82 results about "Transmission line parameters" patented technology

The invention provides a power system transmission line parameter synchronic measurement and recording device. An IEC61850 model is uniformly established on a server end according to IEC61850 standard and a fault wave-recording logic model and a transmission line parameter measurement logic module with the same hardware platform are set on the server end and the system configuration is realized according to IEC61850-6 and an independent used configuration tool is formed. The fault wave-recording and transmission line parameter measurements respectively model different logic devices according to IEC61850 standard, namely the data record is realized when the power system is in failure and the synchro measurement of the power system transmission line parameters is realized, thereby solving the problem that the data, parameter read by manpower out-of-step for many times are not accurate in power failure. The accuracy of the line parameter is increased. The power system transmission line parameter synchronic measurement and recording device can be widely used for various application fields such as line wave recording, main-change wave recording, set wave recording, and transmission line parameter synchro measurement.

A system and method for estimating parameters of transmission lines employing phasor measurement units is provided, wherein measurements are provided from the phasor measurement units relating to a transmission line. These measurements are filtered to remove invalid measurements. Using the remaining valid measurements, resistance, reactance and grounding admittance are calculated and estimated and checked for errors.

The invention discloses a method for identifying transmission line parameters. The method comprises the following steps: firstly, establishing a linear equation set for describing a transmission line model according to an equivalent model of a transmission line; dividing multiple sets of sampling data of a PMU (Phasor Measuring Unit) within a period of time into multiple data windows in fixed length; specific to the sampling data of each data window, utilizing a least square method to identify the parameters according to the established linear equation set, thereby obtaining an identifying result under each data window; arraying the identifying results under all the data windows in an ascending sort according to the magnitude sequence of the identifying results, thereby obtaining a row of sequencing statistics; and taking a median of the obtained sequencing statistics as a final parameter identifying result. According to the method, the identified parameters are closer to real parameters of the line and are more credible, and the error resistance is ultrahigh.

The invention relates to an online identification system of a transmission line parameter and an identification method thereof. The technical characteristics are that the online identification system includes a data receiving module, a steady state data processing module and a parameter identification module which are connected in sequence; the data receiving module is for receiving PMU measured data issued by a provincial WAMS system front-end processor in real time, and screening out transmission line telemetry data to be identified; the steady state data processing module is for steady state processing of the transmission line telemetry data output by the data receiving module to remove telemetry bad data and transient state data and generate steady data of a 5-minute section; and the parameter identification module is for accurately identifying and calculating a transmission line parameter using the PMU measured data after steady state processing, taking a result obtained by accurate identification and calculation as a final transmission line steady state identification parameter, and verifying the precision of the transmission line online identification parameter. According to the invention, the parameter of the transmission line operation can be accurately identified, and the identification precision and practicability are high.

Embodiments relate to enhancing echo cancellation in a transceiver integrated circuit (IC) for full-duplex communication by providing a signal path connected to a dummy driver that replicates a signal path between a main driver and a counterpart transceiver IC to cause a duplicated signal generated by the dummy driver to more closely replicate a sending signal generated by the main driver. The signal path connected to the dummy driver includes circuit elements having transmission line parameters and RLC parameters that replicate transmission line parameters and RLC parameters of circuit elements in the signal path between the main driver and the counterpart transceiver IC.

The invention discloses a power grid fault diagnosis and transmission line parameter identification system which comprises a fault characteristic analysis module, a fault intelligent diagnosis module,a power grid fault deduction module, a line parameter identification module, a protection information management main station FIS application and a visual man-machine interface. The input ends of thefault characteristic analysis module, the fault intelligent diagnosis module, the power grid fault deduction module and the line parameter identification module are connected with the protection information management main station FIS application, and the output ends of the fault characteristic analysis module, the fault intelligent diagnosis module, the power grid fault deduction module and theline parameter identification module are connected with the visual man-machine interface. According to the power grid fault diagnosis and transmission line parameter identification system, auxiliary tools and convenient means for power grid professional management and operation personnel to fast locate power grid fault problems and transmission line parameter checking are provided.

The invention belongs to the electromagnetic compatibility transmission line unit length electrical parameter analysis field, and more specifically relates to a heterogeneous multiple conductor transmission line inductance matrix direct evaluation method. The method comprise: first employing fine line grids to disperse each signal line conductor and a grounding plate into fine line structures, wherein the current fine line of each signal line conductor forms a loop with the sth fine line of the grounding plate to obtain Nc loops; meanwhile calculating a directional factor referring to transmission line parameter analysis; writing equations in a matrix form; and obtaining a heterogeneous multiple conductor transmission line impedance matrix. The method can obtain accurate measurement results, have a more convenient calculation process than a traditional method, directly solve an inductance matrix without multitime conversion, and possess high practical reference value.

There is described a method of determining power transmission line parameters using non-synchronous measurements acquired from different locations along a power transmission line. The method comprises (a) acquiring first measurement data comprising corresponding pairs of voltage and current measurement values measured at a first location along the power transmission line at predetermined points in time relative to a first time reference, (b) acquiring second measurement data comprising corresponding pairs of voltage and current measurement values measured at a second location along the power transmission line at predetermined points in time relative to a second time reference, (c) calculating initial values of the power transmission line parameters and an initial value of the difference between the first time reference and the second time reference based on the first measurement data and the second measurement data, and (d) calculating resulting values of the power transmission line parameters and a resulting value of the difference between the first time reference and the second time reference by utilizing a least squares algorithm and the initial values of the power transmission line parameters, the initial value of the difference between the first time reference and the second time reference, the first measurement data, and the second measurement data. Furthermore, a data acquisition device and a system for determining power transmission line parameters as well as a computer program and a data carrier are described.

The invention discloses a stranded wire RLCG parameter extraction method based on a BAS-BP algorithm. According to the stranded wire RLCG parameter extraction method, a novel stranded wire RLCG parameter extraction network model is established based on a beetle antennae search algorithm (BAS) and a BP neural network algorithm. The stranded wire RLCG parameter extraction method can utilize the network to extract a high-precision RLCG electromagnetic parameter matrix at any position of a stranded wire, and comprises the following steps of: firstly, establishing a stranded wire model and extracting a parameter sample by virtue of an ANSYSQ3D software platform; carrying out sample processing after a space structure of the stranded wire is analyzed; importing the processed data into a BAS-BP neural network model; and finally, acquiring an optimal extraction network through training and testing. The existing transmission line RLCG parameter extraction methods are mostly based on a numericalalgorithm, lack of processing capacity for stranded wire type non-uniform transmission lines, is based on the intelligent algorithms, has the advantages of high precision, high efficiency and the likecompared with a traditional method, has no special requirements for wire types, and can better solve the problem of extraction of stranded wire electromagnetic parameters.

A method for calculating efficiency of a power supply system includes: displaying a parameter selection interface on the display unit for selecting power supply parameters and transmission line parameters. Obtaining power supply parameters and transmission line parameters selected by the user via the parameter selection interface when determining the user has finished the selection. Determining a efficiency of a selected power supply of the power supply parameters according to the relationship table, and calculating a sum efficiency according to the obtained power supply parameters and the transmission line parameters and the efficiency of the selected power supply. And calculating a total efficiency of the power supply system according to each sum efficiency when determining that all of the power supplies of the power supply system have been selected.

The invention discloses an online calibration method and device for a synchronous phasor measurement unit. The online calibration method comprises the steps of measuring the synchronous phasor measurement unit under different load conditions to acquire multiple groups of synchronous phasor measurement unit data, and calculating multiple groups of transmission line parameters according to the multiple groups of synchronous phasor measurement unit data; solving a partial derivative of each measurement value according to the multiple groups of synchronous phasor measurement unit data, and generating an impedance partial derivative parameter; acquiring static parameters of a transmission line from an energy management system so as to determine a search space, performing clustering on partial derivatives of the line parameters in the search space, and generating a parameter error together with the multiple groups of transmission line parameters; determining a system error according to the impedance partial derivative parameter and the parameter error, and performing calibration on the synchronous phasor measurement unit according to the system error. According to the invention, an enough accurate parameter error can be generated according to an energy management system mathematical model and the static parameters, and the model based calibration method is enabled to have practical application values.

The invention relates to a high robustness electric transmission line parameter estimating method based on a multi-time period PMU, which belongs to the power system scheduling automation field. In this method, a parameter estimating model constituted of an objective function and constraint conditions is established; the objective function is the smallest among residual error weighted sum squares in N time periods; based on the KKT complementary slack condition corresponding to the parameter estimating model, the parameter estimating model is solved to acquire an optimum solution X; the time periods are arranged in descending order according to the maximum residual error of each of the time period; the time period of the optimum residual error is recorded as k; if the maximum residual error in the time period is smaller than a measuring residual error threshold, the parameter estimation is finished; and the acquired optimum solution is used as the estimation result of the parameter. According to the invention, the analytical form of the optimum solution of the model is solved based on the KKT condition, thus the calculating efficiency is ensured to be high; through the exclusion of the damaged datum and the iterative process of the parameter estimation, the damaged datum are eliminated effectively, thus improving the accuracy of the parameter estimation and ensuring the practicality of the method.

The invention discloses a method for estimating the parameters of an incompletely commutated three-phase power transmission line based on PMU measurement, including the estimation of 12 admittance parameters and the estimation of 12 impedance parameters. The beneficial effects are as follows: the method for estimating the parameters of an incompletely commutated three-phase power transmission linebased on PMU measurement overcomes the shortcomings of the previous parameter estimation methods; the estimation errors of self-impedance and self-admittance parameters are less than 1%, and the estimation errors of mutual-impedance and mutual-admittance parameters are less than 2%; and more accurate power transmission line parameters can be provided for an energy management system, so that the error parameters of an incompletely commutated three-phase power transmission line can be identified accurately and calibrated in time and online.

The invention discloses an improved Monte Carlo method for solving a section DC load flow model, and the method comprises the following steps: 1), establishing the section DC load flow model; 2), generating random variables in the sections of a corresponding load, generator active output and transmission line parameters through employing a stochastic simulation technique, wherein the random variables are called as scenes; 3), adding an extreme scene on the basis of the scenes generated at step 2), wherein the extreme scene indicates the upper and lower boundaries of the parameter section; 4),carrying out the statistical operation of the maximum and minimum values of the load flow variables in all scenes; 5) outputting a result which comprises a section calculation result of a phase angleand transmission power. The method provided by the invention employs the stochastic simulation technique for generating a series of scenes in the section of input data, and obtains the load flow section through the statistical operation of the maximum and minimum values of the load flow variables in the generated scenes. Moreover, the method further improves the precision of a section DC load flowmodel solution through the consideration to the extreme scene of the input data.

The invention relates to a parameter determination method of a power distribution device, the power distribution device and a device. The method comprises the steps of obtaining the working frequencyof a power distribution device and the power division ratio range of the output end of the power distribution device; determining reference power frequency information according to the working frequency and the power division ratio range, wherein the reference power frequency information is used for indicating the linear relation between the power division ratio of the output end of the power distribution device and the working frequency; calling a simulation model corresponding to the power distribution device; adjusting the transmission line parameters of the simulation model, and obtainingthe real-time power frequency information outputted by the simulation model; and when the real-time power frequency information is matched with the reference power frequency information, outputting atransmission line parameter corresponding to the real-time power frequency information. The power distribution device composed of transmission lines produced on the basis of the obtained transmissionline parameters effectively improves the beam forming of the broadband antenna.