Medium-voltage line on-line monitoring and fault detection early warning system based on Internet of Things

Abstract

The invention discloses a medium-voltage line on-line monitoring and fault detection early warning system based on the Internet of Things, which belongs to the field of medium-voltage line detection and comprises a medium-voltage standardization module, an Internet of Things module and a one-way communication isolation module, the power distribution automation service comprises power distribution data monitoring, fault information monitoring, power distribution data reporting and standardized conversion of other accessed equipment; and the Internet of Things module is used for establishing an Internet of Things channel and transmitting the power data through the Internet of Things channel. Effective physical isolation of data is achieved through the one-way communication isolation module, and data leakage is prevented.

Description

Technical Field

[0001] The present invention belongs to the field of medium voltage line detection, and in particular relates to an Internet of Things-based medium voltage line online monitoring and fault detection and early warning system. Background Art

[0002] As an important part of the power grid, the distribution network directly faces power customers and is closely related to the production and life of the general public. It is an important infrastructure for safeguarding and improving people's livelihood, and is the most intuitive object for customers to feel and experience the power grid services. At present, the development of the distribution network is unbalanced and insufficient, and it can no longer fully meet the needs of economic and social development. To this end, the distribution network needs to introduce new technologies and concepts such as "big cloud, things, mobility, intelligence and chain", and strive to create a distribution Internet of Things ecosystem oriented to the deep integration of "distribution network + Internet of Things", which will essentially improve the construction, operation and maintenance, and management level of the distribution network, promote continuous innovation in business models, service models and management models, and support the rapid development of digital power grids.

[0003] At present, the existing models and standards in the distribution network have the following problems: the existing models and standards cannot well support the actual application needs of first-class distribution network related systems; the information models followed by different systems in the distribution network are not unified, and the extension of the same model is not standardized; the data interaction between the existing distribution network systems has not formed a unified standard specification. On this basis, how to unify the online monitoring and early warning data of medium-voltage lines has become a problem to be solved. Summary of the invention

[0004] In response to the above technical problems, the present invention discloses a medium-voltage line online monitoring and fault detection and early warning system based on the Internet of Things, including a medium-voltage standardization module, an Internet of Things module, and a one-way communication isolation module. The medium-voltage standardization module is used for distribution automation services, and the distribution automation services include distribution data monitoring, fault information monitoring, distribution data reporting, and standardized conversion of other connected devices; the Internet of Things module is used to establish an Internet of Things channel and transmit power data through the Internet of Things channel.

[0005] The one-way communication isolation module is used to determine the direction of information transmission between the medium voltage standardization module and the Internet of Things module, and transmits information one-way from the medium voltage standardization module to the Internet of Things module to block the communication.

[0006] The Internet of Things module includes a communication unit and an expansion unit. The communication unit is used to establish an Internet of Things security channel for encrypted transmission, and the expansion unit is used for extended access to other Internet of Things modules.

[0007] Furthermore, the medium voltage standardization module includes a collection unit, a monitoring unit, and a standardization unit. A real-time channel is established between the units of the medium voltage standardization module, and data is received and sent through the real-time channel; the collection unit is used to collect power information with timing information in the circuit, send the power information data to the detection unit through the real-time channel, monitor the power information data through the monitoring unit, and mark the monitoring results in the timing interval of the power information; the standardization unit is used to report data on alarm information and fault information, and the fault information includes data waveform and corresponding monitoring results.

[0008] Furthermore, the unidirectional communication isolation module is arranged between the medium voltage standardization module and the Internet of Things module, and is used for unidirectional transmission of data from the medium voltage standardization module to the Internet of Things module. Two data transceiver buffer areas are managed in the unidirectional communication isolation module, one for receiving data from the medium voltage standardization module, and the other for copying data from the medium voltage standardization module and sending it to the Internet of Things module. When copying data, it is necessary to verify the integrity of the data. When verifying the integrity of the data, the public key information of the medium voltage standardization module preset in the unidirectional communication isolation module is first used to verify the certificate signature of the medium voltage standardization module, and a session key is negotiated through a key, and a key is derived from the session key. The derived key is used to verify the integrity of each received data.

[0009] Furthermore, when the Internet of Things module sends data in the data transmission and reception buffer area, it first determines whether there is a collection unit port number in the data header. If there is a collection unit port number, the Internet of Things module modifies the data header to the Internet of Things module communication unit number + collection unit port number when sending the data; if there is no collection unit port number, the Internet of Things module needs to generate a virtual port number for the data; the Internet of Things uses the MQTT protocol to send data to the cloud.

[0010] Furthermore, when there are other terminals that do not have the Internet of Things function accessing the system, it is necessary to perform standardized conversion of the transmission protocol of other terminals through the standardization unit of the medium voltage standardization module. Other terminals send data to the standardization unit, and then send it to the Internet of Things module through the standardization unit to enable other terminals to have the Internet of Things function. When the data sent by other terminals contains the port number of the collection unit, the Internet of Things module will perform virtualization.

[0011] Furthermore, the medium voltage standardization module also includes an equipment status detection unit, an equipment mechanical characteristics monitoring unit, and an early fault insulation monitoring unit. The equipment status detection unit is used to monitor the elbow head temperature monitoring, cabinet temperature measurement, water immersion, smoke, and partial discharge sensor data in the ring network cabinet / distribution station, and report the set abnormal data through the standardization unit; the equipment mechanical characteristics monitoring unit is used to analyze the current waveform when the switch opening and closing coil is actuated, identify the characteristics of the current waveform, and reflect the conditions of the electromagnet, the tripping device, and the operating mechanism; the early fault insulation monitoring unit is used to monitor early insulation faults and analyze the causes of the faults.

[0012] The workflow of the early fault monitoring unit includes: Step S1, collecting instantaneous fault waveforms of the cable lines of the ring main unit, switchgear, cable lines, pole switches, and overhead lines through the collection unit of the medium voltage standardization module.

[0013] Step S2, using the early fault monitoring unit to perform disturbance analysis on the effective value amplitude of the collected current waveform, and judging the single-phase grounding through parameter identification, phase asymmetry method, and zero-sequence power method.

[0014] Step S3, record the number of faults for the cable numbers of the cables with cable fault grounding, analyze the cable fault trend, and conduct regional inspection of single grounding through artificial intelligence algorithm.

[0015] Compared with the prior art, the present invention has the following advantages: (1) the present invention realizes effective physical isolation of data through a one-way communication isolation module to prevent data leakage; (2) the monitoring and alarm of medium-voltage lines are realized by collecting and analyzing fault data; (3) by setting up standardized units, it is easy to expand other Internet of Things modules, providing ease of use and scalability. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The present invention is a schematic block diagram of the system.

[0017] Figure 2 This is an exemplary flowchart of the operation of the early fault monitoring unit of the present invention. DETAILED DESCRIPTION

[0018] Example: Figure 1 As shown, a medium-voltage line online monitoring and fault detection and early warning system based on the Internet of Things includes a medium-voltage standardization module, an Internet of Things module, and a one-way communication isolation module. The medium-voltage standardization module is used for distribution automation business, and the distribution automation business includes distribution data monitoring, fault information monitoring, distribution data reporting, and standardized conversion of other connected devices; the Internet of Things module is used to establish an Internet of Things channel and transmit power data through the Internet of Things channel.

[0019] The unidirectional communication isolation module is used to determine the direction of information transmission between the medium voltage standardization module and the Internet of Things module, and transmits information unidirectionally from the medium voltage standardization module to the Internet of Things module to block the communication.

[0020] The IoT module includes a communication unit and an expansion unit. The communication unit is used to establish an IoT security channel for encrypted transmission, and the expansion unit is used for extended access to other IoT modules.

[0021] The medium voltage standardization module includes an acquisition unit, a monitoring unit, and a standardization unit. A real-time channel is established between the units of the medium voltage standardization module, and data is received and sent through the real-time channel. The acquisition unit is used to collect power information with timing information in the circuit, send the power information data to the detection unit through the real-time channel, monitor the power information data through the monitoring unit, and mark the monitoring results in the timing interval of the power information; the standardization unit is used to report data on alarm information and fault information, and the fault information includes data waveform and corresponding monitoring results.

[0022] In this embodiment, the core function of is to determine whether to generate early warning alarm information and fault information according to the monitoring results of the monitoring unit and the pre-set early warning value.

[0023] First, it continuously receives power information monitoring results from the monitoring unit. These monitoring results include real-time values ​​of various key parameters, such as current, voltage, power, etc., as well as changes in the power information time series interval.

[0024] Next, the received monitoring results will be compared with the pre-set warning values, which are usually determined based on the normal operating range of the medium-voltage line, safety standards, and past operating experience.

[0025] For example, if the set current warning value is a specific value, and the monitored real-time current exceeds this value, it will be determined that there may be a potential fault or abnormal situation.

[0026] When the monitoring result exceeds the warning value, it will respond quickly. It will generate corresponding warning alarm information to remind relevant personnel to pay attention to possible problems in the medium-voltage line. At the same time, if the situation is serious and meets the fault judgment criteria, fault information will also be generated. Fault information usually includes detailed data waveforms to facilitate further analysis and diagnosis of the fault. At the same time, the corresponding monitoring results will also be attached to provide a strong basis for locating and solving the fault.

[0027] For example, at a certain moment, the voltage in the medium-voltage line suddenly drops sharply. By comparing the warning value, it is determined to be a fault, and fault information containing the voltage waveform and specific monitoring values ​​is generated, so that maintenance personnel can quickly understand the nature and severity of the fault and take effective repair measures to ensure the normal operation of the medium-voltage line.

[0028] The unidirectional communication isolation module is arranged between the medium voltage standardization module and the Internet of Things module, and is used for unidirectional transmission of data from the medium voltage standardization module to the Internet of Things module. Two data transceiver buffers are managed in the unidirectional communication isolation module, one for receiving data from the medium voltage standardization module, and the other for copying data from the medium voltage standardization module and sending it to the Internet of Things module. When copying data, it is necessary to verify the integrity of the data. When verifying the integrity of the data, the public key information of the medium voltage standardization module preset in the unidirectional communication isolation module is first used to verify the certificate signature of the medium voltage standardization module, and the session key is negotiated through the key, and the key is derived from the session key. The derived key is used to verify the integrity of each received data.

[0029] When the IoT module sends data in the data receiving and sending buffer area, it first determines whether the data header contains the acquisition unit port number. If the acquisition unit port number exists, the IoT module modifies the data header to the IoT module communication unit number + the acquisition unit port number when sending the data; if the acquisition unit port number does not exist, the IoT module needs to generate a virtual port number for the data; the IoT uses the MQTT protocol to send data to the cloud.

[0030] When there are other terminals that do not have the Internet of Things function accessing the system, it is necessary to perform standardized conversion of the transmission protocol of other terminals through the standardization unit of the medium voltage standardization module. Other terminals send data to the standardization unit, and then send it to the Internet of Things module through the standardization unit to enable other terminals to have the Internet of Things function. When the data sent by other terminals contains the port number of the collection unit, the Internet of Things module will perform virtualization.

[0031] The medium voltage standardization module also includes an equipment status detection unit, an equipment mechanical characteristics monitoring unit, and an early fault insulation monitoring unit. The equipment status detection unit is used to monitor the elbow head temperature monitoring, cabinet temperature measurement, water immersion, smoke, and partial discharge sensor data in the ring network cabinet / distribution station, and report the set abnormal data through the standardization unit; the equipment mechanical characteristics monitoring unit is used to analyze the current waveform when the switch opening and closing coil is actuated, identify the characteristics of the current waveform, and reflect the conditions of the electromagnet, tripping device, and operating mechanism; the early fault insulation monitoring unit is used to monitor early insulation faults and analyze the causes of the faults.

[0032] like Figure 2 As shown, the working process of the early fault monitoring unit in this embodiment includes: Step S1, collecting instantaneous fault waveforms of the cable lines of the ring main unit, switchgear, cable lines, pole switches, and overhead lines through the collection unit of the medium voltage standardization module.

[0033] Step S2, using the early fault monitoring unit to perform disturbance analysis on the effective value amplitude of the collected current waveform, and judging the single-phase grounding through parameter identification, phase asymmetry method, and zero-sequence power method.

[0034] Step S3, record the number of faults for the cable numbers of the cables with cable fault grounding, analyze the cable fault trend, and conduct regional inspection of single grounding through artificial intelligence algorithm.

[0035] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A medium voltage line online monitoring and fault detection and early warning system based on the Internet of Things, comprising a medium voltage standardization module, an Internet of Things module, and a one-way communication isolation module, characterized in that: The medium voltage standardization module is used for distribution automation services, including distribution data monitoring, fault information monitoring, distribution data reporting, and standardized conversion of other connected devices; the Internet of Things module is used to establish an Internet of Things channel and transmit power data through the Internet of Things channel; The one-way communication isolation module is used to determine the direction of information transmission between the medium voltage standardization module and the Internet of Things module, and transmits information from the medium voltage standardization module to the Internet of Things module in a one-way manner to block the communication; The Internet of Things module includes a communication unit and an expansion unit. The communication unit is used to establish an Internet of Things security channel for encrypted transmission, and the expansion unit is used for extended access to other Internet of Things modules.

2. According to the Internet of Things-based medium voltage line online monitoring and fault detection and early warning system according to claim 1, it is characterized by: The medium voltage standardization module includes a collection unit, a monitoring unit, and a standardization unit. A real-time channel is established between the units of the medium voltage standardization module, and data is sent and received through the real-time channel; the collection unit is used to collect power information with timing information in the circuit, send the power information data to the detection unit through the real-time channel, monitor the power information data through the monitoring unit, and mark the monitoring results in the timing interval of the power information; The standardization unit is used to report the alarm information and fault information, and the fault information includes data waveform and corresponding monitoring results.

3. According to the medium voltage line online monitoring and fault detection and early warning system based on the Internet of Things according to claim 1, it is characterized by: The unidirectional communication isolation module is arranged between the medium voltage standardization module and the Internet of Things module, and is used for unidirectional transmission of data from the medium voltage standardization module to the Internet of Things module. Two data transceiver buffer areas are managed in the unidirectional communication isolation module, one for receiving data from the medium voltage standardization module, and the other for copying data from the medium voltage standardization module and sending it to the Internet of Things module. When copying data, it is necessary to verify the integrity of the data. When verifying the integrity of the data, the public key information of the medium voltage standardization module preset in the unidirectional communication isolation module is first used to verify the certificate signature of the medium voltage standardization module, and a session key is negotiated through a key, and a key is derived from the session key. The derived key is used to verify the integrity of each received data.

4. According to the medium voltage line online monitoring and fault detection and early warning system based on the Internet of Things according to claim 1, it is characterized by: When the Internet of Things module sends data in the data receiving and sending buffer area, it first determines whether there is a collection unit port number in the data header. If there is a collection unit port number, the Internet of Things module modifies the data header to the Internet of Things module communication unit number + collection unit port number when sending the data; if there is no collection unit port number, the Internet of Things module needs to generate a virtual port number for the data; the Internet of Things uses the MQTT protocol to send data to the cloud.

5. According to the medium voltage line online monitoring and fault detection and early warning system based on the Internet of Things according to claim 1, it is characterized by: When there are other terminals that do not have the Internet of Things function accessing the system, it is necessary to perform standardized conversion of the transmission protocol of other terminals through the standardization unit of the medium voltage standardization module. Other terminals send data to the standardization unit, and then send it to the Internet of Things module through the standardization unit to enable other terminals to have the Internet of Things function. When the data sent by other terminals contains the port number of the collection unit, the Internet of Things module will perform virtualization.

6. According to the medium voltage line online monitoring and fault detection and early warning system based on the Internet of Things as claimed in claim 2, it is characterized by: The monitoring unit includes an equipment status detection unit, an equipment mechanical characteristics monitoring unit, and an early fault insulation monitoring unit. The equipment status detection unit is used to monitor the elbow head temperature monitoring, cabinet temperature measurement, water immersion, smoke, and partial discharge sensor data in the ring network cabinet / distribution station, and report the set abnormal data through the standardization unit; the equipment mechanical characteristics monitoring unit is used to analyze the current waveform when the switch opening and closing coil is actuated, identify the characteristics of the current waveform, and reflect the conditions of the electromagnet, the tripping device, and the operating mechanism; the early fault insulation monitoring unit is used to monitor early insulation faults and analyze the causes of the faults.

7. The medium voltage line online monitoring and fault detection and early warning system based on the Internet of Things according to claim 6 is characterized by: The workflow of the early fault monitoring unit includes: Step S1, collecting instantaneous fault waveforms of the cable lines of the ring main unit, the switch, the cable line, the pole switch, and the overhead line through the collection unit of the medium voltage standardization module; Step S2, using an early fault monitoring unit to perform disturbance analysis on the effective value amplitude of the collected current waveform, and judging single-phase grounding through parameter identification, phase asymmetry method, and zero-sequence power method; Step S3, record the number of faults for the cable numbers of the cables with cable fault grounding, analyze the cable fault trend, and conduct regional inspection of single grounding through artificial intelligence algorithm.

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