Data acquisition system based on electric energy meter

Abstract

The utility model relates to a data acquisition system based on an electric energy meter, and the system comprises a plant station terminal host which is provided with at least one first communication interface; the N levels of downlink module hierarchical structures comprise a first level of downlink module hierarchical structure to an Nth level of downlink module hierarchical structure, each level of downlink module hierarchical structure comprises at least one downlink module, and at least one downlink module in the first level of downlink module hierarchical structure is connected with the plant station terminal host through a corresponding first communication interface, each downlink module is provided with at least one second communication interface, and N is a positive integer greater than or equal to 1; and the at least one electric energy meter is connected with the corresponding downlink module through the corresponding second communication interface. The scheme provided by the utility model is an efficient and flexible high-frequency acquisition scheme for the data of the electric energy meter, and can meet the requirements for high-frequency data acquisition in environments such as a novel electric power system scene and an electric power spot market.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of data acquisition, in particular to a data acquisition system based on an electric energy meter. BACKGROUND

[0002] In the field of current plant station automation systems, data acquisition is the core link to ensure efficient operation and management of the plant station. With the rapid development of the energy industry, especially the large-scale access of new energy and the rise of the electricity spot market, new challenges and higher requirements are put forward for the data acquisition of plant station terminals.

[0003] Traditional plant station terminals have obvious limitations in data acquisition, mainly in that the data acquisition frequency is low, usually once every 15 minutes. However, with the construction of new power systems and the continuous advancement of the double carbon goal, the proportion of wind power, photovoltaic and other new energy is gradually increasing, and the intermittency, randomness and volatility of new energy generation are becoming increasingly serious, requiring the gateway measurement system to achieve faster online acquisition and monitoring to accurately reflect the energy data and gateway operation status of each gateway measurement point in time, and to intelligently assist more detailed on-site operation and maintenance management.

[0004] At the same time, under the background of new power systems, the importance of emerging market entities such as virtual power plants and energy storage is increasingly prominent, and entities participating in frequency modulation, peak shaving and other auxiliary services have higher requirements for the timeliness and completeness of gateway measurement data. Especially in the electricity spot market, prices may fluctuate every minute or even every second according to real-time supply and demand, requiring plant stations to provide accurate information in a timely manner. However, under the traditional acquisition frequency, the plant station terminal cannot accurately capture the power change of new energy generation within the interval between two acquisitions, nor can it provide real-time operation data to support transaction decisions for electricity spot market participants, greatly affecting market transaction efficiency.

[0005] Although some plant station terminals have attempted to increase the acquisition frequency, it is still difficult to meet the actual needs of high-frequency acquisition. Moreover, in the face of the complex environment of new energy access and the electricity spot market, the problem of insufficient data acquisition accuracy and processing capacity is further magnified in the high-frequency acquisition scenario. However, compared to accuracy and processing capacity, the low acquisition frequency has become a more urgent problem, because only by achieving minute-level or even higher frequency acquisition can the urgent needs of new energy access and the development of the electricity spot market be met.

[0006] The existing plant station terminal data acquisition technology has been unable to meet the requirements of high-frequency data acquisition in the environment of new energy access and the electricity spot market, and there is an urgent need for a new type of plant station terminal technology that can achieve minute-level or even higher frequency acquisition to break this bottleneck. CONTENT OF THE INVENTION

[0007] In view of the above problems existing in the prior art, the application provides a data acquisition scheme based on an electric energy meter, which can meet the requirement for high-frequency data acquisition.

[0008] According to an aspect of the application, a data acquisition system based on an electric energy meter is provided, characterized in that it comprises:

[0009] A plant terminal host is provided with at least one first communication interface;

[0010] An N-level downlink module hierarchical structure comprises a first-level to an N-level downlink module hierarchical structure, each level of the downlink module hierarchical structure comprises at least one downlink module, at least one downlink module in the first-level downlink module hierarchical structure is connected with the plant terminal host through a respective corresponding first communication interface, wherein each downlink module is provided with at least one second communication interface, and N is a positive integer greater than or equal to 1; and

[0011] At least one electric energy meter is connected with a corresponding downlink module through a corresponding second communication interface.

[0012] The data acquisition system based on an electric energy meter of the application is a high-frequency electric energy meter data acquisition scheme which is efficient and flexible, and can meet the requirement for high-frequency data acquisition in a new power system scenario and an electric power spot market environment. BRIEF DESCRIPTION OF DRAWINGS

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the application, the drawings needed to be used in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art according to these drawings without departing from the scope of the application.

[0014] Figure 1 is a structural schematic diagram of an electric energy meter data acquisition system in the prior art.

[0015] Figure 2 is a structural schematic diagram of a data acquisition system based on an electric energy meter according to an embodiment of the application.

[0016] Figure 3 is a structural schematic diagram of a data acquisition system based on an electric energy meter according to another embodiment of the application.

[0017] Fig. 4(a) and Fig. 4(b) are structural schematic diagrams of a downlink module according to an embodiment of the application.

[0018] Figure 5 is a flow schematic diagram of a data acquisition method based on an electric energy meter according to an embodiment of the application. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person skilled in the art without creative work fall within the scope of protection of the present application.

[0020] Figure 1 is a structural schematic diagram of an existing power meter data acquisition system. Figure 1 The power meter data acquisition system shown is a traditional power meter data acquisition system based on a 15-minute acquisition cycle, which has been widely applied to various plant terminal. In the system architecture, the plant terminal host is equipped with n RS485 interfaces, and each interface is serially connected with k power meters through an RS485 bus. Under the standard configuration, when the serial port communication rate of the RS485 bus is set to 9600bps, the number of power meters that can be accessed is usually limited to a maximum of 32, due to the stability and efficiency of data transmission. For some old power meters that use a lower communication rate (such as 2400bps), the number of access will be further limited.

[0021] With the transformation of the power system to a new mode, especially the large-scale grid connection of new energy such as wind power and photovoltaic, and the introduction of new trading mechanisms such as the power spot market, the data acquisition requirements have changed significantly. Specifically, the types of power meters are increasingly diversified, and different manufacturers and models of power meters use different communication protocols and transmission rates, which puts higher requirements on the compatibility and flexibility of the data acquisition system. At the same time, due to the possibility of error retransmission during the acquisition process, as well as the potential impact of engineering wiring quality on the quality of RS485 transmission data (such as bit error rate), the traditional data acquisition system needs to be optimized in design to ensure the reliability and accuracy of data transmission. In addition, the amount of data transmitted by each power meter varies due to functional upgrades or changes in acquisition requirements, which poses a challenge to the processing capacity of the data acquisition system. Therefore, the traditional power meter data acquisition system based on a 15-minute acquisition cycle has been difficult to meet the urgent needs of the current power system for high-frequency and high-precision data acquisition.

[0022] In order to solve the problem of minute-level high-frequency acquisition and transmission efficiency of power meter voltage, current and other data, according to an aspect of the present application, a power meter-based data acquisition system is provided. Figure 2 is a structural schematic diagram of a power meter-based data acquisition system according to an embodiment of the present application. As shown in Figure 2As shown, the station terminal host is equipped with n RS485 interfaces, and each electric energy meter is allocated an independent RS485 bus to communicate with the station terminal host. This way, the electric energy meters enjoy independent RS485 bus communication paths, thus reducing the error rate and improving the data acquisition frequency. However, the number of RS485 ports of the station terminal host limits the number of electric energy meters that can be connected to the system, and as the number of electric energy meters increases, the complexity and maintenance difficulty of the system also increase.

[0023] According to another aspect of the present application, a data acquisition system based on electric energy meters is provided. Figure 3 is a structural schematic diagram of a data acquisition system based on electric energy meters according to another embodiment of the present application. As shown, Figure 3 The system includes a station terminal host, a downlink module, and one or more electric energy meters, wherein the electric energy meters are responsible for real-time metering of electric power parameters (such as voltage, current, electric energy, etc.), the station terminal host and the downlink module are used to collect and process the data of the electric energy meters in the station, and can exchange data with an electric energy metering master station or a station monitoring system.

[0024] In some embodiments, the station terminal host is provided with at least one first communication interface. The station terminal host is responsible for initiating data acquisition instructions, receiving and processing data from the downlink module, and performing preliminary processing or forwarding to the master station. In a specific embodiment, the first communication interface can be an Ethernet port. As shown, Figure 3 The station terminal host can communicate with the downlink module through the first communication interface.

[0025] In some embodiments, an N-level downlink module hierarchical structure is provided in the data acquisition system, including a first-level to an N-level downlink module hierarchical structure, where N is a positive integer greater than or equal to 1. Each level of the downlink module hierarchical structure includes at least one downlink module, and at least one downlink module in the first-level downlink module hierarchical structure is connected to the station terminal host through a respective first communication interface. Each downlink module is provided with at least one second communication interface. In a specific embodiment, the second communication interface can be an RS485 interface. As shown, Figure 3 Each downlink module can be equipped with k RS485 interfaces for directly connecting k electric energy meters, respectively.

[0026] In some embodiments, one second communication interface of each downlink module can connect one electric energy meter. In addition, to optimize the design of the station terminal, under the premise of ensuring that the bus driving capability of the second communication interface (such as the RS485 interface) is sufficient, the second communication interface of each downlink module is designed to be able to connect different numbers of electric energy meters in one-to-many series connection, where the specific connection form can refer to Figure 1The station terminal host computer is connected with the electric energy meter through the RS485 interface. This design not only effectively reduces the number of downlink modules and reduces the system cost, but also provides higher flexibility and convenience for field construction.

[0027] In the N-level downlink module hierarchical structure, each downlink module can be provided with a third communication interface and a fourth communication interface. In the second-level to N-1-level downlink module hierarchical structure, any downlink module is connected with the fourth communication interface of the corresponding upper-level downlink module through the third communication interface thereof, and is connected with the third communication interface of the corresponding lower-level downlink module through the fourth communication interface thereof. Any downlink module in the N-level downlink module hierarchical structure is connected with the fourth communication interface of the corresponding N-1-level downlink module through the third communication interface thereof. In one specific embodiment, the third communication interface and the fourth communication interface can be Ethernet ports. As shown in Figure 3 the downlink module 2 is connected with the fourth communication interface of the corresponding downlink module 1 through the third communication interface thereof, and is connected with the third communication interface of the corresponding downlink module 3 through the fourth communication interface thereof. The downlink module 3 is connected with the fourth communication interface of the corresponding downlink module 2 through the third communication interface thereof, and is connected with the third communication interface of the corresponding downlink module 4 through the fourth communication interface thereof, and so on.

[0028] As shown in Figure 3 , the station terminal host computer can further include a fifth communication interface, wherein the station terminal host computer communicates with the main station through the fifth communication interface. In one specific embodiment, the fifth communication interface can be an Ethernet port.

[0029] In one specific embodiment, as shown in Figure 3 , the station terminal host computer is configured with n Ethernet ports, which can be connected with n downlink modules at the same time. Each downlink module is configured with k RS485 expansion ports, which are connected with k electric energy meters in a point-to-point manner. The station terminal host computer can collect data of n x k electric energy meters. For the distribution of electric energy meters, if the number of electric energy meters connected by each Ethernet bus is within the carrying range of a single downlink module, the downlink module can be directly connected. If the number of electric energy meters exceeds the carrying capacity of a single downlink module, the downlink module can be expanded by cascading. Specifically, the downlink modules 1 to n are connected with m1 to mn downlink modules (m1, m2,..., mn represent the number of downlink modules expanded by each Ethernet port through cascading) through cascading. If each downlink module is connected with k electric energy meters, the amount of electric energy meter data that can be collected by the station terminal host computer will be expanded to (m1+m2+...+mn) x k electric energy meters.

[0030] From the aspect of communication performance, the typical baud rate of the electric energy meter RS485 bus is 9600bps, while the communication rate of the fast Ethernet is 100Mbps, and the bandwidth is more than 10,000 times of the RS485 bus. Compared with the background technical solution, the collection frequency is no longer the bottleneck of the present solution. By using the present solution, even when the number of electric energy meters is large in a large substation, high-frequency collection at a minute level or even a sub-minute level can be achieved.

[0031] From the aspect of wiring optimization, according to the minute-level collection cycle, the present solution takes a more efficient wiring strategy according to the distribution area of the actual electric energy meter: each regional downlink module is connected to the electric energy meters in the region through the second communication interface. When the single downlink module reaches the upper limit of the load, it is seamlessly expanded through cascading, avoiding the wiring confusion and signal interference caused by the explosive growth of the number of devices. In the present application, the substation terminal host only needs to be connected to each downlink module through n Ethernet ports, which significantly reduces the wiring complexity, reduces the amount of cable used, and simplifies the wiring structure.

[0032] The optimized wiring solution provided in the present application can improve the flexibility of the networking architecture by increasing the downlink module and the expansion port. At the same time, the system can fully utilize the high-speed communication capability of the Ethernet to expand the network scale, and further enhance the connection capability of the expansion port with the help of the wide applicability of the RS485 bus. The system designed in the present application can maintain efficient and stable operation when facing large-scale and widely-covered electric energy meter data collection tasks, not only improving the data collection efficiency and data processing capability, but also effectively reducing the wiring cost and subsequent maintenance difficulty.

[0033] In some embodiments, the main functions of the downlink module include: 1, cascading between downlink modules; 2, completing the conversion from a preset communication protocol (including a standard communication protocol or a custom communication protocol) to a meter reading protocol of an electric energy meter, serving as a key networking connection node to realize high-speed connection and communication with the electric energy meter. FIG. 4(a) and FIG. 4(b) are structural schematic diagrams of a downlink module according to an embodiment of the present application. As shown in FIG. 4(a) and FIG. 4(b), the downlink module includes a third communication interface and a fourth communication interface (embodied as two Ethernet ports in FIG. 4) and a second communication interface (embodied as RS485 in the figure). As shown in FIG. 4(a), the downlink module further includes a network switch, an MCU (Microcontroller Unit), an SPI (Serial Peripheral Interface) serial port expansion chip and an RS485 transceiver, and the two Ethernet ports, the network switch, the MCU, the SPI serial port expansion chip and the RS485 transceiver and the RS485 interface are sequentially connected. As shown in FIG. 4(b), the downlink module further includes an Ethernet transceiver, an MCU, an SPI serial port expansion chip and an RS485 transceiver, and the two Ethernet ports, the Ethernet transceiver, the MCU, the SPI serial port expansion chip and the RS485 transceiver and the RS485 interface are sequentially connected.

[0034] In some embodiments, the 485 transceiver receives meter reading messages from the electric energy meter and delivers the messages to the MCU module. The MCU module then parses the message content encapsulated by the meter reading protocol (such as DL / T 645, DL / T 698.45, DL / T 860, IEC1107, IEC 62056 (DLMS), EDMI, ELSTER, etc.) of the electric energy meter, extracts the key electric energy data therefrom, re-encapsulates the extracted data in the format of a standard communication protocol or a custom communication protocol, forms a new data packet, and transmits the data packet to the network switch through the Ethernet transceiver or directly, and then to the terminal host computer of the power station. The entire process realizes the conversion from the meter reading protocol of the electric energy meter to the standard communication protocol or the custom communication protocol, so that the data of the electric energy meter can be efficiently transmitted and shared through the network, thereby realizing the functions of remote meter reading, data monitoring and intelligent management, etc.

[0035] On the basis of the above-mentioned electric energy meter-based data acquisition system, according to another aspect of the present application, an electric energy meter-based data acquisition method is provided. Figure 5 FIG. 1 is a flowchart of an electric energy meter-based data acquisition method according to an embodiment of the present application. As shown in FIG. 1, the method includes the following steps. Figure 5

[0036] ​Step S501, the station terminal host sends a data collection instruction to a target electric energy meter through the N-level downlink module hierarchical structure.

[0037] In some embodiments, the station terminal host sends the data collection instruction to the downlink module through the first communication interface, wherein the data collection instruction can adopt a standard communication protocol or a custom communication protocol. In some embodiments, when the second communication interface of the downlink module is connected to one electric energy meter, the data collection instruction includes archive information, which includes the number of the downlink module directly connected to the target electric energy meter and the number of the second communication interface corresponding to the target electric energy meter. In other embodiments, when the second communication interface of the downlink module is designed to be connected to different numbers of electric energy meters in a one-to-many manner, the archive information in the data collection instruction includes the number of the downlink module directly connected to the target electric energy meter, the number of the second communication interface corresponding to the target electric energy meter, and the number of the target electric energy meter.

[0038] In a specific embodiment, the downlink module can have two encoding discs, which can dial a two-digit number from 00 to 99. The archive information of the electric energy meter records the number of the downlink module, the number of the second communication interface corresponding to the electric energy meter, and other information of the electric energy meter. The data collection instruction sent by the station terminal host to the downlink module through the first communication interface contains the archive information of the electric energy meter, which corresponds to the specific downlink module and the electric energy meter. When the data packet is returned, the archive information of the electric energy meter is also included, so that the data and the electric energy meter can be corresponded. For example, the archive information 01-5, 01 can represent the downlink module numbered 01, and 5 can represent the second communication interface numbered 5 of the downlink module. In the case of the first communication interface being an Ethernet port, the terminal host sends instructions to the downlink module through Ethernet (IP). The IP address and the number of the downlink module can be the same, such as the downlink module number being 12 and the IP being 192.168.6.12, or they can be different but can be mapped one by one.

[0039] Step S502, the specified downlink module in the N-level downlink module hierarchical structure parses the data collection instruction into a meter reading message according to a preset protocol, and sends the meter reading message to the target electric energy meter.

[0040] In some embodiments, after the N-level downlink module hierarchical structure receives the instruction from the station terminal host, a specified downlink module processes the instruction. The specified downlink module parses the data collection instruction into a meter reading message according to a preset protocol, and sends the meter reading message to the target electric energy meter according to the archive information of the electric energy meter. In a specific embodiment, the specified downlink module can be any downlink module in the N-level downlink module hierarchical structure, or it can be the downlink module directly connected to the target electric energy meter. The preset protocol includes a standard communication protocol or a custom communication protocol.

[0041] Step S503, the destination electric energy meter performs a data collection task based on the meter reading message;

[0042] Step S504, the destination electric energy meter sends the collected data to the designated downlink module.

[0043] In some embodiments, after the electric energy meter receives the meter reading message, it performs a corresponding data collection task and returns the collected data to the downlink module through the second communication interface.

[0044] Step S505, the designated downlink module encapsulates the data collected by the destination electric energy meter according to a preset protocol and sends the encapsulated data to the substation terminal host or to the upper-level downlink module for transfer.

[0045] Step S506, the substation terminal host receives and processes the data collected by the destination electric energy meter.

[0046] In some embodiments, the designated downlink module reads the meter reading result returned by the electric energy meter, extracts the data content therein and re-encapsulates it according to a preset protocol format to form a new data packet. The designated downlink module sends the encapsulated data packet back to the substation terminal host through Ethernet or to the upper-level downlink module for transfer. The substation terminal host receives and processes the data packet, performs data analysis, verification and integration.

[0047] The above describes the embodiments of the present application in detail. The principles and implementation modes of the present application are described by applying specific examples. The above description of the embodiments is only used to help understand the scheme of the present application and its core idea. Meanwhile, any changes or modifications made by those skilled in the art based on the specific implementation modes and application scope of the present application are within the scope of protection of the present application. In summary, the content of the present description should not be understood as a limitation of the present application.

Claims

1. An electricity meter based data acquisition system, characterized by, The system comprises: a station terminal host configured with at least one first communication interface; an N-level downlink module hierarchical structure, comprising a first-level to an N-level downlink module hierarchical structure, each level of the downlink module hierarchical structure comprising at least one downlink module, at least one downlink module in the first-level downlink module hierarchical structure being connected to the station terminal host via a respective first communication interface, wherein each downlink module is configured with at least one second communication interface, and N is a positive integer greater than or equal to 1; and at least one electric energy meter connected to a corresponding downlink module via a corresponding second communication interface. Each downlink module is configured with a third communication interface and a fourth communication interface, in the second-level to the N-1-level downlink module hierarchical structure, any downlink module is connected to a corresponding upper-level downlink module via its third communication interface and to a corresponding lower-level downlink module via its fourth communication interface, and any downlink module in the N-level downlink module hierarchical structure is connected to a corresponding N-1-level downlink module via its third communication interface.

2. The system of claim 1, wherein, The station terminal host is further configured with at least one fifth communication interface for data communication with a master station.

3. The system of claim 2, wherein, The first communication interface, the third communication interface, the fourth communication interface and the fifth communication interface comprise an Ethernet port, and the second communication interface comprises an RS485 interface.

4. The system of claim 3, wherein, One second communication interface of each downlink module is connected to one or more electric energy meters.

5. The system of claim 1, wherein, 6. The system according to any one of claims 1 to 5, wherein the station terminal host is configured to send a data collection instruction to a target electric energy meter among the electric energy meters via the N-level downlink module hierarchical structure via the first communication interface, and receive data collected by the electric energy meters via the N-level downlink module hierarchical structure; any downlink module in the N-level downlink module hierarchical structure is configured to relay the data collection instruction and the data collected by the electric energy meters, a designated downlink module in the N-level downlink module hierarchical structure is configured to parse the data collection instruction into a meter reading message and send the meter reading message to the target electric energy meter, and encapsulate the data collected by the target electric energy meter according to a preset protocol and send the encapsulated data to the station terminal host or to an upper-level downlink module for relaying; and the at least one electric energy meter is configured to perform a data collection task according to the meter reading message and send the collected data to a directly connected downlink module. The designated downlink module is a downlink module directly connected to the target electric energy meter. The data collection instruction comprises profile information, and the profile information comprises a number of the downlink module directly connected to the target electric energy meter and a number of the second communication interface corresponding to the target electric energy meter.

7. The system of claim 6, wherein, The preset protocol comprises a standard communication protocol or a custom communication protocol.

8. The system of claim 7, wherein, The station terminal host processes the data collected by the target electric energy meter in a manner comprising parsing, checking and integrating.

9. The system of claim 6, wherein, ​ 10. The system of claim 6, wherein, ​

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