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CN-122001092-A - Electrical equipment operation monitoring system based on intelligent control

CN122001092ACN 122001092 ACN122001092 ACN 122001092ACN-122001092-A

Abstract

The invention relates to the technical field of power distribution monitoring and discloses an intelligent control-based electric equipment operation monitoring system which comprises a grid structure identification unit, a short circuit capacity assessment unit, a transient characteristic extraction unit, a monitoring fixed value follow-up setting unit, an operation abnormality judgment unit and an operation abnormality judgment unit, wherein the grid structure identification unit is used for collecting switch contact signals and establishing a real-time power grid topology model, the short circuit capacity assessment unit is used for reconstructing a node admittance matrix by using the real-time power grid topology model and calculating node equivalent short circuit impedance, the transient characteristic extraction unit is used for sampling node transient current signals and extracting a high-frequency transient component sequence, the monitoring fixed value follow-up setting unit is used for establishing a mapping relation between the node equivalent short circuit impedance and the short circuit capacity, the monitoring threshold is corrected in a follow-up mode, the operation abnormality judgment unit is used for calculating transient integral energy of the high-frequency transient component sequence, and generating operation abnormality signals when the transient integral energy deviates from the monitoring threshold.

Inventors

  • WU QIUYAN
  • Zhuang Peicheng

Assignees

  • 泉州市鑫科自动化设备有限公司

Dates

Publication Date
20260508
Application Date
20260410

Claims (9)

  1. 1. An intelligent control-based electrical equipment operation monitoring system, comprising: The grid structure identification unit is used for acquiring physical auxiliary contact switching signals of each circuit breaker and each isolating switch in the power distribution network, and updating a real-time power grid topology model reflecting the physical communication state of the primary side energy transmission path in real time by analyzing the physical auxiliary contact switching signals; the short-circuit capacity evaluation unit is used for reconstructing a node admittance matrix according to the real-time power grid topological model, and calculating a node equivalent impedance value of the target node seen to the system side so as to represent the power supply rigidity of the target node; The transient characteristic extraction unit is used for acquiring a transient current signal at a target node, extracting a high-frequency transient component sequence reflecting the degradation state of the internal insulation initial stage of the electrical equipment by utilizing a multi-scale differential transformation algorithm, wherein the high-frequency transient component sequence comprises transient energy attributes reflecting waveform distortion characteristics; the monitoring fixed value follow-up setting unit is used for establishing a mapping relation between the node equivalent impedance value and the monitoring fixed value, and correcting the monitoring fixed value in a follow-up mode according to the mapping relation so as to establish a target monitoring boundary; And the operation abnormality judging unit is used for calculating the integral energy value of the transient component sequence in the characteristic frequency band, comparing the integral energy value with the target monitoring boundary and outputting an operation abnormality signal of the electrical equipment of the target node.
  2. 2. The intelligent control-based electrical equipment operation monitoring system according to claim 1, wherein the monitoring constant value follow-up setting unit reversely corrects the threshold value of the monitoring constant value according to the change trend of the node equivalent impedance value, wherein the threshold value of the monitoring constant value is reduced when the node equivalent impedance value is increased to represent that the target node is in a weak electrical connection state, and the threshold value of the monitoring constant value is increased to inhibit protection misoperation caused by background noise disturbance when the node equivalent impedance value is reduced to represent that the target node is in a strong electrical connection state.
  3. 3. The intelligent control-based electrical equipment operation monitoring system according to claim 1, further comprising a power flow tracing unit, wherein the power flow tracing unit is used for acquiring voltage phase difference polarities between a target node and an adjacent node when the operation abnormality judging unit outputs an operation abnormality signal, establishing a power flow direction by combining a real-time power grid topology model, analyzing a propagation vector of a transient component sequence on a physical grid path, and positioning a disturbance source node.
  4. 4. The intelligent control-based electrical equipment operation monitoring system according to claim 1, further comprising a closed loop control unit, wherein the closed loop control unit is configured to send a compensation command to the active power control module at the target node when the abnormal operation signal indicates that the transient component sequence is distorted and does not reach the physical isolation threshold, and inject a cancellation current with a phase opposite to that of the transient component sequence, so as to suppress the initial degradation signal.
  5. 5. The intelligent control-based electrical equipment operation monitoring system according to claim 4, wherein the monitoring constant follow-up setting unit takes the standardized impedance coefficient as a correction factor of the target monitoring boundary, so that the target monitoring boundary is in nonlinear convergence along with the increase of the standardized impedance coefficient, and the transient overvoltage risk caused by the decrease of the power supply rigidity of the target node is offset.
  6. 6. The intelligent control-based electrical equipment operation monitoring system according to claim 1, wherein the transient characteristic extraction unit comprises a high-frequency sampling module, the high-frequency sampling module acquires a current differential signal of a target node at a sampling frequency not lower than 200kHz, and the steps of performing discrete fourier transform on the current differential signal to establish a frequency domain distribution characteristic are completed, and extracting spectral components in a frequency band range from 5kHz to 50kHz to generate a transient component sequence, in step S71.
  7. 7. The intelligent control-based electrical equipment operation monitoring system according to claim 1, further comprising a life prediction unit, wherein the life prediction unit is used for accumulating the frequency and duration of the transient component sequence deviating from the target monitoring boundary, constructing an equipment operation trend model, and calculating the residual insulation life of the electrical equipment to which the target node belongs according to the evolution slope of the trend model.
  8. 8. The intelligent control-based electrical equipment operation monitoring system according to claim 1, further comprising a central scheduling module, wherein the central scheduling module is used for calculating a power balance allowance of a non-fault area according to a real-time power grid topology model after a disturbance source node is positioned, commanding actions of solid state circuit breakers of branches to which the disturbance source node belongs, and completing flow balance scheduling on the non-fault area.
  9. 9. The intelligent control-based electrical equipment operation monitoring system according to claim 1, wherein the grid structure identification unit comprises an edge control terminal arranged on the side of the distribution transformer, the edge control terminal monitors auxiliary contact state information of a circuit breaker in the distribution network in real time, and when a contact state jump is monitored, the short circuit capacity evaluation unit is triggered to complete admittance matrix reconstruction.

Description

Electrical equipment operation monitoring system based on intelligent control Technical Field The invention belongs to the technical field of power distribution monitoring, and particularly relates to an intelligent control-based electrical equipment operation monitoring system. Background The current power distribution monitoring system generally adopts a monitoring mode of comparing an extracted power frequency steady-state electrical characteristic parameter with a preset static threshold value, the mode is established on an ideal assumption that the equivalent short-circuit capacity of a power distribution network node is constant, the operation state of electrical equipment is judged by monitoring a voltage or current effective value acquired in real time, in a conventional power distribution environment with relatively fixed physical topology, the mode can meet basic safety protection requirements to realize identification and removal of conventional faults such as overload or short-circuit, however, in a large industrial park power grid which bears continuous production tasks and faces the dynamic reconfiguration requirements of power distribution nodes, the dynamic drift of the electrical rigidity of the nodes cannot be perceived by the system due to frequent switching of the physical topology of the system, when the nodes are in a high-impedance state of weak electrical connection, serious voltage drop or overvoltage fluctuation can be generated due to tiny transient distortion, the main network absorbs fluctuation with the same amplitude in a low-impedance state of strong electrical connection, and the traditional setting logic is caused to peel off the bottom constraint between the electrical characteristics of the nodes and the physical topology of the whole network, so that the dynamic drift of the electrical rigidity of the nodes cannot be perceived by the system, and the system faces the sensitivity of unmatched or the large risk of mismatching in the operation during switching of the operation mode. Although the industry tries to optimize the recognition precision by means of improving the sampling frequency or applying a statistical prediction model and the like, the mode usually only establishes a correlation on a data layer, does not touch the physical essence of short-circuit capacity drop caused by the topology change of a power distribution network, is difficult to provide a control response with physical certainty under an unstable power grid stiffness environment, a software control strategy and an adaptive setting method are difficult to provide hysteresis for complex working conditions, for example, china patent publication No. CN117791479A discloses an overcurrent protection adaptive setting method and device. Therefore, how to combine the real-time physical topology evolution of the power distribution network, calculate the equivalent impedance of the node Thevenin and construct a follow-up protection boundary according to the equivalent impedance, and realize the accurate monitoring of the operation state of the electrical equipment, thus the invention is the technical problem to be solved. Disclosure of Invention The invention provides an intelligent control-based electrical equipment operation monitoring system, which comprises: The grid structure identification unit is used for acquiring physical auxiliary contact switching signals of each circuit breaker and each isolating switch in the power distribution network, and updating a real-time power grid topology model reflecting the physical communication state of the primary side energy transmission path in real time by analyzing the physical auxiliary contact switching signals; the short-circuit capacity evaluation unit is used for reconstructing a node admittance matrix according to the real-time power grid topological model, and calculating a node equivalent impedance value of the target node seen to the system side so as to represent the power supply rigidity of the target node; The transient characteristic extraction unit is used for acquiring a transient current signal at a target node, extracting a high-frequency transient component sequence reflecting the degradation state of the internal insulation initial stage of the electrical equipment by utilizing a multi-scale differential transformation algorithm, wherein the high-frequency transient component sequence comprises transient energy attributes reflecting waveform distortion characteristics; the monitoring fixed value follow-up setting unit is used for establishing a mapping relation between the node equivalent impedance value and the monitoring fixed value, and correcting the monitoring fixed value in a follow-up mode according to the mapping relation so as to establish a target monitoring boundary; And the operation abnormality judging unit is used for calculating the integral energy value of the transient component sequence in the characteristic frequency band, co