Automatic protection method and system for breeze generator set

Abstract

The invention relates to the field of generator set monitoring, in particular to a breeze generator set automatic protection method and system, and the method comprises the steps: obtaining parameters of each breeze generator set at each moment; taking the to-be-detected breeze generator set as a target breeze generator set, and selecting any breeze generator set as a reference generator set of the target breeze generator set; dividing the plurality of moments to obtain a plurality of time periods, and drawing a first curve about the wind speed and the output power of the target breeze generator set in each time period and a second curve about the reference generator set; and constructing a fault evaluation function of the target breeze generator set, obtaining the maximum value of the fault evaluation values according to the fault evaluation function, and giving out an early warning prompt in response to the situation that the maximum value is greater than a preset threshold value. The breeze generator set can be accurately monitored, further acceleration of faults of the reference generator set is effectively avoided, and the effect of automatic protection of the breeze generator set is achieved.

Description

Technical Field

[0001] The present invention relates to the field of generator set monitoring, and in particular to an automatic protection method and system for a breeze generator set. Background Art

[0002] A micro-wind generator is a small-scale wind power generation technology designed to generate electricity using lower wind speeds, and is usually used for power supply in homes, agriculture or small commercial places. Micro-wind generators are characterized by small power generation, but their advantages are that the equipment is relatively simple and the installation is flexible, which is suitable for areas with less abundant wind resources. Micro-wind generators are usually installed in clusters, that is, multiple micro-wind generators are installed in a certain range of sites to facilitate equipment management and maintenance. However, during the operation of micro-wind generators, it is necessary to monitor the operating status of micro-wind generators so that they are in good operating condition.

[0003] A Chinese patent with announcement number CN109869286B discloses a method for monitoring the vibration status of a wind turbine generator set, comprising the following steps: arranging multiple sensor groups along the vertical direction on the inner wall of a wind turbine tower, each sensor group including at least four low-frequency sensors evenly arranged along the same circumference, collecting low-frequency vibration signals of the wind turbine generator set in a natural state; performing an initial estimation of the natural excitation operating mode of the wind turbine generator set based on the collected low-frequency vibration signals, and obtaining a transfer function by Fourier transforming the low-frequency vibration signal, taking out finite data fitting of the transfer function at each modal frequency to obtain the operating modal parameters, and calculating each order of the operating mode of the wind turbine generator set under natural excitation; and issuing a fault warning when the deviation between the measured modal frequency of a certain order and the operating frequency of the wind turbine generator set is within 10%.

[0004] The above-mentioned related technical scheme realizes the monitoring of the wind turbine generator set by monitoring the vibration signal of the wind turbine generator. However, when the breeze generator set is running, based on the operating characteristics of the breeze generator set, when the breeze generator set fails, its vibration amplitude is small and difficult to measure, resulting in low accuracy of the monitoring result. In addition, the breeze generator set does not always generate vibration when it fails. The breeze generator set will only generate vibration when the shaft and bearing are abnormal. When the internal circuit components are aged or fail, the breeze generator set will not generate vibration. Therefore, relying on monitoring the vibration signal to monitor the breeze generator set results in low accuracy of the monitoring result, which cannot accurately reflect the operating status of the breeze generator set. Summary of the invention

[0005] In order to solve the problem in the prior art that the accuracy of monitoring results of micro-wind generator sets is low due to monitoring micro-wind generator sets through vibration signals, the present invention provides a method and system for automatically protecting micro-wind generator sets.

[0006] In a first aspect, the present invention provides a method for automatically protecting a micro-wind generator set, which adopts the following technical solution: Obtain the parameters of each breeze generator set at each time, as well as the parameters of the reference generator set at each time, the parameters including wind speed, rotation speed and output power; The breeze generator set to be detected is taken as the target breeze generator set, and any breeze generator set is selected as the reference generator set of the target breeze generator set; Divide the multiple moments into multiple time periods, draw a first curve about wind speed and output power of the target breeze generator set in each time period, and draw a second curve about wind speed and output power of the reference generator set in each time period; Constructing a fault evaluation function of the target micro-wind generator set, obtaining a maximum value of the fault evaluation value according to the fault evaluation function, and issuing an early warning prompt in response to the maximum value being greater than a preset threshold value; Among them, the expression of the fault evaluation function is:

[0007] Where w represents the fault evaluation value of the target wind turbine generator set, , , represents the wind speed corresponding to the first, kth and ath data points, k represents the kth data point, a represents the total number of data points, g(n) is the first curve of the target breeze generator set in the time period, The second curve of the reference generator set during the time period, tanh represents the normalized function, and n represents the wind speed.

[0008] By selecting a reference generator set, comparing the target breeze generator set with the reference generator set, and constructing a fault evaluation function, the breeze generator set can be accurately monitored, effectively avoiding further acceleration of the fault of the reference generator set, realizing automatic protection of the breeze generator set, and improving the accuracy of the monitoring results.

[0009] Preferably, the method for selecting the reference generator set is: Obtain the speed of each breeze generator set at different times within a time period, and construct a speed sequence based on the obtained multiple speeds; Calculate the reference coefficient between the target micro-wind generator set and each of the remaining micro-wind generator sets; The micro-wind generator set corresponding to the maximum value of the reference coefficient is used as the reference generator set of the target micro-wind generator set in the corresponding time period; The expression of the reference coefficient is:

[0010] In the formula, is the reference coefficient, is the speed sequence of the target breeze generator set from the i-th to the j-th moment in the time period, is the speed sequence of the other breeze generator set from the i-th to the j-th moment in the time period, mean is the mean function, and PPMCC is the Pearson correlation coefficient.

[0011] By calculating the reference coefficient and using it to select the reference generator set, the similarity between the reference generator set and the target wind generator set is quantified, and the accuracy of the reference generator set selection is improved.

[0012] Preferably, the method for selecting the reference generator set is: The distance between each breeze generator set and the target breeze generator set is calculated, and the breeze generator set corresponding to the minimum value is used as the reference generator set.

[0013] Preferably, the method of dividing multiple moments into multiple time periods is: The wind speeds at each moment are sorted in chronological order, and the wind speed samples are clustered in an ordered manner to obtain multiple clusters, and the data points in each cluster correspond to a time period.

[0014] Classifying each moment into multiple time periods facilitates analysis of data within the time period and improves the accuracy of data analysis.

[0015] Preferably, the method for drawing the first curve of wind speed and output power of the target breeze generator set in each time period is: constructing a three-dimensional coordinate system with wind speed as the x-axis, time as the y-axis, and output power as the z-axis, mapping the parameters into the three-dimensional coordinate system, projecting the parameters into the plane formed by the x-axis and the z-axis to obtain multiple data points, and fitting the multiple data points to obtain the first curve.

[0016] By fitting the data points to obtain the first curve, it is convenient to analyze the parameters and understand the operation status of the breeze generator set.

[0017] Preferably, the first curve is obtained by fitting multiple data points using a spline curve fitting method or a least squares method.

[0018] Preferably, the method further comprises: Calculate the fault deepening speed of the target wind turbine generator set, the expression is:

[0019] Where u is the fault deepening speed, g(n) is the first curve of the target wind turbine generator set in the time period, is the second curve of the reference generator set in the time period, Indicates The wind speed corresponding to the data point is Indicates The wind speed corresponding to the data point, n represents the wind speed.

[0020] By calculating the fault deepening speed, we can understand the trend of fault acceleration, take corresponding measures to the breeze generator set in time according to the trend of fault acceleration, and effectively protect the breeze generator set.

[0021] In a second aspect, the present invention provides an automatic protection system for a micro-wind generator set, which adopts the following technical solution: A micro-wind generator set automatic protection system comprises: a processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, the micro-wind generator set automatic protection method described above is implemented.

[0022] The present invention has the following technical effects: By selecting a reference generator set, comparing the target breeze generator set with the reference generator set, and constructing a fault evaluation function, the breeze generator set can be accurately monitored, effectively avoiding further acceleration of the fault of the reference generator set, realizing automatic protection of the breeze generator set, and improving the accuracy of the monitoring results. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] By reading the detailed description below with reference to the accompanying drawings, the above and other purposes, features and advantages of the exemplary embodiments of the present invention will become readily understood. In the accompanying drawings, several embodiments of the present invention are shown in an exemplary and non-restrictive manner, and the same or corresponding reference numerals represent the same or corresponding parts.

[0024] Figure 1 The present invention is a flow chart of a method for automatically protecting a micro-wind generator set. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are 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 those skilled in the art without creative work are within the scope of protection of the present invention.

[0026] It should be understood that when the terms "first", "second", etc. are used in the claims, descriptions, and drawings of the present invention, they are only used to distinguish different objects, rather than to describe a specific order. The terms "include" and "comprise" used in the description and claims of the present invention indicate the presence of the described features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their collections.

[0027] The embodiment of the present invention discloses a method for automatically protecting a micro-wind generator set, referring to Figure 1 , including the following steps: S1: Obtain the parameters of each breeze generator set at each time, as well as the parameters of the reference generator set at each time, the parameters including wind speed, rotation speed and output power; For each breeze generator set in the area, each moment corresponds to a wind speed data, a shaft speed data and an output power data of the breeze generator set, and the data collection interval is 5 seconds, so as to further obtain parameters at multiple moments.

[0028] S2: The micro-wind generator set to be detected is taken as the target micro-wind generator set, and any micro-wind generator set is selected as the reference generator set of the target micro-wind generator set.

[0029] In one embodiment, a method for selecting a reference generator set is as follows: obtaining the rotational speed of each breeze generator set at different times within a time period, and constructing a rotational speed sequence based on the multiple rotational speeds obtained; calculating a reference coefficient of the target breeze generator set and each of the remaining breeze generator sets; and taking the breeze generator set corresponding to the maximum value of the reference coefficient as the reference generator set of the target breeze generator set within the corresponding time period.

[0030] The expression of the reference coefficient is:

[0031] In the formula, is the reference coefficient, is the speed sequence of the target breeze generator set from the i-th to the j-th moment in the time period, is the speed sequence of the other breeze generator set from the i-th to the j-th moment in the time period, mean is the mean function, and PPMCC is the Pearson correlation coefficient.

[0032] in, It indicates the average similarity of the rotation speeds of the two wind turbines. The larger the value, the more similar the rotation speeds of the two wind turbines are. It indicates the overall similarity of the rotational speeds of the two breeze generator sets. The larger the value, the more similar the rotational speeds of the two breeze generator sets are as a whole. Therefore, the larger the reference coefficient, the more similar the rotational speeds of the two breeze generator sets are.

[0033] In a group of breeze generators, each breeze generator is located in a different spatial position, so the impact of wind force on each breeze generator will also vary. Therefore, a breeze generator with similar force conditions to the target breeze generator is found as a reference generator within a certain period of time. The speed can be used to measure the degree of wind force impact on the breeze generator. When the speeds of two breeze generators are similar, the impact of wind force on them is also similar. It can be understood that the larger the reference coefficient, the more similar the speeds of the two breeze generators are, and the more similar the impact of wind force on the two breeze generators is.

[0034] Exemplarily, there are four groups of breeze generator sets a, b, c, and d. Breeze generator set a is taken as the target breeze generator set. The reference coefficient between group a and group b is 0.75, the reference coefficient between group a and group c is 0.82, and the reference coefficient between group a and group d is 0.78. Among them, the reference coefficient between group a and group c is the largest, so group c is taken as the reference generator set for group a.

[0035] In one embodiment, in the micro-wind generator group, the two micro-wind generators closest to each other are similarly affected by wind force, so the micro-wind generator closest to the target micro-wind generator is used as the reference generator.

[0036] S3: Divide the multiple moments into multiple time periods, draw a first curve of wind speed and output power of the target breeze generator set in each time period, and a second curve of wind speed and output power of the reference generator set in each time period.

[0037] In a day, the wind speed in different time periods is different. Therefore, multiple moments are divided into multiple time periods according to the wind speed. The division method is: sort the wind speed at each moment in chronological order, and perform ordered sample clustering of the wind speed to obtain multiple clusters. Each cluster has multiple wind speed data, and each data point in the cluster corresponds to a time period.

[0038] The method for drawing the first curve of wind speed and output power of the target breeze generator set in each time period is as follows: construct a three-dimensional coordinate system with wind speed as the x-axis, time as the y-axis, and output power as the z-axis, map the parameters into the three-dimensional coordinate system, project the parameters into the plane formed by the x-axis and the z-axis to obtain multiple data points, and use the spline curve fitting method or the least squares method to fit the multiple data points to obtain the first curve. It can be seen that the first curve reflects the relationship between the wind speed and the output power of the target breeze generator set.

[0039] Similarly, a second curve is drawn about the wind speed and the output power of the reference generator set in each time period, and the second curve reflects the relationship between the wind speed and the output power of the reference generator set.

[0040] S4: constructing a fault evaluation function of the target micro-wind generator set, obtaining a maximum value of the fault evaluation value according to the fault evaluation function, and issuing an early warning in response to the maximum value being greater than a preset threshold.

[0041] The expression of the fault evaluation function is:

[0042] Where w represents the fault evaluation value of the target wind turbine generator set, , , They represent the wind speeds corresponding to the first, kth and ath data points respectively, k represents the kth data point, a represents the total number of data points (the total number of data points in the first curve or the second curve), g(n) is the first curve of the target breeze generator set within the time period, The second curve of the reference generator set during the time period, tanh represents the normalized function, and n represents the wind speed.

[0043] in, Indicates wind speed arrive When , the difference between the target wind turbine generator set and the reference turbine generator set in performance is greater, the greater the difference between the two. Similarly, Indicates wind speed arrive When , the difference in performance between the target breeze generator set and the reference generator set is greater, the greater the difference between the two. The difference here can be understood as the difference in the power generation capacity of the breeze generator set. During the operation of the breeze generator set, the target breeze generator set and the reference generator set are similarly affected by wind force. Therefore, under normal circumstances, the output power of the target breeze generator set and the reference generator set should also be similar. In other words, under normal circumstances, the first curve is similar to the second curve, and the difference is small; on the contrary, when the target breeze generator set fails, the output power difference between the target breeze generator set and the reference generator set is large, and the corresponding difference between the first curve and the second curve is also large.

[0044] In the first curve and the second curve, different wind speeds are iteratively selected to obtain different fault evaluation values. When the maximum value of the fault evaluation value is greater than the preset threshold, it indicates that a fault has occurred in the target micro-wind generator set and the target micro-wind generator set needs to be repaired in time. At the same time, the wind speed corresponding to the kth data point (the data point in the first curve) when the fault evaluation value is the maximum value is calculated. The value of is taken as the fault node, and the fault node indicates that the target micro wind generator set has a When a fault occurs near the threshold, the threshold is set manually according to the actual situation. For example, the threshold is 0.5.

[0045] For example, in the current time period of the day, the 20th data point in the first curve The fault evaluation value of the target wind turbine generator set is 0.6, indicating that the target wind turbine generator set has a fault in the current time period. The interval (6.5, 7.0) is constructed as the center, and the parameters of the wind speed in the interval (6.5, 7.0) are found within the time period. If the wind speed at the 50th, 60th and 65th moments in this time period is within the interval, it indicates that the target breeze generator set has a fault at the 50th, 60th or 65th moment. At this time, the 50th moment is taken as the time point corresponding to the fault node.

[0046] S5: Calculate the fault deepening speed of the target wind turbine generator set.

[0047] The expression of fault deepening speed is:

[0048] Where u is the fault deepening speed, g(n) is the first curve of the target wind turbine generator set in the time period, is the second curve of the reference generator set in the time period, Indicates The wind speed corresponding to the data points (the data points in the first curve), Indicates The wind speed corresponding to the data points (the data points in the first curve), n represents the wind speed.

[0049] The fault deepening speed indicates the speed at which the target breeze generator set is damaged. The larger the value, the faster the target breeze generator set is damaged. When the fault deepening speed is greater than the preset deepening threshold, it indicates that the target breeze generator set is in a state of rapid damage. During the calculation process, the value of L is iteratively selected from small to large.

[0050] For example, in the current time period of a day, the target breeze generator set is at the 50th moment (corresponding to the 20th data point in the first curve) ) a fault occurs, and the fault deepening speed at the 30th data point in the first curve is greater than the preset threshold, that is, The fault deepening speed at the point is greater than the preset threshold. The time point corresponding to the wind speed is the 100th moment, indicating that the target breeze generator set is accelerating damage at the 100th moment. At this time, the target breeze generator set is stopped before the 100th + (100-50) = 150th moment to avoid damage caused by continued operation of the target breeze generator set. It is understandable that correspond , correspond , correspond .

[0051] The embodiment of the present invention further discloses an automatic protection system for a micro-wind generator set, including a processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, an automatic protection method for a micro-wind generator set according to the present invention is implemented.

[0052] The above system also includes other components well known to those skilled in the art, such as a communication bus and a communication interface, and their configuration and functions are known in the art, so they will not be described in detail here.

[0053] In the present invention, the aforementioned memory may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system, apparatus or device. For example, a computer-readable storage medium may be any appropriate magnetic storage medium or magneto-optical storage medium, such as a resistive random access memory RRAM (Resistive Random Access Memory), a dynamic random access memory DRAM (Dynamic Random Access Memory), a static random access memory SRAM (Static Random Access Memory), an enhanced dynamic random access memory EDRAM (Enhanced Dynamic Random Access Memory), a high bandwidth memory HBM (High Bandwidth Memory), a hybrid memory cube HMC (Hybrid Memory Cube), etc., or any other medium that can be used to store the required information and can be accessed by an application, a module or both. Any such computer storage medium may be part of a device or accessible or connectable to a device.

[0054] Although this specification has shown and described a number of embodiments of the present invention, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Those skilled in the art will conceive of many modifications, changes and alternatives without departing from the ideas and spirit of the present invention. It should be understood that in the practice of the present invention, various alternatives to the embodiments of the present invention described herein may be employed.

[0055] The above are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for automatically protecting a micro-wind generator set, characterized in that: Includes steps: Obtain the parameters of each breeze generator set at each time, as well as the parameters of the reference generator set at each time, the parameters including wind speed, rotation speed and output power; The breeze generator set to be detected is taken as the target breeze generator set, and any breeze generator set is selected as the reference generator set of the target breeze generator set; Divide the multiple moments into multiple time periods, draw a first curve about wind speed and output power of the target breeze generator set in each time period, and draw a second curve about wind speed and output power of the reference generator set in each time period; Constructing a fault evaluation function of the target micro-wind generator set, obtaining a maximum value of the fault evaluation value according to the fault evaluation function, and issuing an early warning prompt in response to the maximum value being greater than a preset threshold value; Among them, the expression of the fault evaluation function is: Where w represents the fault evaluation value of the target wind turbine generator set, , , represents the wind speed corresponding to the first, kth and ath data points, k represents the kth data point, a represents the total number of data points, g(n) is the first curve of the target breeze generator set in the time period, The second curve of the reference generator set during the time period, tanh represents the normalized function, and n represents the wind speed.

2. The method for automatically protecting a micro-wind generator set according to claim 1, characterized in that: The selection method of the reference generator set is: Obtain the speed of each breeze generator set at different times within a time period, and construct a speed sequence based on the obtained multiple speeds; Calculate the reference coefficient between the target micro-wind generator set and each of the remaining micro-wind generator sets; The micro-wind generator set corresponding to the maximum value of the reference coefficient is used as the reference generator set of the target micro-wind generator set in the corresponding time period; The expression of the reference coefficient is: In the formula, is the reference coefficient, is the speed sequence of the target breeze generator set from the i-th to the j-th moment in the time period, is the speed sequence of the other breeze generator set from the i-th to the j-th moment in the time period, mean is the mean function, and PPMCC is the Pearson correlation coefficient.

3. The method for automatically protecting a micro-wind generator set according to claim 1, characterized in that: The selection method of the reference generator set is: The distance between each breeze generator set and the target breeze generator set is calculated, and the breeze generator set corresponding to the minimum value is used as the reference generator set.

4. The method for automatically protecting a micro-wind generator set according to claim 1, characterized in that: The method of dividing multiple moments into multiple time periods is: The wind speeds at each moment are sorted in chronological order, and the wind speed samples are clustered in an ordered manner to obtain multiple clusters, and the data points in each cluster correspond to a time period.

5. The method for automatically protecting a micro-wind generator set according to claim 1, characterized in that: The method for drawing the first curve of wind speed and output power of the target breeze generator set in each time period is as follows: construct a three-dimensional coordinate system with wind speed as the x-axis, time as the y-axis, and output power as the z-axis, map the parameters into the three-dimensional coordinate system, project the parameters into the plane formed by the x-axis and the z-axis to obtain multiple data points, and fit the multiple data points to obtain the first curve.

6. The method for automatically protecting a micro-wind generator set according to claim 1, characterized in that: A first curve is obtained by fitting multiple data points using a spline curve fitting method or a least squares method.

7. The method for automatically protecting a micro-wind generator set according to claim 1, characterized in that: The method also includes: Calculate the fault deepening speed of the target wind turbine generator set, the expression is: Where u is the fault deepening speed, g(n) is the first curve of the target wind turbine generator set in the time period, is the second curve of the reference generator set in the time period, Indicates The wind speed corresponding to the data point is Indicates The wind speed corresponding to the data point, n represents the wind speed.

8. An automatic protection system for a micro-wind generator set, characterized in that: include: A processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, an automatic protection method for a micro wind generator set according to any one of claims 1 to 7 is implemented.

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