades and the vibration data of the stress hump area during the cylinder cutting process are displayed in real time through the display alarm module, and an audible and visual alarm signal is issued when the vibration parameters exceed the preset threshold.

9. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method described in claim 8 are implemented.

10. A computer-readable storage medium for storing computer instructions, characterized in that: When the computer instructions are executed by a processor, the steps of the method described in claim 8 are implemented.

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