An elevator energy feedback device operation state visualized monitoring method and system

Abstract

The present application belongs to the technical field of image data processing, and particularly relates to a kind of elevator energy feedback device operating state visual monitoring method and system, its method includes: obtaining infrared thermal image and total regenerative power at each moment;Infrared thermal image is detected, cluster analysis and line angle judgment are carried out, and brake resistance fin area is obtained;According to the distribution difference of average temperature in brake resistance fin area corresponding to each moment and other moments in its reference period, the energy overflow index of each moment is determined, and the energy overflow index is corrected in combination with the change of total regenerative power;Based on the health period and dynamic threshold updated adaptively based on the corrected energy overflow index, the accurate monitoring of device operating state is realized.The present application can effectively distinguish normal temperature rise and abnormal heating, and significantly reduce the false alarm rate.

Description

Technical Field

[0001] This invention relates to the field of image data processing technology. More specifically, this invention relates to a method and system for visually monitoring the operating status of an elevator energy feedback device. Background Technology

[0002] With the popularization of green building concepts, elevator energy feedback technology has become a key energy-saving measure. When the elevator is heavily loaded and going downhill or lightly loaded and going uphill, the regenerative electrical energy generated by its motor is recovered by the energy feedback device and fed back to other electrical equipment. This replaces the traditional method of using braking resistors to dissipate heat energy, which not only reduces energy waste but also significantly reduces the temperature of the machine room and protects the working environment of the equipment in the machine room. To ensure the reliability of the energy feedback device, its operating status needs to be visualized and monitored.

[0003] Traditional methods for monitoring the operating status of elevator energy feedback devices often involve setting a fixed temperature threshold. However, in reality, the energy feedback device and the braking resistor are connected in parallel in the circuit, jointly handling the regenerated electrical energy. When the energy feedback device experiences a decrease in efficiency, the overflowing energy that it cannot process will naturally flow to the braking resistor, causing it to heat up.

[0004] Existing fixed-threshold monitoring methods cannot distinguish between normal temperature rise of equipment in the computer room under high-power operation and abnormal heating caused by decreased operating efficiency of energy feedback devices. This leads to frequent false alarms and makes it impossible to accurately assess the true health status of energy feedback devices. This not only wastes maintenance resources but also causes elevators to stop due to frequent preventative maintenance, directly affecting the normal passage of users in the building and reducing user satisfaction. Therefore, how to effectively distinguish between normal temperature rise and abnormal heating is the core technical problem for achieving operational status assessment. Summary of the Invention

[0005] To address the technical problem of inaccurate monitoring results caused by the inability of traditional fixed threshold monitoring methods to distinguish between normal temperature rise and abnormal heating, this invention provides solutions in the following aspects.

[0006] In a first aspect, the present invention provides a method for visually monitoring the operating status of an elevator energy feedback device, comprising: acquiring an infrared thermal image and total regenerative power at each moment; extracting all straight lines from the infrared thermal image at each moment; performing angle statistics, cluster analysis, and line angle judgment on all straight lines to obtain the straight lines constituting the outer envelope of the braking resistor heat sink area; determining the energy overflow index at each moment based on the difference in average temperature distribution within the braking resistor heat sink area at each moment and other moments within a reference time period; constructing a first sequence and a second sequence at each moment using the total regenerative power and energy overflow index at all moments within the reference time period; correcting the energy overflow index at each moment based on the change in total regenerative power at each moment compared to the previous moment and the correlation coefficient between the first sequence and the second sequence, and determining the corrected energy overflow index at each moment; using the reference time period at the first moment as the initial healthy time period, calculating the energy overflow index threshold at the first moment based on the corrected energy overflow index at all moments within the initial healthy time period; for each subsequent moment, dynamically updating the healthy time period and recalculating the energy overflow index threshold for judging the operating status at the next moment based on the relationship between the corrected energy overflow index at each moment and the energy overflow index threshold at the previous moment, thereby realizing operating status monitoring.

[0007] This invention achieves precise monitoring of energy feedback devices through multi-step collaboration; by utilizing the geometric characteristics of the braking resistor heat sink area, a straight line constituting the outer envelope of this area is obtained, ensuring the consistency of the temperature data source; through time-series temperature trend analysis, progressive faults are sensitively captured; further, regenerative power is introduced for dual dynamic correction, effectively eliminating normal thermal interference under high load; finally, an adaptive dynamic threshold is used to complete anomaly judgment, forming a complete closed loop from data acquisition and processing to intelligent evaluation, significantly improving the automation level of monitoring and the reliability of early warning.

[0008] Preferably, the method for obtaining all straight lines in the infrared thermal image at each moment is as follows: Canny edge detection is performed on the infrared thermal grayscale image at each moment to obtain the edge binary image at each moment, wherein white pixels are pixels belonging to the edge; Hough line detection is performed on the white pixels in the edge binary image at each moment.

[0009] Preferably, the step of performing angle statistics, cluster analysis, and line angle judgment on all straight lines to obtain the straight lines constituting the outer envelope of the braking resistor heat sink region includes: obtaining the angles and pixel counts of all straight lines in the coordinate system, constructing an angle statistics histogram and obtaining the peak angle, marking all straight lines corresponding to the peak angle as suspected heat sink straight lines; using the pixel counts of all suspected heat sink straight lines as clustering samples, performing clustering using the DBSCAN clustering algorithm, obtaining the clustering results, and taking the cluster with the most straight lines in the cluster as the braking resistor heat sink region cluster; extracting the two straight lines with the maximum vertical distance between any two straight lines in the region cluster as two edge lines, and obtaining the four endpoints of the two edge lines; judging the angle between the endpoints to obtain the straight lines constituting the outer envelope of the braking resistor heat sink region.

[0010] Preferably, the determination of the included angle of the endpoint connection lines to obtain the straight line forming the outer envelope of the braking resistor heat sink area includes: for each endpoint of any edge line, obtaining two lines connecting it to the two endpoints of another edge line; using the formula for calculating the included angle between the two lines, obtaining the included angle between any edge line and the two lines, and taking the line corresponding to the maximum value of the included angle as a side line, thus obtaining two side lines; and combining the two side lines and the two straight lines to form the outer envelope of the braking resistor heat sink area.

[0011] This invention achieves automatic positioning of the braking resistor heat sink area in complex computer room thermal environments through straight line detection, cluster analysis, and connection angle judgment, effectively avoiding interference from heat sources in other areas.

[0012] Preferably, the energy overflow exponent at each moment satisfies the expression: In the formula, For the first Energy overflow index at a given moment; For the first The average temperature within the heat sink area of ​​the braking resistor at each moment; For the first Within the reference time period of the nth moment, the nth The average temperature within the heat sink area of ​​the braking resistor at other times; For the first The index value and total number of all other times within the reference time period of the given time; For the first Within the reference time period of the nth moment, the nth Other moments and the first The time interval between each moment; For the first Within the reference time period of the first moment, all other moments are related to the first moment. The maximum value among the time intervals at each moment; It is the tangent function of a hyperbola.

[0013] This invention introduces a time decay weighting factor, which makes the contribution of recent temperature changes to the results greater than that of long-term changes, thereby capturing the continuous and weak temperature rise trend in the early stage of a fault, improving the detection rate of early faults, and providing a time window for preventive maintenance.

[0014] Preferably, the corrected energy spillover exponent at each time step satisfies the expression: In the formula, For the first Energy overflow index corrected at each moment; For the first Energy overflow index at a given moment; For the first The moment and the Total regenerative power at any given moment; For the first The correlation coefficient between the first and second sequences at each time point; It is a natural exponential function; This is the standard normalization function.

[0015] This invention integrates two dimensions: the correlation between data in a recent period and the instantaneous power change trend. It can distinguish between abnormal heating caused by real faults and normal temperature rise caused by high load conditions, thus solving the problem of false alarms caused by the inability of traditional methods to distinguish heat sources.

[0016] Preferably, the correlation coefficient is obtained using the Pearson correlation coefficient.

[0017] Preferably, the energy spillover index threshold is calculated using the 3-Sigma principle.

[0018] Preferably, the dynamic update of the health time period includes: recording the previous moment as... Record the next moment as Using the energy overflow exponential threshold from the previous moment Determine the energy overflow index after the next moment. Is it abnormal: If If it is judged to be normal, the next time step is added to the healthy time period updated from the previous time step to obtain the healthy time period updated from the next time step; if If it is judged as abnormal, the healthy time period updated in the previous moment will be used as the healthy time period updated in the next moment.

[0019] This invention achieves dynamic updates of healthy periods by evaluating the changing characteristics of the corrected energy overflow index in real time, ensuring that the data during healthy periods is not contaminated by abnormal data when calculating the adaptive threshold, thereby maintaining a high sensitivity to real faults.

[0020] Secondly, the present invention provides a visual monitoring system for the operation status of an elevator energy feedback device, comprising a processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, the aforementioned method for visual monitoring the operation status of an elevator energy feedback device is implemented.

[0021] By adopting the above technical solution, a computer program is generated from the above-mentioned method for visually monitoring the operating status of an elevator energy feedback device, and stored in a memory so that it can be loaded and executed by a processor. This allows for the creation of a terminal device based on the memory and processor, making it convenient to use.

[0022] The beneficial effects of this invention are as follows:

[0023] (1) The present invention uses the inherent linear array geometric prior features of the braking resistor heat sink to locate its heat sink area, thus ensuring the consistency of the source of the analysis data;

[0024] (2) Based on the dual correction mechanism of real-time regeneration power, the present invention solves the interference of normal temperature rise under high load and provides accurate data support for subsequent anomaly identification;

[0025] (3) This invention abandons the traditional fixed threshold and calculates the statistical threshold by dynamically maintaining the health period at each time, which significantly reduces the false alarm rate. Attached Figure Description

[0026] Figure 1 This is a flowchart illustrating a method for visually monitoring the operating status of an elevator energy feedback device according to the present invention;

[0027] Figure 2 This is a schematic representation of an infrared thermal imaging grayscale image of the computer room area;

[0028] Figure 3 This is a schematic diagram showing the angle statistical histogram corresponding to the infrared thermal imaging grayscale image of the computer room area;

[0029] Figure 4 This is a schematic diagram showing the division of the braking resistor heat sink area in the infrared thermal imaging grayscale image of the computer room area;

[0030] Figure 5 This is a schematic diagram showing the changes in the average temperature within the heat sink area of ​​the braking resistor and the total regenerative power of the energy feedback device itself.

[0031] Figure 6 This is a schematic visualization showing the operating status of the elevator energy feedback device. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0034] This invention discloses a method for visually monitoring the operating status of an elevator energy feedback device, referring to... Figure 1 This includes steps S1-S5:

[0035] S1. Obtain the infrared thermal image at each moment.

[0036] It should be noted that the main function of the energy feedback device is to replace the traditional method of using braking resistors to dissipate heat. Therefore, the operating status of the energy feedback device can be analyzed by real-time monitoring of the thermal imaging map in the computer room to determine whether there is significant heat dissipation in the braking resistor area, thus providing data for assessing the operating status of the energy feedback device.

[0037] Specifically, an infrared thermal imager is deployed in the elevator machine room to ensure that its field of view can completely cover the entire area of ​​the braking resistor; the preset acquisition frequency is once per second to collect infrared thermal images of the machine room area in real time and obtain the temperature value corresponding to each pixel.

[0038] At this point, infrared thermal images of each moment have been obtained.

[0039] S2. Extract all straight lines from the infrared thermal image at each moment; perform angle statistics, cluster analysis, and line angle judgment on all straight lines to obtain the straight lines that make up the outer envelope of the braking resistor heat sink area;

[0040] It should be noted that since the actual energy feedback device and the braking resistor are connected in parallel in the circuit, when the energy feedback device is not operating well, the overflowing energy that cannot be handled will naturally flow to the braking resistor, causing the braking resistor area to heat up. Therefore, it is necessary to first delineate the corresponding braking resistor area in the infrared thermal image to provide accurate data for subsequent thermal analysis. Considering the function of the braking resistor, its device often has neatly arranged heat sinks, so the braking resistor area in the infrared thermal image is delineated based on this geometric feature.

[0041] Specifically, the infrared thermal image at each moment is converted into a grayscale image. The pixel at the bottom left corner of the grayscale image is taken as the origin, and the horizontal direction to the right from the origin is used as... The positive direction of the axis is defined by taking the vertically upward direction from the origin as... The positive direction of the axis is used to construct a Cartesian coordinate system. The Canny edge detection algorithm is used to perform edge detection on the grayscale image at each time step to obtain the edge binary image at each time step, where white pixels belong to the edge and black pixels belong to the background. The Hough line detection algorithm is used to detect lines on the white pixels in the edge binary image at each time step, obtaining the angle of each line in the coordinate system and the number of pixels of each line. It should be noted that the Canny edge detection and Hough line detection algorithms are well-known technologies and will not be described in detail here.

[0042] For the angles of all straight lines in the coordinate system, construct an angle statistical histogram and obtain the peak angle; extract all straight lines corresponding to the peak angle and mark them as suspected heat sink straight lines.

[0043] For example, targeting Figure 2 The infrared thermal imaging grayscale image of the computer room area shown is illustrated in the following figure, along with its corresponding angle statistical histogram. Figure 3 As shown, the horizontal axis represents the angle of the line in the coordinate system, the vertical axis represents the number of lines detected, and the height of the blue bars represents the number of lines detected for each angle. Figure 3 As shown in the figure, the peak value is concentrated at 90.5°, indicating that the heat sink of the braking resistor in the computer room area is mainly vertical, which is consistent with the geometric characteristics of the braking resistor heat sink in the computer room area.

[0044] The number of pixels with the most straight lines in all suspected heat sinks is used as the clustering sample. The DBSCAN clustering algorithm is used to perform clustering, and the cluster with the most straight lines is taken as the heat sink region cluster of the braking resistor.

[0045] Two lines with the maximum vertical distance between any two lines within the braking resistor heat sink area cluster are extracted as two edge lines, and the four endpoints of the two edge lines are obtained. These form the outer envelope of the braking resistor heat sink area. Specifically, for any endpoint of any edge line, two lines are obtained connecting it to the two endpoints of another edge line. The angle between any edge line and the two connecting lines is calculated using the formula for the angle between the two lines, and the line corresponding to the maximum value of the angle is taken as the first side line. Similarly, the same operation is performed on the other endpoint to obtain the second side line. The two side lines and the two lines together form the outer envelope of the braking resistor heat sink area.

[0046] At this point, the corresponding area of ​​the braking resistor heat sink at each moment has been obtained.

[0047] For example, Figure 4This is a diagram showing the division of the braking resistor heatsink area in the infrared thermal imaging grayscale image of the computer room area. Two red lines represent two edge lines, two blue lines represent two side lines, and four light blue circles represent the four endpoints of the two edge lines, labeled 1, 2, 3, and 4. For endpoint 1, the angle between the edge line corresponding to endpoint 1 and the line connecting endpoints 1 and 3 is 87.5°, and the angle between the edge line corresponding to endpoint 1 and the line connecting endpoints 1 and 4 is 38.9°. Therefore, the line connecting endpoints 1 and 3 is selected as the first side line. For endpoint 2, the angle between the edge line corresponding to endpoint 2 and the line connecting endpoints 2 and 3 is 41.3°, and the angle between the edge line corresponding to endpoint 1 and the line connecting endpoints 2 and 4 is 91.8°. Therefore, the line connecting endpoints 2 and 4 is selected as the second side line. This ensures that the outer envelope encompasses the entire braking resistor heatsink area.

[0048] S3. Determine the energy overflow index for each moment based on the difference in average temperature distribution within the heat sink area of ​​the braking resistor corresponding to each moment and other moments in the reference period.

[0049] It should be noted that in actual working conditions, when the elevator energy feedback device is not operating well, its efficiency may gradually decrease, causing some of the regenerated energy to fail to be effectively fed back to the grid, but instead overflows and flows to the parallel braking resistor, causing it to gradually heat up. This heating trend is often a gradual process. Therefore, by analyzing the change in the average temperature of the braking resistor heat sink area at each moment relative to its recent historical temperature distribution, the energy overflow index of the energy feedback device at each moment can be dynamically evaluated, thereby reflecting whether the energy feedback device has a problem of low operating efficiency.

[0050] Specifically, a reference time period is established for each moment, where each moment is the last moment within that reference time period; the preset length of the reference time period is [missing information]. , The preset length defines the time scale for analyzing the average temperature change within the heat sink area of ​​the braking resistor over a short period. The window needs to be able to analyze recent data; therefore, the preset length needs to be greater than 10 to ensure that recent average temperature change trends can be captured. This invention uses the preset length... The value is set to 30. It should be noted that for the time period [0,30], due to insufficient historical data, it is impossible to obtain a complete reference time period of length 30. Therefore, in the case where the reference time period of a moment is incomplete, the data of this moment is used to fill in the missing moment data.

[0051] Calculate the average temperature within the heat sink area of ​​the braking resistor at each time moment. This average temperature is equal to the average temperature value of all pixels within the corresponding heat sink area in the infrared thermal image at each time moment. Determine the energy overflow index for each time moment based on the difference in average temperature distribution within the heat sink area at each time moment compared to other times within a reference time period. The energy overflow index satisfies the following expression:

[0052]

[0053] In the formula, For the first Energy overflow index at a given moment; For the first The average temperature within the heat sink area of ​​the braking resistor at each moment; For the first Within the reference time period of the nth moment, the nth The average temperature within the heat sink area of ​​the braking resistor at other times; For the first The index value and total number of all other times within the reference time period of the given time; For the first Within the reference time period of the nth moment, the nth Other moments and the first The time interval between each moment; For the first Within the reference time period of the first moment, all other moments are related to the first moment. The maximum value among the time intervals at each moment; It is the tangent function of a hyperbola.

[0054] in, Reflecting the The time period relative to the reference time period, the first The relative differences in the average temperature of the braking resistor heatsink area at other times; considering that recent changes often better reflect potential problems when assessing equipment status, a weighting factor is introduced. , The smaller the value, the higher the number of reference points within the reference period. The closer another time is to the current time, the more it means that the first time within the reference period... The greater the weight of the temperature difference at other times in the energy spillover index, the more sensitively the spillover index can reflect the latest trend of heat increase in the braking resistor heatsink area. This is achieved by adjusting the weighting factor of each other time point within the reference period. The weighted average of the relative differences in the average temperature of the braking resistor heatsink area at a given moment relative to each other moment within the reference period effectively highlights the contribution of recent temperature changes to the energy overflow index. A larger value indicates a higher energy overflow index. The average temperature at a given moment is higher than at all other moments within the reference period and shows an upward trend, suggesting that the energy feedback device is in the first... The more significant the energy spillover at each moment, the better. It should be added that, through... The function will Value quantization in Within the range.

[0055] At this point, the energy overflow index at each moment has been obtained.

[0056] S4. Obtain the total regenerative power at each moment; correct the energy overflow index by using the changes in the total regenerative power and energy overflow index at all moments within the reference period at each moment, as well as the correlation coefficient between the first sequence and the second sequence, and determine the corrected energy overflow index at each moment.

[0057] It should be noted that, considering the high-frequency use of elevators during normal operating hours, the equipment in the machine room will also generate heat under high-intensity operation. This ambient temperature rise may contaminate the temperature reading of the braking resistor, making it appear as a slight upward trend. This behavior is similar to the abnormal heating caused by a malfunction in the energy feedback device, which means that relying solely on the current energy overflow index for assessment will result in a large number of false alarms, making it impossible to accurately assess the true health status of the energy feedback device. Therefore, it is also necessary to consider the regenerative power after processing by the energy feedback device, analyze the changes in the current total regenerative power, and correct the current energy overflow index to reduce false alarms.

[0058] Specifically, the total regenerative power at each moment is read synchronously and in real time from the data port of the energy feedback device itself. The total regenerative power refers to the power generated when the elevator motor works in reverse under the operation of the elevator energy feedback device, converting the potential and kinetic energy of the car and counterweight into electrical energy for use by other electrical equipment. Its unit is usually kilowatt. Due to the weight of the car and counterweight, the electrical energy converted by the elevator energy feedback device will not be 0 when the elevator is not working, that is, the minimum value of the total regenerative power is greater than 0.

[0059] Obtain the total regenerative power and energy spillover index for all times within the reference period at each time point, and construct a first sequence and a second sequence for each time point respectively; use the Pearson correlation coefficient to obtain the correlation coefficient between the first sequence and the second sequence at each time point.

[0060] The energy spillover index is corrected based on the change in total regenerative power at each time step compared to the previous time step and the correlation coefficient between the first and second sequences, thus determining the corrected energy spillover index at each time step; the corrected energy spillover index satisfies the expression:

[0061]

[0062] In the formula, For the first Energy overflow index corrected at each moment; For the first Energy overflow index at a given moment; For the first The moment and the Total regenerative power at any given moment; For the first The correlation coefficient between the first and second sequences at each time point; It is a natural exponential function; This is the standard normalization function.

[0063] in, Reflected in The linear correlation between the total regenerative power and the energy overflow index during a reference period at a given moment is considered. In a healthy feedback system, the energy feedback device effectively recovers energy, with no energy overflowing to the braking resistor or causing temperature contamination due to high-intensity operation. In this case, the temperature in the braking resistor area remains constant or slightly increases. That is, under normal circumstances, there is a positive correlation or no correlation between the regenerative power and the overflow index of the energy feedback device. However, since a fault can cause a significant decrease in regenerative power and an increase in overflow, therefore, through... Will The value is mapped to a new interval, when Approaching hour, Approaching ;when Approaching hour, Approaching ; The larger the value, the more significant the effect. There is a strong negative correlation between the regeneration power and the energy spillover index at time point 1, meaning that the energy feedback device at time point 2... There is a problem with the running status at a certain moment; Reflecting the The change in total regeneration power at each time point compared to the previous time point. Greater than 1 and The larger the value, the better the energy feedback device is in the first... The effective recovered energy at time is significantly lower than the effective recovered energy at the previous time, meaning that the energy feedback device at time is significantly lower than the effective recovered energy at the previous time. The greater the chance of energy overflow at any given moment; through As a correction term, the closer this value is to 1, the better the energy feedback device is in the first... The higher the probability of a problem at a given moment, the more likely the energy overflow index will remain unchanged; conversely, the closer the value is to 0, the more problematic the energy feedback device becomes at that moment. The lower the probability of a problem at any given moment, the lower the original energy overflow index needs to be to avoid false alarms.

[0064] At this point, the corrected energy overflow index for each moment has been obtained.

[0065] S5. Based on the health period and dynamic threshold that are adaptively updated according to the corrected energy overflow index, the operating status of the feedback device is monitored.

[0066] It should be noted that, considering the certain regularity of elevator usage, the corrected energy overflow index corresponding to the normal operation of the energy feedback device will be relatively concentrated, and anomalies that do not conform to these patterns will be statistically significantly deviated. However, if a fixed threshold is used to obtain the deviation point based on the data within the reference period at each moment, the processing effect for continuous abnormal data within the reference period is not good. Therefore, by constructing a period under relatively stable conditions in the early stage as the initial healthy reference period benchmark, the initial healthy reference period is dynamically updated using the statistical 3-Sigma principle to ensure that the corrected energy overflow index threshold within the healthy reference period at each moment is suitable for the data changes at each stage.

[0067] Specifically, the reference period at the first moment is used as the initial healthy period. The energy overflow index threshold at the first moment is calculated using the statistical 3-Sigma principle. The energy overflow index threshold at the first moment is obtained by taking the mean and standard deviation of the corrected energy overflow index at all moments within the initial healthy period. It should be noted that obtaining the threshold using the 3-Sigma principle is a well-known technique and will not be elaborated upon here.

[0068] Dynamically obtain the updated health time period at each subsequent moment and implement operational status monitoring. The specific method is as follows:

[0069] (1) Record the previous moment as Record the next moment as Using the energy overflow exponential threshold from the previous moment Determine the energy overflow index after the next moment. Is it abnormal: If This indicates that the energy feedback device is operating well in the next moment, so the next moment is added to the healthy time period updated from the previous moment to obtain the healthy time period updated from the next moment; if If the energy feedback device is inefficient or has other abnormal operating conditions at a later time, then the later time will be marked as an abnormal state, and the healthy time period updated at the previous time will be used as the healthy time period updated at the later time.

[0070] (2) Apply the 3-Sigma principle again to recalculate the energy overflow index threshold for the next time step within the health period after the update of the next time step, and apply it to the update and status monitoring of the next time step.

[0071] This completes the visualized monitoring of the elevator energy feedback device's operating status.

[0072] For example, in Figure 5 In the graph showing the changes in average temperature within the heatsink area of ​​the braking resistor and the total regenerative power of the energy feedback device, between 100 and 200 seconds, although the average temperature within the heatsink area of ​​the braking resistor increases, the total regenerative power of the energy feedback device also increases significantly, indicating that this stage may be a normal temperature rise caused by high load; while... Figure 6 In the visualization of the elevator energy feedback device's operating status, the energy overflow index is significantly different from the normal situation in the high load area. If the index is used directly for judgment, it will lead to a large number of false alarms. Through the correction process of the present invention S4, the corrected energy overflow index curve successfully suppresses the false peak in the high load area. When the real abnormality occurs after 200 seconds, the corrected energy overflow index rises rapidly and significantly, thereby accurately monitoring the abnormal operating status of the elevator energy feedback device.

[0073] This invention also discloses a visualization monitoring system for the operating status of an elevator energy feedback device, including a processor and a memory. The memory stores computer program instructions, and when the computer program instructions are executed by the processor, a visualization monitoring method for the operating status of an elevator energy feedback device according to the present invention is implemented.

[0074] The system also includes other components well known to those skilled in the art, such as communication buses and communication interfaces, the settings and functions of which are known in the art and will not be described in detail here.

Claims

1. A method for visually monitoring the operating status of an elevator energy feedback device, characterized in that, include: Acquire infrared thermal images and total regeneration power at each moment; Extract all straight lines from the infrared thermal image at each moment; perform angle statistics, cluster analysis, and line angle determination on all straight lines to obtain the straight lines that make up the outer envelope of the braking resistor heat sink area; The energy overflow index for each moment is determined based on the difference in the distribution of the average temperature within the heat sink area of ​​the braking resistor at each moment and at other moments in the reference period. By using the total regenerative power and energy spillover index of all times within the reference period at each time moment, a first sequence and a second sequence are constructed for each time moment; based on the change in total regenerative power at each time moment compared to the previous time moment and the correlation coefficient between the first sequence and the second sequence, the energy spillover index is corrected to determine the corrected energy spillover index at each time moment. The reference period of the first moment is used as the initial health period. Based on the energy overflow index corrected for all moments within the initial health period, the energy overflow index threshold for the first moment is calculated. For each subsequent moment, the health period is dynamically updated and the energy overflow index threshold used to determine the operating status of the next moment is recalculated based on the relationship between the corrected energy overflow index of each moment and the energy overflow index threshold of the previous moment, thereby realizing the monitoring of the operating status.

2. The method for visually monitoring the operating status of an elevator energy feedback device according to claim 1, characterized in that, The method for obtaining all straight lines in the infrared thermal image at each time moment is as follows: Canny edge detection is performed on the infrared thermal image grayscale image at each time moment to obtain the edge binary image at each time moment, where white pixels are pixels belonging to the edge; Hough line detection is performed on the white pixels in the edge binary image at each time moment.

3. The method for visually monitoring the operating status of an elevator energy feedback device according to claim 1, characterized in that, The step of performing angle statistics, cluster analysis, and line angle determination on all straight lines to obtain the straight lines that form the outer envelope of the braking resistor heat sink region includes: Obtain the angles and pixel counts of all straight lines in the coordinate system, construct an angle statistical histogram and obtain the peak angle, and mark all straight lines corresponding to the peak angle as suspected heat sink lines; use the pixel counts of all suspected heat sink lines as clustering samples, perform clustering using the DBSCAN clustering algorithm, obtain the clustering results, and take the cluster with the most straight lines in the cluster as the braking resistor heat sink region cluster; extract the two straight lines with the maximum vertical distance between any two straight lines in the region cluster as two edge lines, and obtain the four endpoints of the two edge lines; determine the included angle of the line connecting the endpoints to obtain the straight lines that form the outer envelope of the braking resistor heat sink region.

4. The method for visually monitoring the operating status of an elevator energy feedback device according to claim 3, characterized in that, The determination of the included angle between the endpoints to obtain the straight line forming the outer envelope of the braking resistor heat sink region includes: For each endpoint of any edge line, obtain two lines connecting it to the two endpoints of another edge line; use the formula for calculating the angle between two straight lines to obtain the angle between any edge line and the two connecting lines, and take the line corresponding to the maximum value of the angle as a side line to obtain two side lines; combine the two side lines and the two straight lines to form the outer envelope of the braking resistor heat sink area.

5. The method for visually monitoring the operating status of an elevator energy feedback device according to claim 1, characterized in that, The energy overflow index at each moment satisfies the expression: ； In the formula, For the first Energy overflow index at a given moment; For the first The average temperature within the heat sink area of ​​the braking resistor at each moment; For the first Within the reference time period of the nth moment, the nth The average temperature within the heat sink area of ​​the braking resistor at other times; For the first The index value and total number of all other times within the reference time period of the given time; For the first Within the reference time period of the nth moment, the nth Other moments and the first The time interval between each moment; For the first Within the reference time period of the first moment, all other moments are related to the first moment. The maximum value among the time intervals at each moment; It is the tangent function of a hyperbola.

6. The method for visually monitoring the operating status of an elevator energy feedback device according to claim 1, characterized in that, The corrected energy overflow exponent at each time moment satisfies the expression: ； In the formula, For the first Energy overflow index corrected at each moment; For the first Energy overflow index at a given moment; For the first The moment and the Total regenerative power at any given moment; For the first The correlation coefficient between the first and second sequences at each time point; It is a natural exponential function; This is the standard normalization function.

7. The method for visually monitoring the operating status of an elevator energy feedback device according to claim 6, characterized in that, The correlation coefficient was obtained using the Pearson correlation coefficient.

8. The method for visually monitoring the operating status of an elevator energy feedback device according to claim 1, characterized in that, The energy spillover index threshold is calculated using the 3-Sigma principle.

9. The method for visually monitoring the operating status of an elevator energy feedback device according to claim 1, characterized in that, The dynamically updated health time period includes: Let the previous moment be denoted as Record the next moment as Using the energy overflow exponential threshold from the previous moment Determine the energy overflow index after the next moment. Is it abnormal: If If it is judged to be normal, the next time step is added to the healthy time period updated from the previous time step to obtain the healthy time period updated from the next time step; if If it is judged as abnormal, the healthy time period updated in the previous moment will be used as the healthy time period updated in the next moment.

10. A visual monitoring system for the operating status of an elevator energy feedback device, 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, a method for visually monitoring the operating status of an elevator energy feedback device according to any one of claims 1-9 is provided.

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