52results about How to "Fast ranging speed" patented technology

The invention relates to the technical field of high-precision and low-consumption radar distance measurement, comprising a Hart module, a measuring module and a measuring line. The distance measurement of the system is based on TDR principle, adopting double DDS to generate two-way precise timing clock and realizing amplified time proportion of echo pulse, with a distance measuring precision of 5 mm; ultra wideband narrow pulse signal realizes high resolution of distance measurement, with a resolution of 1 mm; the proposal for working at intervals of the system greatly reduces power consumption which is 40 mW, in accordance with industrial standard of intrinsic safety.

The invention relates to a method for rapidly measuring a distance between multiple moving objects based on machine vision. The method comprises the following steps: fitting a ground truth box in an image training set and actual distance, storing a distance measuring model, performing height extraction on a bounding box generated by a specific target by a real-time detection algorithm SSD (singleshot multibox detector) and inputting into the distance measuring model so as to acquire the measuring distance between multiple objects. According to the multi-moving-object rapid identification anddistance measurement method, the specific multiple objects can be subjected to identification and distance measurement efficiently in real time. Compared with other ETA (electronic travel aids) distance-measuring systems, the method is more practical and has a good application prospect and an application value of actual engineering.

The invention provides a correlation sampling based laser multi-pulse ranging system, relating to a laser ranging system. The correlation sampling based laser multi-pulse ranging system is provided with a clock control circuit module, a laser pulse transmitting module, a laser pulse receiving module and a time information processing module, wherein the clock control circuit module is provided with two clock signal output ends and is provided with a local oscillator, a first frequency divider, a second frequency divider, a first mono-stability trigger and a second mono-stability trigger; the laser pulse transmitting module is provided with a pulse driving circuit, a semiconductor laser, an opto-isolator and a collimating lens; the laser pulse receiving module is provided with an avalanche photodiode, a pre-filtering amplifying circuit, an opto-isolator and a focusing lens; and the time information processing module is provided with a first sample holding circuit and a second sample holding circuit. A sampling signal is subjected to frequency doubling, the sampling time of transmitting pulse and receiving pulse is reduced, the ranging speed is increased, the measurement precision is improved, and the correlation sampling based laser multi-pulse ranging system can solve the problem of low precision in a short-range laser ranging mode.

The present invention discloses a laser distance measurement method and device. The method comprises: emitting laser signals having light intensity modulated by semi-continuous period square wave; receiving echo optical signals reflected by a target and employing a photoelectric detector to convert the echo optical signals to electric signals; filtering low-frequency components of the electric signals through high-pass filtering, and moving the voltage neutral point modulated by the square wave to a zero point to solve the interference of the echo amplitude variation in the distance measurement; inputting the signals mentioned above to a voltage comparison module to obtain a plurality of overturning signals; and measuring the time difference from the beginning of the distance measurement to each overturning signal, obtaining multiple measurement results of the flight time of the semi-continuous square wave optical signals after each time difference is corrected according to the square wave signal period, and obtaining the accurate distance information after average. The laser distance measurement method has no ranging limitation and has fast laser distance speed and simple realization, can fully utilize the performance advantages of the laser under the square wave modulation, and can construct high-performance and multi-channel laser distance measurement system.

The invention discloses a laser ranging method and a laser ranging device utilizing semi-continuous square wave modulation and flight time measurement. The laser ranging method comprises the steps of transmitting a laser signal of which the light strength is modulated by a continuous periodic square wave, receiving an echo optical signal which is reflected by an object, and converting the echo optical signal to an electric signal by means of a photoelectric detector, filtering a low-frequency component through high-pass filtering and moving a voltage middle-position point which is modulated by a square wave to a zero point for settling interference of echo amplitude change to ranging, then inputting the signal into a voltage comparison module for obtaining a plurality of turning signals, measuring a time difference between ranging starting and each turning signal, correcting each time difference according to a square wave signal period for obtaining a plurality of measurement results on flight time of the square wave optical signal, and obtaining accurate distance information after averaging. The laser ranging method has advantages of no measurement range limitation, high ranging speed, easy realization, etc. Performance advantages of a laser in square wave modulation can be sufficiently utilized for constructing a laser ranging system with high performance and multiple channels.

The invention relates to a vehicle door unlocking method, device and system, electronic equipment and a storage medium. The method comprises the steps of continuously obtaining the distance between anobject outside a vehicle and an infrared distance measuring sensor through the infrared distance measuring sensor arranged outside the vehicle; in response to the fact that the distance is graduallyreduced and the duration that the distance is smaller than or equal to a first distance threshold value reaches a first duration threshold value, awakening and controlling an image collection module arranged on the vehicle to acquire a video stream; or, in response to the fact that the distance is gradually reduced and the distance is maintained for a fixed duration reaching a second duration threshold in the process that the distance is smaller than or equal to the second distance threshold, awakening and controlling the image collection module to acquire a video stream; performing face recognition based on at least one image in the video stream; and in response to successful face recognition, controlling at least one vehicle door of the vehicle to be unlocked and / or opened.

The invention discloses a microwave distance measuring device based on relative sampling, and relates to a microwave distance measuring device. The invention provides a microwave distance measuring device based on relative sampling, which has the advantages of simple structure, high precision and low cost. The device is provided with a frequency control module, a microwave module and a signal processing module, wherein the frequency control module is provided with a main clock signal generator, a main path pulse forming circuit, a sampling clock signal generator and a sampling pulse forming circuit; the microwave module is provided with a local oscillator, a main path switch, a sampling switch, a power amplifier, a low noise amplifier, a filter, a coupler, a transmitting frequency mixer, a receiving frequency mixer and an antenna; and the signal processing module is provided with a transmitting peak value detector, a receiving peak value detector, an OR gate circuit, a microcontroller and a display. By the sampling signal, of which the period is nearly equal to that of the receiving signal, the relation-based sampling of the transmitting signal and the receiving signal is carried out, so that the expansion of the time difference between the transmitting signal and the receiving signal on the time domain is realized, and the highly precise object distance measurement is achieved.

The invention discloses a range finding method and a range finding device based on a binocular video. The range finding method comprises the steps of acquiring a binocular image; performing preprocessing on the binocular image; finding a corresponding point which matches each pixel point from the binocular image through a stereo matching algorithm, calculating a parallax of each pixel point of the binocular image and obtaining a parallax graph; setting a sample set and initializing the sample set by means of a processed first parallax frame; performing parallax optimization and target extraction on the current parallax frame by means of the sample set, and updating the sample set, and utilizing the sample set in parallax optimization and target extraction on a next parallax frame; calculating the average value of parallaxes of all pixel points of a target extracted from the current parallax frame, and calculating for obtaining a distance to the target according to a binocular range finding algorithm. According to the range finding method and the range finding device, after the parallax graph is acquired through the stereo matching algorithm, algorithm precision is improved through processing of multiple frames, and furthermore the target is effectively extracted. The range finding method and the range finding device can settle a problem of incapability of simultaneously realizing high efficiency and high precision.

The invention discloses a method for ranging a single-phase earth fault of a line by using single-end electric quantity. The method comprises the steps of measuring the fault phase voltage, the fault phase negative sequence current, the fault phase current and the zero sequence current in a transmission line protection mounting location; calculating an imaginary part of the ratio between the fault phase voltage and the fault phase negative sequence current; calculating an imaginary part of the ratio between potential drop per unit length of the transmission line and the fault phase negative sequence current; and dividing the imaginary part of the ratio between the fault phase voltage and the fault phase negative sequence current by the imaginary part of the ratio between the potential drop per unit length of the transmission line and the fault phase negative sequence current to obtain the fault distance from the transmission line protection mounting location to the single-phase earth fault point. The method uses the single-end electric quantity to achieve accurate measurement of the single-phase earth fault distance of the transmission line, overcomes the influence of transition resistance and load current on the fault distance measuring accuracy, the ranging principle is simple, the program is easy to achieve, and the method has the advantages of small calculation amount, high ranging speed and high real-time performance.

The invention discloses a line single-phase ground fault single-terminal location method capable of preventing influences of both transitional resistance and load current. According to the method, the voltage phase angle of a single-phase ground fault point is calculated by utilizing the fault-phase negative sequence voltage of the relay location of a transmission line and the positive sequence impedance of the transmission line per unit length; the imaginary part of the voltage drop from the relay location of the transmission line to the single-phase ground fault point is calculated according to the characteristic that the voltage along the transmission line is in linear monotone decreasing; and the imaginary part of the voltage drop from the relay location of the transmission line to the single-phase ground fault point is divided by the imaginary part of the voltage drop of the transmission line per unit length to obtain the fault location. The line single-phase ground fault single-terminal location method solves the problem that the transitional resistance and the load current influence the single-terminal fault location precision, is high in single-terminal location precision, simple in location principle and easy in program implementation, and does not need to adopt the search algorithm, so that direct calculation of the fault location is realized, location speed is quick and the real-time performance is strong.

The invention discloses a line single-phase earthing fault single-end ranging method realized by utilizing voltage drop imaginary part characteristics. The method utilizes the fault phase negative sequence voltage and the transmission line positive sequence impedance per unit length to calculate the single-phase earthing fault point voltage phase angle, and further calculate an additional fault distance caused by a transition resistance, and the imaginary part of the ratio of the fault phase voltage to the zero sequence compensating current divides the imaginary part of the transmission line positive sequence impedance per unit length and then subtracts the additional fault distance to obtain a fault distance between the transmission line protection mounting part and the single-phase earthing fault point. The method provided by the invention overcomes the impact defects of the transition resistance and load current on single-end fault ranging precision, the ranging precision is high when the transmission line has a single-phase high resistance earthing fault, the ranging principle is simple, the program is easily realized, the fault distance is directly calculated without using a search algorithm, the ranging speed is quick, and the real-time is strong.

The invention discloses a line single-phase earth fault single-terminal ranging method implemented by the aid of sequence components. The line single-phase earth fault single-terminal ranging method includes converting negative-sequence voltages of a power transmission line single-phase earth fault point into an equivalent zero-sequence voltage; accurately computing the fault distance according to a fault characteristic that a certain zero-sequence voltage of a power transmission line single-phase earth fault point is equal to the equivalent zero-sequence voltage so as to implement power transmission line single-phase earth fault single-terminal ranging. The line single-phase earth fault single-terminal ranging method has the advantages that the power transmission line single-phase earth fault single-terminal ranging is implemented according to distribution characteristics of the zero-sequence voltages along a power transmission line, influence of transition resistance on the ranging precision is eliminated in principle, influence of load currents and fault positions is prevented, and the ranging precision is high; a ranging principle of the method is simple, programs are easy to implement, the fault distance does not need to be directly computed by a search algorithm, and the method is high in ranging speed and instantaneity.

The invention discloses an electric transmission line phase fault single-ended distance measuring method. The electric transmission line phase fault single-ended distance measuring method includes the following steps of working out equivalent resistance through the voltage between fault phases, the current between the fault phases, and the negative-sequence current between the fault phases at the electric transmission line relay location, obtaining the voltage of a phase fault point through the fact that the equivalent resistance is multiplied by the negative-sequence current between the fault phases, working out the real part of a ratio between the voltage of the phase fault point and the voltage drop of an electric transmission line of per unit length, obtaining the additional fault distance caused by a transition resistor, and obtaining the fault distance from the electric transmission line relay location to the phase fault point through the difference between the real part of the ratio between the voltage between fault phases and the voltage drop of the electric transmission line of per unit length and the additional fault distance. The electric transmission line phase fault single-ended distance measuring method solves the problem that the transition resistor influences the precision of electric transmission line phase fault single-ended distance measuring, has high distance measuring precision and is simple in distance measuring principle. In addition, according to the electric transmission line phase fault single-ended distance measuring method, a program is easy to achieve, the fault distance is directly worked out without the need for application of search algorithms, distance measuring is fast, and the instantaneity is strong.

The invention discloses a method for realizing line interphase fault single-ended distance measurement by means of real part characteristics of voltage drop. According to the method, a voltage phase angle at an interphase short fault point is calculated by using fault interphase negative sequence voltage and positive sequence impedance of an electric transmission line per unit length, so that an additional fault distance generated due to transition resistance is calculated, and the fault distance from the electric transmission line protection installation position to the interphase short fault point is obtained by subtracting the additional fault distance generated due to transition resistance from the real part of a ratio of the fault interphase voltage to the voltage drop of the electric transmission line per unit length. The method solves the problem that the transition resistance and load current influence the accuracy of single-ended fault distance measurement; and when a high resistance short fault between phases of the electric transmission line happens, the method has high distance measurement accuracy, the distance measurement principle is simple, the procedure is easy to implement, the fault distance can be directly calculated without a search algorithm, the distance measurement speed is high, and the real-time performance is high.

The invention relates to an anti-collision alarm based on vehicle-mounted internet-of-things. A vehicle-mounted 12V power supply is used for supplying power for the anti-collision alarm in a voltage reducing and stabilizing manner through a vehicle-mounted USB (universal serial bus), an STM32F103 processor module is in interaction with a nanoPAN5275 wireless ranging module through an SPI (serial peripheral interface) so as to acquire wireless distance values which are then displayed through an LCD (liquid crystal display) nixie tube display module. The maximum value displayed on the two-digit nixie tube is 99 meters; if the distance is smaller than a certain threshold value, then the STM32F103 processor module controls a buzzer alarm module to send an alarm, and meanwhile the two-digit nixie tube is in fast blink. The anti-collision alarm based on the vehicle-mounted internet-of-things has the advantages of large ranging, high ranging precision, high ranging speed, capability of measuring multiple wireless distances between the vehicle and multiple adjacent vehicles and the like, and is applicable to sending anti-collision safety alarm for vehicles running in highway at high speed.

The invention discloses a method utilizing lumped parameters to realize line interphase fault single-terminal location. According to the method, the lumped parameters are adopted to describe the physical properties of voltage and current transmission of a transmission line; the fault interphase negative sequence current phase angle of a relay location of the transmission line is adopted to calculate the voltage phase angle of an interphase short circuit fault point; and the fault location is calculated according to the linear relationship between the voltage drop from the relay location of the transmission line to the interphase short circuit fault point and the fault location. According to the invention, as the fault location is calculated according to the linear relationship between the voltage drop from the relay location of the transmission line to the interphase short circuit fault point and the fault location, the influences of the transitional resistance and the load current to the location precision are avoided, the location precision is high, the location principle is simple and the practicability is strong. The method can directly calculate the fault distance without adopting the search algorithm, and is high in location speed and strong in real-time performance.

The invention provides a distance-measuring device which is used for measuring a distance U between a first object and a second object. The distance-measuring device comprises a light-emitting sphere, a prime lens, an image photosensitive element and a processing module, wherein the light-emitting sphere is mounted on the first object; the prime lens is mounted on the second object; the image photosensitive element is arranged in the rear of the prime lens and acquires an image formed by the light-emitting sphere passing through the prime lens; and the processing module is connected with the image photosensitive element and acquires the diameter of the image and calculates the distance U between the first object and the second object according to the following fomula: U=f(D+d) / d, wherein f is the focal distance of the prime lens, and D is the diameter of the light-emitting sphere. The distance-measuring device provided by the invention is simple in structure and high in distance-measuring speed.

The invention relates to a control method for an automatic following car as well as a system. In the control system, infrared receiving tubes which are not uniformly distributed are arranged on an infrared receiving module, and the control method comprises the following steps: receiving an infrared signal of an infrared transmitting module by virtue of the infrared receiving tubes which are not uniformly distributed, gradually aligning a main direction of the infrared receiving module to the infrared transmitting module according to a region orientation of the received infrared signal, and gradually reducing strength of the infrared signal in an alignment process, so as to acquire critical strength that the infrared signal is transmitted to a receiving module. Therefore, the control methodcan synchronously calculate distance between the infrared transmitting module and the receiving module according to the strength of the infrared signal while high-precision rapid direction finding isperformed, and rapid direction finding and range finding as well as rapid automatic following are realized; and by virtue of coordination of a hardwire circuit and a control unit, the control systemcan reduce accuracy requirement on an infrared device, high-precision rapid direction finding and rapid automatic following are realized under the premise of a small amount of infrared receiving modules, and then hardware cost of the control system is reduced.

The invention discloses an additional fault distance impact resistant line single-phase earthing fault single-end ranging method, which comprises the following steps of firstly, measuring fault phase voltage, fault phase negative sequence current, fault phase current and zero sequence current at a protection mounting part of a transmission line to be used as an input quantity; utilizing fault phase electrical quantity to calculate an additional fault distance caused by a transition resistance, and subtracting the additional fault distance caused by the transition resistance from the ratio of fault phase voltage to transmission line voltage drop per unit length to obtain the fault distance between the transmission line protection mounting part and a single-phase earthing fault point. The method provided by the invention overcomes the impact defects of the transition resistance and load current on single-end fault ranging precision, the ranging precision is high when the transmission line has a single-phase high resistance earthing fault, the ranging principle is simple, the program is easily realized, the fault distance is directly calculated without using a search algorithm, the ranging speed is quick, and the real-timeness is strong.

The invention relates to a space ranging method and system for mixed reality equipment. The method includes the following steps that an object to be measured is selected; any point on the object to be measured is selected as a reference point; the distance between the reference point and the mixed reality equipment is measured to obtain the reference distance; a gray level field depth graph of the object to be measured is obtained; the distance between any point on the object to be measured and the mixed reality equipment is obtained according to the reference distance and the gray level field depth graph. The space ranging method and system for mixed reality equipment can fast obtain the distance of any point on the surface of the object to be measured and have the advantages of being high in ranging speed and high in ranging accuracy.

The invention discloses a microwave distance measuring device based on relative sampling, and relates to a microwave distance measuring device. The invention provides a microwave distance measuring device based on relative sampling, which has the advantages of simple structure, high precision and low cost. The device is provided with a frequency control module, a microwave module and a signal processing module, wherein the frequency control module is provided with a main clock signal generator, a main path pulse forming circuit, a sampling clock signal generator and a sampling pulse forming circuit; the microwave module is provided with a local oscillator, a main path switch, a sampling switch, a power amplifier, a low noise amplifier, a filter, a coupler, a transmitting frequency mixer, a receiving frequency mixer and an antenna; and the signal processing module is provided with a transmitting peak value detector, a receiving peak value detector, an OR gate circuit, a microcontrollerand a display. By the sampling signal, of which the period is nearly equal to that of the receiving signal, the relation-based sampling of the transmitting signal and the receiving signal is carried out, so that the expansion of the time difference between the transmitting signal and the receiving signal on the time domain is realized, and the highly precise object distance measurement is achieved.

The invention relates to an underground coal mine multi-branch intersection UWB joint positioning method, and belongs to the field of UWB positioning. The method comprises the following steps: S1, installing a distance measurement card reader at an intersection, and installing a monitoring card reader at a branch; S2, when the identification card enters a positioning area, the central station issuing identification card information to a distance measurement card reader to distribute a distance measurement time sequence; S3, the UWB identification card initiating a TOF distance measurement request to the distance measurement card reader; S3, completing distance measurement; S4, the UWB monitoring card reader of each branch monitoring TOF ranging information and recording monitoring data in the ranging process; S5, the UWB ranging card reader uploading ranging information to the central station through the ring network, and the UWB monitoring card reader uploading monitoring information to the central station through the ring network; S6, the central station calculating the distance between the UWB identification card and the distance measurement card reader and the distance between the UWB identification card and each monitoring card and S7, combining all ranging data, and analyzing the position of the UWB identification card in real time. The method is high in concurrency, high in speed and high in reliability.

The invention relates to a UWB three-radio-frequency ranging circuit and a driving method thereof. The UWB communication technology is adopted, a related ranging algorithm in the field is utilized, and three UWB radio frequency modules and a single radio frequency tag are expanded on a ranging base station for ranging. Each UWB radio frequency module on the three-radio-frequency ranging base station can carry out ranging with a single-radio-frequency UWB tag with the same channel. When the three UWB radio frequency modules on the three radio frequency ranging base station respectively adopt three different channels, one three-radio-frequency UWB ranging base station can simultaneously perform parallel ranging with three UWB tags, so that the ranging speed is increased by nearly three timesby being compared with that of a traditional single-radio-frequency ranging base station; and the position refresh rate is increased by nearly three times under the condition of multi-target positioning. Furthermore, a driving method is established and realized based on the UWB three-radio-frequency ranging circuit; and the main process of the driving method comprises the following steps: creating three tasks with the same priority, and initializing and cyclically scheduling the three tasks to realize parallel UWB signal receiving and transmitting of the three UWB radio-frequency modules.

The invention provides a mobile terminal, comprising a shell; a panel which is set on the shell; a telephone receiver which is set in the shell; and a distance sensor which is set in the shell, wherein the distance sensor is set nearby the telephone receiver, and the distance sensor is used for transmitting and receiving light of a preset frequency, a color of an area on the surface of the panel corresponding to the distance sensor is the same as the color of the panel, and the light of the preset frequency can transmit the color of the panel. According to the mobile terminal provided by the invention, the color of the area on the surface of the panel corresponding to the distance sensor is set to be the same as the color of the panel, so in a process of carrying out silk-screen on the panel, the area on the panel corresponding to the distance sensor does not need to be isolated through utilization of a special fixture, a processing procedure is simplified, and the production efficiency of a product is improved; and moreover, the condition that the panel cannot be used due to skew or tilt of the special fixture in the silk-screen process of the panel is avoided, a rejection rate ofthe panel is reduced, and the production cost of the product is reduced.

The invention discloses a skydiving training lift-off system and relates to the technical field of aviation training instruments. The skydiving training lift-off system comprises a tethered unmanned aerial vehicle end, a ground pay-off device and a distance measuring device. The tethered unmanned aerial vehicle end comprises a tethered unmanned aerial vehicle, a simulated cab is arranged below thetethered unmanned aerial vehicle, and the upper end of the simulated cab is fixedly connected with the tethered unmanned aerial vehicle. The ground pay-off device comprises a bracket, a winding reel,a conductive wire, a motor, a counting device and a controller. The winding reel is arranged on the bracket, the winding reel is rotationally connected with the bracket, the conductive wire is woundaround the winding reel, the conductive wire is connected with the tethered unmanned aerial vehicle end, the motor and the controller are arranged on the side of the bracket, the motor is in transmission connection with the winding reel, the controller is electrically connected with the motor, and the counting device is fixedly connected with the bracket. The distance measuring device is arrangedon the bracket and is connected with the controller. The skydiving training lift-off system can send pilots to high altitude at lower cost and has the beneficial effect of convenient control over thelift-off height.

The invention discloses a circuit interphase fault single-terminal location method capable of preventing additional fault location influence. According to the method, the fault interphase electrical capacity at the relay location of a transmission line is adopted to calculate additional fault location aroused by transitional resistance, and the ratio of the fault interphase voltage and the voltage drop of the transmission line per unit length subtracts the additional fault location aroused by the transitional resistance to obtain the fault location from the relay location of the transmission line to the interphase short circuit fault point. The method provided by the invention solves the problem that the transitional resistance and the load current influence the single-terminal fault location precision, has high location precision and simple location principle, achieves easy program implementation without directly calculating the fault location through the search algorithm, and is high in location speed and strong in real-time performance.

The invention discloses a calibration method of an on-board camera. The calibration method comprises the following steps of equipment installing, calibration site laying and image calibrating. The calibration method of the on-board camera is based on vanishing point detection. During distance measurement, coordinate transformation is conducted on the basis of a vertical coordinate YL of a vanishing point, it is avoided that re-calibration is conducted when the installation height and the pitch angle of a camera change, and operation is simple and convenient. In addition, a data calculation model is simplified, and reaction speed of an on-board computer is increased. The calibration method is unrelated to the pitch angle of an automobile, the corresponding relationship between a space coordinate and an image coordinate is rapidly calculated according to the vertical coordinate YL of the vanishing point on the road surface, distance measurement speed is high, and accuracy is high. The calibration method achieves automatic regulation of calibration data of the camera, and therefore resolves the problem that the measurement accuracy is insufficient when the camera is installed again or the pitch angle changes in a running process of the automobile.

The invention discloses a line single-phase ground fault single-terminal location method capable of preventing influences of both transitional resistance and load current. According to the method, the voltage phase angle of a single-phase ground fault point is calculated by utilizing the fault-phase negative sequence voltage of the relay location of a transmission line and the positive sequence impedance of the transmission line per unit length; the imaginary part of the voltage drop from the relay location of the transmission line to the single-phase ground fault point is calculated according to the characteristic that the voltage along the transmission line is in linear monotone decreasing; and the imaginary part of the voltage drop from the relay location of the transmission line to the single-phase ground fault point is divided by the imaginary part of the voltage drop of the transmission line per unit length to obtain the fault location. The line single-phase ground fault single-terminal location method solves the problem that the transitional resistance and the load current influence the single-terminal fault location precision, is high in single-terminal location precision, simple in location principle and easy in program implementation, and does not need to adopt the search algorithm, so that direct calculation of the fault location is realized, location speed is quick and the real-time performance is strong.

The invention discloses a method of achieving interphase short circuit fault distance measurement of a line by means of single-end electric quantities. The method includes measuring fault interphase voltage, fault interphase currents and fault interphase negative-sequence currents on a protective installation portion of a power transmission line, calculating an imaginary part of a ratio of the fault interphase voltage and the fault interphase negative-sequence currents, calculating an imaginary part of a ratio of voltage drop of the power transmission line per unit length and the fault interphase negative-sequence currents, dividing the imaginary part of the ratio of the voltage drop of the power transmission line per unit length and the fault interphase negative-sequence currents by the imaginary part of the ratio of the fault interphase voltage and the fault interphase negative-sequence currents, and obtaining a fault distance from the protective installation portion of the power transmission line to an interphase short circuit fault point. The method achieves precise measurement of the interphase short circuit fault distance of the power transmission line by means of the single-end electric quantities, and eliminates influences of transition resistance and load currents on measurement precision of the fault distance. Distance measuring principles are simple, programs are easy to achieve, operation amount is little, the distance measuring speed is high, and instantaneity is strong.