Power transmission line anti-galloping robot control method based on online power taking

Abstract

The invention relates to the technical field of power transmission line detection, in particular to a power transmission line anti-galloping robot control method based on online power taking. Comprising the steps of establishing a data model, installing the anti-galloping robot, testing the anti-galloping robot and recording initial data, real-time monitoring and dynamic control are combined, galloping of the power transmission line can be accurately restrained, the robot rapidly judges and moves to an optimal anti-galloping point according to galloping data, line quality distribution is adjusted through the weight of the robot, and the anti-galloping effect is improved. The damping characteristic is changed; the device effectively reduces wire abrasion and fracture risks, reduces the possibility of electrical faults and tower damage, greatly improves the operation safety and stability of a power transmission line, ensures continuous and reliable power supply, reduces power failure accidents caused by galloping, and provides stable power guarantee for social production and life.

Description

Technical Field

[0001] The present invention relates to the technical field of power transmission line detection, and in particular to a power transmission line anti-dancing robot control method based on online power extraction. Background Art

[0002] The galloping of overhead transmission lines is an extremely serious problem in the field of power transmission, especially in areas with complex terrain and changeable climate. The complex terrain across which the transmission lines cross makes the galloping phenomenon very easy to occur.

[0003] Galloping poses a huge threat to transmission lines. Mechanically, it can cause wear, loosening, or even breakage of conductors, hardware, and components (such as spacers, suspension clamps, etc.), seriously shortening the service life of the equipment. Electrically, it may cause the phase-to-phase distance of conductors to shorten or collide, causing flashover, conductor burns, and other faults, which in turn lead to tripping, power outages, and other accidents, affecting the stability of power supply. From the perspective of pole towers, the huge dynamic loads generated by galloping will threaten the safety of pole towers, and in severe cases may even cause the pole towers to collapse and be damaged, bringing huge economic losses and safety risks.

[0004] Existing anti-dancing devices are mainly divided into the following categories based on the anti-dancing principle:

[0005] First, the dancing is suppressed by changing the structural characteristics, such as eliminating detuning, suppressing torsion, eccentric weights, etc. At present, most anti-dancing devices are based on this principle, but the applicability of different structural methods varies;

[0006] Second, increase the damping value of the wire itself to resist dancing;

[0007] Third, increase wind resistance to suppress dancing;

[0008] Fourth, prevent the conductor from being covered with ice to prevent dancing, such as using special alloy materials or de-icing devices;

[0009] Fifth, increase wire tension or reduce gear spacing to resist galloping.

[0010] However, various dancing theories have their applicable premises and characteristics, and the applicability and design points of corresponding anti-dancing equipment are different. So far, there is no anti-dancing device that can completely eliminate the dancing phenomenon, and various places lack mature experience and clear guidance in anti-dancing work.

[0011] At present, anti-galloping work focuses on surface treatment and fails to fundamentally solve the galloping problem. In reality, the anti-galloping devices commonly used in high-voltage transmission lines, such as double pendulum type, wire clamp rotary type and interphase spacer, have certain prevention and control effects, but there is a large gap between the actual effect and the theoretical design, and the scope of application is limited. Summary of the invention

[0012] In order to make up for the shortcomings of the prior art, the present invention aims to provide a transmission line anti-dancing robot control method based on online power supply, which is applied to high-voltage transmission lines in complex environments and has a wide range of application scenarios. Through real-time online monitoring and instant response mechanisms, it can effectively control or reduce the dancing phenomenon of transmission lines, which will significantly improve the safety and reliability of the transmission system, reduce line damage and power supply interruption events caused by dancing, and in addition, it will promote the progress of power grid monitoring technology and promote the implementation of smart grid technology. The technical solution adopted by the present invention to solve its technical problems is: a transmission line anti-dancing robot control method based on online power supply, comprising the following steps:

[0013] S1: Establish a data model. Through experiments and data collection, establish a force model of the transmission line under the galloping state, and simultaneously establish an active anti-galloping model of dynamic damping control, that is, the influence and connection of different center of gravity positions and different mass distributions of the transmission line on the galloping amplitude and resonant frequency;

[0014] S2: Installation of the anti-dance robot: installing the posture sensor on the transmission line, and fixing the anti-dance robot on the transmission line; the anti-dance robot includes a fixing module, a control module, an online monitoring module and a power supply module;

[0015] The fixing module is used to fix the anti-dance robot on the power transmission line;

[0016] The control module is used to receive feedback data and control the movement of the anti-dance robot;

[0017] The online monitoring module is used to collect pictures, video information, and the coordinate information of the current anti-dance robot, the coordinate information of the transmission line, and the coordinate information of the posture sensor on the transmission line;

[0018] The power supply module is used to supply power to the anti-dance robot;

[0019] S4: Anti-dancing robot test: Start the anti-dancing robot, attitude sensor and ground control station, and perform functional tests on the control module, online monitoring module and drive module on the anti-dancing robot to ensure complete functions;

[0020] S4: Record initial data: After the anti-dance robot test in S3 is completed, record the coordinates of the power transmission line, the coordinates of the anti-dance robot and the coordinates of the posture sensor;

[0021] S5: Principle of use: During use, the online monitoring module is used to collect the coordinates of the transmission line, the anti-dance robot, and the posture sensor in real time. The coordinate translation parameters and zero-degree image fitting parameters between the initial data are compared to calculate the dancing rotation data. The control module is used to control the movement of the anti-dance drone, change the center of gravity position and mass distribution of the transmission line, and achieve anti-dance.

[0022] Furthermore, the distribution of the attitude sensors in S1 is carried out at equal distances or at non-equidistant distances according to the stress characteristics of the conductors, so as to ensure comprehensive monitoring of the dancing of the long-distance transmission line.

[0023] Furthermore, the online power supply module in S2 adopts a dual-branch online power supply system to power the anti-dancing robot; the dual-branch online power supply system includes a damping branch and an energy supply branch, and the damping branch and the energy supply branch are equivalent to a parallel relationship.

[0024] Furthermore, the damping branch includes a transmission bus, an open-type magnetic core, a coil winding and a capacitor. The open-type magnetic core material is a nanocrystalline magnetic core material. The magnetic core based on the nanocrystalline material has a small starting current and a high saturation magnetic induction intensity. The open-type magnetic core can meet the working conditions of hundreds of amperes of transmission cable current without entering saturation.

[0025] Furthermore, the energy extraction branch includes a conductor, a transformer, a voltage tracking rectifier control circuit, a signal conversion circuit, an MPPT controller, a DC-DC circuit and an equivalent load of a monitoring device. The conductor is connected to the transmission bus and the primary side of the transformer using a clamp, and the secondary side of the transformer is connected to the subsequent processing circuit and the load.

[0026] Furthermore, the energy extraction circuit also includes a sampling module and a current conversion voltage module; the sampling module obtains the DC side voltage and current value of the rectified output of the secondary coil of the transformer, and controls the current conversion voltage module to output voltage signals of different amplitudes according to the value through the MPPT algorithm control platform, inputs the voltage tracking rectification control circuit, adjusts the input voltage of the energy extraction branch, maintains the circuit parallel resonance and maximum power output, and provides stable power for the robot.

[0027] Furthermore, the dancing rotation data in S5 is a back-propagation neural network structure based on the BP algorithm. The power line dancing data processed by the neural network algorithm can identify the dancing state of the wire and extract the dancing frequency, amplitude and possible dancing area characteristic parameters by realizing nonlinear transformation from input to output.

[0028] The beneficial effects of the present invention are as follows:

[0029] 1. The control method of a power transmission line anti-dancing robot based on online power supply described in the present invention can accurately suppress the dancing of the power transmission line by combining real-time monitoring with dynamic control. The robot quickly judges and moves to the optimal anti-dancing point based on the dancing data, and uses its own weight to adjust the line mass distribution and change the damping characteristics; it effectively reduces the risk of wire wear and breakage, reduces the possibility of electrical failures and tower damage, greatly improves the safety and stability of power transmission line operation, ensures continuous and reliable power supply, reduces power outages caused by dancing, and provides stable power guarantee for social production and life.

[0030] 2. The control method of the anti-dancing robot for power transmission lines based on online power supply described in the present invention changes the coordinates based on the changes in the transmission line coordinates, the anti-dancing robot coordinates, and the posture acquisition of the posture sensor. Through real-time data comparison on the left, the acquisition machine can simulate the real-time change image of the transmission line. It can not only effectively adjust the position of the anti-dancing robot to effectively prevent dancing, but also predict the degree of damage to the hardware and towers involved in the transmission line according to the data, effectively reduce the cost of personnel inspection, quickly determine the service life of other spare parts such as lines, hardware, towers, etc., and realize intelligent maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention will be further described below in conjunction with the accompanying drawings.

[0032] Figure 1 is a flow chart of the method of the present invention;

[0033] Figure 2 It is the power transmission line-anti-dance robot vibration model of the present invention;

[0034] Figure 3 It is a schematic diagram of the first-order equivalent damping ratio under the same sag parameter of the present invention;

[0035] Figure 4 Schematic diagram of high-order equivalent damping ratio of the system under different sag parameters of the present invention;

[0036] Figure 5 is the system dynamic characteristics of the present invention under different damper installation positions;

[0037] Figure 6 is an equivalent circuit diagram of the damping branch of the present invention;

[0038] Figure 7 It is a simplified damping branch equivalent circuit of the present invention;

[0039] Figure 8 is an equivalent circuit diagram of the present invention;

[0040] Fig. 9 It is a schematic diagram of the control circuit of the energy taking system of the present invention; DETAILED DESCRIPTION

[0041] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0042] like Figure 1 As shown, the present invention proposes a control method for a power transmission line anti-dancing robot based on online power supply, comprising the following steps:

[0043] S1: Establish a data model. Through experiments and data collection, establish a force model of the transmission line under the galloping state, and simultaneously establish an active anti-galloping model of dynamic damping control, that is, the influence and connection of different center of gravity positions and different mass distributions of the transmission line on the galloping amplitude and resonant frequency;

[0044] The specific experiments include the following:

[0045] The stress model in the dancing state needs to consider multiple factors, including the geometric nonlinearity of the conductor, material nonlinearity, and the dynamic effects of wind load and ice load; the dancing stress of the conductor is a multi-physics field problem involving aeroelasticity, structural dynamics and possible thermal effects, which requires coupled analysis; when establishing the model, it is necessary to accurately predict the dynamic response of the conductor under wind excitation, including vibration frequency, amplitude and phase, etc.; the stress model needs to be verified through simulation and field tests to ensure the accuracy and reliability of the model.

[0046] Active anti-dancing technology experiment based on dynamic damping control:

[0047] Carry out dancing detection experiments on transmission lines with different center of gravity positions and different mass distributions to clarify the influence and relationship of the two key characteristics on the dancing amplitude and resonant frequency.

[0048] The experiment selected a wind tunnel laboratory as the experimental site, selected 8 transmission lines of the same model and length, and selected 8 shock-proof hammers and damping weight anti-dance devices corresponding to the above-mentioned wire models, which are equivalent to anti-dance robots, as experimental objects; the amplitude measurement system and the frequency measurement system were selected as experimental measuring instruments.

[0049] During the experiment, firstly, anti-vibration hammers and damping weight anti-dancing devices were placed at different positions on the transmission line to simulate different center of gravity positions and different mass distribution conditions of the line. Then, the wind tunnel laboratory was used to simulate the outdoor wind speed and direction to make the wire start to dance. Finally, an experimental measuring device was placed to measure and record the wire dancing in real time. The intrinsic relationship between dancing and quality was analyzed and used as a basis for modeling the anti-dancing dynamic damping mathematical model.

[0050] The motion equations for the entire transmission line-damper system are established, and the overall coordinate system of the conductor is defined as follows: Figure 2As shown, the damper is installed at a distance of x from the left and right tension towers. d1 and x d2 The position of the conductor is L, where L is the span, y, z, θ are the vertical, horizontal and torsional coordinates of the conductor respectively, m, EA, T are the unit length mass, axial stiffness and initial tension of each sub-conductor respectively; U is the incoming wind speed; the displacement vector of the conductor is recorded as D = [u, v, w, θ] T , where u, v, w, and θ are the axial, vertical, horizontal, and torsional displacements of the conductor respectively; the partial differential equation of the conductor motion is obtained according to Hamilton's principle:

[0051]

[0052] Where: P di For x di The additional force exerted by the damper on the wire at the position; V u 、V v 、V w , V are the elastic potential energies in the axial, vertical, horizontal and torsional directions respectively; c u 、c v 、c w , c are the damping coefficients in the axial, vertical, horizontal and torsional directions respectively; f u 、f v 、f w , f are the axial, vertical, horizontal and torsional wind loads respectively; S x , S y is the area moment of the icing conductor relative to the y-axis and z-axis; I is the moment of inertia of the split conductor cross section.

[0053] Using the Galerkin method, the solution of the above partial differential dancing equation can be decomposed into the product of the Galerkin function and the generalized displacement time history:

[0054]

[0055] Where n is the order of the Galerkin function; pure trigonometric function is used as the shape function:

[0056] φ j (x) = sin(jπx / L)

[0057] Considering that the conductor is equipped with a damper near the transmission tower, a higher-order Galerkin function is needed when using pure trigonometric functions as shape functions to more accurately express the damping characteristics of the system.

[0058] Substituting the product of the Galerkin function and the generalized displacement time history and the pure trigonometric function as the shape function into the partial differential equation, and then multiplying it by φj and integrating it along the axial direction of the wire, the system motion equation can be obtained:

[0059]

[0060] Where: M, C, K are mass matrix, damping matrix, and stiffness matrix respectively; q is the generalized displacement vector; F air is the wind load vector; P di For x di The sum of the damping force and spring force of the damper on the wire at the position is as follows:

[0061]

[0062] F air Perform Taylor series expansion at q = 0, ignore the displacement and velocity power above 2, and obtain the linearized part of the aerodynamic load:

[0063]

[0064] In the formula, C air , K air are the aerodynamic damping and aerodynamic stiffness matrices caused by wind loads, respectively, and their expressions are as follows:

[0065]

[0066] According to Lyapunov's first stability theorem, when the real part of the eigenvalue of the linearized motion equation of the conductor system is positive, the conductor will experience aerodynamic instability. By analyzing the eigenvalue of the system motion equation, the dynamic characteristic parameters of the conductor-damper system in all directions (i.e., the damping ratio of the self-oscillation mode and the self-oscillation frequency) can be obtained. In order to obtain the eigenvalue of the motion equation, Q=q is taken, and the system motion equation of the above second-order equation is converted into the first-order motion equation form through an appropriate form, and X=[Q,q] T , we can get:

[0067]

[0068] The matrix and The form is as follows:

[0069]

[0070] The corresponding eigenvalue λ and eigenvector x can be obtained by the following formula:

[0071]

[0072] According to existing research, the imaginary part of the eigenvalue Im(λj) is the circular frequency of each order vibration mode of the conductor. The total damping ratio of the conductor-damper system under wind load can be obtained from the real and imaginary parts of the eigenvalue:

[0073]

[0074] Where ξjs and ξja are the j-th order equivalent structural damping ratio and the aerodynamic damping ratio caused by wind load, respectively.

[0075] When the wind load Fair is 0, the first-order motion equation of the motion equation can be simplified to the free vibration equation of the wire-damper system, and the corresponding matrix and The formula in the form of is the equivalent structural damping ratio of the wire-damper system.

[0076] In order to study the influence of the line characteristics on the damper setting, the dimensionless line sag parameter is introduced:

[0077] η=10(mgL / T) 2 (EAL / TL e )

[0078] L e =L[1+8(f / L) 2 ]

[0079] Where f is the sag at the mid-span of the line.

[0080] Let two dampers with the same damping coefficient be symmetrically installed at a position L / 10 away from both ends of the conductor. For the five ice thickness conditions studied in this paper, the corresponding sag parameters η of the conductor system are 130, 153, 175, 205, and 240, respectively. The variation of the first three-order equivalent structural damping of the conductor-damper system with the damping coefficient of the damper under the above different sag parameters is calculated and analyzed. Considering that the variation trend of the system equivalent damping ratio with the damping coefficient of the damper is similar under different damper stiffness coefficients, in order to study the influence of the line sag parameters on the system damping ratio, a constant damper stiffness coefficient is adopted, that is, K=0. The corresponding calculation results are plotted in Figure 3 and Figure 4 .

[0081] Depend on Figure 3 It can be seen that the first-order damping ratio of the conductor-damper system is very sensitive to the change of the line sag parameter; as the line sag parameter decreases, the first-order modal maximum damping ratio of the system will show an increasing trend.

[0082] Depend on Figure 4It can be seen that the influence of the line sag parameter on the high-order (second-order and third-order) modal damping ratio is not obvious, and the maximum damping ratio of the high-order mode under different sag parameters can reach about 15%, which is enough to suppress the high-order modal dancing of the conductor. Existing literature research shows that the first-order dancing of the conductor is more easily excited than the high-order dancing, and the dancing energy is also mainly concentrated in the first-order mode. Therefore, this article will mainly optimize the installation position, damping coefficient and stiffness coefficient of the damper with the goal of improving the first-order equivalent structural damping ratio of the system.

[0083] The maximum first-order damping ratio ξmax that the system can achieve will change accordingly with the different damping positions, and the optimal damping coefficient combination corresponding to the maximum solution ξmax will also have significant differences; considering that the larger the damping coefficient, the more difficult it is to make the damper, so the damper position selection should maximize the system's first-order maximum damping ratio while minimizing the optimal damping coefficient value; in order to facilitate the actual application and installation of the damper, this paper selects the damper installation position to be 100 meters away from both ends of the wire.

[0084] The interval range of [L / 15L / 10] is set to ensure reliable connection with the tower body; the maximum damping ratio of the first-order mode that the system can achieve under different damper positions (damper stiffness coefficient K = 0) and the larger value max (Cd1-opt, Cd2-opt) in the optimal damping coefficient combination are calculated and analyzed; the corresponding results are shown in Figure 5 As shown;

[0085] Depend on Figure 5 (a) It can be seen that the first-order maximum damping ratio ξmax of the system will change with the installation position of the dampers on both sides. The closer the damper on either side is to the mid-span, the greater the first-order maximum damping ratio that the system can achieve.

[0086] And by Figure 5 (b) It can be seen that when the damper is installed symmetrically, the larger value of the optimal damping coefficient (Cd1-opt, Cd2-opt) is smaller than when it is installed asymmetrically.

[0087] Based on the dynamic damping mathematical model and the sag and damping position analysis, the amplitude and frequency of the dancing condition are analyzed; then the corresponding dynamic damping control strategy is proposed using the reverse equal pairing method.

[0088] The meaning of the reverse equal pairing method is: for each node that adds output, find a paired node that reduces output, and vice versa. The added and subtracted output values ​​of each paired node are equal. This ensures the power balance of the system, and the balancing machine only needs to bear the changes in the system network loss, which is generally very small, thereby avoiding the problem of output exceeding the limit that may occur in the balancing machine.

[0089] According to the reverse equal pairing method, when the oscillation source reduces the output, it is necessary to select a paired unit to increase the output. The selection principles are as follows:

[0090] (1) The correlation factor with the weak damping mode is small;

[0091] (2) The available active power margin is sufficient to meet the equal pairing requirements;

[0092] (3) The oscillation modes strongly associated with the unit have sufficient damping ratio.

[0093] S2: Installation of the anti-dance robot: installing the posture sensor on the transmission line, and fixing the anti-dance robot on the transmission line; the anti-dance robot includes a fixing module, a control module, an online monitoring module and a power supply module;

[0094] The fixing module is used to fix the anti-dance robot on the power transmission line;

[0095] The control module is used to receive feedback data and control the movement of the anti-dance robot;

[0096] The online monitoring module is used to collect pictures, video information, and the coordinate information of the current anti-dance robot, the coordinate information of the transmission line, and the coordinate information of the posture sensor on the transmission line;

[0097] The power supply module is used to supply power to the anti-dance robot;

[0098] Model of dual-branch online power supply:

[0099] The power obtained by the energy harvesting system is closely related to the current shunted into the energy harvesting branch. From the above analysis, it can be seen that this depends on the impedance of the damping branch. Therefore, it is necessary to study and analyze the damping branch. The magnetic core in the damping branch is equivalent to a transformer structure, with a single-turn coil on the primary side and an N-turn coil on the secondary side, and a matching capacitor with a capacitance of C is connected. According to the T-type equivalent circuit principle of the transformer, the equivalent circuit of the damping branch can be deduced as shown in Figure 6.

[0100] like Figure 6 As shown, R2′ is the resistance of the secondary coil converted to the primary side resistance, L l ' k2 is the converted leakage inductance; C′, R′ C They are the capacitance of the secondary side (under resonant state) converted to the capacitance of the primary side and the internal resistance of the capacitor, which can be easily deduced:

[0101]

[0102] If the number of turns of the secondary coil is large, for example, 20 turns, N 2That is 400, and the resistance R2 of the coil winding on the secondary side, and the leakage inductance L lk2 It is relatively small in itself, and after N conversion, it can be ignored. Secondly, the internal resistance of the capacitor is usually very small, and when matching capacitors, the equivalent internal resistance can be reduced by parallel connection, and N can be reduced in the same way. 2 times, which can also be ignored, so Figure 6 After equivalent simplification, Figure 7 As shown;

[0103] When the transmission line current remains unchanged, after the open core of the damping branch is selected, Figure 7 The excitation resistance R m ,Magnetic inductance L m ,The coil internal resistance R1 and L lk1 etc. are basically unchanged; assuming that the transmission line current is fixed, R1, L lk1 The influence of the excitation inductance L m Matching with the equivalent capacitance C', the circuit works in a resonant state, which can make the equivalent impedance Z of the damping branch d is the maximum value.

[0104] By analyzing the input impedance of the RLC parallel resonant circuit, we can deduce:

[0105]

[0106] Where Y d ′ is the input admittance of the parallel resonant circuit. By converting it to the capacitance value of the primary side and the internal resistance of the capacitor, it can be seen from the formula that when the capacitor C satisfies the formula derived by analyzing the input impedance of the RLC parallel resonant circuit, Z d The modulus of ′ has a maximum value;

[0107]

[0108] The quality factor Q of the parallel resonant circuit is:

[0109]

[0110] Can launch Z d The modulus of ′ is:

[0111]

[0112] According to Z d The modulus value of ′ can easily give the equivalent impedance Z of the damping branch. d The square of Q (quality factor) and the excitation resistance R mThe above analysis shows that the greater the equivalent impedance, the greater the output power that the energy-taking branch can obtain; therefore, when designing and selecting the open-type magnetic core of the damping branch, Z d The modulus formula of ′ is for reference.

[0113] From the analysis of the basic principle of the above energy extraction method, we can know that ignoring R1 and L lk1 When the damping branch works in the parallel resonance state, the circuit can be regarded as purely resistive, and the impedance of the damping branch is approximately Z d ≈Z d ′=R m (Q 2 +1);

[0114] In fact, the current on the transmission bus is basically determined by the load and is not affected by the online energy-drawing circuit. It can be approximately regarded as a strong current source with internal resistance together with the damping branch. At the same time, the energy-drawing branch can be approximately equivalent to R L The entire circuit can be simplified to Figure 8 As shown;

[0115] According to the maximum transfer theorem, when the impedance value of the circuit load is conjugate with the internal impedance of the power source (if it is purely resistive, the load is equal to the internal resistance), the load can obtain the maximum power. That is, when the impedance of the energy extraction branch is equal to the modulus of the internal resistance of the equivalent current source and the sum of the phase angles is zero, the maximum power will be obtained on the load impedance of the energy extraction branch.

[0116] When the current on the transmission line is approximately constant, the open core of the damping branch is selected, and the excitation inductance, leakage inductance and other parameters remain basically unchanged. The capacitor with a suitable capacitance value is matched to make the damping branch work in a parallel resonance state. It can be regarded as a pure resistive circuit, that is, the internal resistance Z of the equivalent current source d is purely resistive. Based on the above analysis, we only need to take the input equivalent impedance R of the energy branch L , and Z d If they are equal, the maximum output power can be obtained;

[0117] It can be deduced that under resonance, the maximum output power that can be obtained is:

[0118]

[0119] It can be seen from the formula that the maximum power is closely related to the quality factor Q and the impedance of the damping branch. When designing an open-type magnetic core, the quality factor should be increased as much as possible to increase the equivalent impedance of the damping branch to ensure that a sufficiently large output power can be obtained to supply the anti-dancing robot.

[0120] Core design and selection:

[0121] The core of the current transformer is usually made of several different core materials, and the physical properties of different materials are naturally different. Since the transmission lines have a wide range of differences from a few amperes to hundreds of amperes, it is particularly important to choose the core material. When the current on the cable is small, in order to obtain sufficient power for the monitoring equipment, the core is usually required to have the characteristics of high initial permeability and small starting current; when the current is large, the core is required not to enter a deep saturation working state, so as to avoid the voltage distortion on the secondary side into a high-amplitude peak wave that damages the entire circuit;

[0122] After the air gap is introduced into the open core, the relative magnetic permeability of the open core will drop significantly because the magnetic permeability of air is much lower than that of the magnetic material, so that under the same magnetic field strength, the core with air gap will not enter the deep saturation state; but the existence of the air gap will increase the starting current, so when selecting materials, materials with higher initial magnetic permeability should be selected.

[0123] Silicon steel sheets, Permalloy and nanocrystalline materials are currently the most widely used soft magnetic materials. The basic magnetic parameters of these three materials are shown in Table 4 below:

[0124]

[0125] As can be seen from the table, silicon steel sheets are made of steel with a low carbon content and pressed into thin sheets by adding silicon. The presence of silicon can increase the resistivity and has a higher saturation magnetic induction intensity. Compared with the other two, it is not easy to enter the saturation zone. However, the initial magnetic permeability of the magnetic material of silicon steel sheets is the lowest, and the iron loss under power frequency is also the highest;

[0126] Permalloy refers to a synthetic metal of iron and nickel, in which the nickel content is usually between 35% and 90% to meet different needs; Permalloy has high initial and maximum magnetic permeability, and low iron loss. At present, other elements such as tungsten and copper are added to the application of Permalloy to increase its resistivity; but its saturation magnetic induction intensity is relatively low, and saturation is very easy to occur;

[0127] The nanocrystalline core material has the advantages of the other two materials. Its initial and maximum magnetic permeabilities are similar to those of Permalloy, much higher than silicon steel sheets, and not easy to saturate. Due to its structural characteristics, it can effectively reduce eddy current losses, so the iron loss is the lowest among the three materials.

[0128] The magnetic core based on nanocrystalline material has a small starting current and a high saturation magnetic induction intensity. When made into an open-type magnetic core, it can meet the working conditions of hundreds of amperes of power transmission cable current without entering the saturation zone. Therefore, the present invention will use nanocrystalline as the magnetic core material of the damping branch open-type magnetic core.

[0129] At the energy extraction branch end, the rectifier circuit needs to be controlled so that the voltage phase and amplitude at the input end of the rectifier circuit can be controlled to maintain the parallel resonance of the circuit and adjust the equivalent impedance of the entire circuit, ultimately maintaining the maximum power output of the circuit. Therefore, how to control the voltage of the energy extraction branch is the top priority of the energy extraction method;

[0130] To design a sufficiently large damping branch input impedance and quality factor, the excitation inductance needs to be increased as much as possible. In addition to being designed with a larger magnetic permeability, the excitation inductance is also affected by the size of the magnetic core. Its size determines the maximum power that the power-taking system can obtain. In the above analysis, the excitation inductance can be enhanced by increasing the cross-sectional area and thickness of the open core to increase the output power obtained by the energy-taking branch. However, due to the limitations of the volume and weight of the energy-taking device, its size cannot be increased indefinitely.

[0131] At the energy extraction branch end, the rectifier circuit needs to be controlled so that the voltage phase and amplitude at the input end of the rectifier circuit can be controlled to maintain the parallel resonance of the circuit and adjust the equivalent impedance of the entire circuit, ultimately maintaining the maximum power output of the circuit; therefore, how to control the voltage of the energy extraction branch is the top priority of the energy extraction method, and the voltage tracking rectifier control circuit and control method will be studied and designed;

[0132] like Fig. 9 As shown, the online energy acquisition method control circuit includes four modules: current and voltage sampling module, MPPT algorithm control platform, current conversion voltage module, and voltage tracking rectification control circuit;

[0133] The current and voltage sampling module is used to obtain the DC voltage and current values ​​of the transformer secondary coil output after rectification. This value is used as the input data of the MPPT algorithm. According to the current and voltage values, the power change direction caused by the load change at the output end can be obtained. MPPT control platform, the paper selects ST company STM32F103C8T6 as the control platform to implement the MPPT control algorithm. According to the received voltage and current sampling signals, the output of the current conversion voltage module is controlled to be a voltage signal of different amplitudes. The voltage signal here is the same as the bus current phase. This signal is input into the voltage tracking rectifier control circuit, and finally adjusts the input voltage of the energy extraction branch, that is, the AC side voltage of the rectifier circuit.

[0134] S4: Anti-dancing robot test: Start the anti-dancing robot, attitude sensor and ground control station, and perform functional tests on the control module, online monitoring module and drive module on the anti-dancing robot to ensure complete functions;

[0135] S4: Record initial data: After the anti-dance robot test in S3 is completed, record the coordinates of the power transmission line, the coordinates of the anti-dance robot and the coordinates of the posture sensor;

[0136] S5: Principle of use: During use, the online monitoring module is used to collect the coordinates of the transmission line, the anti-dance robot, and the posture sensor in real time. The coordinate translation parameters and zero-degree image fitting parameters between the initial data are compared to calculate the dancing rotation data. The control module is used to control the movement of the anti-dance drone, change the center of gravity position and mass distribution of the transmission line, and achieve anti-dance.

[0137] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A control method for a power transmission line anti-dancing robot based on online power extraction, characterized in that: The steps include: S1: Establish a data model. Through experiments and data collection, establish a force model of the transmission line under the galloping state, and simultaneously establish an active anti-galloping model of dynamic damping control, that is, the influence and connection of different center of gravity positions and different mass distributions of the transmission line on the galloping amplitude and resonant frequency; S2: Installation of the anti-dance robot: installing the posture sensor on the transmission line, and fixing the anti-dance robot on the transmission line; the anti-dance robot includes a fixing module, a control module, an online monitoring module and a power supply module; The fixing module is used to fix the anti-dance robot on the power transmission line; The control module is used to receive feedback data and control the movement of the anti-dance robot; The online monitoring module is used to collect pictures, video information, and the coordinate information of the current anti-dance robot, the coordinate information of the transmission line, and the coordinate information of the posture sensor on the transmission line; The power supply module is used to supply power to the anti-dance robot; S4: Anti-dancing robot test: Start the anti-dancing robot, attitude sensor and ground control station, and perform functional tests on the control module, online monitoring module and drive module on the anti-dancing robot to ensure complete functions; S4: Record initial data: After the anti-dance robot test in S3 is completed, record the coordinates of the power transmission line, the coordinates of the anti-dance robot and the coordinates of the posture sensor; S5: Principle of use: During use, the online monitoring module is used to collect the coordinates of the transmission line, the anti-dance robot, and the posture sensor in real time. The coordinate translation parameters and zero-degree image fitting parameters between the initial data are compared to calculate the dancing rotation data. The control module is used to control the movement of the anti-dance drone, change the center of gravity position and mass distribution of the transmission line, and achieve anti-dance.

2. According to claim 1, a method for controlling a power transmission line anti-dancing robot based on online power supply is characterized in that: The distribution of the attitude sensors described in S1 is carried out at equal distances or at non-equidistant distances according to the stress characteristics of the conductors, so as to ensure comprehensive monitoring of the dancing of the long-distance transmission line.

3. The control method of a power transmission line anti-dancing robot based on online power supply according to claim 1 is characterized in that: The online power supply module described in S2 adopts a dual-branch online power supply system to power the anti-dancing robot; the dual-branch online power supply system includes a damping branch and an energy supply branch, and the damping branch and the energy supply branch are equivalent to a parallel relationship.

4. The control method of a power transmission line anti-dancing robot based on online power supply according to claim 3 is characterized in that: The damping branch includes a transmission bus, an open-type magnetic core, a coil winding and a capacitor. The open-type magnetic core material is a nanocrystalline magnetic core material. The magnetic core based on the nanocrystalline material has a small starting current and a high saturation magnetic induction intensity. The open-type magnetic core can meet the transmission cable current of hundreds of amperes without entering saturation.

5. The control method of a power transmission line anti-dancing robot based on online power supply according to claim 4 is characterized in that: The energy extraction branch includes a conductor, a transformer, a voltage tracking rectifier control circuit, a signal conversion circuit, an MPPT controller, a DC-DC circuit and an equivalent load of a monitoring device. The conductor is connected to the transmission bus and the primary side of the transformer using a clamp, and the secondary side of the transformer is connected to the subsequent processing circuit and the load.

6. The control method of a power transmission line anti-dancing robot based on online power supply according to claim 5 is characterized in that: The energy extraction circuit also includes a sampling module and a current conversion voltage module; the sampling module obtains the DC side voltage and current value of the rectified output of the secondary coil of the transformer, and controls the current conversion voltage module to output voltage signals of different amplitudes according to the value through the MPPT algorithm control platform, inputs the voltage tracking rectification control circuit, adjusts the input voltage of the energy extraction branch, maintains the circuit parallel resonance and maximum power output, and provides stable power for the robot.

7. The control method of a power transmission line anti-dancing robot based on online power supply according to claim 1 is characterized in that: The dancing rotation data described in S5 is a back-propagation neural network structure based on the BP algorithm. The power line dancing data processed by the neural network algorithm can identify the wire dancing state and extract the dancing frequency, amplitude and possible dancing area characteristic parameters by realizing nonlinear transformation from input to output.

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