53 results about "FIND Technology" patented technology

The invention provides a logistics cargo volume non-contact measurement method based on a computer binocular stereo vision technology and a point laser range finding technology. According to the method, a point laser range finding supplementary means is introduced; a point laser rangefinder is used to acquire the correspondence among the depth of a measurement point on a cargo object, the distance from an initial point and the point coordinate on an image; the incidence relationship between geometric projections of images shot by left and right cameras is established; the geometric projection correlation area of corresponding feature points in left and right images is positioned and set; image stereo matching of left and right image feature points is carried out in the set geometric projection correlation area of the corresponding feature points; and full width feature point extraction is carried out on the left image, which greatly reduces the range of image matching search and the calculation cost. According to the invention, the problem of the uniqueness of the solution of a spatial point reduction problem is solved; the problems of mis-matching and leakage matching in the image matching process are avoided; and the validity and the accuracy of image stereo matching are greatly improved; and the accuracy and the speed of the measurement of a binocular stereo vision system are improved.

The invention discloses a direction finding method for a three-channel spatial spectrum estimation direction finding system. The system comprises a direction finding antenna array, three common-frequency multi-channel receivers and a direction finding algorithm processor, wherein the direction finding antenna array is a 9-element uniform circular array and is provided with an antenna select switch for selecting different antenna elements in the antenna array; three antennas are selected by the antenna select switch each time, wherein the No. 1 antenna is required to be selected each time; 1, 2 and 9, 1, 3 and 8, 1, 4 and 7, and 1, 5 and 6 are selected, wherein each number represents the number of the selected antenna, and the four groups of antennas are alternately selected; the direction finding receivers are of three-channel; and three antennas selected by the antenna switch each time are connected with the three common-frequency multi-channel receivers respectively. By researching the spatial spectrum estimation direction finding technology and improving an MUSIC direction finding algorithm, receiving channels are reduced under the condition of not reducing the antenna elements; meanwhile, the direction finding performance is guaranteed to be unchanged; and the aims of lowering the cost of the direction finding equipment and improving the reliability of the equipment are fulfilled.

The invention relates to the range finding technology based on target tracking and recognizing and particularly relates to a range finding device and a range finding method based on target tracking and recognizing by a photoelectric intelligent sensing platform. The technical problem that target lock-on is difficult when a dynamic target is range-found to cause inaccurate measurement at present is solved. The range finding device based on target tracking and recognizing by a photoelectric intelligent sensing platform comprises a photoelectric intelligent sensing platform, an image acquisition module and a central processor. The photoelectric intelligent sensing platform includes a tripod head with a built-in CPU, and a laser range finder arranged on the tripod head; the image acquisition module is also arranged on the tripod head; signal output ends of the tripod head, the image acquisition module and the laser range finder are connected with signal input ends of the central processor; and signal input ends of the tripod head, the image acquisition module and the laser range finder are connected with signal output ends of the central processor. The device and the method of the invention have strong effectiveness and high real-time performance in target tracking and locating.

The invention relates to the field of radiolocation direction-finding systems, and aims to provide a single-channel radiolocation direction-finding system and a direction-finding method thereof to reduce cost and improve direction-finding accuracy. The single-channel radiolocation direction-finding system is characterized by comprising a direction-finding antenna array, a single-channel receiver with the functions of filtration, amplification, frequency conversion and amplitude limitation, and a direction-finding microprocessor for A / D sampling and digital signal processing, wherein the direction-finding antenna array mainly comprises N identical antenna units which are arranged on the circumference of a concentric circle, wherein N is greater than or equal to 3; and each antenna unit is connected with the single-channel receiver through a radio-frequency electronic switch. The invention utilizes a single-channel radio direction-finding technology combined with a phase interference method and a Doppler direction-finding principle, and only needs one single-channel receiver with the functions of filtration, amplification, frequency conversion and amplitude limitation, thereby reducing the complexity and the cost of equipment, improving reliability, reducing the calculated amount of back-end signal processing, and improving direction-finding accuracy.

The invention discloses a mobile anchor node based weighted centroid locating method for a wireless sensor network node and belongs to the field of application of the wireless sensor network and the random mobile technology and the wireless range finding technology. Since a mobile anchor node is utilized to substitute for a traditional anchor node, usage cost is reduced, and coverage rate for unknown nodes is increased. Locations of the unknown nodes can be obtained by scheduling moving path of the anchor node and by the aid of the weighted centroid algorithm. The mobile anchor node based weighted centroid locating method for the wireless sensor network node is low in cost, simple in algorithm, high in coverage rate of unknown nodes, accurate in locating, and applicable to practical use.

The invention relates to the technical field of food detection, and in particular relates to a nondestructive testing system for viscoelasticity of livestock and poultry meat. The system comprises an air source device, a control device, a laser position finder and a computer, wherein the air source device is used for outputting airflow to the surface of a to-be-tested sample through a gas pipeline; the control device comprises a single chip microcomputer and a plurality of valve bodies which are connected with the single chip microcomputer; the valve bodies are arranged on the gas pipeline; the laser position finder is connected with a sensing head; the sensing head is used for collecting displacement information of the surface of the to-be-tested sample and feeding back to the single chip microcomputer; and the computer is connected with the single chip microcomputer, and is used for processing and analyzing the displacement information. According to the nondestructive testing system, noncontact action force is formed on the surface of the to-be-tested sample through the air source device; the action time of the airflow and control on air pressure are achieved by the single chip microcomputer and the plurality of valve bodies; airflow pulse is effectively combined with a laser range finding technology, so that the action of nondestructive testing of the viscoelasticity of the livestock and poultry meat is achieved.

The invention relates to the direction finding technology of the broadband array signal processing field. The array direction-finding method of the invention comprises steps of choosing a focusing reference frequency point, decomposing an OFDM signal received by an array and performing DFT processing to obtain a broadband array signal, using a constraint condition that an error between an array flow pattern after focusing and a reference frequency point array flow pattern and an array flow pattern matrix to calculate a focusing matrix corresponding to a frequency point, performing focusing conversion on array reception data in every sub-time-frame to obtain a single frequency point data covariance matrix according to the focusing matrix so as to obtain a covariance matrix relating to the reference frequency point, calculating a mathematic mean value R of each reference frequency point covariance matrix, performing characteristic value decomposing on the R to obtain a signal sub-space and a noise sub-space so as to obtain a space spectrum expression of a broadband MUSIC algorithm and performing searching according to a space spectrum expression to obtain an angle position corresponding to P maximum value points which is an estimation value of a direction of a broadband OFDM signal incoming wave.

The invention provides a berthing assist system and method based on binocular stereoscopic vision. The system is composed of a data collection platform and a data processing platform. The data collection platform comprises a data collection module, and the data collection module composed of a binocular camera and an embedded processor realizes the function of data collection. The data processing platform comprises a data processing module, a data storage module and a data transmission module, and the data processing platform uses an industrial control computer or a high-performance embedded device to realize functions of the data processing, storage and processing modules. Binocular (left and right) images, the contour of a harbor, the distance / angle between a ship and the harbor and early warning information are transmitted to an external client in a wired or wireless manner to assist berthing, or transmitted to a display terminal to help safe work of a ship operator. The range finding technology based on stereoscopic vision is low in cost, and abundant environment information can be obtained.

A fishing bait delivery system is disclosed. The system has a remotely controlled bait delivery vehicle, a fishing pole assembly, and a remote control for controlling bait delivery vehicle. The bait delivery vehicle has a fishing bait holder that holds a baited end of a fishing line until the baited end is released at a desired location. The fishing bait is secured to the fishing pole assembly via the fishing line. The fishing pole assembly is made up of a conventional fishing rod and reel. The fishing bait can be natural, living or deceased, or artificial. For live bait, the bait delivery vehicle can include a live bait well. In various embodiments the release of fishing bait may be automated. The system can use fish finding technology, wherein the bait delivery vehicle includes a fish finding sensor which transmits data to a fish finder viewer.

The invention discloses an interferometer direction finding method based on the Chinese remainder theorem, which relates to an interferometer direction finding technology in the field of radio direction finding. In the case that the antenna shape and array size are fixed, the present invention uses the Chinese remainder theorem to design an antenna array form with the best performance, which solves the phase ambiguity problem; and adopts long and short baseline matching step by step and virtual array processing technology to effectively expand the The equivalent baseline length improves the accuracy of direction finding. The equipment manufactured by the invention has the advantages of simple operation, reliable performance, convenient algorithm, high precision of direction finding and the like. It is especially suitable for accurate direction finding and positioning for radiation sources such as communication, radar, and measurement and control in the detection equipment in the field of military electronic countermeasures.

The invention belongs to the linear frequency-modulated continuous-wave radar range finding technology, relating to a frequency-modulated continuous-wave radar level gauge. The level gauge comprises an antenna module, a transmit-receive unit, a circulator, a power supply module, a processing unit and a display unit. An FMCW signal generated by a frequency synthesizer of the transmit-receive unit is subjected to frequency conversion to obtain K wave band to form a K wave-band signal with power no less than 5mw. The K wave-band signal is outwardly radiated to the antenna module via the circulator. An echo signal is conveyed to the transmit-receive unit when the antenna module receives the circulator. The transmit-receive unit is used for performing harmonic mixing operation and band-pass filtering operation and amplifying the echo signal to output a difference frequency signal containing distance information and forms a digital signal by A / D sampling. The processing unit is used for reconvening the difference frequency signal of the transmit-receive unit to carry out FFT treatment, clutter rejection, target detection and spectrum estimation in order to obtain liquid level data. The technical scheme helps to improve precision of liquid level detection.

The invention discloses a fault traveling wave filtering method based on characteristic point identification and linear interpolation, and the method improves the practicality of the power distribution network single-phase grounding fault range finding technology based on HHT. The method comprises the steps: collecting three-phase voltage traveling wave signals of a fault point upstream M end anda fault point downstream N end through a voltage transformer after a fault; carrying out the phase-mode transformation, and obtaining a linear mode voltage traveling wave; carrying out the filtering of the linear mode voltage traveling wave through a filtering algorithm based on the characteristic point identification and linear interpolation; and finally carrying out the fault range finding through a double-end traveling wave range finding method based on HHT. The method can effectively filter the noise in the actual measurement fault voltage traveling signal, and solves a problem that the arrival time of the head of a disturbed traveling wave is not accurate during HHT calibration.

The invention relates to the fields of a broadband full-polarized antenna array sensor device and a direction finding technology thereof, and especially to a full-polarized interferometer based on spatial sampling antenna array and a parameter estimation method of the interferometer, and the interferometer is used radio systems as radars and communication. The interferometer is characterized by using a six-unit ultra-wide-band linear polarization antenna array, two types of ultra-wide-band linear polarization antennas, namely ultra-wide-band log-periodic antennas and ultra-wide-band Vivaldi antennas are included, and the ultra-wide-band log-periodic antennas correspond radiation of a current source and the ultra-wide-band Vivaldi antennas correspond to radiation of a magnetic current source to reduce electromagnetic coupling among the units; and the amount of antenna units is 6, each antenna unit is of a linear-polarization antenna form, the units form a ring array, the six units of linear-polarization antennas are arranged in the radial manner according to a circular center, and the antenna units have spatial orientations different from one another. The interferometer and the parameter estimation method are suitable for spaceborne, airborne, missile-borne and other radio direction-finding systems, parameter measuring functions are more comprehensive, and the platform adaptability is higher.

The invention discloses a six-degree-of-freedom nanometer-displacement-bench calibrating device based on light splitting laser interference and belongs to the laser precision range finding technology field. The device comprises a supporting platform, a light splitting measurement apparatus system and a nanometer displacement bench. Through the above design, nanometer-moving-platform six-degree-of-freedom attitude measurement is guaranteed; an any attitude nanometer scale displacement measurement problem is solved; and the device is suitable for all-attitude identification and ultra-precision measurement calibration of a nanometer-displacement-bench simultaneous change of an X axis, a Y axis, a Z axis and a rotation angle.

The invention relates to a two-cable-section mixing direct current power transmission line fault section identification method based on mode identification, and belongs to the electric power system fault range finding technology field. When two sections of cables are mixed and a direct current power transmission line is out of order, an absolute value of fault pole voltage travelling wave data obtained at a cable measuring end is calculated, normalization processing is carried out, and discrimination of a cable mixing direct current power transmission line fault section is determined by utilization of a principal component clustering analysis method. The fault section is discriminated according to plus or minus of a projection q1 value of the voltage initial fault traveling wave on the first principal component (PC1) shaft, if the sign of the projection value q1 is positive, the overhead line fault is determined; otherwise, the cable line fault is determined. Principal component clustering analysis is carried out by utilization of the absolute value of the fault pole voltage, influences of fault line polarity to fault section discrimination are avoided effectively, the principle is simple, and the method is reliable and effective.

The invention discloses a self-adaptive monopulse direction finding method under combined constraint conditions and belongs to a monopulse direction finding technology of the self-adaptive array signal processing field. The problem of reduction of estimated performance of monopulse in the presence of interference, so that the monopulse performance is improved. Based on the processing process, thecomplexity of time calculation is improved while the optimal weight vector is solved through enlargement of dimensionality, and the combined constraint conditions are equivalent to conventional linearconstraint conditions and have the performance superior to the conventional linear constraint conditions. The method is very close to conventional static-state monopulse, and the monopulse performance is effectively improved. Moreover, compared with conventional monopulse angle measuring methods, the method has the advantages of being small in signal to noise ratio, low in time complexity, high in accuracy and more stable through full utilization of overall processing modes of narrow-band signals. Therefore, the method has higher engineering practicability.

The invention relates to a rapid anti-disturbance north finding instrument based on a transposition north finding technology, which relates to a north finding instrument, in particular to a rapid high-precision north finding instrument for vehicle orientation. The invention aims at providing a rapid anti-disturbance north finding instrument based on the transposition north finding technology, which is simple in structure, fewer in measuring errors, short in measuring time, not afraid of external disturbance and long in service life. The rapid anti-disturbance north finding instrument based on the transposition north finding technology comprises a three-axis IMU (inertial measurement unit) assembly (21), an I / F (current / frequency) plate (4) and a main control board (3), wherein the three-axis IMU assembly (21) is fixed on a rotor of a transposition device (2), the three-axis IMU assembly (21) consists of a three-axis laser gyroscope and a three-axis accelerometer, a signal is transmitted by the I / F plate (4) to the main control board (3), the main control board (3) adopts an architecture of DSP (digital signal processor) and FPGA (field programmable gate array), and the main control board (3) is used for receiving a north finding instruction, calculating a transposition north finding algorithm, acquiring data and controlling peripheral equipment.

The invention discloses a digital multi-beam angle-measuring method and system based on a single receiving channel. Direction-finding antennas share a receiving channel and an A / D acquisition and storage unit; received signals of the antennas are sampled in sequence through a radio-frequency switch at the same time interval; a plurality of receiving beams are formed in a digital domain for array receiving data constructed by repeated rotational sampling; and then passive high-accuracy angle measurement for a non-cooperative target radiation source by adopting sum and difference beam angle measurement. Compared with a multi-receiving-channel direction-finding system, the digital multi-beam angle-measuring system has remarkable advantages on the aspects of cost and system complexity, and degradation of the direction-finding performance due to inconsistent amplitude phases between channels is avoided. Compared with a classic super-resolution spatial spectrum direction-finding technology,the digital multi-beam angle-measuring system has higher receiving sensitivity, is particularly suitable for detecting weak power signals such as various sky waves, scattering and sidelobe, and meetsthe demand of beyond visual range detection. Only multiplication and addition operations are used in the multi-beam forming and angle measurement process, and the feature decomposition and the spectrum peak search operation of a large-scale data matrix are not involved, so that both the real-time performance and the accuracy are ensured.

The invention discloses a material pile measuring system based on laser range finding technology, and the material pile measuring system based on laser range finding technology can be used for accurately measuring the volume and the number of material piles. When the material pile measuring system based on the laser range finding technology is used, a holder is fixed to the top of a material pile warehouse, a laser range finder is used for scanning the material pile warehouse, an angle measurer is used for recording angles during measurement, data measured by the laser range finder and the angle measurer are transmitted to a PC client and a data receiving and storing module through a data transmission module, the PC client is used for calculating the volume and the number of material piles through data integration, and sending the result of calculation to the data receiving and storing module to be stored. Operators can conveniently check data, the shape of material piles can be accurately measured through laser scanning and range finding, so that the volume and the number of the material piles can be accurately measured, the whole measurement can be automatically completed, time and labor can be saved. The material pile measuring system based on the laser range finding technology is suitable for popularization and application in the field of measurement of material piles.

The invention provides a least square direction finding method based on the time difference of arrival of sound signals. The basic idea is that an absolute value type cost function is adopted when a Lagrange multiplier is solved so as to enable the Lagrange multiplier to have a clear expression; the standard sound velocity is adopted to replace the measured sound velocity when the Lagrange multiplier is calculated, so that the whole direction finding process is independent of the sound velocity; and rough direction estimation for a sound source is acquired by adopting a linear least square direction finding technology to serve as a judgment basis when the Lagrange multiplier is calculated. Compared with the prior art, the beneficial effects lie in that the direction finding method providedby the invention is better than the traditional estimation method in terms of the accuracy of azimuth angle and pitch angle estimation and is more excellent in accuracy of pitch angle estimation.

The embodiment of the invention discloses a traffic safety prompt method and device based on an intelligent terminal. The method comprises the steps: enabling the intelligent terminal to obtain a vehicle front view image of a current running vehicle through a camera device of the intelligent terminal; obtaining the distance between a barrier and the current running vehicle through employing the video range finding technology; displaying prompt information to a user if the distance between the barrier and the current running vehicle is less than or equal to a current safety distance. Therefore, the method reminds the user of keeping a certain distance with a front barrier (a front vehicle) through the commonly-used intelligent terminal, thereby effectively reducing the potential safety hazards of driving, and reducing the driving risks.

The invention relates to a range finding method based on laser pulse shape leading edge detection and a system thereof and belongs to the laser pulse range finding technology field. In the invention, a high speed ADC is used to sample a reference wave and an echo of a pulse signal. A simulation waveform is converted into a digital waveform signal. And then a digital signal processing mode is used to carry out echo time delay calculating so that a distance is calculated. When a laser pulse range finding mode is used to carry out object outline scanning and during a high-speed dynamic scanning process, monopulse echo range finding precision is increased and high-precision outline scanning is realized.

A traceable synchronous measurement ruler-based mixed double-light source laser range finding device and method belongs to the technology of phase laser range finding. The range finding device comprises a measurement ruler generation unit, a laser frequency shift unit, abeam expanding collimating mirror set, a measurement optical path and a circuit unit. The range finding method comprises a step 1 of starting a frequency reference laser and a double longitudinal mode frequency stabilization He-Ne laser, a step 2 of taking one beam as a reference laser beam, and another beam as a measurement beam, a step 3 of taking a formula defined in the specification as an accurate measurement ruler, a step 4 of taking a formula defined in the specification as a rough measurement ruler, and a step 5 of moving a measurement cube-corner prism to a target end for obtaining phase differences of the accurate measurement ruler and the rough measurement ruler Phi 1 and Phi 2 respectively and obtaining a to-be-tested distance value through a formula. The invention solves a problem that a device and method for achieving large power, synchronism of multiple measurement rulers and traceability is not available in the phase laser range finding technology, and the device and method provided by the invention is characterized by being high in range finding precision and measurement efficiency, and good in stability and real-time performance.

The invention provides an online detection device and detection method for rolling reduction of a stirring head. The online detection device comprises a temperature control box, a distance measurementdevice, an industrial personal computer and two temperature control devices, wherein the distance measurement device and the temperature control devices are connected with the industrial personal computer in a two-way communication mode; the distance measurement device comprises a first laser range finder and a second laser range finder; the first temperature control device comprises a first temperature sensor and a first temperature adjusting module; the second temperature control device comprises a second temperature sensor and a second temperature adjusting module; and the first temperature adjusting module and the second temperature adjusting module each comprise a semiconductor chilling plate, a microcontroller and a peripheral circuit. A detection system performs online measurementon the rolling reduction of the stirring head in the welding process by utilizing a triangle laser range finding technology, changes of the welding pressure can be mastered through real-time detectionof the rolling reduction of the stirring head, accordingly, effective control over the welding pressure is further achieved, and the welding quality is improved.

The invention discloses a north finding method of ARMA time sequence based on an optical fiber gyro. Before the process of data processing, the invention analyzes the output sequence of a plurality of optical fiber gyros with different models in a north finding system to determine that for the series of numbers in the original series of numbers, which goes through random stationarity processing, the fitting of ARMA (2, 1) model can be implemented with the best effect; therefore, the invention proposes the establishment of an output model of a north finding testing fiber gyro by using ARMA and offers a whole proposal of parameter solving and model building. First, the proposal reduces the error of the north finding model fitting, thus leading the fitted model to be closer to the property of original series of numbers. The model has higher accuracy and certain university in the north finding technology and provides a foundation for the application of subsequent filter methods such as kalman filter which needs relatively accurate north finding models and the like. In addition, in regard to the solving of model parameters, fixed solving steps and the establishment method of a model of the original series of numbers are proposed, thus improving the speed and efficiency of data processing in the north finding testing.

The invention discloses a method and device for separating and extracting multiple signals, and relates to a method and device for direction finding, digital beam forming, signal separation, automatic identification and continuous demodulation of multiple signals in the field of communication reconnaissance. It consists of antenna array, antenna switch array, nine-channel receiver, post-processing module, multi-signal separation and demodulation module, power supply and other components. It uses the spatial spectrum estimation and direction-finding technology based on array signal processing to obtain the direction of arrival of electromagnetic signals, calculates weighted vectors and sets hardware devices through digital beamforming and blind beamforming methods, so as to detect multiple signals of the same frequency or different frequencies arriving at the same time. The signal is filtered in the spatial domain, and the separated multi-channel signals are automatically identified and continuously demodulated and output. It has the characteristics of high interference suppression, fast processing speed, low cost, convenient operation and maintenance, etc. It is especially suitable for multi-signal separation and extraction devices in communication countermeasures, intelligence reconnaissance, radio monitoring and other occasions.

The disclosure relates to a large-scene binocular range finding and correction method in overhead power transmission channel image monitoring. The method comprises the following steps: (1) calibratinga binocular camera by using a calibration rod method in a long-distance large-scene field view condition; (2) scaling down an image to correct a calibrated focal length parameter in order to reduce afocal length difference between two cameras; and (3) searching out an optimal rotation angle of a three-dimensional coordinate system by using a quasi-Newton method so that a camera coordinate systemcoincides with a ground coordinate system as much as possible. The method can solve the calibrating difficulty of a traditional binocular range finding technology in an overhead line channel large scene, and reduces a calibrated focal length difference by scaling down the image, can solve the focal length difference due to the limitations of the camera setting itself and the mechanical precision,provides the algorithm for searching out the optimal rotation angle of the three-dimensional reconstructed coordinate system by using the quasi-Newton method, and can solve the unclear or obscured boundary textures at the bottom of an object.

A fishing bait delivery system is disclosed. The system has a remotely controlled bait delivery vehicle, a fishing pole assembly, and a remote control for controlling bait delivery vehicle. The bait delivery vehicle has a fishing bait holder that holds a baited end of a fishing line until the baited end is released at a desired location. The fishing bait is secured to the fishing pole assembly via the fishing line. The fishing pole assembly is made up of a conventional fishing rod and reel. The fishing bait can be natural, living or deceased, or artificial. For live bait, the bait delivery vehicle can include a live bait well. In various embodiments the release of fishing bait may be automated. The system can use fish finding technology, wherein the bait delivery vehicle includes a fish finding sensor which transmits data to a fish finder viewer.

The invention is suitable for the laser range finding technology field and provides a three-dimensional laser radar range finding method and device, and a terminal device. The method comprises the following steps of sending a control signal according to a preset range finding period, and obtaining a range finding result of each range finding channel, wherein the control signal is used to make a laser emitting device generate a pulse laser so as to successively carry out range finding on each range finding channel; calculating a predicted wave peak phase of a laser echo of each range finding channel according to a range finding result of each range finding channel and a preset fuzzy control rule; and according to the predicted wave peak phase of the laser echo of each range finding channel, determining a dynamic range finding period of next range finding of each range finding channel. In the invention, the dynamic range finding period can be adopted to carry out range finding in the next range finding, which solves a problem of idle part time in the range finding period, saves range finding time and improves range finding efficiency.

The invention relates to a fault branch identification method of three-terminal direct-current power-transmission-line discrete wavelet transformation and a support vector machine and belongs to the electric power system fault range finding technology field. The method is characterized by setting fault positions in a three-terminal direct-current MT branch, an NT branch and a QT branch, setting a step length to be 1km and transition resistors to be 0omega, 10omega and 100omega respectively; secondly, defining a time window length to be 1ms, carrying out db4 wavelet decomposition on a measurement terminal current traveling wave, selecting a wavelet transformation coefficient under a second scale as an input attribute of the support vector machine SVM, establishing a SVM fault branch discrimination model, training the model, and defining that SVM output 1 is a QT branch fault, output 0 is a MT branch fault and output -1 is an NT branch fault; and finally, when a three-terminal direct-current line is generated, carrying out db4 wavelet decomposition on the current traveling wave and inputting the SVM, and according to an output result of the SVM, realizing determination of the fault branch.