Externally-hung data acquisition and transmission equipment applied to intelligent electric meter

Abstract

The invention relates to a plug-in data acquisition and transmission device applied to an intelligent electric meter. The plug-in data acquisition and transmission device comprises a user side acquisition terminal, a transformer side acquisition terminal and a gateway. The two acquisition terminals are respectively connected with the corresponding intelligent electric meters through RS-485, read electric energy data according to an acquisition period and write the electric energy data into a local data slot in a covering manner; and the gateway issues an uploading instruction to the two ends according to the uploading period, and the terminal uploads the latest value of the data slot and then empties the data slot. And the gateway aligns and packs the user side data and the transformer side data uploaded in the same round in the time dimension, and uploads the data to the master station for line loss and operation analysis. According to the scheme, the meter does not need to be replaced, high-frequency acquisition and accurate alignment are realized, and the transformation and communication cost is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electric power information collection and communication, and particularly relates to an external data collection and transmission device applied to a smart meter. BACKGROUND

[0002] With the wide application of smart grids and power distribution automation systems, power companies have higher requirements for real-time monitoring of power distribution area operation states, line loss analysis and user power consumption behavior analysis.

[0003] Existing electric energy collection systems mainly rely on a smart meter and concentrator / collection device architecture, and upload data through RS-485, carrier wave or public network communication modes. However, the traditional architecture still has the following technical problems: Most existing smart meters have a sampling period of 15 minutes to 1 hour, and the data timeliness is insufficient, so it is difficult to realize second-level or minute-level electric energy change tracking and dynamic line loss analysis. If high-frequency collection function is to be realized, the smart meter usually needs to be replaced or the concentrator device needs to be upgraded, which involves on-site power outage construction, is high in cost, long in period and has the risk of affecting the accuracy of metering. Moreover, due to the asynchronous collection of transformer side and user side, the data cannot be accurately time-aligned, resulting in errors in calculating line loss and affecting the accuracy of evaluating the operation of the area. SUMMARY

[0004] To at least partially overcome the problems that electric energy data is difficult to realize high-frequency collection and data cannot be accurately time-aligned in the related art, the present application provides an external data collection and transmission device applied to a smart meter.

[0005] The scheme of the present application is as follows: An external data collection and transmission device applied to a smart meter, comprising: a user side collection terminal, a transformer side collection terminal and a gateway; The user side collection terminal is connected to the smart meter at the user side through an RS-485 interface, and the transformer side collection terminal is connected to the smart meter at the transformer side through an RS-485 interface. The user side collection terminal collects user side electric energy data based on a collection period, and stores the collected user side electric energy data into a user side data slot; the transformer side collection terminal collects transformer side electric energy data based on a collection period, and stores the collected transformer side electric energy data into a transformer side data slot; When receiving an upload instruction sent by the gateway, the user side collection terminal uploads the latest value in the user side data slot to the gateway and empties the user side data slot; when receiving an upload instruction sent by the gateway, the transformer side collection terminal uploads the latest value in the transformer side data slot to the gateway and empties the transformer side data slot. The gateway sends upload commands to the user-side acquisition terminal and the transformer-side acquisition terminal based on the upload cycle; after receiving the power data uploaded by the user-side acquisition terminal and the transformer-side acquisition terminal, it aligns the two types of power data in the time dimension and packages them, and sends the packaged data to the main station system.

[0006] Preferably, the user-side data acquisition terminal acquires user-side power data through a first communication protocol; The transformer-side data acquisition terminal acquires electrical energy data from the transformer side through a first communication protocol; The user-side data acquisition terminal and the transformer-side data acquisition terminal upload data to the gateway through the second communication protocol.

[0007] Preferably, the first communication protocol is the DLT 645 protocol; The second communication protocol is a gateway communication protocol.

[0008] Preferably, it further includes: First communication module and second communication module; The first communication module and the second communication module are connected to communication networks in different directions.

[0009] Preferably, the first communication module is a 230MHz power grid communication module that connects to the southbound communication network; The second communication module is a 4G CAT1 communication module, which is connected to the northbound communication network.

[0010] Preferably, the user-side power data and the transformer user-side power data include: Three-phase / single-phase voltage, current, active power, reactive power, and cumulative electrical energy.

[0011] Preferably, an upload cycle includes multiple acquisition cycles.

[0012] Preferably, the acquisition period is 5 seconds; The upload cycle is 1 minute.

[0013] Preferably, the gateway reads the transformation ratio coefficient from the topology configuration table and performs transformation ratio correction on the power data based on the transformation ratio coefficient.

[0014] Preferably, the gateway aligns the two types of electrical energy data in the time dimension, adds the meter address, and then packages them.

[0015] The technical solution provided in this application may include the following beneficial effects: This technical solution uses a three-stage architecture consisting of an external user-side data acquisition terminal, a transformer-side data acquisition terminal, and a gateway. It directly reads data from existing smart meters via RS-485 without the need to replace meters or concentrators or perform on-site power outages. The data acquisition cycle can be configured to the second / minute level, significantly improving data timeliness and reducing transformation costs and risks.

[0016] The gateway issues upload commands simultaneously according to the upload cycle. Both terminals only upload the "latest value" in their respective data slots. The same round of uploads is used as the time anchor point to complete the alignment, avoiding alignment errors caused by the inconsistency of the internal clocks of the meters, and ensuring the data consistency between the transformer side and the user side at the same time plane.

[0017] The equal measurements of electrical energy / power obtained at the same time anchor point on both sides are used for line loss and energy balance calculations, which can significantly reduce systematic errors caused by asynchronous acquisition and support dynamic line loss analysis and rapid assessment of transformer area operation status at the minute or even second level.

[0018] The acquisition cycle and upload cycle are independently configurable, which can ensure the capture of transients on the terminal side and flexibly control the upload rhythm according to the analysis needs of the main station, realizing a flexible strategy of "high-frequency acquisition and cost-saving upload".

[0019] Each terminal uses an overlay-type "data slot" to retain and send only the latest value, and clears it after uploading. This avoids duplicate and redundant historical data back transmission, reduces link bandwidth and main station storage / computing pressure, and improves the overall link throughput and stability.

[0020] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0021] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0022] Figure 1 This is a schematic diagram of the structure of an external data acquisition and transmission device for use in a smart meter, provided in one embodiment of this application; Figure 2 This is a schematic diagram of the structure of an external data acquisition and transmission device for use in a smart meter, provided in another embodiment of this application.

[0023] Reference numerals: User-side acquisition terminal-1; Transformer-side acquisition terminal-2; Gateway-3; First communication module-4; Second communication module-5. Detailed Implementation

[0024] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0025] Figure 1 This is a schematic diagram of an external data acquisition and transmission device for smart meters provided in one embodiment of this application, with reference to... Figure 1 An external data acquisition and transmission device for use in smart meters, comprising: User-side data acquisition terminal 1, transformer-side data acquisition terminal 2, and gateway 3; User-side data acquisition terminal 1 is connected to the smart meter on the user side via an RS-485 interface; transformer-side data acquisition terminal 2 is connected to the smart meter on the transformer side via an RS-485 interface. User-side data acquisition terminal 1 collects user-side power data based on the acquisition cycle and stores the collected user-side power data in the user-side data slot; transformer-side data acquisition terminal 2 collects transformer-side power data based on the acquisition cycle and stores the collected transformer-side power data in the transformer-side data slot. When user-side data acquisition terminal 1 receives an upload command from gateway 3, it uploads the latest value in the user-side data slot to gateway 3 and clears the user-side data slot; when transformer-side data acquisition terminal 2 receives an upload command from gateway 3, it uploads the latest value in the transformer-side data slot to gateway 3 and clears the transformer-side data slot. Gateway 3 sends upload commands to user-side acquisition terminal 1 and transformer-side acquisition terminal 2 based on the upload cycle; after receiving the power data uploaded by user-side acquisition terminal 1 and transformer-side acquisition terminal 2, it aligns the two types of power data in the time dimension and packages them, and sends the packaged data to the main station system.

[0026] It should be noted that the user-side data acquisition terminal 1 obtains the user-side power data through the first communication protocol; The transformer-side data acquisition terminal 2 acquires electrical energy data from the transformer side through the first communication protocol; User-side data acquisition terminal 1 and transformer-side data acquisition terminal 2 upload data to gateway 3 via the second communication protocol.

[0027] The first communication protocol is used for communication between the acquisition terminal and the smart meter. The terminal reads the target register data from the meter through the first communication protocol according to the configured acquisition period, and overwrites it into the local data slot, retaining only the latest value.

[0028] The second communication protocol is used for data interaction between the acquisition terminal and gateway 3. Gateway 3 sends upload commands to the acquisition terminal according to the upload cycle. After receiving the upload command, the acquisition terminal sends the latest value in the data slot, along with the associated time tag / upload round identifier, quality flag, device identifier, etc., to gateway 3 according to the second communication protocol, and clears the data slot after successful upload. The second communication protocol includes handshake confirmation and error retransmission mechanisms to cope with link jitter and short-term interruptions.

[0029] Preferably, the first communication protocol is the DLT 645 protocol; The second communication protocol is the Gateway 3 communication protocol.

[0030] To ensure full compatibility with existing smart meters, this embodiment limits the communication protocol between the data acquisition terminal and the meter side to the DLT645 protocol; the communication between the terminal and the gateway 3 side adopts a customized gateway 3 communication protocol, and the two are independent of each other at the physical layer, link layer and application layer.

[0031] Figure 2 This is a schematic diagram of the structure of an external data acquisition and transmission device for smart meters provided in another embodiment of this application, referring to... Figure 2 External data acquisition and transmission equipment used in smart meters also includes: First communication module 4 and second communication module 5; The first communication module 4 and the second communication module 5 are connected to communication networks in different directions.

[0032] Preferably, the first communication module 4 is a 230MHz power grid private network communication module, which is connected to the southbound communication network; The second communication module 5 is a 4G CAT1 communication module, which connects to the northbound communication network.

[0033] "First communication module 4 and second communication module 5" refer to the two independent communication boards / modules configured on the gateway 3 side, which are respectively connected to different network directions.

[0034] "Communication networks in different directions" are used for the logical separation of business and management / backhaul. They can also be understood as two types of networks: southbound (field / distribution network side) and northbound (main station / public network side). They can also be implemented as two physically / logically isolated networks (private network vs. public network, narrowband control link vs. broadband backhaul link).

[0035] The two modules are decoupled from the service stack through the device master control / bus (such as UART / SPI / Ethernet MAC), and do not affect each other's carrying capacity and parameters (frequency band, power, protocol stack, APN, and authentication strategy can be configured independently).

[0036] Traditional carrier communication or public network communication is often subject to interference in complex electromagnetic environments such as substations and distribution rooms, resulting in data packet loss, large delays or communication failures, which affects the real-time analysis of line loss and operating status at the distribution area level.

[0037] The southbound communication network is a public network and the northbound communication network is a private network. There are many sensors in the southbound communication network. It is very expensive for the sensors to communicate using public network. Generally, the communication between gateway 3 and the terminal uses private network, while the communication between gateway 3 and the cloud server uses public network.

[0038] In this embodiment, the communication module accessing the southbound communication network is a 230MHz power grid communication module, and the communication module accessing the northbound communication network is a 4G CAT1 communication module.

[0039] The 230MHz power private network communication module operates in the power industry's own 230 MHz frequency band (or equivalent distribution private network frequency band). It has wide coverage, strong penetration, and stable link, making it suitable for control commands / short messages and wide-area low-speed access. It serves as a deterministic link for southbound transmission, used for "upload command triggering + end-side transmission of the latest value".

[0040] 4G CAT1 communication module: cellular public network LTE Cat.1, with moderate bandwidth, controllable latency, and mature pricing, suitable as a northbound bearer to transmit aligned and packaged data back to the main station, and to support remote maintenance / upgrades.

[0041] It should be noted that the user-side power data and the transformer-side power data include: Three-phase / single-phase voltage, current, active power, reactive power, and cumulative electrical energy.

[0042] Regardless of whether it's the user side or the transformer side, the terminal must acquire and form at least the following measurement set for the same time slice within one acquisition cycle: Voltage (U): For a three-phase system, it is Ua, Ub, Uc (or line voltage); for a single-phase system, it is U. Current (I): Ia, Ib, Ic for three phases, and I for single phase; Active power (P): can be Pa, Pb, Pc of each phase and / or the total P of the three phases; Reactive power (Q): can be Qa, Qb, Qc of each phase and / or the total of the three phases Q; Cumulative electrical energy (E): Includes at least the total positive active electrical energy (optionally extended to reverse, reactive energy in quadrants I / II, etc.).

[0043] The above measurements are read at the same acquisition moment, packaged into the same record and written into the data slot to avoid "splitting across time moments".

[0044] When the accessed object is a single-phase meter or a single-phase branch, only the single-phase field is filled; when it is a three-phase four-wire / three-phase three-wire system, the phase and / or total fields are filled.

[0045] Preferably, the reading and unit conversion are performed in accordance with the metering standard (such as the DI object of DLT 645), and the internal standardization is converted into an engineering quantity field, which is then uniformly entered into the alignment and packaging link.

[0046] It should be noted that an upload cycle includes multiple collection cycles.

[0047] To improve time resolution and reduce uplink and master station processing pressure, this embodiment decouples the acquisition cycle from the upload cycle, allowing multiple acquisition cycles to be included within one upload cycle. The acquisition terminal reads the measurement set from the meter at high frequency and writes it to the data slot only in an overwrite manner, always retaining the latest value; when the upload time is reached, the gateway 3 triggers a unified round of upload, realizing "high-frequency acquisition and throttling upload".

[0048] Under the decoupling mechanism described in this embodiment, preferably, the acquisition period Ta is configured to 5 s and the upload period Tu is configured to 1 min, so that n = Tu / Ta = 12, that is, the terminal completes 12 acquisitions before each round of upload, and only the latest value of the last acquisition is retained for the current round of upload.

[0049] Acquisition period Ta = 5s: Balancing second-level resolution with meter / RS-485 communication overhead, suitable for monitoring load fluctuations in most distribution areas.

[0050] Upload cycle Tu = 1min: Matches the minute-level statistics / analysis window of the main station to form a minute-level aligned snapshot sequence, which facilitates dynamic line loss, energy balance and anomaly diagnosis.

[0051] n = 12: Collect data 12 times per minute and upload the latest value once.

[0052] Depending on the on-site network quality and the load of the main station, the upload cycle Tu can be adjusted within a small range between 30 and 120 seconds, and the acquisition cycle Ta can be adjusted within a range between 2 and 10 seconds; after adjustment, the relationship of "one upload cycle contains multiple acquisition cycles" is still satisfied.

[0053] It should be noted that Gateway 3 reads the transformation ratio coefficient from the topology configuration table and performs transformation ratio correction on the power data based on the transformation ratio coefficient.

[0054] To ensure that the user-side and transformer-side measurements are performed on the same reference side for line loss and energy balance calculations, this embodiment maintains a topology configuration table on the gateway 3 side, records the transformation ratio coefficients associated with each meter / acquisition terminal, and performs transformation ratio correction on the power data before alignment and packaging.

[0055] Furthermore, Gateway 3 aligns the two types of electrical energy data in the time dimension, adds the meter address, and then packages them.

[0056] Input for Gateway 3: Collect data in the file Data.csv (containing fields such as msid, report_time, and pi). The topology configuration file Topology.csv contains information such as node and current_ratio.

[0057] Data processing flow of Gateway 3: Step S1: Read data Read the collected data table DF; Read the topology configuration table TOPO.

[0058] Step S2: Merge ratio information The variation coefficient current_ratio in the TOPO table is associated and merged with DF according to the node number (msid = node); The data table DF_merged containing current_ratio is obtained.

[0059] Step S3: Power data transformation ratio correction For each record, calculate the corrected active power: pi_corr = pi × current_ratio; Store the corrected result in a new column pi_corr.

[0060] Step S4: Time alignment processing (1-minute interval) For the collection time report_time of each record: Calculate the 1-minute time slot to which this time belongs: slot = floor(report_time, 1min); Calculate the time difference with the time slot: time_diff = |report_time - slot|.

[0061] Step S5: Select the data point closest to the time slot Group each node msid and each time slot, and select the record with the smallest time_diff as the valid data point for that time slot; The aligned data table DF_aligned is obtained.

[0062] It is understood that the same or similar parts in the above embodiments can be referred to each other, and the contents not described in detail in some embodiments can be referred to the same or similar contents in other embodiments.

[0063] It should be noted that in the description of this application, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, in the description of this application, unless otherwise stated, "a plurality of" means at least two.

[0064] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0065] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. An external data acquisition and transmission device for use in smart meters, characterized in that, include: User-side data acquisition terminal, transformer-side data acquisition terminal, and gateway; The user-side data acquisition terminal is connected to the user-side smart meter via an RS-485 interface; The transformer-side data acquisition terminal is connected to the transformer-side smart meter via an RS-485 interface; The user-side data acquisition terminal collects user-side power data based on the acquisition cycle and stores the collected user-side power data in the user-side data slot. The transformer-side data acquisition terminal acquires transformer-side electrical energy data based on the acquisition cycle and stores the acquired transformer-side electrical energy data in the transformer-side data slot. When the user-side data acquisition terminal receives the upload instruction sent by the gateway, it uploads the latest value in the user-side data slot to the gateway and clears the user-side data slot. When the transformer-side data acquisition terminal receives the upload command sent by the gateway, it uploads the latest value in the transformer-side data slot to the gateway and clears the transformer-side data slot. The gateway sends upload instructions to the user-side acquisition terminal and the transformer-side acquisition terminal based on the upload cycle; After receiving the power data uploaded by the user-side acquisition terminal and the transformer-side acquisition terminal, the two types of power data are aligned and packaged in the time dimension, and the packaged data is sent to the main station system.

2. The external data acquisition and transmission device for smart meters according to claim 1, characterized in that, The user-side data acquisition terminal acquires user-side power data through a first communication protocol; The transformer-side data acquisition terminal acquires electrical energy data from the transformer side through a first communication protocol; The user-side data acquisition terminal and the transformer-side data acquisition terminal upload data to the gateway through the second communication protocol.

3. The external data acquisition and transmission device for smart meters according to claim 1, characterized in that, The first communication protocol is the DLT 645 protocol; The second communication protocol is a gateway communication protocol.

4. The external data acquisition and transmission device for smart meters according to claim 1, characterized in that, Also includes: First communication module and second communication module; The first communication module and the second communication module are connected to communication networks in different directions.

5. The external data acquisition and transmission device for smart meters according to claim 1, characterized in that, The first communication module is a 230MHz power grid communication module, which is connected to the southbound communication network; The second communication module is a 4G CAT1 communication module, which is connected to the northbound communication network.

6. The external data acquisition and transmission device for smart meters according to claim 1, characterized in that, User-side power data and transformer-side power data include: Three-phase / single-phase voltage, current, active power, reactive power, and cumulative electrical energy.

7. The external data acquisition and transmission device for smart meters according to claim 1, characterized in that, An upload cycle includes multiple collection cycles.

8. The external data acquisition and transmission device for smart meters according to claim 7, characterized in that, The acquisition cycle is 5 seconds. The upload cycle is 1 minute.

9. The external data acquisition and transmission device for smart meters according to claim 1, characterized in that, The gateway reads the transformation ratio coefficient from the topology configuration table and performs transformation ratio correction on the power data based on the transformation ratio coefficient.

10. The external data acquisition and transmission device for smart meters according to claim 1, characterized in that, The gateway aligns the two types of electrical energy data in the time dimension, adds the meter address, and then packages them.

Images