Health diagnosis system and method for hydraulic turbine based on multi-parameter energy-saving detection device

Abstract

The application provides a water turbine health diagnosis system and method based on a multi-parameter energy-saving detection device, which comprises a measurement and analysis device, a spring, sensing optical fibers and a support assembly. The support assembly vibrates synchronously with the water turbine. The spring is fixed at both ends with the support assembly and the water turbine. In the vibration direction of the water turbine, one end of the spring is higher than the other end. A group of sensing optical fiber segments are arranged on the upper and lower sides of the spring in the vibration direction of the water turbine. For each group of sensing optical fiber segments, the group of sensing optical fiber segments is composed of multiple sensing optical fiber segments aligned in the arrangement direction of the spring. One sensing optical fiber segment in the group is fixed between every two adjacent spring coils in the spring. The sensing optical fiber segments in the group are connected in series along the arrangement direction of the spring. The two groups of sensing optical fiber segments are connected in series and connected with the measurement and analysis device. The detection device has the advantages of small size, low cost, high measurement accuracy, and low energy consumption. One detection device can realize multiple parameter detection.

Description

Technical Field

[0001] This invention belongs to the field of turbine health monitoring, and specifically relates to a turbine health diagnosis system and method based on a multi-parameter energy-saving detection device. Background Technology

[0002] As the heart of a hydropower station, the turbine bears the crucial responsibility of converting water energy into electrical energy, and its stable and reliable operation is essential for the safety of the power system. However, with the increase in operating time, various potential problems gradually emerge, which not only affect the efficiency of the turbine but may also endanger the safety of the power station. Therefore, health diagnosis of the turbine is particularly important. Existing turbine health diagnosis methods typically include vibration analysis, noise analysis, oil analysis, and temperature analysis. However, current detection devices can only detect single parameters such as vibration, noise, or temperature. Moreover, the detection of these parameters usually uses electronic devices, which are not only large and costly but also require power to drive each electronic component, resulting in high energy consumption. Since the measurement of each parameter requires energy, the total energy consumption of the detection device is particularly high when performing multi-parameter detection. It is evident that existing turbine health diagnosis systems can only detect single parameters separately, and the detection devices are large, costly, and energy-intensive. Summary of the Invention

[0003] This invention provides a turbine health diagnosis system and method based on a multi-parameter energy-saving detection device, in order to solve the problems that current turbine health monitoring systems can only detect a single parameter separately, and that the detection devices are large in size, have high detection costs and high energy consumption.

[0004] According to a first aspect of the present invention, a turbine health diagnosis system based on a multi-parameter energy-saving detection device is provided, including a detection device and a measurement and analysis device. The detection device includes a spring, a sensing optical fiber, and a support assembly. The support assembly is disposed at a corresponding position on the turbine and vibrates synchronously with the turbine. One end of the spring is fixed to the support assembly, and the other end is fixed to the turbine. In the vibration direction of the turbine, one end of the spring is higher than the other end.

[0005] The spring is provided with a set of sensing fiber segments on the upper and lower sides of the vibration direction of the water turbine. Each set of sensing fiber segments consists of multiple sensing fiber segments aligned in the spring setting direction. One sensing fiber segment in the set is fixed between every two adjacent spring coils in the spring. Each sensing fiber segment in the set is connected in series along the spring setting direction. After the two sets of sensing fiber segments are connected in series, they are connected to the measurement and analysis device.

[0006] The measurement and analysis device determines the strain of each sensing fiber segment in the two sets of sensing fiber segments based on the scattered signals fed back from each sensing fiber segment. Based on the difference in strain between the corresponding upper and lower sensing fiber segments in the two sets of sensing fiber segments, it determines the vibration frequency and amplitude of the turbine. Based on the vibration frequency and amplitude of the turbine, it performs a health diagnosis on the turbine.

[0007] In one optional implementation, the support assembly includes a support member and a vibrating member. The vibrating member is disposed within the support member. The support member is fixed to the water turbine and vibrates synchronously with the water turbine. When the water turbine vibrates, the vibrating member moves back and forth relative to the support member along the vibration direction of the water turbine. One end of the spring is fixed to the vibrating member, and the other end is fixed to the water turbine.

[0008] In another alternative implementation, the spring bends when the turbine vibrates.

[0009] According to a second aspect of the present invention, a diagnostic method for the above-described turbine health diagnostic system based on a multi-parameter energy-saving detection device is provided, wherein the measurement and analysis device performs the following steps:

[0010] Step S1: Set the range of the monitorable vibration period, and determine the strain of each sensing fiber segment in each group of sensing fiber segments on the spring within the set vibration period.

[0011] Step S2: For each sensing fiber segment in the first group of sensing fiber segments, determine the minimum strain of the sensing fiber segment within the maximum vibration period. For the first group of sensing fiber segments, select the minimum strain among the minimum strains corresponding to each sensing fiber segment in the first group as the minimum target strain of the spring. For each sensing fiber segment in the second group of sensing fiber segments, determine the maximum strain of the sensing fiber segment within the maximum vibration period. For the second group of sensing fiber segments, select the maximum strain among the maximum strains corresponding to each sensing fiber segment in the second group as the maximum target strain of the spring.

[0012] Step S3: Subtract the absolute value of the minimum target strain from the maximum target strain to obtain the strain difference that reflects the degree of spring bending;

[0013] Step S4: Determine the vibration period of the turbine based on the time interval between two adjacent minimum target strains or two adjacent maximum target strains, thereby determining the vibration frequency at the corresponding location of the turbine.

[0014] Step S5: Based on the correspondence between the strain difference and the turbine amplitude at the corresponding vibration frequency, determine the amplitude at the corresponding position of the turbine according to the obtained strain difference.

[0015] The beneficial effects of this invention are:

[0016] 1. This invention designs a detection device. One end of a spring is fixed to a support assembly, and the other end is fixed to a water turbine. The support assembly vibrates synchronously with the water turbine, and the spring bends with the vibration of the water turbine. A set of sensing fiber segments is set on the upper and lower sides of the spring in the vibration direction of the water turbine. The vibration frequency and amplitude of the water turbine can be determined by the difference in strain between the corresponding upper and lower sensing fiber segments in the two sets of sensing fiber segments. Since the difference in strain eliminates the influence of the water turbine temperature, the accuracy of the water turbine vibration characteristics determined by the strain is higher. This invention uses only three parts for vibration detection: a support assembly, a spring, and sensing fiber. It is small in size, low in cost, and has high measurement accuracy using sensing fiber. Moreover, it does not require a power supply to drive various electronic components, resulting in low energy consumption. This invention can measure both vibration frequency and amplitude parameters. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of an embodiment of the turbine health diagnosis system based on a multi-parameter energy-saving detection device according to the present invention;

[0018] Figure 2 This is a schematic diagram of another embodiment of the turbine health diagnosis system based on a multi-parameter energy-saving detection device of the present invention;

[0019] Figure 3 This is a flowchart of another embodiment of the turbine health diagnosis method of the present invention. Detailed Implementation

[0020] To enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention, and to make the above-mentioned objectives, features and advantages of the embodiments of the present invention more apparent and understandable, the technical solutions in the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0021] In the description of this invention, unless otherwise specified and limited, it should be noted that the term "connection" should be interpreted broadly. For example, it can be a mechanical connection or an electrical connection, or it can be a connection between two internal components. It can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above term according to the specific circumstances.

[0022] See Figure 1This is a schematic diagram of an embodiment of the turbine health diagnosis system based on a multi-parameter energy-saving detection device according to the present invention. The system may include a detection device and a measurement and analysis device. The detection device may include a spring 1, a sensing optical fiber, and a support assembly 2. The support assembly 2 is positioned at a corresponding location on the turbine 3 and vibrates synchronously with the turbine 3. One end of the spring 1 is fixed to the support assembly 2, and the other end is fixed to the turbine 3. In the vibration direction of the turbine 3, one end of the spring 1 is higher than the other end, and initially, the spring 1 can be in a normal or stretched state. A set of sensing optical fiber segments 4 and 5 are respectively provided on the upper and lower sides of the spring 1 in the vibration direction of the turbine 3. Each set of sensing optical fiber segments consists of multiple sensing optical fiber segments aligned in the direction of the spring 1. One sensing optical fiber segment from this set is fixed between every two adjacent spring coils in the spring 1. The sensing optical fiber segments in this set are connected in series along the direction of the spring. Then, the two sets of sensing optical fiber segments 4 and 5 are connected in series again and connected to the measurement and analysis device.

[0023] The measurement and analysis device determines the strain of each sensing fiber segment in the two sets of sensing fiber segments based on the scattered signals fed back from each sensing fiber segment. Based on the difference in strain between the corresponding upper and lower sensing fiber segments in the two sets of sensing fiber segments, it determines the vibration frequency and amplitude of the turbine. Based on the vibration frequency and amplitude of the turbine, it performs a health diagnosis on the turbine.

[0024] In this embodiment, the spring bends due to inertia when the turbine vibrates, and the turbine generates heat during operation. Therefore, the sensing fiber segment on the spring will not only experience strain due to the spring's bending but also due to temperature. The degree of spring bending is related to the turbine's vibration frequency and amplitude. If the entire sensing fiber is laid along the spring's direction, it will also experience strain due to the spring's bending, but this strain is also affected by temperature, leading to lower accuracy in measuring the strain caused by the spring's bending. To eliminate the influence of temperature, the present invention provides a set of sensing fiber segments on the upper and lower sides of the spring in the direction of turbine vibration. Each set of sensing fiber segments consists of multiple sensing fiber segments aligned in the direction of spring setting. Since the more curved the spring as a whole, the greater the difference between the bending length of the upper sensing fiber segment and the lower sensing fiber segment at the point of maximum curvature, the greater the difference between the strain of the upper sensing fiber segment and the strain of the lower sensing fiber segment at the point of maximum curvature. In addition, both the upper and lower sensing fiber segments are affected by temperature. Subtracting the strains of the two segments can eliminate the influence of temperature on the strain measurement corresponding to spring bending. Therefore, by establishing the relationship between strain difference and spring bending, the bending characteristics of the spring can be accurately measured, thereby determining the vibration characteristics of the turbine.

[0025] As can be seen from the above embodiments, the present invention designs a detection device. This detection device fixes one end of a spring to a support assembly and the other end to a water turbine. The support assembly vibrates synchronously with the water turbine, and the spring bends with the vibration of the water turbine. A set of sensing fiber segments is respectively set on the upper and lower sides of the spring in the vibration direction of the water turbine. Based on the difference in strain between the corresponding upper and lower sensing fiber segments in the two sets of sensing fiber segments, the vibration frequency and amplitude of the water turbine can be determined. Since the difference in strain eliminates the influence of the water turbine temperature, the accuracy of the water turbine vibration characteristics determined based on the strain is higher. The vibration detection of the present invention only uses three parts: a support assembly, a spring, and sensing fiber. It is small in size, low in cost, and has high measurement accuracy using sensing fiber. Moreover, it does not require a power supply to drive various electronic components, resulting in low energy consumption. The present invention can measure both vibration frequency and amplitude parameters.

[0026] See Figure 2 This is a schematic diagram of another embodiment of the turbine health diagnosis system based on a multi-parameter energy-saving detection device according to the present invention. Figure 2 and Figure 1 The difference between the turbine health diagnosis system based on the multi-parameter energy-saving detection device shown is that the support component 2 may include a support member 6 and a vibrating member 7. The vibrating member 7 is located inside the support member 6. The support member 6 is fixed on the turbine 3 and vibrates synchronously with the turbine 3. When the turbine 3 vibrates, the vibrating member 7 moves back and forth relative to the support member 6 along the vibration direction of the turbine. One end of the spring 1 is fixed to the vibrating member 7, and the other end is fixed to the turbine 3.

[0027] In this embodiment, the vibration direction of both the vibrating element and the turbine can be vertical. Typically, when the vibrating element 7 moves upward or downward relative to the support 6 to its maximum amplitude, the spring's curvature is at its maximum. However, as the amplitude of the vibrating element 7 increases, the spring's curvature decreases due to the tensile force exerted by the vibrating element 7 on the spring. Correspondingly, the strain difference between the upper and lower sensing fiber segments at the point of maximum spring curvature decreases. That is, the magnitude of the vibration amplitude of the vibrating element 7 affects the magnitude of the strain difference. Therefore, when determining the turbine's vibration characteristics through the strain difference, the differences in strain differences between different vibration characteristics are significant. Thus, the turbine's vibration frequency and amplitude can be determined more accurately based on the strain difference.

[0028] The support assembly of this invention includes a vibrating element and a supporting element. The supporting element vibrates synchronously with the water turbine, and the vibrating element moves back and forth relative to the supporting element in the vibration direction of the water turbine. One end of the spring is fixed to the vibrating element, and the other end is fixed to the water turbine. Introducing the vibrating element can affect the bending degree of the spring, thereby increasing the difference in strain difference corresponding to different vibration characteristics of the water turbine. Therefore, the vibration frequency and amplitude of the water turbine can be determined more accurately based on the strain difference.

[0029] As can be seen from the above embodiments, the present invention designs a detection device. This detection device fixes one end of a spring to a support assembly and the other end to a water turbine. The support assembly vibrates synchronously with the water turbine, and the spring bends with the vibration of the water turbine. A set of sensing fiber segments is respectively set on the upper and lower sides of the spring in the vibration direction of the water turbine. Based on the difference in strain between the corresponding upper and lower sensing fiber segments in the two sets of sensing fiber segments, the vibration frequency and amplitude of the water turbine can be determined. Since the difference in strain eliminates the influence of the water turbine temperature, the accuracy of the water turbine vibration characteristics determined based on the strain is higher. The vibration detection of the present invention only uses three parts: a support assembly, a spring, and sensing fiber. It is small in size, low in cost, and has high measurement accuracy using sensing fiber. Moreover, it does not require a power supply to drive various electronic components, resulting in low energy consumption. The present invention can measure both vibration frequency and amplitude parameters.

[0030] In addition, the present invention also provides a diagnostic method for the above-mentioned turbine health diagnostic system based on a multi-parameter energy-saving detection device, wherein the measurement and analysis device performs the following steps:

[0031] Step S1: Set the range of the monitorable vibration period, and determine the strain of each sensing fiber segment in each group of sensing fiber segments on the spring within the set vibration period.

[0032] Step S2: For each sensing fiber segment in the first group of sensing fiber segments, determine the minimum strain of the sensing fiber segment within the maximum vibration period. For the first group of sensing fiber segments, select the minimum strain among the minimum strains corresponding to each sensing fiber segment in the first group as the minimum target strain of the spring. For each sensing fiber segment in the second group of sensing fiber segments, determine the maximum strain of the sensing fiber segment within the maximum vibration period. For the second group of sensing fiber segments, select the maximum strain among the maximum strains corresponding to each sensing fiber segment in the second group as the maximum target strain of the spring.

[0033] Step S3: Subtract the absolute value of the minimum target strain from the maximum target strain to obtain the strain difference that reflects the degree of spring bending;

[0034] Step S4: Determine the vibration period of the turbine based on the time interval between two adjacent minimum target strains or two adjacent maximum target strains, thereby determining the vibration frequency at the corresponding location of the turbine.

[0035] Step S5: Based on the correspondence between the strain difference and the turbine amplitude at the corresponding vibration frequency, determine the amplitude at the corresponding position of the turbine according to the obtained strain difference.

[0036] As can be seen from the above embodiments, the method of the present invention is based on a detection device, which can determine the vibration frequency and amplitude of the turbine based on the strain difference between the corresponding upper and lower sensing fiber segments in its two sets of sensing fiber segments. It can also detect the temperature at its location based on the detection device, thereby realizing multi-parameter measurement. Since one detection device can detect multiple parameters and the energy consumption of the detection device is particularly low, the energy-saving effect of the present invention is very obvious compared to using different detection devices to measure different parameters.

[0037] Other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of the invention are indicated by the following claims.

[0038] It should be understood that the present invention is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is defined solely by the appended claims.

Claims

1. A turbine health diagnosis system based on a multi-parameter energy-saving detection device, characterized in that, It includes a detection device and a measurement and analysis device. The detection device includes a spring, a sensing optical fiber, and a support assembly. The support assembly is set at a corresponding position on the water turbine and vibrates synchronously with the water turbine. One end of the spring is fixed to the support assembly, and the other end is fixed to the water turbine. In the vibration direction of the water turbine, one end of the spring is higher than the other end. The spring is provided with a set of sensing fiber segments on the upper and lower sides of the vibration direction of the water turbine. Each set of sensing fiber segments consists of multiple sensing fiber segments aligned in the spring setting direction. One sensing fiber segment in the set is fixed between every two adjacent spring coils in the spring. Each sensing fiber segment in the set is connected in series along the spring setting direction. After the two sets of sensing fiber segments are connected in series, they are connected to the measurement and analysis device. The measurement and analysis device determines the strain of each sensing fiber segment in the two sets of sensing fiber segments based on the scattered signals fed back from each sensing fiber segment. Based on the difference in strain between the corresponding upper and lower sensing fiber segments in the two sets of sensing fiber segments, it determines the vibration frequency and amplitude of the turbine. Based on the vibration frequency and amplitude of the turbine, it performs a health diagnosis on the turbine.

2. The turbine health diagnosis system based on a multi-parameter energy-saving detection device according to claim 1, characterized in that, The support assembly includes a support member and a vibrating member. The vibrating member is disposed inside the support member. The support member is fixed to the water turbine and vibrates synchronously with the water turbine. When the water turbine vibrates, the vibrating member moves back and forth relative to the support member along the vibration direction of the water turbine. One end of the spring is fixed to the vibrating member, and the other end is fixed to the water turbine.

3. The turbine health diagnosis system based on a multi-parameter energy-saving detection device according to claim 1 or 2, characterized in that, The spring bends when the turbine vibrates.

4. A diagnostic method for a turbine health diagnostic system based on a multi-parameter energy-saving detection device as described in any one of claims 1 to 3, characterized in that, The measurement and analysis device performs the following steps: Step S1: Set the range of the monitorable vibration period, and determine the strain of each sensing fiber segment in each group of sensing fiber segments on the spring within the set vibration period. Step S2: For each sensing fiber segment in the first group of sensing fiber segments, determine the minimum strain of the sensing fiber segment within the maximum vibration period. For the first group of sensing fiber segments, select the minimum strain among the minimum strains of each sensing fiber segment in the first group as the minimum target strain of the spring. For each sensing fiber segment in the second group of sensing fiber segments, determine the maximum strain of the sensing fiber segment within the maximum vibration period. For the second group of sensing fiber segments, select the maximum strain among the maximum strains of each sensing fiber segment in the second group as the maximum target strain of the spring. Step S3: Subtract the absolute value of the minimum target strain from the maximum target strain to obtain the strain difference that reflects the degree of spring bending; Step S4: Determine the vibration period of the turbine based on the time interval between two adjacent minimum target strains or two adjacent maximum target strains, thereby determining the vibration frequency at the corresponding location of the turbine. Step S5: Based on the correspondence between the strain difference and the turbine amplitude at the corresponding vibration frequency, determine the amplitude at the corresponding position of the turbine according to the obtained strain difference.

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