Dispersed monitoring system for secondary power distribution network

Abstract

The invention discloses a distributed monitoring system for a secondary power distribution network, and relates to the technical field of power grid detection, the system comprises a cloud server and a monitoring module configured for each transformer node in a target secondary power distribution network, the transformer node comprises a transformer and a load, the monitoring module comprises a data acquisition unit, a microcontroller and a control switch; for each monitoring module, the control switch is connected between the transformer and the load; the data acquisition unit acquires working data of transformer nodes in real time and sends the working data to the microcontroller; the microcontroller judges whether the transformer node breaks down or not according to the working data, if yes, power is supplied to the load again without exceeding the set number of times through the control switch, and if the transformer node still breaks down after the power is supplied again without exceeding the set number of times, it is judged that the transformer node has a non-surge type fault; and sending the non-surge fault information of the transformer node to a cloud server. The fault detection efficiency can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of power grid detection, and in particular to a decentralized monitoring system for a secondary power distribution network. Background Art

[0002] Power distribution relies mainly on centralized systems such as Supervisory Control And Data Acquisition (SCADA) systems, which are mainly focused on high and medium voltage systems, while low voltage systems such as secondary distribution systems have not yet become a focus. These systems prioritize automation, control, monitoring and centralized functional parameters of large power grids. Secondary distribution systems have not yet been considered primarily for automation, control and power parameter data collection. The limited automation that has been completed at this level is also centralized, but due to the complex distributed nature of secondary distribution systems, centralized automation and control systems cannot achieve effective monitoring of secondary distribution systems. Fault monitoring has improved through the transmission of basic levels of fault indication, limited response levels and some key parameters to central systems through intelligent electronic devices (IEDs) and special smart relays, but the operating costs of secondary distribution are still high, so fault monitoring solutions for secondary distribution systems still need to be improved. Summary of the invention

[0003] The purpose of the present application is to provide a decentralized monitoring system for a secondary power distribution network, which can improve the efficiency of fault detection.

[0004] To achieve the above objectives, this application provides the following solutions:

[0005] In a first aspect, the present application provides a decentralized monitoring system for a secondary distribution network, comprising: a cloud server and a monitoring module configured for each transformer node in a target secondary distribution network, each of the monitoring modules is communicatively connected to the cloud server, the transformer node comprises a transformer and a load, the monitoring module comprises a data acquisition unit, a microcontroller and a control switch; for each monitoring module, the control switch is connected between the transformer and the load, and the data acquisition unit and the control switch are both connected to the microcontroller;

[0006] The data acquisition unit is used to collect the working data of the transformer node in real time and send the working data to the microcontroller;

[0007] The microcontroller is used to determine whether the transformer node has a fault based on the working data. If a fault occurs, the microcontroller controls the control switch to re-power the load no more than a set number of times. If the transformer node is still faulty after re-powering no more than a set number of times, it is determined that a non-surge fault exists in the transformer node, and the non-surge fault information of the transformer node is sent to the cloud server.

[0008] Optionally, the operating data includes voltage and current output by the transformer.

[0009] Optionally, the microcontroller includes a fault judgment unit, which is used to calculate the instantaneous distributed power based on the voltage and the current collected in real time. If the instantaneous distributed power exceeds a preset safety threshold, it is determined that there is a fault in the transformer node.

[0010] Optionally, the fault judgment unit is also used to record the fault type of the current fault as a non-surge fault if the transformer node still has a fault after no more than a set number of power re-powerings, and to record the fault type of the current fault as a surge fault if the transformer node fault disappears after no more than a set number of power re-powerings.

[0011] Optionally, the set number of times is 3 times, and the load is powered off for 30 seconds before each power supply is re-supplied.

[0012] Optionally, the monitoring module further includes a GSM module, and the GSM module is used to send the non-surge fault information of the transformer node to the cloud server.

[0013] Optionally, the microcontroller includes a theft detection unit, which is used to determine the distributed energy of the transformer node based on the voltage and the current collected in real time, and issue a theft warning message based on the energy difference between the distributed energy and the consumed energy if the energy difference exceeds a difference threshold.

[0014] Optionally, the monitoring module further includes an electric meter connected to the load, and the theft detection unit is further configured to determine the consumed energy based on the electric energy collected by the electric meter.

[0015] Optionally, the theft detection unit is further configured to send the theft warning information to the cloud server.

[0016] Optionally, the control switch is a relay.

[0017] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0018] The present application provides a decentralized monitoring system for a secondary distribution network, in which a monitoring module is configured for each transformer node in a target secondary distribution network. A microcontroller in the monitoring module determines whether a transformer node fails based on real-time collected working data, and re-powers the load by controlling a switch for no more than a set number of times. If the fault disappears, the fault processing is completed, thereby improving the fault response speed. If the fault still exists, non-surge fault information is sent to a cloud server, thereby avoiding bandwidth congestion caused by sending all fault information to the cloud server, and only transmitting faults that cannot be processed by the transformer node to the cloud server, thereby improving bandwidth utilization and thus improving fault detection efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A schematic diagram of the structure of a decentralized monitoring system for a secondary power distribution network provided in one embodiment of the present application;

[0021] Figure 2 A schematic diagram of a workflow of a decentralized monitoring system for a secondary power distribution network provided in one embodiment of the present application. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0023] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0024] The present application provides a decentralized monitoring system for a secondary distribution network, the decentralized monitoring system for a secondary distribution network comprising: a cloud server and a monitoring module configured for each transformer node in a target secondary distribution network, each of the monitoring modules being communicatively connected to the cloud server, the transformer node comprising a transformer and a load, the monitoring module comprising a data acquisition unit, a microcontroller and a control switch; for each monitoring module, the control switch is connected between the transformer and the load, and the data acquisition unit and the control switch are both connected to the microcontroller.

[0025] The data acquisition unit is used to acquire the working data of the transformer node in real time and send the working data to the microcontroller.

[0026] The microcontroller is used to determine whether the transformer node has a fault based on the working data. If a fault occurs, the microcontroller controls the control switch to re-supply the load no more than a set number of times. If the transformer node is still faulty after re-supplying no more than a set number of times, it is determined that a non-surge type fault exists in the transformer node, the control switch is disconnected, and the non-surge type fault information of the transformer node is sent to the cloud server.

[0027] In an exemplary embodiment, the working data includes the voltage and current output by the transformer, and the working data also includes real-time data of key parameters such as power factor, AC wave frequency, load size, potential surge conditions, etc. The working data is collected by various sensors in the data acquisition unit.

[0028] The control switch is a relay. The cloud server is a central server of each transformer node.

[0029] Each transformer node is an autonomous node that monitors the direct electrical environment within the transformer distribution area. The relationship between each transformer node and the monitoring module is as follows: Figure 1 As shown, the microcontroller at a specific node collects and acquires data for that specific node without using centralized control. Since data processing is performed in a decentralized manner, the system is able to detect danger more quickly while allowing the corresponding units of each transformer node to operate autonomously, thereby improving the reliability of the entire network. In addition, the relay activation and blocking mechanism facilitates the rapid disconnection of faulty components, effectively limiting damage to the surrounding network.

[0030] Each transformer node is embedded with an independent data acquisition unit-repeater-microcontroller device, which enables localized data acquisition and recovery. The transformer node configuration means that each transformer node can identify and control faults independently of the central structure. Other advantages of this hardware layered structure include enhanced robustness and redundancy: if one transformer node fails or requires maintenance, other transformer nodes will not be disturbed and the network can continue to work with appropriate interference levels. In addition, the modular composition makes upgrades easier because the insertion of new transformer nodes will not have much impact on the current configuration. The decentralized model also reduces the dependence on physical facilities, so the system is very suitable for semi-urban areas where resources are scarce or it is difficult to expand the physical network.

[0031] In an exemplary embodiment, the microcontroller includes a fault judgment unit, which is used to calculate the instantaneous distributed power based on the voltage and the current collected in real time. If the instantaneous distributed power exceeds a preset safety threshold, it is determined that there is a fault at the transformer node.

[0032] In an exemplary embodiment, the fault judgment unit is further configured to record the fault type of the current fault as a non-surge fault if the transformer node still has a fault after no more than a set number of repowering, and to record the fault type of the current fault as a surge fault if the transformer node fault disappears after no more than a set number of repowering. The working process of each transformer node is as follows: Figure 2 shown.

[0033] In an exemplary embodiment, the set number of times is 3 times, and the load is powered off for 30 seconds before each power supply is re-supplied.

[0034] Surge faults are usually intermittent, caused by overload or short circuit, and are automatically handled by each transformer node in the fault classification algorithm in the microcontroller. The fault classification algorithm has a time-based function that detects surge faults within ninety seconds and attempts to correct and isolate them. In the case of non-surge type faults, that is, faults that require manual inspection and correction, the system will mark them for review after a short time based on the location and load variables when the fault occurred. By classifying faults in this way, surge type faults and non-surge type faults can be managed in an organized manner, where surge type faults are handled as emergency faults and non-surge type faults are handled in the order deemed necessary.

[0035] This application will be automatically processed by the system within 90 seconds. For non-surge faults that cannot be cleared after three repair attempts, the system will report it to the cloud server, indicating that manual inspection is required.

[0036] The instantaneous distributed power is calculated according to the formula P(t)=V×I(t), where P(t) represents the instantaneous distributed power at time t, V is not a fixed voltage value but a real-time measurement value, and I(t) is the real-time measured current.

[0037] This fault classification algorithm effectively distinguishes between surge faults that can be managed automatically and non-surge faults that may require manual intervention. The algorithm relies on real-time data from step 1, ensuring the accuracy of the classification, thereby reducing downtime and enhancing the reliability of the entire network.

[0038] In an exemplary embodiment, the transformer is a 11 kV to 220 V / phase transformer.

[0039] In an exemplary embodiment, the microcontroller includes a theft detection unit, which is used to determine the distributed energy of the transformer node based on the voltage and the current collected in real time, and issue a theft warning message based on the energy difference between the distributed energy and the consumed energy if the energy difference exceeds a difference threshold.

[0040] In an exemplary embodiment, the monitoring module further includes an electric meter connected to the load, and the theft detection unit is further configured to determine the consumed energy based on the electric energy collected by the electric meter.

[0041] In an exemplary embodiment, the theft detection unit is further configured to send the theft warning information to the cloud server.

[0042] In an exemplary embodiment, the monitoring module further includes a Global System for Mobile Communications (GSM) module, and the GSM module is used to send the non-surge fault information of the transformer node to the cloud server.

[0043] The GSM module is also used to send power metering information to the cloud server. The data transmitted by the GSM module to the cloud server is selective. Taking faults as an example, surge faults and the most serious parameters (such as power supply or load changes) will be sent to the cloud server. This selective data transmission helps save bandwidth, thereby reducing the amount of data sent via GSM and only sending the most necessary information. Each transformer's microcontroller is connected to a GSM module, which can upload data to the cloud server in real time, thereby enabling remote access to information. This design is very valuable in areas with infrequent network coverage because it ensures that only critical information is sent, allowing the system to continue to operate in a low-bandwidth environment.

[0044] The decentralized monitoring system for the secondary power distribution network of the present application also includes a DC converter and a buck converter. The DC converter converts the AC power output by the transformer into a DC potential to power the controller, and the buck converter steps down the DC power output by the DC converter to power the GSM. The DC converter outputs a voltage of 12V, and the buck converter outputs a voltage of 3.7V.

[0045] Another important aspect of this application is to detect power theft and power loss in the system through power-based meter data, monitoring the load and distributed output indicators of individual transformers, the scope of which is to find the difference between the energy provided and calculate its capacity. Any significant gap between the two measurements exceeding a certain threshold will trigger a theft warning or line loss, indicating a poor condition in the distribution system. Curbing the frequent power attacks in these areas helps to take proactive measures in time to minimize losses. In the decentralized monitoring framework, the transformer becomes an intelligent resource for the distribution area it controls, thereby enhancing the localized system during power outages.

[0046] Compared with the centralized system, the decentralized monitoring system for the secondary distribution network enables each transformer node in the distribution network to autonomously monitor, detect and manage power faults. Among them, the automatic response of the relay should correct the surge fault within 90 seconds, while the non-surge fault is reported to the cloud server after a short delay and set time, and updated to the central database.

[0047] This application uses GSM communication, which allows to send some power parameters at the same time as the fault report without saturating the bandwidth. The system will also be able to monitor the power consumption of each transformer in the future and compare the power generation and consumption to detect theft and power loss. This decentralized and modular approach reduces response time, costs and the amount of fixed infrastructure, increasing reliability and adaptability. The system will especially improve winterization due to efficient power management and self-correction of faults.

[0048] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0049] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A decentralized monitoring system for a secondary power distribution network, characterized in that: The decentralized monitoring system for a secondary power distribution network comprises: a cloud server and a monitoring module configured for each transformer node in a target secondary power distribution network, each of the monitoring modules is in communication connection with the cloud server, the transformer node comprises a transformer and a load, the monitoring module comprises a data acquisition unit, a microcontroller and a control switch; for each monitoring module, the control switch is connected between the transformer and the load, and the data acquisition unit and the control switch are both connected to the microcontroller; The data acquisition unit is used to collect the working data of the transformer node in real time and send the working data to the microcontroller; The microcontroller is used to determine whether the transformer node has a fault based on the working data. If a fault occurs, the microcontroller controls the control switch to re-power the load no more than a set number of times. If the transformer node is still faulty after re-powering no more than a set number of times, it is determined that a non-surge fault exists in the transformer node, and the non-surge fault information of the transformer node is sent to the cloud server.

2. The decentralized monitoring system for a secondary power distribution network according to claim 1, characterized in that: The operating data includes the voltage and current output by the transformer.

3. The decentralized monitoring system for a secondary power distribution network according to claim 2, characterized in that: The microcontroller includes a fault judgment unit, which is used to calculate the instantaneous distribution power according to the voltage and the current collected in real time. If the instantaneous distribution power exceeds a preset safety threshold, it is determined that there is a fault in the transformer node.

4. The decentralized monitoring system for a secondary power distribution network according to claim 3, characterized in that: The fault judgment unit is also used to record the fault type of the current fault as a non-surge fault if the transformer node still has a fault after no more than a set number of power re-powerings, and to record the fault type of the current fault as a surge fault if the transformer node fault disappears after no more than a set number of power re-powerings.

5. The decentralized monitoring system for a secondary power distribution network according to claim 1, characterized in that: The set number of times is 3 times, and before each power supply is re-energized, the load is powered off for 30 seconds.

6. The decentralized monitoring system for a secondary power distribution network according to claim 1, characterized in that: The monitoring module also includes a GSM module, and the GSM module is used to send the non-surge fault information of the transformer node to the cloud server.

7. The decentralized monitoring system for a secondary power distribution network according to claim 2, characterized in that: The microcontroller includes a theft detection unit, which is used to determine the distributed energy of the transformer node based on the voltage and the current collected in real time, and to issue a theft warning message based on the energy difference between the distributed energy and the consumed energy if the energy difference exceeds a difference threshold.

8. The decentralized monitoring system for a secondary power distribution network according to claim 7, characterized in that: The monitoring module further includes an electric meter connected to the load, and the theft detection unit is further configured to determine the consumed energy based on the electric energy collected by the electric meter.

9. The decentralized monitoring system for a secondary power distribution network according to claim 7, characterized in that: The theft detection unit is also used to send the theft warning information to the cloud server.

10. The decentralized monitoring system for a secondary power distribution network according to claim 1, characterized in that: The control switch is a relay.

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