A control and adjustment method and system for an overhead ground wire single-screw lifter

Abstract

This application relates to the technical field of overhead ground wire lifter control, and specifically relates to a control and adjustment method and system for a single-screw overhead ground wire lifter. The method includes: obtaining the tension and vibration intensity of the chain during the lifting of the overhead ground wire, extracting the change periods of the tension and vibration intensity, constructing the tension change degree and vibration severity degree, obtaining the degree of wind interference of the chain in the single-screw lifter at the current moment, and combining the chain tension decline trend and vibration intensity increase trend at multiple adjacent sampling moments at the current moment to obtain the chain looseness degree of the single-screw lifter at the current moment, so as to obtain the feedback tight wire force in the tight wire device at the current moment; according to the feedback tight wire force and the actual tight wire force in the tight wire device at the current moment, using a PID controller to control and adjust the tight wire force of the tight wire device. This application can accurately adjust the tight wire force in the tight wire device.

Description

Technical Field

[0001] This application relates to the technical field of overhead ground wire lifter control, and particularly to a control and adjustment method and system for a single-screw overhead ground wire lifter. Background Art

[0002] The overhead ground wire is a circuit laid to prevent the transmission line from being directly struck by lightning. However, under adverse working conditions such as unbalanced tension and thunderstorms, the fittings of the overhead ground wire will be worn and corroded. It is necessary to check and replace the fittings in time. The single-screw lifter is a device for lifting the overhead ground wire over a short distance. Controlling and adjusting the single-screw lifter can achieve safe and stable lifting of the overhead ground wire, thus ensuring the safety during the replacement of the overhead ground wire and reducing the risk of maintenance operations. Therefore, accurately controlling and adjusting the single-screw overhead ground wire lifter can effectively ensure the safety during the maintenance of the overhead ground wire, which has important practical significance in the actual maintenance and replacement applications of the overhead ground wire.

[0003] Currently, common overhead ground wire lifters mainly include fixed brackets, chains, ground wire hooks, and wire tensioners. During the lifting of the overhead ground wire, the wire tensioner in the lifter tightens the brake in time to lift the overhead ground wire safely and stably. However, due to the instability of the force and vibration conditions of the chain during the lifting of the ground wire, the wire tensioner in the existing single-screw overhead ground wire lifter is prone to insufficient wire tightening force after the overhead ground wire is lifted. And because the wire tensioner fails to tighten the brake in time, the overhead ground wire is prone to accidentally slip, resulting in poor safety and reliability during the lifting of the ground wire. Summary of the Invention

[0004] In order to solve the above technical problems, the purpose of this application is to provide a control and adjustment method and system for a single-screw overhead ground wire lifter. The specific technical solutions adopted are as follows:

[0005] The embodiment of this application provides a control and adjustment method for a single-screw overhead ground wire lifter, including the following steps:

[0006] Obtain the tension and vibration intensity of the chain during the lifting of the overhead ground wire;

[0007] Perform frequency domain transformation on the tension and vibration intensity respectively to extract the change periods of the tension and vibration intensity;

[0008] By analyzing the degree of frequent change of the tension of the chain in the single-screw lifter and the severity of the change of the vibration intensity with time within each change period, construct the tension change degree and the vibration severity respectively;

[0009] Obtain the wind interference degree of the chain in the single-screw hoist at the current moment based on the correlation between the tensile force change degree and the vibration intensity during each change cycle before the current moment, as well as the average level of the tensile force change degree and the average level of the vibration intensity.

[0010] Analyze the downward trend of the chain tensile force and the upward trend of the vibration intensity at multiple adjacent sampling moments at the current moment, construct the tightening and downward trend degree on the chain at the current moment, and combine the wind interference degree of the chain in the single-screw hoist to obtain the chain looseness degree of the single-screw hoist at the current moment. Utilize the change difference of the chain looseness degree and the tightening force in the wire tightener and the preset wire tightening force adjustment amount at the current moment to obtain the feedback tightening force in the wire tightener at the current moment.

[0011] Control and adjust the tightening force of the wire tightener using a PID controller according to the feedback tightening force and the actual tightening force in the wire tightener at the current moment.

[0012] Preferably, the extraction of the change cycles of the tensile force and the vibration intensity further includes:

[0013] Obtain the vectors formed by the tensile force and the vibration intensity at all historical sampling moments within a preset time duration before the current moment in chronological order, as the tensile force vector and the vibration intensity vector at the current moment.

[0014] Perform a frequency-domain transformation on the tensile force vector at the current moment to obtain the amplitudes of all frequencies in the frequency domain. Take the reciprocal of the frequency corresponding to the maximum amplitude as the tensile force change cycle within a short time before the current moment. Correspondingly, for the vibration intensity vector, use the fast Fourier transform to obtain the vibration change cycle within a short time before the current moment.

[0015] Preferably, the construction of the tensile force change degree further includes:

[0016] Arrange the tensile forces within each tensile force change cycle before the current moment in ascending order of time to form the tensile force cycle vector for each tensile force change cycle. Correspondingly, for the vibration intensity within each vibration cycle, obtain the vibration cycle vector for each vibration change cycle.

[0017] For each tensile force cycle vector, obtain the first-order difference sequence of the tensile force cycle vector, count the number of all non-zero elements in the first-order difference sequence, denoted as the change frequency, and calculate the mean value of the absolute values of all non-zero elements in the first-order difference sequence, denoted as the average change amplitude. Take the product of the change frequency and the average change amplitude as the tensile force change degree within each tensile force change cycle.

[0018] Preferably, the construction of the vibration intensity further includes:

[0019] For each vibration period vector, calculate the mean value of the absolute values of all elements in the first-order difference sequence of the vibration period vector, which is used as the vibration severity of each vibration change period.

[0020] Preferably, the calculation formula for the degree of wind interference on the chain in the single-screw lifter at the current moment is:

[0021] ; in the formula, is the degree of wind interference on the chain in the single-screw lifter at the current moment, is the correlation degree between the tensile change degree vector and the vibration severity vector at the current moment, where the tensile change degrees of all tensile change periods are arranged in ascending order of time to form the tensile change degree vector at the current moment, and the vibration severities of all vibration change periods are arranged in ascending order of time to form the vibration severity vector at the current moment, is the mean value of the elements in the tensile change degree vector at the current moment, is the mean value of the elements in the vibration severity vector at the current moment.

[0022] Preferably, the construction of the tightening and descending trend degree on the chain at the current moment includes:

[0023] Take the multiple moments with the closest time intervals to the current moment as the adjacent sampling moments of the current moment. According to the chain tensile change situation and vibration intensity change situation at the multiple adjacent sampling moments, obtain the tensile descending trend amount and vibration ascending trend amount at the current moment;

[0024] The product of the tensile descending trend amount and the vibration ascending trend amount at the current moment is determined as the tightening and descending trend degree on the chain at the current moment.

[0025] Preferably, the tensile descending trend amount and the vibration ascending trend amount at the current moment further include:

[0026] Arrange the chain tensile forces and vibration intensities at the multiple adjacent sampling moments in ascending order of time respectively to form the tensile trend vector and vibration trend vector at the current moment, and calculate the first-order difference vectors of the tensile trend vector and vibration trend vector at the current moment respectively;

[0027] The sum of the absolute values of all negative values in the first-order difference vector of the tensile trend vector is used as the tensile descending trend amount at the current moment, and the sum of all positive values in the first-order difference vector of the vibration trend vector is used as the vibration ascending trend amount at the current moment.

[0028] Preferably, the calculation process of the chain looseness degree of the single-screw lifter at the current moment is:

[0029] ; in the formula, is the chain looseness of the single-screw hoist at the current moment, is the exponential function with the natural constant as the base, is the degree of wind interference on the chain in the single-screw hoist at the current moment, is the tightening and descending trend degree on the chain at the current moment.

[0030] Preferably, the calculation process of the feedback wire-tightening force in the wire tightener at the current moment is as follows:

[0031] ; in the formula, is the feedback wire-tightening force in the wire tightener at the current moment, is the wire-tightening force in the wire tightener at the current moment, is the chain looseness at the current moment, is the chain looseness at the previous sampling moment of the current moment, is the preset wire-tightening force adjustment amount, where the wire-tightening force adjustment amount does not exceed 10% of.

[0032] The embodiment of the present application also provides an overhead ground wire single-screw hoist control and adjustment system, including a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, the steps of the method described in any one of the above are realized.

[0033] As can be seen from the above, a control and adjustment method and system for an overhead ground wire single-screw hoist provided by the present application has at least the following beneficial effects:

[0034] The present application uses FFT fast Fourier transform to obtain the change periods of the pulling force and vibration intensity, which helps to more accurately extract the periodic characteristics of the pulling force and vibration intensity subsequently, so as to more accurately obtain the chain looseness in different periods during the lifting process of the overhead ground wire, and realize more accurate control and adjustment of the tightening force in the wire tightener;

[0035] At the same time, the present application accurately evaluates the interference effect of the wind on the chain during high-altitude operations according to the frequent change characteristics and severe jitter characteristics of the chain pulling force on the chain within a short time before the current moment, and at the same time, according to the trend characteristics of the pulling force and vibration intensity of the chain at the adjacent sampling moments of the current moment, accurately evaluates the descending trend characteristics of the contraction force on the chain, which is beneficial to timely control and adjustment of the wire-tightening force in the wire tightener at the current moment, avoiding the accidental slipping of the overhead ground wire due to the failure of the wire tightener to tighten and brake in time, and improving the timeliness of the tightening and braking of the wire tightener in the single-screw hoist;

[0036] This application combines the degree of wind interference on the chain in a single-screw hoist and the decreasing trend characteristics of the contraction force on the chain to more accurately evaluate the looseness of the chain during high-altitude operations, thereby more accurately feedback-adjusting the tightening force in the wire tightener, avoiding the situation of insufficient tightening force that is prone to occur after the overhead ground wire is lifted, and improving the safety and reliability during the lifting process of the overhead ground wire. Brief Description of the Drawings

[0037] To more clearly illustrate the technical solutions and advantages in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0038] Figure 1 It is a flowchart of the steps of a control and adjustment method for a single-screw hoist of an overhead ground wire provided by the present application;

[0039] Figure 2 It is a schematic diagram of the construction process of the tightening decline degree provided by the present application. Detailed Embodiments

[0040] To further elaborate on the technical means and effects adopted by the present application to achieve the intended invention purpose, the following, in combination with the drawings and preferred embodiments, details the specific embodiments, structures, features, and effects of a control and adjustment method and system for a single-screw hoist of an overhead ground wire proposed according to the present application. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0041] Unless otherwise specified and limited, terms such as "including", "comprising", or any other variant thereof are intended to cover non-exclusive inclusion, so that a circuit structure, article, or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or elements inherent to such article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of another identical element in the article or device including the said element. Additionally, the term "and / or" used herein includes any and all combinations of one or more of the related listed items. All technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0042] The following specifically describes the specific solutions of a control and adjustment method and system for an overhead ground wire single-screw hoist provided by the present application in conjunction with the accompanying drawings.

[0043] Please refer to Figure 1 , which shows a flowchart of the steps of a control and adjustment method for an overhead ground wire single-screw hoist provided by an embodiment of the present application, including the following steps:

[0044] Step 1: Obtain the tension of the chain and the vibration intensity during the lifting of the overhead ground wire.

[0045] As the lightning protection wire of the transmission line, the overhead ground wire is extremely important for the safe and stable operation of the power system. When the fittings at the hanging point of the overhead ground wire are severely worn, it is necessary to lift the overhead ground wire through a single-screw hoist and replace the fittings at the hanging point of the overhead ground wire.

[0046] During the process of lifting the overhead ground wire by the single-screw hoist, a tension sensor and a vibration sensor are used to sample the tension of the chain and the vibration intensity in real time, and the tension and vibration intensity at each sampling moment during the lifting of the overhead ground wire are obtained. In this embodiment, the sampling rates of the tension and the vibration intensity are both 100 Hz, and the implementer can set the sampling rate according to the specific situation, and this embodiment does not make special limitations on this.

[0047] Step 2: Perform frequency-domain transformation on the tension and the vibration intensity respectively to extract the change periods of the tension and the vibration intensity.

[0048] Lifting the overhead ground wire is a high-altitude operation. Generally, it is easily affected by the interference of wind force. When the tightening effect of the chain in the single-screw hoist is poor, under the interference of wind force at high altitude, the chain will have obvious vibration phenomena, and the chain tension will have unstable characteristic changes. At this time, the risk of accidental slipping of the overhead ground wire is relatively high, which will cause serious safety hazards during the lifting of the overhead ground wire. Therefore, it is necessary to analyze the wind interference characteristics of the chain in the single-screw hoist, so as to more accurately control and adjust the tightening force in the wire tightener to ensure the stability and safety during the lifting of the overhead ground wire.

[0049] Since the tightening force of the wire tightener is at a relatively high level when starting to lift the overhead ground wire, at this time, the tightening degree of the chain is relatively high, with high stability and safety. Therefore, during the initialization time of lifting the overhead ground wire, no additional control and adjustment of the tightening force of the wire tightener is required. In this embodiment, the first 30 s of the start of lifting the overhead ground wire is used as the initialization time, and the tightening force of the wire tightener is not controlled and adjusted during the initialization time. The implementer can select the length of the initialization time according to the actual situation.

[0050] In order to control and adjust the wire tightening force in the wire tightener in a timely and accurate manner subsequently, vectors composed of the tensile force and vibration intensity at all historical sampling moments within a preset time period before the current moment in chronological order are obtained as the tensile force vector and vibration intensity vector at the current moment. In this embodiment, the preset time period is 20 s. The tensile force vector and vibration intensity vector reflect the changes in tensile force and vibration intensity over time within a short period before the current moment. By analyzing the periodic change characteristics of the tensile force and vibration intensity at historical sampling moments before the current moment, it helps to control and adjust the tightening force in the wire tightener in a timely manner and avoid potential safety hazards caused by wire tightening delays in the wire tightener.

[0051] Further, perform a frequency domain transformation on the tensile force vector at the current moment to obtain the amplitudes of all frequencies in the frequency domain, and take the reciprocal of the frequency corresponding to the maximum amplitude as the tensile force change period within a short period before the current moment. Correspondingly, for the vibration intensity vector, use the fast Fourier transform to obtain the vibration change period within a short period before the current moment. Preferably, in this embodiment, use the FFT fast Fourier transform to obtain the change periods of the tensile force and vibration intensity respectively. Take the tensile force vector at the current moment as the input of the FFT fast Fourier transform, use the FFT fast Fourier transform to obtain the amplitudes of all frequencies in the frequency domain of the tensile force data, and take the reciprocal of the frequency corresponding to the maximum amplitude as the tensile force change period within a short period before the current moment. Correspondingly, for the vibration intensity vector, use the FFT fast Fourier transform to extract the vibration change period within a short period before the current moment. Among them, the FFT fast Fourier transform is a well-known technology, and the specific process will not be elaborated.

[0052] Using the FFT fast Fourier transform to obtain the change periods of the tensile force and vibration intensity helps to more accurately extract the periodic characteristics of the tensile force and vibration intensity subsequently, so as to more accurately analyze the tightening degree of the chain in different periods during the lifting process of the overhead ground wire, and realize more accurate control and adjustment of the wire tightening force in the wire tightener.

[0053] Step 3: By analyzing the intensity characteristics of the frequent changes in the tensile force on the chain in the single-screw lifter and the severity of the change in vibration intensity over time for each change period, obtain the degree of wind interference of the chain in the single-screw lifter.

[0054] In order to analyze the tensile force period characteristics and vibration period characteristics of the chain in the single-screw lifter for each change period, arrange the tensile forces within each tensile force change period before the current moment in ascending order of time to form the tensile force period vector of each tensile force change period. Correspondingly, for the vibration intensity within each vibration period, and arrange the vibration intensities within each vibration change period before the current moment in ascending order of time to form a vector as the vibration period vector of each vibration change period.

[0055] The tensile force period vector and the vibration period vector respectively reflect the change characteristics of the tensile force and the change characteristics of the vibration intensity in each change period. If the tensile force changes more frequently with time and the vibration intensity changes more violently with time within the change period, to a certain extent, it indicates that the stability of the chain within this change period is worse, and there is a higher risk of accidental slipping of the overhead ground wire. It is necessary to timely control and adjust the tightening force in the wire tightener.

[0056] Further, for each tensile force period vector, obtain the first-order difference sequence of the tensile force period vector, count the number of all non-zero elements in the first-order difference sequence, denoted as the change frequency, and calculate the mean value of the absolute values of all non-zero elements in the first-order difference sequence, denoted as the average change amplitude. Take the product of the change frequency and the average change amplitude as the tensile force change degree in each tensile force change period. The tensile force change degree reflects the intensity characteristic of the frequent change of the tensile force on the chain within the tensile force change period. The greater the intensity characteristic of the frequent change of the tensile force on the chain, the more likely it is to have a situation where the tightening force of the chain is insufficient at this time, and the more timely the tightening force in the wire tightener should be controlled and adjusted.

[0057] At the same time, obtain the first-order difference sequence of the vibration period vector of each vibration change period, and calculate the mean value of the absolute values of all elements in the first-order difference sequence of the vibration period vector as the vibration severity of each vibration change period. The vibration severity reflects the severity of the change of the vibration intensity with time in the vibration change period. The higher the severity of the change of the vibration intensity with time, the more it can reflect the severe vibration characteristics affected by the wind force when the tightening force of the chain in the single-screw lifter is poor, and the more it is necessary to control and adjust the tightening force in the wire tightener.

[0058] Step 4: According to the correlation between the tensile force change degree and the vibration severity in each change period before the current moment, as well as the average level of the tensile force change degree and the average level of the vibration severity, obtain the degree of wind interference of the chain in the single-screw lifter at the current moment.

[0059] Since when the tightening force of the chain in the single-screw lifter is insufficient, under the action of the wind field force at high altitude, it will simultaneously affect the change of the tensile force and the vibration intensity in the chain. If the correlation between the intensity characteristic of the frequent change of the tensile force and the severity characteristic of the vibration is stronger within a short time before the current moment, and the instability of the chain in the single-screw lifter within a short time is higher, it can more reflect that the interference characteristic of the chain by the wind force within a short time before the current moment is stronger, and there is a higher risk of slipping of the overhead ground wire at this time.

[0060] Through the above analysis, the degrees of change in tension for all tension change cycles are arranged in ascending order of time to form the tension change degree vector at the current moment. The tension change degree vector reflects the periodic characteristics of the tension change degree of the chain within a short period of time before the current moment. At the same time, the degrees of vibration intensity for all vibration change cycles are arranged in ascending order of time to form the vibration intensity vector at the current moment. The vibration intensity vector reflects the periodic characteristics of the vibration intensity on the chain within a short period of time before the current moment.

[0061] Calculate the degree of correlation between the tension change degree vector and the vibration intensity vector after length alignment. The measurement methods for the degree of correlation can be covariance, Pearson correlation coefficient. In this embodiment, covariance is selected to measure the degree of correlation between the two vectors. The calculation of covariance is a well-known technology, and the specific process will not be elaborated here. It should be noted that when calculating the degree of correlation between vectors to maintain the alignment of vector lengths, the number of elements in the tension change degree vector and the vibration intensity vector corresponding to the current moment are respectively counted. If the number of elements in the two vectors is not equal, the vector with fewer elements is filled with the mean value to make the lengths of the tension change degree vector and the vibration intensity vector equal. The mean value filling process is an existing technology and will not be elaborated in this embodiment. Implementers can also adopt other existing filling methods, and this embodiment does not make special restrictions on this. If the number of elements in the two vectors is equal, no mean value filling process is required.

[0062] Through the above analysis, calculate the degree of wind interference on the chain in the single-screw hoist at the current moment:

[0063] ; where is the degree of wind interference on the chain in the single-screw hoist at the current moment, is the degree of correlation between the tension change degree vector and the vibration intensity vector at the current moment. Among them, the degrees of change in tension for all tension change cycles are arranged in ascending order of time to form the tension change degree vector at the current moment, and the degrees of vibration intensity for all vibration change cycles are arranged in ascending order of time to form the vibration intensity vector at the current moment. is the mean value of the elements in the tension change degree vector at the current moment, is the mean value of the elements in the vibration intensity vector at the current moment.

[0064] The degree of periodic wind interference on the chain in the single-screw hoist reflects the influence characteristics of the wind interference when the chain tightening force difference occurs. The lower the tightening degree of the chain, the more easily it is affected by the wind force at high altitude. At this time, it is more necessary to control and adjust the tightening force in the wire tightener to reduce the safety hazards during the lifting process of the overhead ground wire.

[0065] Step 5: Analyze the chain tension decline trend and vibration intensity increase trend at multiple adjacent sampling moments at the current moment, construct the tightening decline trend degree on the chain at the current moment, and combine the degree of wind interference on the chain in the single-screw hoist to obtain the chain looseness degree of the single-screw hoist at the current moment. Utilize the change difference of the chain looseness degree and the tightening force and preset tightening force adjustment amount in the tightener at the current moment to obtain the feedback tightening force in the tightener at the current moment.

[0066] Meanwhile, when the overhead ground wire is lifted, if the tightening force on the chain in the single-screw hoist decreases, the tension of the chain will show a downward trend in adjacent time, while the vibration intensity of the chain will show an upward trend in adjacent time. Therefore, if the downward trend of the tension in the adjacent sampling time period at the current moment is stronger, and the upward trend of the vibration intensity is stronger, it can better reflect the characteristic of the decrease in the tightening force of the chain in the single-screw hoist at the current moment, and the tightening force in the tightener should be controlled and adjusted in a timely manner.

[0067] Further, the K moments with the closest time interval to the current moment are used as the K adjacent sampling moments of the current moment. In this embodiment, K is taken as 50, and the implementer can select it according to the actual situation.

[0068] The vectors formed by arranging the chain tensions and vibration intensities of the K adjacent sampling moments of the current moment in ascending order of time are respectively used as the tension trend vector and vibration trend vector of the current moment. Calculate the first-order difference vectors of the tension trend vector and vibration trend vector of the current moment respectively. The sum of the absolute values of all negative values in the first-order difference vector of the tension trend vector is used as the tension decline trend amount at the current moment, and the sum of all positive values in the first-order difference vector of the vibration trend vector is used as the vibration increase trend amount at the current moment. The product of the tension decline trend amount and the vibration increase trend amount at the current moment is used as the tightening decline trend degree on the chain at the current moment. The tightening decline trend degree reflects the decline trend characteristic of the tightening force on the chain between adjacent sampling moments. If the decline trend characteristic of the tightening force on the chain is stronger, and the degree of wind interference on the chain in the single-screw hoist is higher at this time, it can better reflect the characteristic of low tightening degree of the chain. At this time, the tightening force in the tightener should be adjusted upwards in a timely manner to avoid the risk of accidental slipping of the overhead ground wire. Specifically, the schematic diagram of the construction process of the tightening decline trend degree on the chain at the current moment is as Figure 2 shown.

[0069] Furthermore, through the above analysis in this embodiment, calculate the chain looseness degree of the single-screw hoist at the current moment:

[0070] ; where is the chain looseness degree of the single-screw hoist at the current moment, is the exponential function with the natural constant as the base, is the degree of wind interference on the chain in the single-screw hoist at the current moment, is the degree of tightening and descending trend on the chain at the current moment.

[0071] The chain looseness reflects the characteristic of low tightening degree of the chain in the single-screw hoist. The lower the tightening degree of the chain in the single-screw hoist, the higher the adjustment force for the wire tightening in the wire tightener, so as to avoid the risk of the overhead ground wire slipping.

[0072] Obtain the wire tightening force in the wire tightener at the current moment by using a tension sensor, and combine it with the change of the chain looseness to calculate the feedback wire tightening force in the wire tightener at the current moment:

[0073] ; In the formula, is the feedback wire tightening force in the wire tightener at the current moment, is the wire tightening force in the wire tightener at the current moment, is the chain looseness at the current moment, is the chain looseness at the previous sampling moment of the current moment, is the preset wire tightening force adjustment amount. In order to avoid excessive adjustment force and cause damage to the chain, the wire tightening force adjustment amount does not exceed 10% of, that is The value range of is 0 - 10% * Nc. In this embodiment, the adjustment amount is set to 5% * Nc.

[0074] Therefore, during the lifting process of the overhead ground wire, if the looseness degree of the chain in the single-screw hoist at the current moment is larger than that at the previous sampling moment, it indicates that the tightening force on the chain is insufficient at this time. At this time, the wire tightening force in the wire tightener is appropriately increased, so as to ensure a good tightening effect in the wire tightener, and thus avoid the situation that the ground wire accidentally slips due to the wire tightener not tightening and braking in time, improving the safety and reliability during the lifting process of the overhead ground wire; on the contrary, if the looseness degree of the chain in the single-screw hoist at the current moment is smaller than that at the previous sampling moment, it indicates that the tightening force on the chain is sufficient at this time. At this time, the tightening degree of the chain can be continuously increased, and the wire tightening force in the wire tightener is appropriately decreased, so as to avoid the risk of the chain breaking in the single-screw hoist due to excessive wire tightening force in the wire tightener.

[0075] Step 6: According to the feedback wire tightening force and the actual wire tightening force in the wire tightener at the current moment, use a PID controller to control and adjust the wire tightening force of the wire tightener.

[0076] In order to accurately control the wire tightening force in the wire tightener, the feedback wire tightening force and the actual wire tightening force in the wire tightener at the current moment are input into the PID controller. The PID controller adjusts the wire tightening force in the wire tightener by calculating the error between the feedback wire tightening force and the actual wire tightening force. The output of the PID controller is the control signal for the wire tightening force in the wire tightener. The drive motor in the wire tightener controls the wire tightening force of the wire tightener to approach the feedback wire tightening force corresponding to the current moment, so as to realize the control and adjustment of the wire tightening force in the wire tightener of the single-screw lifter.

[0077] Based on the same inventive concept as the above method, an embodiment of the present application also provides a control and adjustment system for an overhead ground wire single-screw lifter, including a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, it implements the steps of any one of the above methods for controlling and adjusting an overhead ground wire single-screw lifter.

[0078] It can be understood that the above sequence of embodiments of the present application is only for description and does not represent the advantages or disadvantages of the embodiments. And the above describes specific embodiments of this specification. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0079] Each embodiment in this specification is described in a progressive manner. The same or similar parts between each embodiment can be referred to each other, and the key point of each embodiment is to illustrate the differences from other embodiments.

[0080] The above content is only the implementation manner of the present application and is not used to limit the scope of the present application. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied to other related technical fields, shall be included in the protection scope of the present application by the same token.

Claims

1. A control and adjustment method for an overhead ground wire single screw lifter, characterized in that: The following steps are involved: Obtain the chain tension and vibration intensity during the overhead ground wire lifting process; Perform frequency domain transformation on tension and vibration intensity to extract the variation period of tension and vibration intensity; By analyzing the degree of frequent changes in the tension of the chain in the single-screw lifter in each change cycle and the severity of the change in vibration intensity over time, the tension change degree and vibration severity are constructed respectively; According to the correlation between the tension change degree and the vibration severity in each change cycle before the current moment, as well as the average level of the tension change degree and the average level of the vibration severity, the wind interference degree of the chain in the single-screw lift at the current moment is obtained; Analyze the downward trend of chain tension and the upward trend of vibration intensity at multiple adjacent sampling moments at the current moment, construct the downward trend of tightening on the chain at the current moment, and combine the degree of wind interference of the chain in the single-screw lifter to obtain the chain looseness of the single-screw lifter at the current moment. Use the change difference of chain looseness and the tightening force in the tightening device at the current moment and the preset tightening force adjustment amount to obtain the feedback tightening force in the tightening device at the current moment; According to the feedback tightening force and actual tightening force in the tightening device at the current moment, the tightening force of the tightening device is controlled and adjusted by using a PID controller.

2. A method for controlling and adjusting an overhead ground wire single screw lifter according to claim 1, characterized in that: The extraction of the variation cycle of the tension and vibration intensity further includes: Obtain the vectors composed of the tension and vibration intensity at all historical sampling moments within a preset time before the current moment in chronological order, as the tension vector and vibration intensity vector at the current moment; The tension vector at the current moment is transformed in the frequency domain to obtain the amplitudes of all frequencies in the frequency domain, and the inverse of the frequency corresponding to the maximum amplitude is taken as the tension change period in the short time before the current moment; accordingly, for the vibration intensity vector, the fast Fourier transform is used to obtain the vibration change period in the short time before the current moment.

3. The method for controlling and adjusting an overhead ground wire single screw lifter according to claim 1, characterized in that: The construction of the tension variation degree further includes: Arrange the tensions in each tension change period before the current moment in ascending order of time to form a tension period vector of each tension change period, and accordingly, obtain a vibration period vector of each vibration change period for the vibration intensity in each vibration period; For each tension periodic vector, the first-order difference sequence of the tension periodic vector is obtained, the number of all non-zero elements in the first-order difference sequence is counted, recorded as the change frequency, and the mean of the absolute values ​​of all non-zero elements in the first-order difference sequence is calculated, recorded as the average change amplitude, and the product of the change frequency and the average change amplitude is taken as the tension change degree in each tension change period.

4. A method for controlling and adjusting an overhead ground wire single screw lifter as claimed in claim 3, characterized in that: The construction of the vibration severity further includes: For each vibration period vector, the mean of the absolute values ​​of all elements in the first-order difference sequence of the vibration period vector is calculated as the vibration severity of each vibration change period.

5. The method for controlling and adjusting an overhead ground wire single-screw lifter according to claim 4, characterized in that: The corresponding calculation formula for the wind interference degree of the chain in the single-screw lifter at the current moment is: ; In the formula, is the degree of wind interference on the chain in the single-screw lifter at the current moment, is the correlation between the tension change degree vector and the vibration severity vector at the current moment, wherein the tension change degrees of all tension change cycles are arranged in ascending time order to form the tension change degree vector at the current moment, and the vibration severity degrees of all vibration change cycles are arranged in ascending time order to form the vibration severity vector at the current moment, is the mean value of the elements in the tension change vector at the current moment, is the mean value of the elements in the vibration severity vector at the current moment.

6. The method for controlling and adjusting an overhead ground wire single-screw lifter according to claim 1, characterized in that: The construction of the tightening downward trend degree on the chain at the current moment includes: The multiple moments with the closest time intervals to the current moment are all used as adjacent sampling moments of the current moment, and the tension downward trend amount and the vibration upward trend amount of the current moment are obtained according to the chain tension change and vibration intensity change at the multiple adjacent sampling moments; The product of the downward trend of tension at the current moment and the upward trend of vibration is determined as the downward trend degree of tightening on the chain at the current moment.

7. A method for controlling and adjusting an overhead ground wire single screw lifter as claimed in claim 6, characterized in that: The tension downward trend amount and vibration upward trend amount at the current moment further include: Arranging the chain tension and vibration intensity at the plurality of adjacent sampling moments in ascending order of time to form a tension trend vector and a vibration trend vector at the current moment, and calculating the first-order difference vector of the tension trend vector and the vibration trend vector at the current moment respectively; The sum of the absolute values ​​of all negative values ​​in the first-order difference vector of the tension trend vector is taken as the tension downward trend quantity at the current moment, and the sum of all positive values ​​in the first-order difference vector of the vibration trend vector is taken as the vibration upward trend quantity at the current moment.

8. The method for controlling and adjusting an overhead ground wire single-screw lifter according to claim 1, characterized in that: The calculation process of the chain looseness of the single-screw lifter at the current moment is: ; In the formula, is the chain looseness of the single screw lifter at the current moment, is an exponential function with a natural constant as base, is the degree of wind interference on the chain in the single-screw lifter at the current moment, It is the degree of tightening downward trend on the chain at the current moment.

9. The method for controlling and adjusting an overhead ground wire single-screw lifter according to claim 1, characterized in that: The calculation process of the feedback tensioning force in the tensioner at the current moment is: ; In the formula, is the feedback tension force in the tensioner at the current moment, is the tension force in the tensioner at the current moment, is the chain looseness at the current moment, is the chain looseness at the sampling moment before the current moment, is the preset tension adjustment amount, where the tension adjustment amount does not exceed 10% of.

10. An overhead ground wire single-screw lifter control and adjustment system, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 9 are implemented.

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