Data recording method and system for power transformation and distribution substation

Abstract

The invention relates to the technical field of power systems, and provides a data recording method and system for a power transformation and distribution substation, and the method comprises the steps: carrying out the data collection of the power transformation and distribution substation, enabling the data point collected each time to be n constantly, and numbering the collected data points; when the first data point of the first sampling period appears, n data are continuously stored in the storage array Vcache, the timestamp of the nth data point and the time interval of the data points are recorded, and meanwhile, the sampling period serial number is progressively increased; when the first data point collected in the kth sampling period appears, the collected n data points are judged through a discriminant f (t), and if f (t) of any data point in the sampling period k is equal to 1, n data of the period are stored, the Vcache array is updated, and a timestamp is recorded; if the f (t) of all the data points is equal to 0, only the timestamps are recorded. According to the invention, whether to store and store the content is judged according to the set data precision, the method is simple to implement, the data storage amount can be reduced, and full-cycle data recording can be realized.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and particularly to a data recording and wave - form analyzing method and system for a substation and distribution station. Background Art

[0002] Data recording and waveform analysis is a technical means for real - time acquisition, recording, and storage of data such as electrical quantities and non - electrical quantities during the operation of a power system or other equipment.

[0003] The real - time data sampling of a substation and distribution station can reach the millisecond level. The current waveform recording method is to record the fault data within dozens or hundreds of milliseconds before and after the fault moment when a fault occurs in the equipment. However, in cases such as diagnosing equipment performance and identifying latent faults of equipment, it is necessary to analyze the data of specific states to identify more operating states of the equipment, and the current waveform recording method is difficult to achieve this. Therefore, it is urgent for those skilled in the art to design a data recording and waveform analyzing method applicable to diagnosing and identifying latent faults of equipment. Summary of the Invention

[0004] In order to solve the above problems, the present invention provides a data recording and waveform analyzing method for a substation and distribution station, which uses data compression and storage technologies for continuous data recording and waveform analysis.

[0005] The present invention provides a data recording and waveform analyzing method for a substation and distribution station, including:

[0006] (1) Collect data from the substation and distribution station. The number of data points collected each time is constantly n, and the collected data points are numbered. The data of each cycle starts from the first point and ends at the nth point;

[0007] (2) When the first data point of the first sampling cycle (i.e., k = 1) appears, continuously store n data into the storage array Vcach, record the time stamp of the nth data point and the time interval between data points, and at the same time increment the sampling cycle serial number;

[0008] (3) When the first data point collected in the kth (k>1) sampling cycle appears, the n collected data points are all discriminated by the discriminant formula f(t). If f(t)=1 for any data point in the sampling cycle k, store the n data of this cycle, update the Vcach array and record the time stamp; if f(t)=0 for all data points, only record the time stamp.

[0009] Furthermore, the first data point collected in each cycle is selected as a positive value, and the data point before the first data point is a negative value.

[0010] Furthermore, the calculation formula of the discriminant formula f(t) is:

[0011]

[0012] Among them, V(t) is the data of the t-th point in the new sampling period; Vcach(t) is the stored t-th data, a is the data change accuracy; Vnorm is the reference value of this data, and Vnorm is related to the data type and is set according to the capacity of on-site equipment. For example, for the phase A voltage of one loop of a 10 kV substation of a certain railway, a = 0.005, and Vnorm can be set to 10.5 kV; for the breaker current with a rated capacity of 100 amperes, Vnorm can be set to 100 amperes.

[0013] Furthermore, when the stored data exceeds the preset hard disk capacity, the first-in-first-out (FIFO) strategy is adopted to delete the earliest stored data and time point information to ensure the continuous storage of the latest data.

[0014] The second aspect of the present invention provides a data recording and wave analysis system for a substation, and the data recording and wave analysis system includes:

[0015] Data acquisition module: configured with a dynamic sampling frequency adjustment unit for adjusting the sampling frequency according to the change of the cycle time to ensure that n data points are fixed in each cycle; the first data point collected in each cycle is selected as a positive value, and the data point before the first data point is a negative value.

[0016] Storage management module: includes a storage array Vcach and a circular queue controller to realize the selective storage and capacity management of data;

[0017] Data processing module: integrated with a discriminant calculation unit to detect data changes point by point and trigger the storage operation;

[0018] Time synchronization module: provides a millisecond-level time stamp generation and recording function to ensure the accurate correspondence between data and time.

[0019] The data of the substation is collected by the data acquisition module, and the data collected in the first sampling cycle is sent to the storage management module, and n data are continuously stored in the storage array Vcach, and the time synchronization module is triggered to record the time stamp of the n-th data point and the data point time interval; when collecting the k-th (k>1) sampling cycle, the data is sent to the data processing module, and the discriminant calculation unit in the data processing module discriminates the data points. If f(t)=1 for any data point in the sampling cycle k, the storage management module is triggered to store the n data of this cycle to update the Vcach array, and the time synchronization module is triggered to record the time stamp; if f(t)=0 for all data points, the time synchronization module is triggered to only record the time stamp.

[0020] Furthermore, the storage management module uses a non-volatile memory (such as Flash) and realizes automatic data overwriting through a first-in, first-out (FIFO) strategy, supporting continuous data storage for at least 72 hours.

[0021] Furthermore, the data processing module supports multi-channel parallel processing and can independently perform data recording of multiple circuits (such as A-phase voltage, B-phase current, etc.) in the substation simultaneously.

[0022] Preferably, the data recording system is connected to an external monitoring platform through RS485, Ethernet or a wireless communication interface, supporting remote data query, reference value configuration and storage strategy adjustment.

[0023] The present invention has the following beneficial effects:

[0024] The present invention adjusts the data acquisition frequency according to the data period, fixes the number of data acquisitions in a fixed period, then performs data change calculation, and determines whether to store and the stored content according to the set data accuracy. This method is simple to implement, can reduce the data storage volume, and can achieve full-cycle data recording. Description of the Drawings

[0025] Figure 1 It is the flowchart of data recording in Embodiment 1. Detailed Embodiments

[0026] The technical solutions of the present invention are further described in detail below in conjunction with specific embodiments. However, these embodiments do not limit the present invention. Any similar structures and similar changes using the present invention should be included in the protection scope of the present invention. The commas in the present invention all represent the relationship of "and". The English letters in the present invention are case-sensitive.

[0027] Embodiment 1

[0028] As Figure 1 shown, this embodiment provides a data recording method for a substation, including:

[0029] S1. Perform data acquisition on the substation. The number of data points collected each time is constantly n, and the collected data points are numbered. The data of each cycle starts from the first point and ends at n; the first data point collected in each cycle is selected as a positive value, and the data point before the first data point is a negative value. The data collected by the substation is millisecond-level data; if the time of the cycle changes, the data sampling frequency is adjusted accordingly to ensure that the number of data points is fixed at n;

[0030] S2. When the first data point of the first sampling cycle (i.e., k = 1) appears, continuously store n data into the storage array Vcach, record the timestamp of the nth data point and the time interval between data points, and at the same time increment the sampling cycle serial number;

[0031] S3. When the first data point collected in the k-th (k > 1) sampling period appears, the n data points collected are all discriminated by the discriminant formula f(t). If f(t) = 1 for any data point in the sampling period k, then store the n data of this period, update the Vcach array and record the timestamp; if f(t) = 0 for all data points, then only record the timestamp.

[0032] The calculation formula of the discriminant f(t) is:

[0033]

[0034] where V(t) is the data of the t-th point in the new sampling period; Vcach(t) is the stored t-th data, a is the data change accuracy; Vnorm is the reference value of this data, and Vnorm is related to the data type and is set according to the on-site capacity. For example, for the A-phase voltage of one loop in a 10 kV substation of a certain railway, a = 0.005, and Vnorm can be set to 10.5 kV; for the current of a circuit breaker with a rated capacity of 100 amperes, Vnorm can be set to 100 amperes.

[0035] When the stored data exceeds the preset hard disk capacity, the first-in-first-out (FIFO) strategy is adopted to delete the earliest stored data and timestamp information to ensure the continuous storage of the latest data.

[0036] Embodiment 2

[0037] A data recording and wave analysis system for a substation in this embodiment, the data recording and wave analysis system includes:

[0038] Data acquisition module: Configured with a dynamic sampling frequency adjustment unit, used to adjust the sampling frequency according to the cycle time change to ensure that n data points are fixed in each cycle; and the first data point collected in each cycle is selected as a positive value, and the data point before the first data point is a negative value

[0039] Storage management module: Includes a storage array Vcach and a circular queue controller to realize selective storage and capacity management of data; the storage management module uses a non-volatile memory (such as Flash) and realizes automatic data overwriting through the first-in-first-out (FIFO) strategy, supporting continuous data storage for at least 72 hours.

[0040] Data processing module: Integrated with a discriminant calculation unit to detect data changes point by point and trigger the storage operation; the data processing module supports multi-channel parallel processing and can perform independent data recording and wave analysis on multiple loops (such as A-phase voltage, B-phase current, etc.) in the substation at the same time.

[0041] Time synchronization module: Provides the function of generating and recording millisecond-level timestamps to ensure the accurate correspondence between data and time.

[0042] The data acquisition module collects the data of the substation and sends the data collected in the first sampling period to the storage management module, continuously stores n data into the storage array Vcach, and triggers the time synchronization module to record the timestamp of the nth data point and the data point time interval; when collecting the kth (k>1) sampling period, the data is sent to the data processing module, and the discriminant calculation unit in the data processing module discriminates the data points. If f(t)=1 for any data point in the sampling period k, the storage management module is triggered to store the n data of this period to update the Vcach array, and the time synchronization module is triggered to record the timestamp; if f(t)=0 for all data points, the time synchronization module is triggered to only record the timestamp.

[0043] Preferably, the data recording and wave analysis system is connected to an external monitoring platform through RS485, Ethernet or wireless communication interfaces, and supports remote data query, reference value configuration and storage strategy adjustment.

[0044] The present invention adjusts the data acquisition frequency according to the data period, fixes the number of data acquisitions in a fixed period, then performs data change calculation, and judges whether to store and the stored content according to the set data accuracy. This method is simple to implement, can reduce the data storage volume, and can achieve full-cycle data recording and wave analysis.

[0045] Although the preferred embodiments of the present application have been described, those skilled in the art can make additional changes and modifications once they know the basic creative concept. Therefore, the appended claims are intended to be construed to include the preferred embodiments as well as all changes and modifications falling within the scope of the present application.

Claims

1. A data recording and wave analysis method for a substation and distribution substation, characterized in that Including: (1) Collect data from the substation and distribution station. The number of data points collected each time is constantly n, and the collected data points are numbered; (2) When the first data point of the first sampling period appears, continuously store n data into the storage array Vcach, record the timestamp of the nth data point and the data point time interval, and at the same time increment the sampling period serial number; (3) When the first data point collected in the kth sampling period appears, the n data points collected are all discriminated by the discriminant formula f(t). If f(t)=1 for any data point in the sampling period k, then store the n data of this period, update the Vcach array and record the timestamp; if f(t)=0 for all data points, then only record the timestamp.

2. The data recording and wave - form analysis method for a substation according to claim 1, characterized in that, The first data point collected in each period is selected as a positive value, and the data point before the first data point is a negative value.

3. A data recording and oscillograph method for a substation according to claim 1, characterized in that, The calculation formula of the discriminant f(t) is: Where, V(t) is the data of the tth point in the new sampling period; Vcach(t) is the stored tth data, a is the data change accuracy; Vnorm is the reference value of this data, Vnorm is related to the data type and is set according to the capacity of on-site equipment.

4. A data recording and wave analysis method for a substation and distribution station according to claim 1, characterized in that, When the stored data exceeds the preset hard disk capacity, the first-in, first-out strategy is adopted to delete the earliest stored data and timestamp information to ensure the continuous storage of the latest data.

5. A data recording and wave analysis system for a substation and distribution station, characterized in that, The data recording and wave analysis system is applicable to any one of the data recording and wave analysis methods described in claims 1-4. The data recording and wave analysis system includes: Data acquisition module: configured with a dynamic sampling frequency adjustment unit, used to adjust the sampling frequency according to the change of cycle time to ensure that n data points are fixed collected in each cycle; Storage management module: includes a storage array Vcach and a circular queue controller to realize selective storage and capacity management of data; Data processing module: integrated with a discriminant calculation unit to detect data changes point by point and trigger storage operations; Time synchronization module: provides a millisecond-level timestamp generation and recording function to ensure the accurate correspondence between data and time.

6. A data recording and oscillograph system for a substation and distribution substation according to claim 5, characterized in that, The storage management module uses non-volatile memory and realizes automatic data overwriting through the first-in, first-out strategy.

7. A data recording and oscillograph system for a substation and distribution station according to claim 5, characterized in that, The data processing module supports multi-channel parallel processing and can perform independent data recording and wave analysis on multiple circuits of the substation and distribution station at the same time.

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