CN-121973656-A - Grid-connected operation and control inspection system for electric automobile charging pile

CN121973656ACN 121973656 ACN121973656 ACN 121973656ACN-121973656-A

Abstract

The invention belongs to the technical field of electric vehicle charging facilities, and aims to solve the problems that different causes cannot be accurately stripped in the same power transition phenomenon in the prior art, and early warning of the health state of a control system is realized based on transient characteristics in the transition process; according to the invention, the internal command signal of the controller is introduced as a causal anchor point, the power change event is decoupled into two event types with different physical essence, namely the main control transition and the external disturbance transition, the fundamental problem that different causes behind the same power transition phenomenon cannot be distinguished in the prior art is solved, and the early warning of the dynamic performance degradation of the controller is realized by constructing a preset standard path feature library and diagnosing the main control transition event by adopting a probability matching method.

Inventors

WANG JUNSHU
ZHANG QIN
WANG JUNHU

Assignees

北京京鑫清洁能源有限公司

Dates

Publication Date: 20260505
Application Date: 20260313

Claims (10)

1. Electric automobile fills electric pile and is incorporated into power networks operation and control inspection system, its characterized in that includes: the state transition monitoring module is used for acquiring power related data and controller internal instruction data in the running process of the charging pile, detecting a state transition event according to the power related data and extracting power change path characteristics corresponding to the state transition event; The time sequence association analysis module is used for determining a first time sequence association characteristic of the state transition event according to the time sequence association relation between the power related data and the instruction data in the controller; The transition event classification module classifies the state transition event into a main control transition event representing state transition caused by active control or an external disturbance transition event representing state transition caused by external disturbance according to the matching result of the first time sequence association characteristic and a preset classification rule; the main control diagnosis module is used for determining a first diagnosis conclusion according to the main control transition event and combining the first matching degree of the power change path characteristics with a preset standard path characteristic library and a preset matching degree threshold value; the external disturbance diagnosis module is used for determining a second diagnosis conclusion according to the second matching degree of the power change path characteristics and a disturbance type characteristic library constructed based on the historical external disturbance transition events for the external disturbance transition events; and the dynamic optimization module is used for dynamically adjusting the preset matching degree threshold according to the statistical characteristics of the diagnosis conclusion of the external disturbance transition event.
2. The system for grid-connected operation and control inspection of electric automobile charging pile according to claim 1, wherein the power related data comprises an active power time sequence, the controller internal instruction data comprises a given value time sequence of a power loop or a current loop, and the specific acquisition process of the power related data and the controller internal instruction data in the operation process of the charging pile comprises: synchronously collecting an active power instantaneous value and an internal command instantaneous value of a controller at a frequency not lower than a preset sampling rate to obtain a first power sequence and a first command sequence after alignment; And respectively carrying out low-pass filtering processing on the first power sequence and the first instruction sequence to obtain a second power sequence and a second instruction sequence.
3. The system for grid-connected operation and control inspection of electric automobile charging pile according to claim 2, wherein the process of detecting the state transition event and the process of extracting the power change path feature corresponding to the state transition event specifically comprise: Calculating a power change rate sequence according to the second power sequence; Determining the starting moment of a state transition event when the absolute values of a plurality of continuous sampling points in the power change rate sequence exceed a preset change rate threshold value, and determining the ending moment of the state transition event when the absolute values of the sampling points in the power change rate sequence fall back below the preset change rate threshold value and the power fluctuation in the subsequent preset duration is smaller than a preset fluctuation threshold value; And intercepting a corresponding second power sequence segment according to the starting time and the ending time of the state transition event, and calculating at least one of the following characteristics as the power change path characteristic, namely overshoot, rise time, second derivative zero crossing times and normalized path signature vectors, wherein the normalized path signature vectors are obtained by carrying out sectional aggregation approximation on the normalized power sequence segment.
4. The electric vehicle charging pile grid-tie operation and control verification system according to claim 2, wherein the determining of the first time-sequence-related characteristic of the state transition event comprises: Calculating a power change rate sequence in a first preset window before and after the starting moment of a state transition event according to the second power sequence, and recording the power change rate sequence as a first change rate sequence; calculating an instruction change rate sequence in the first preset window according to the second instruction sequence, and marking the instruction change rate sequence as a second change rate sequence; Calculating normalized cross-correlation functions of the first change rate sequence and the second change rate sequence under different relative delays; And determining the peak value of the normalized cross-correlation function and the corresponding delay time thereof as a first time sequence association characteristic of the state transition event.
5. The electric vehicle charging pile grid-connected operation and control inspection system according to claim 1, wherein the specific process of classifying the state transition event as a master transition event or an external disturbance transition event comprises: when the peak value in the first time sequence association characteristic is larger than a preset first correlation coefficient threshold value and the corresponding delay time is in a preset synchronous range, classifying the state transition event as a main control transition event; classifying the state transition event as a nuisance transition event when the peak value in the first time sequence association characteristic is smaller than a preset second correlation number threshold value or the corresponding delay time exceeds a preset delay threshold value; And when the state transition event neither meets the classification condition of the main control transition event nor the classification condition of the external disturbance transition event, marking the state transition event as a pending transition event, and prolonging an observation window or calling a standby classification rule to reclassify.
6. The electric vehicle charging pile grid-tie operation and control verification system of claim 1, wherein for a master transition event, the determining of the first diagnostic conclusion comprises: determining a corresponding target transition type according to the initial power and the target power of the main control transition event; Invoking a preset standard path feature library corresponding to the target transition type, wherein the preset standard path feature library comprises a probability distribution model constructed based on a history main control transition event; Calculating a first matching degree of the power change path characteristics of the main control transition event under the probability distribution model, wherein the first matching degree is represented by adopting a log-likelihood value; and when the first matching degree is smaller than a current preset matching degree threshold value, judging that the main control transition event is a main control path abnormal event, and otherwise, judging that the main control path abnormal event is normal.
7. The electric vehicle charging pile grid-tie operation and control verification system according to claim 1, wherein the determining of the second diagnostic conclusion for the external disturbance transition event comprises: Performing similarity calculation on the power change path characteristics of the external disturbance transition event and the baseline characteristics of each disturbance type cluster in a disturbance type characteristic library, wherein the disturbance type characteristic library is obtained by performing online clustering on historical samples of the external disturbance transition event, and each disturbance type cluster comprises a mean vector and a covariance matrix as baseline characteristics; When a disturbance type cluster with similarity meeting a preset clustering condition and minimum mahalanobis distance exists, classifying the external disturbance transition event into the cluster, and updating a mean vector and a covariance matrix of the cluster in a moving average mode, wherein the weight factor of historical data is larger than that of a current sample; Calculating the mahalanobis distance between the power change path characteristic of the external disturbance transition event and the baseline characteristic of the cluster where the power change path characteristic is located as a second matching degree; When the second matching degree exceeds a preset abnormal threshold value, judging that the external disturbance transition event is a disturbance response abnormal event, otherwise, judging that the external disturbance transition event is normal disturbance; and when no disturbance type cluster with similarity meeting a preset clustering condition exists, marking the external disturbance transition event as an unknown disturbance event.
8. The system for grid-connected operation and control verification of electric vehicle charging pile according to claim 1, wherein the dynamic adjustment process of the preset matching degree threshold comprises counting the number of disturbance transition events determined as disturbance response abnormal events within a preset time period Total number of nuisance transition events The disturbance health index is calculated according to the following formula : Wherein epsilon is a preset constant, and according to the disturbance health index And presetting a modulation factor alpha, and presetting a basic value of a matching degree threshold according to the following formula Dynamically correcting to obtain the current preset matching degree threshold value : The current preset matching degree threshold value is set A first match comparison for a subsequent master transition event.
9. The electric vehicle charging pile grid-tie operation and control verification system of claim 8, further comprising a periodicity evaluation module: acquiring first matching degrees corresponding to a plurality of main control transition events in a preset history period, and forming a first matching degree sequence according to time sequence; Obtaining disturbance health indexes corresponding to a plurality of external disturbance transition events in the preset historical period, and forming a disturbance health index sequence according to time sequence; And calculating a correlation coefficient between the first matching degree sequence and the disturbance health index sequence as a first correlation index, and outputting a comment conclusion through the first correlation index.
10. The electric vehicle charging pile grid-connected operation and control inspection system according to claim 9, wherein the outputting process of the comment conclusion comprises: outputting an evaluation conclusion of the dynamic performance attenuation of the system when the first association index is larger than a preset first association threshold value and the first matching degree sequence and the disturbance health index sequence are in a synchronous descending trend; Outputting an evaluation conclusion of the dual-mode abnormal mode transfer when the first association index is smaller than a preset second association threshold and the first association index is negative; and outputting an evaluation conclusion of the dual-mode decoupling normal when the absolute value of the first association index is smaller than or equal to a preset third association threshold.

Description

Grid-connected operation and control inspection system for electric automobile charging pile Technical Field The invention belongs to the technical field of electric vehicle charging facilities, and particularly relates to an electric vehicle charging pile grid-connected operation and control inspection system. Background At present, the inspection of the grid-connected running state of the charging pile mainly depends on a monitoring and threshold alarming mechanism of a steady state electric index, specifically, the output power of the charging pile is acquired in real time in the prior art and compared with a preset target power, when the deviation continuously exceeds a certain range and is maintained for a certain time, the control failure or the equipment abnormality is judged, and the inspection mode can effectively identify an obvious power exceeding standard event under a steady running working condition. However, the actual operation scene is far more complex than the ideal working condition, the power state of the charging pile is not always stable at a certain fixed value, but the power state of the charging pile is frequently changed due to two different causes, namely active control, namely that the charging pile actively changes output power according to a preset control strategy in response to a power grid dispatching instruction or user regulation operation, and external disturbance, namely that the vehicle-mounted load (such as an air conditioner, seat heating and the like) of the electric automobile is randomly switched, so that the direct-current side load of the charging pile is suddenly changed, and further the passive change of the output power is caused, and the two causes can lead the charging pile to be transited from one power state to the other state, but the existing monitoring technology only focuses on the change of the power value and can not distinguish different causes behind the same power transition phenomenon. If the normal external disturbance is misjudged as abnormal control of the charging pile, unnecessary operation and maintenance intervention can be caused, otherwise, if the transient response abnormality (such as overshoot increase and oscillation aggravation) caused by the performance degradation of the controller is misattributed as the external disturbance, the early warning time can be missed until the fault is found when the steady-state power exceeds the standard to cause the protection action, the deeper problem is that the health degradation of the charging pile control system is always reflected on the dynamic response characteristic in the state transition process instead of the final steady-state value, and the existing steady-state threshold-based inspection logic cannot sense the transient process, so that the potential fault of equipment is difficult to identify in the sprouting stage. Therefore, how to accurately strip different causes in the same power transition phenomenon and realize early warning of the health state of the control system based on transient characteristics in the transition process becomes a technical problem to be solved. Disclosure of Invention The invention aims to provide a grid-connected operation and control inspection system of an electric automobile charging pile, which is used for solving the problems that different causes cannot be accurately stripped in the same power transition phenomenon in the prior art, and early warning of the health state of a control system is realized based on transient characteristics in the transition process; the invention aims to solve the technical problem of providing an electric automobile charging pile grid-connected operation and control inspection system which can accurately strip different causes in the same power transition phenomenon and realize early warning of the health state of a control system based on transient characteristics in the transition process. The aim of the invention can be achieved by the following technical scheme: Electric automobile fills electric pile and is incorporated into power networks operation and control inspection system includes: The state transition monitoring module is used for acquiring power related data and controller internal instruction data in the running process of the charging pile, detecting a state transition event according to the power related data, and extracting power change path characteristics corresponding to the state transition event; the time sequence association analysis module is used for determining a first time sequence association characteristic of the state transition event according to the time sequence association relation between the power related data and the instruction data in the controller; The transition event classification module classifies the state transition event into a main control transition event representing state transition caused by active control or an external disturbance transition event representin