13 results about "Mutual impedance" patented technology

The invention relates to the technical field of transformer detection, in particular to a transformer comprehensive state monitoring method and a transformer monitoring system.The transformer comprehensive state monitoring method comprises the steps that a broadband detection impedance matrix data set is obtained through detection and calculation from multiple ports of a transformer, and then the detection impedance matrix data set is obtained through a neural network and a particle swarm optimization algorithm; obtaining an evaluation parameter vector and an evaluation impedance matrix of each frequency point; correcting the health reference conditions by using each parameter in the evaluation parameter vector, and judging the fault type of the transformer; respectively judging the winding deformation degree and the transformer health degree by utilizing the symmetry of the evaluation impedance matrix and the difference degree between the evaluation impedance matrix and the health reference matrix; the difference between the mutual impedance corresponding to the evaluation impedance matrix and the health reference matrix is calculated, and when the difference is large, an impedance path between two ports corresponding to the mutual impedance is marked as a fault position; the problems that real-time monitoring cannot be achieved through a common transformer detection method, and a detection result is not clear are solved.

The invention discloses a new energy system transient overvoltage evaluation method based on a multi-station effective short circuit ratio, and the method comprises the steps: calculating a mutual impedance threshold value of a to-be-analyzed new energy station according to a voltage variation threshold value of the to-be-analyzed new energy station in a low-voltage ride-through control strategy; determining all new energy station sets entering low-voltage ride through due to the short-circuit fault of the new energy station to be analyzed based on a mutual impedance threshold value among multiple stations; calculating a multi-station effective short-circuit ratio of the new energy station to be analyzed according to the new energy station set; calculating the transient process maximum voltage of the to-be-analyzed new energy station based on the reactive current coefficient of the to-be-analyzed new energy station in the low voltage ride through control strategy and the multi-station effective short circuit ratio; according to the transient process maximum voltage and a preset overvoltage threshold value, whether the new energy station to be analyzed has transient overvoltage or not is judged.

The invention relates to the technical field of rail transit lightning stroke protection and electrical safety analysis, and discloses a method for establishing an equivalent calculation model of a steel rail transmission line, a terminal and a medium. The method is applied to lightning stroke transient analysis of a non-standard I-shaped structural steel rail, and comprises the following steps: firstly, arranging two cylindrical surface current layers outside a steel rail conductor; respectively calculating an impedance parameter of a system formed by the inner cylindrical surface current layer and the steel rail, an impedance parameter of a system formed by the outer cylindrical surface current layer and the ground, and a mutual impedance parameter of the steel rail; analyzing the influence of the skin effect and the magnetic saturation effect on the steel rail impedance parameter by adopting finite element software, and obtaining a steel rail frequency domain impedance parameter matrix finally used for modeling according to an analysis result; and finally, based on the steel rail frequency domain impedance parameter matrix, establishing a time domain transmission line equation containing frequency-dependent parameters. The method can obtain the impedance frequency domain characteristic parameters of the section conductor of the steel rail, analyzes the influence rule of magnetic saturation nonlinearity on the impedance parameters in the steel rail, and establishes a steel rail lightning stroke transient response calculation model.

The application discloses a kind of monitoring method and system of electric power grounding system, applied to resistance detection technical field, method includes: obtaining the position distribution information of each ground body in target electric power grounding system;Based on position distribution information, the mutual impedance information of each ground body is obtained;Determine the target excitation frequency point of ground body;The target excitation signal is applied to corresponding ground body, and corresponding response signal is obtained;Orthogonal demodulation is carried out to the target impedance component extracted from response signal, and resistance response component and reactance response component are obtained;According to resistance response component, the equivalent resistance value of ground body is obtained, and the impedance data of ground body is determined based on reactance response component to process equivalent resistance value;Based on the impedance data of ground body, the resistance monitoring data of target electric power grounding system is obtained.The monitoring method and system of electric power grounding system provided by the application effectively improve the accuracy of resistance monitoring of the electric power grounding system of multiple ground body.

This invention relates to the field of power supply testing and automated detection technology, specifically to a multi-channel parallel electrical parameter testing system for power adapters. The system includes a parallel test loop, a multi-channel signal acquisition module, a state assessment and quantization module, an intelligent scheduling decision module, and a dynamic decoupling execution module. It acquires real-time electrical parameter signals from each test channel and extracts them to form a multi-dimensional electrical state sequence. A cross-impedance matrix between channels is constructed. Based on a matrix perturbation model, nonlinear coupling analysis is performed to generate electrical crosstalk entropy and predict the system failure risk value. Then, based on a comparison of the electrical crosstalk entropy with a preset safety threshold, a target scheduling strategy is determined, and the parallel test loop and test load are reconstructed and adjusted in timing. This invention achieves stable operation in a high-density parallel testing environment.

The invention discloses a low-voltage distribution network power supply line electric leakage fault positioning method and device and a storage medium, and relates to the technical field of power grid power supply safety. The positioning method comprises the following steps: acquiring historical electrical quantity data of a target station area in a normal operation state, further calculating equivalent mutual impedance among user nodes, and determining an anomaly judgment threshold value; acquiring actually measured electrical quantity data of the target station area when the electric leakage fault occurs, and further calculating current equivalent mutual impedance among the user nodes; comparing the current equivalent mutual impedance with a corresponding anomaly determination threshold to identify an abnormal mutual impedance; for each user node, counting the number of identified abnormal mutual impedance in the current equivalent mutual impedance between the user node and all other user nodes; and determining the user node with the maximum number of abnormal mutual impedance as a priority troubleshooting object of the electric leakage fault. According to the method, the problem of large calculation error of a virtual impedance method depending on strong hypothesis is solved, and the troubleshooting efficiency is improved.

The invention belongs to the technical field of multi-core mobile cable electrical parameter calculation, and discloses a general solving method for multi-core mobile cable electrical parameters based on field-circuit collaborative analysis. The method comprises the following steps: firstly, acquiring structural parameters and material electrical parameters of the multi-core mobile cable, injecting a multi-frequency harmonic signal into the cable, collecting first and tail end voltage and current time domain signals, and extracting each frequency phasor through Fourier transform; simplifying an impedance and admittance matrix based on a cable structure and conductor layout, and solving mutual admittance between a conductor core and a shielding layer by using a measurement phasor; further calculating other mutual admittance and mutual impedance based on an electromagnetic field analytical method; and finally, substituting all mutual parameters into a phasor equation, and solving the self-impedance and the residual mutual impedance of each conductor. According to the method, through field-circuit collaborative analysis, the efficiency of an analytical method and the precision of a numerical method are considered, the complete electrical parameters of the multi-core mobile cable under the broadband can be rapidly and accurately obtained, and the method is suitable for system simulation, protection setting and fault analysis of power transmission and communication cables and has good engineering applicability and calculation efficiency.

The invention relates to the technical field of transformer detection, in particular to an impedance matrix data generation method and an impedance detection system.The impedance detection system executes the method to generate impedance matrix data, and the method comprises the steps that whether the transformer is online or not is judged through a voltage transformer and a current transformer; if the on-line voltage signal and the on-line current signal of each port are directly collected on line, calculating the on-line impedance vector and all on-line mutual impedances of the port according to the specific frequency point of the operation of the transformer, and splicing an on-line impedance matrix; otherwise, broadband off-line detection is carried out, and an off-line impedance matrix is spliced; secondly, eliminating external influences of the two impedance matrixes, and marking effective impedance matrix data and invalid impedance matrix data; the problem of monitoring and fault diagnosis omission caused by impedance matrix data frequency point limitation and the problem of monitoring and fault diagnosis result error caused by external influence are solved.

The application relates to the technical field of rail transit lightning protection and electrical safety analysis, and discloses a method for establishing an equivalent calculation model of a steel rail transmission line, a terminal and a medium. The method is applied to lightning transient analysis of a non-standard I-shaped structure steel rail. First, two layers of cylindrical current layers are arranged outside a steel rail conductor; then, impedance parameters of a system composed of the inner cylindrical current layer and the steel rail, impedance parameters of a system composed of the outer cylindrical current layer and the ground and mutual impedance parameters of the steel rail are calculated; the influence of skin effect and magnetic saturation effect on the impedance parameters of the steel rail is analyzed by using finite element software, and a final steel rail frequency domain impedance parameter matrix used for modeling is obtained according to the analysis result; and finally, a time domain transmission line equation containing frequency variable parameters is established based on the steel rail frequency domain impedance parameter matrix. The application can obtain the frequency domain characteristic parameters of the conductor impedance of a steel rail section, analyze the influence law of magnetic saturation nonlinearity on the internal impedance parameters of the steel rail, and establish a lightning transient response calculation model of the steel rail.

The invention provides a new energy multi-machine transient synchronous stability collaborative optimization control method and system, and belongs to the field of new energy power generation. The system comprises a plurality of new energy power generation units, a grid-connected converter, a common coupling point and a cooperative control center. The method comprises the steps of collecting common point voltage and current of each converter; calculating mutual impedance voltage influence between the converters; evaluating the transient synchronous stability margin of each power generation unit based on mutual impedance influence; by taking improvement of the overall stability margin of the system as a target, performing collaborative optimization to generate a current instruction of each converter; and converter output is controlled according to the instruction. Through system-level cooperative control, mutual impedance negative interaction during multi-machine parallel connection is quantified and inhibited in real time, the synchronization stability of the new energy multi-machine system under the transient fault of the power grid is effectively improved, and chain instability is prevented.

The application relates to a power distribution network shunt active power filter configuration optimization method and device, computer equipment, a storage medium and a computer program product. The method comprises the following steps: obtaining each harmonic impedance of each branch of a power distribution network, each harmonic mutual impedance between nodes, an association matrix formed between all nodes and all branches, and each harmonic current of each branch when no shunt active power filter is configured; determining a target function of the shunt active power filter configuration of the power distribution network, and taking the target function as a harmonic network loss suppression model, wherein the target function comprises a harmonic network loss function of the power distribution network and a configuration quantity function of the shunt active power filter; and solving the harmonic network loss suppression model in a preset solution range through a multi-objective particle swarm optimization algorithm to obtain a global platonic optimal solution set of the harmonic network loss suppression model. The method can improve the use value and efficiency of the shunt active power filter.

The application discloses a low-voltage distribution network power supply line electric leakage fault positioning method and device and a storage medium, and relates to the technical field of power grid power supply safety. The positioning method comprises the following steps: acquiring historical electrical quantity data of a target station area in a normal operation state, and then calculating equivalent mutual impedances between user nodes and determining an abnormal judgment threshold; acquiring measured electrical quantity data of the target station area when an electric leakage fault occurs, and then calculating current equivalent mutual impedances between the user nodes; comparing the current equivalent mutual impedances with corresponding abnormal judgment thresholds to identify abnormal mutual impedances; for each user node, counting the number of the current equivalent mutual impedances between the user node and all other user nodes that are identified as abnormal mutual impedances; and determining the user node with the largest number of abnormal mutual impedances as a priority investigation object of the electric leakage fault. The application solves the problem of large calculation error of the virtual impedance method depending on strong assumptions, and improves the fault investigation efficiency.

The application relates to an equivalent uplink and downlink current ratio fault location method combined with segmented reactance tables, which uses the uplink and downlink current ratio method combined with segmented reactance tables to replace the reactance ratio method and the common uplink and downlink current ratio method commonly used in the current double-line direct supply operation mode for fault location, divides the double-line direct supply traction network into several sections according to the different unit impedances, and then calculates the reactance value of each section according to the impedance and mutual impedance of each section. The method can not only consider the influence of the lightning protection coil and the power supply line on the location result, but also can guarantee the location accuracy when the number of stations is large, so that the location error is controlled within 250 meters; the method can ensure that the maintenance personnel quickly find the fault point, timely treat the fault, and restore the normal operation of the line, and is very important for the safety, reliability and efficient transportation of the railway system.