65 results about "Conductor sag" patented technology

An apparatus, method, and system for measuring the magnetic field produced by phase conductors in multi-phase power lines. The magnetic field measurements are used to determine the current load on the conductors. The magnetic fields are sensed by coils placed sufficiently proximate the lines to measure the voltage induced in the coils by the field without touching the lines. The x and y components of the magnetic fields are used to calculate the conductor sag, and then the sag data, along with the field strength data, can be used to calculate the current load on the line and the phase of the current. The sag calculations of this invention are independent of line voltage and line current measurements. The system applies a computerized fitter routine to measured and sampled voltages on the coils to accurately determine the values of parameters associated with the overhead phase conductors.

The invention discloses a dynamic capacity increasing monitoring system and method for a power transmission line. The method comprises the steps of carrying out real-time monitoring on the power transmission line, acquiring monitoring data to calculate the safe operation current capacity of the power transmission line, judging whether capacity increasing can be carried out on the power transmission line according to the safe operation current capacity, and if yes, extracting preset capacity increasing information to carry out capacity increasing on the power transmission line; in the process of capacity increasing of the power transmission line, calculating the conductor sag data of the power transmission line according to the monitoring data, and sending the monitoring data and the conductor sag data to an application terminal to display the data. Data acquisition and data monitoring can be carried out on the power transmission line in real time, real-time monitoring is carried out on the conductor sag data of the power transmission line in the process of capacity increasing, the influence on safe operation of the power transmission line from various key factors is comprehensively considered, and therefore the safety is improved.

The invention provides a maximum sag modeling method of a substation flexible conductor on the basis of a catenary. The method includes the steps of firstly, dividing the substation flexible conductor into a strain insulator string and a flexible bus, and determining structure parameters and material parameters; secondly, establishing an X-Y coordinate system with a hanging point of the strain insulator string as an original point, establishing the spatial coordinate equation of the strain insulator string assuming that the hanging point bearing reaction force RA and the horizontal tension T0 are known, and obtaining the horizontal projection length and the perpendicular projection length of the strain insulator string; thirdly, establishing an x-y coordinate system with an end point of the flexible bus as an original point, and obtaining the flexible bus catenary equation on the basis of a catenary theory; fourthly, converting the flexible bus from the x-y coordinate system to the X-Y coordinate system through coordinate conversion, obtaining the substation flexible conductor sag expression through the combination of the spatial coordinate equation of the strain insulator string, and then obtaining the maximum sag value of the flexible conductor. On the basis of the known structure parameters and the known material parameters, the accurate maximum sag value is directly obtained according to any design stress of a substation, the sag control is facilitated, and quite high application value is obtained.

The invention discloses a pole-side conductor sag observation method based on a total station instrument, which is suitable for performing conductor sag observation at the external side of pole span of an electric transmission line with the total station instrument. The total station instrument is disposed at the external side of the pole span to respectively detect the altitude differences of a conductor wire at mount points on a first pole tower and a second pole tower by means of a prism-free function; by means of a planar triangle formed by the observation point and projections of the mount points on the two pole towers, first planar distance and second planar distance are measured; according to geometric principles, projective triangle interior angles and pole span length are calculated and further the position of midpoint of the pole span is determined; the length from the observation point to the midpoint of the pole span is calculated and is multiplied by the tangent value of elevation angle of the total station instrument to calculate the altitude difference of the conductor wire at the midpoint of the pole span; the average value of the first and the second altitude differences minus the altitude difference of the conductor wire at the midpoint of the pole span is finally calculated to obtain the conductor sag. Compared with a conventional conductor sag measurement method, the method allows optional site selection, has high precision and is simple in operations, and can be used in the fields of ultrahigh-voltage transmission line construction, overhead transmission line engineering construction, and measurement and control technologies and instruments and the like.

The invention discloses an electric transmission line conductor sag measuring method based on an angle sensor. The method comprises the steps that (1) the dip angle type angle sensor is installed so that the sag of an electric transmission line conductor can be measured; (2) after a work signal sent by a monitoring center is received by a monitoring extension set, windage yaw dip angle data of the two ends of the electric transmission line conductor are collected through the dip angle type angle sensor installed on an insulator of a site tower and the obtained windage yaw dip angle data are sequentially transmitted to the monitoring extension set and the monitoring center; (3) a sag value f of the electric transmission line conductor is calculated according to expert software embedded in the monitoring center and the windage yaw dip angle data of the electric transmission line conductor; (4) whether the sag value f is in a safe range or not is judged according to the sag value f of the electric transmission line conductor. According to the electric transmission line conductor sag measuring method based on the angle sensor, the size of the sag of the electric transmission line conductor can be rapidly detected and the overhead line accident caused by extremely large or small sag of the conductor is prevented.

The invention discloses a current-carrying limiting value estimation method of an overhead transmission line. The current-carrying limiting value estimation method of the overhead transmission line comprises the steps that (1) a movable camera arranged on the lowest point of an overhead conductor between two towers is used for obtaining the conductor sag; (2) the tensioning force of the conductor is calculated according to the obtained conductor sag; (3) the actual temperature of the conductor is obtained according to the tensioning force of the conductor, the real-time current-carrying amount of the conductor and the environment wind speed; (4) the real-time maximum current-carrying amount of the conductor is estimated according to the actual temperature of the conductor and the obtained environment parameters. According to the current-carrying limiting value estimation method of the overhead transmission line, the actual temperature of the conductor is indirectly obtained by obtaining the conductor sag, the temperature accuracy is far higher than that of a current method that the temperature is directly read by a temperature sensor, and therefore the real-time maximum current-carrying amount of the overhead transmission line can be accurately estimated. The quite important data accuracy of a transmission line dynamic capacity-increasing system serving as an important part of a supporting system of the intelligent transmission line technology in an intelligent power grid is achieved and is greatly significant for safety and efficiency of power transmission and electricity market transactions.

The invention discloses a high voltage transmission conductor sag measuring device. The measuring device comprises a measuring device shell body which is arranged on a transmission conductor. A radar waveguide opening and a radio frequency antenna are arranged on the surface of the measuring device shell body respectively. A monitoring device main control unit is arranged in the measuring device shell body. The monitoring device main control unit comprises a central processing unit which is connected with a radar sensor unit and a power supply unit respectively through wires. The central processing unit is further connected with a data monitoring terminal and a monitoring center respectively through a communication module. The invention further discloses a measuring method of the measuring device, wherein the radar sensor unit is used for transmitting collected sag information to the central processing unit, and then the central processing unit conducts calculation to obtain a transmission conductor sag value. The high voltage transmission conductor sag measuring device and method can monitor the changes in the sag of a high voltage transmission line in real time and transmit the monitoring data to the backstage monitoring center, thereby guaranteeing the safe operation of an electric power circuit.

The invention discloses a high-precision overhead transmission conductor sag detection method, and relates to the technical field of metering length, width or thickness by metering equipment characterized by adopting an optical method. The method comprises the following steps: acquiring conductor point cloud data of different instantaneous points of one overhead transmission conductor in a measurement period; performing data processing on the wire point cloud data, establishing a wire coordinate system, and extracting wire feature point data; establishing a catenary equation of the overhead transmission conductor and a sag equation of the overhead transmission conductor based on the conductor coordinate system; and fitting and solving a catenary equation of the overhead transmission line and a sag equation of the overhead transmission line by adopting a nonlinear least square method based on the line feature point data. The method is high in precision, and can calculate the conductor sag at any position.

The invention provides a conductor slag on-line monitoring system comprising a signal collecting device, a monitoring host computer, a power supply device, an information transmitting device and a monitoring center, wherein the signal collecting device is used for collecting the temperature as well as the inclination angle and the current of a conductor; the monitoring host computer is used for pretreating the collected information to acquire the distance between the lowest point of a conductor slag and the ground and packing the distance between the lowest point of the conductor slag and the ground and the collected information; the power supply device is used for supplying power, transforming voltage and starting or stopping the monitoring host computer; the information transmitting device is used for transforming the packed information to the monitoring center; and the monitoring center is used for presetting warning values, establishing an early warning mechanism, configuring the packed information to different local area networks, and forecasting the variation trend of the conductor slag and the transmission capacity of a transmission line in real time. The conductor slag on-line monitoring system has the characteristics of strong real-time performance, high safety, reliable forecasting and the like and can be widely applied to electric systems.

The invention relates to a power transmission line sag measurement method based on ultrasonic distance measuring and a system thereof. The system comprises an ultrasonic range finder fixed on a power transmission line. An ultrasonic emission head in the ultrasonic range finder points to a downward direction. A ground where the pointing of the emission head is arranged to be a level base surface. The ultrasonic range finder emits an ultrasonic wave to the level base surface and collects and receives the ultrasonic wave reflected by the level base surface. A collected signal is calculated and processed and correlation information is fed back to a monitoring terminal. The monitoring terminal receives the information and then carries out further processing, and outputs alarm information. The ultrasonic range finder is fixed to the power transmission line. An ultrasonic transmitting terminal in the ultrasonic range finder vertically points to a downward direction. An underface ground is provided with the level base surface so as to ensure that an ultrasonic echo can be received. Detection reliability is increased. Through using an ultrasonic distance measuring method to measure a power transmission conductor sag, the price of the ultrasonic range finder is low so that large-scale use can be achieved.

The invention discloses a power transmission line crossings processing apparatus and system. The apparatus comprises an information module used for obtaining information of a route and a tower, an input information module used for receiving input information which includes at least one of power transmission crossings information, tree line distance point-to-point measurement, conductor sag and grounding line information, and an analysis calculation module connected with the input information module and used for analyzing the input information to obtain prompt information whether a power transmission line has a fault or not. According to the apparatus and the system, the technical problem of no mutual support of working site support and supervision, pre-warning and pre-control before an event and production decision-making due to lack of a power transmission line crossings management platform is solved.

The invention discloses a conductor sag measurement method. The conductor sag measurement method includes: respectively marking two ends of a conductor as A1 and B1, wherein projections of the A<1> and the B<1> on projections of horizontal planes of O<1> and O<2> are respectively A<0> and B<0>, and remarking the lowest point inside the A<1> and the B<1> is C<1>, wherein the projection of the C<1> on the projections of the horizontal planes of the O<1> and the O<2> is C<0>; measuring distance L between the O<1> and the O<2> and calculating the distance h<2> according to the similar triangle principle; prolonging A<1> and A<0> to D point to enable the B<1>, the C<0> and the D to be on the same plane; acquiring the distance from the A<1> and B<1> to the C<0> is h<0> according to the similar triangle principle, wherein h<0> and h<2> are a conductor sag. With the method, problems about visual errors of a direct sag board measurement method and failure to measurement due to vision limit can be effectively solved, and the problem that block space among towers needs to be known with the theodolite measurement method.

The invention discloses an automatic sag detection and tension stringing system for an overhead transmission line. The automatic sag detection and tension stringing system comprises: a wireless remotecontrol trolley that is arranged on a conductor to be tested, wherein the wireless remote control trolley is provided with a satellite receiving device used for receiving position information sent bya satellite positioning system, and the wireless remote control trolley is provided with a wireless communication system; a tension stringing actuator for taking up and paying off the conductor; a control station located on the ground, wherein the control station emits a movement instruction and transmits the movement instruction to the wireless remote control trolley through the wireless communication system to control the wireless remote control trolley to move to a test position, the wireless remote control trolley obtains the position information and transmits the position information tothe control station, the control station processes the position information at the position to be tested to calculate the sag value, compares the calculated sag value with a target sag in the controlstation and sends a tension stringing command to control the tension stringing actuator for taking up and paying off the conductor. The automatic sag detection and tension stringing system achieve thereal-time automatic online detection and automatic tension stringing of the conductor sag, and can be used for more refined re-detection of the conductor which is subjected to tension stringing at aconstruction site.

The invention discloses a computing method for torsional rigidity of a split conductor of an overhead power transmission line. The method comprises the following steps of: firstly, analyzing length change of a sub-conductor due to a torsional movement of the split conductor, and deducing a practical level tension computational formula according to a linear formula of the power transmission line and material property of the conductor when the sub-conductor is torsional; then carrying out a mechanical analysis for a four-split conductor under the action of a torque, in the analysis process, utilizing a characteristic that the split conductor is divided into multiple subspans through a conductor spacer, firstly carrying out a force analysis for the subspans, and finally obtaining a torque balance equation under the action of the torque, and further obtaining a computational formula for the torsional rigidity of the four-split conductor. Finally, summarizing a common computational formula for the torsional rigidity of the split conductor for any split number. In the computing method, the method is adopted to calculate the torsional rigidity of the split conductors with parameters, such as different split numbers and span length and the like, and higher computational accuracy can be achieved, and effectiveness and adaptability of the computing method can be proved.

The invention discloses a method for designing ADSS optical cables controlled by conductor sag. The method is characterized by including the following steps: 1) calculating conductor sag under maximum operation condition of different spans according to original line conditions; 2) employing the conductor sag as an ADSS optical cable sag controlling condition to unify optical cable model selection standards; 3) determining mount points of the ADSS optical cables according to electric-field intensity of lines; 4) conducting stringing design by using selected optical cables. As the ADSS optical cables need smaller safety distance than conductors and optical cable sag is not more than the conductor sag, the method for designing ADSS optical cables controlled by the conductor sag needs no cross bridging check, solves the problem of standardization of the ADSS optical cables, forms a scientific and precise design method, improves the safety of the ADSS optical cables and reduces design workload.

The invention relates to a dynamic prediction method for power transmission line ground wire crossing electrical safety distance. The temperature of a power transmission line conductor and the temperature of a crossed overhead ground wire are changed along with the change of an environment temperature and the continuous change of a conductor load, thereby causing the rise or fall of sag of the conductor and the crossed overhead ground wire. Due to different sag change amplitudes, the electrical safety distance of the ground wire is shortened. According to the scheme, the change degree of the conductor sag and the overhead ground wire sag under any temperature condition is judged according to a calculation method of a conductor sag catenary basic model and an overhead ground wire sag basicmodel, and the electrical safety distance of the conductor and the overhead ground wire is measured and calculated through the difference value of sag changes of the conductor and the overhead groundwire. According to the dynamic prediction method, whether the electrical safety distance between the wire and the overhead ground wire meets the requirement in a future period of time can be predicted.

The invention discloses a power transmission line current-carrying capacity boundary dynamic evaluation method. The method comprises the following steps: (1) inputting sensor information and environmental meteorological information collected by a power transmission line into a power transmission line digital twinning model; (2) calculating a current-carrying capacity boundary; (3) calculating a steady-state value and a temperature rise value of the wire temperature after current transition; (4) judging whether the steady-state value of the conductor temperature exceeds a preset temperature value or not to determine whether the current-carrying capacity boundary needs to be reduced or not to recalculate the steady-state value of the conductor temperature, and outputting the reduced current-carrying capacity boundary as a reference; (5) calculating the maximum conductor sag corresponding to the maximum current-carrying capacity of the power transmission line; (6) judging whether the maximum conductor sag corresponding to the maximum current-carrying capacity of the power transmission line meets the requirement of the power transmission line for the safe distance to the ground; and (7) obtaining the final current-carrying capacity boundary of the power transmission line. On the premise of ensuring stable operation of the system and equipment safety, the credibility and accuracy oftransmission capacity evaluation of the power transmission line are improved.

The invention provides a conductor sag monitoring device based on laser distance measurement. The monitoring device comprises a laser distance measurement sensor hung on a conductor. The laser distance measurement sensor is used for measuring the distance between the conductor and the ground. The monitoring device can further comprise an angle sensor, the angle between a laser pulse and a perpendicular line perpendicular to the ground is measured through the angle sensor, and the perpendicular distance between the conductor and the ground is calculated. The invention further provides two methods for using the conductor sag monitoring device based on the laser distance measurement. The distance between the conductor and the ground and the conductor sag are measured with the laser distance measurement methods, the measurement accuracy is high, the implement methods are simple, and the collected data are accurate and reliable.

The invention discloses an online monitoring system for a high-tension transmission line based on a wireless sensor network. The online monitoring system comprises a conductor temperature monitoring terminal, a meteorological environment monitoring terminal, a circuit data collection terminal, a conductor sag monitoring terminal, the wireless sensor network, a circuit monitoring base station, a database terminal, a background monitoring center station and an alarm terminal module, wherein the circuit data collection terminal is used for collecting data information of the conductor temperature monitoring terminal, the meteorological environment monitoring terminal and the conductor sag monitoring terminal, transmitting the data information to the circuit monitoring base station through the wireless sensor network based on a Zigbee protocol, and transmitting the data information to the background monitoring center station through a GPRS (general packet radio service) network; the background monitoring center station is used for storing the received circuit information into the database terminal, and timely sending out alarm information through the alarm terminal module when the data information is abnormal. According to the online monitoring system, real-time omnibearing monitoring of related parameters such as conductor temperature, conductor sag and meteorological environment can be achieved; and the online monitoring system can be widely applied to monitoring of the high-tension transmission line of an electric power system.

The invention relates to methods for maintaining double-circuit lines, in particular to a method for replacing a single-circuit wire of common-tower double-circuit lines. A tension field and a traction field are arranged according to landforms, error climbing prevention safety measures are arranged on a tower, and corresponding safety measures are distributed in the traction field. The end portion of a new wire is connected with the end portion of an old wire through a snakeskin sleeve, and wing clamps are used in old wire strain section connection. The mode that the old wire and the new wire are in transition is adopted in the wire replacement process, that is, the wire is dragged through a tractor, tension stringing is adopted in the whole process, the traction field is used as a wire hanging end, the tension field is used as a wire tightening end for reversely dragging and tightening a conductor sag and hanging the wire, and iron tower accessories and corresponding hardware fittings are mounted after the wire is hung. The problem that the double-circuit lines need to be in the power failure simultaneously in the previous work of replacing the common-tower double-circuit wire is solved, and power supply reliability is greatly improved. An error climbing prevention isolating device is arranged on the common-tower double-circuit iron tower, and the method can be applied to the operation of replacing the wire and can be popularized to other common-tower double-circuit work.

A typical air bridge is an aluminum conductor suspended across an air-filled cavity to connect two components of an integrated circuit, two transistors for example. The air-filled cavity has a low dielectric constant which reduces cross-talk between neighboring conductors and improves speed and efficiency of the integrated circuit. However, current air bridges must be kept short because typical aluminum conductors sag too much. Accordingly, one embodiment of the invention forms air-bridge conductors from an aluminum-beryllium alloy, which enhances stiffness and ultimately provides a 40-percent improvement in air-bridge lengths.

The invention provides a method for dynamically predicting an electrical safety distance between a power transmission line wire and a tree. A clearance distance between a conductor sag point and a tree in a prediction state is calculated and is compared with a minimum electrical safety distance between a conductor and the tree specified in transmission line design specifications, and safety of a transmission line is monitored. Through the method, the unmanned aerial vehicle power transmission line channel inspection technology is perfected, and the problem that power transmission line channelmanagement is out of control in the unmanned aerial vehicle inspection period is solved; and meanwhile, the defect of conventional prediction of the dynamic safety distance between the wire and the tree is overcome, the prediction accuracy is improved by introducing an arc suspension chain model based on the temperature of the wire and the linkage effect of the seasonal growth change trend of thetree, and the operation safety and reliability of a power transmission line are enhanced.

The invention discloses a system and a method for measuring conductor sag based on an inclination angle difference method. The system comprises a measuring device A1, a measuring device A2 and a host module, wherein the measuring device A1 comprises a single-axis inclination angle sensor I, an MCU processor I, a data storage device I and a wireless transceiver I; the measuring device A2 comprises a single-axis inclination angle sensor II, an MCU processor II, a data storage device II and a wireless transceiver II; and the host module comprises a wireless transceiver III and a host. According to the system and the method provided by the invention for measuring the conductor sag based on the inclination angle difference method, a sensor non-linear error caused by the temperature is made up by mutual compensation of data measured by the two devices, and a more accurate sag value can be acquired.

The invention discloses a GPU (graphic processing unit) parallel technology based conductor sag calculation method. The method includes steps: step A) acquiring basic parameters in calculation, wherein the basic parameters include meteorological region parameters and conductor parameters; step B) grouping poles and towers into each strain section according to business rules of the power field, respectively calculating pole and tower parameters and span parameters of each strain section according to the basic parameters to obtain the pole and tower parameters and the span parameters of each strain section; step C) adopting a GPU for parallelly calculating conductor stress and conductor sag according to the obtained pole and tower parameters and the span parameters of each strain section. By the principles, parallel processing of mass sag data can be realized, processing speed is greatly increased, data processing accuracy is greatly improved, and the GPU parallel technology based conductor sag calculation method is pretty applicable to rural power distribution networks.