Distribution cable multi-state micro-power-consumption integrated sensing method, system and device

Abstract

The invention discloses a distribution cable multi-state micro-power-consumption integrated sensing method, system and device. The method comprises the following steps: acquiring a distribution cable multi-state sensor and related materials of a distribution cable; according to the materials, a low-power-consumption and miniaturized integration scheme of multiplexing a multi-sensing parameter module of the sensor and sharing a signal acquisition, processing and protection circuit by a plurality of sensing units is determined; designing a signal acquisition, processing and protection circuit shared by a plurality of sensing units; establishing micro-power consumption long-distance wireless communication; the integrated design of the micro-power-consumption multi-state sensing device is realized; based on a chip energy consumption management and power saving technology, low-power-consumption hardware and software are realized; based on a micro-power-consumption communication technology, micro-power-consumption long-distance wireless communication is realized; sharing of sensing device body data and power grid ring main unit DTU data is realized; by adopting the micro electro mechanical system method, the purposes of real-time monitoring and effective control of various types of information of the power cable are achieved, and guarantee is provided for solving the practical problem of operation and maintenance of a distribution network.

Description

Technical Field

[0001] The present invention relates to the technical fields of power systems, power electronics technology, signal systems, and spread spectrum communication theory, and particularly relates to a multi-state micro-power integrated sensing method, system, and device for distribution cables based on wireless low-power sensors and low-power remote wireless communication technology. Background Art

[0002] The idea of on-line monitoring originated in the 1950s. Around 1970, many countries successively began the development of on-line monitoring of power systems. In 2003, Sumitomo Corporation of Japan began to research and develop an on-line monitoring system for power cables. This monitoring system not only includes traditional monitoring methods such as circulating current and well water level, but also integrates monitoring methods for distributed temperature sensing (DTS) and dynamic cable rating (DCR). In addition, partial discharge monitoring was subsequently added to the system. In the same year, LS Cable & System of South Korea (formerly LG Industrial Systems) also followed suit and completed the development of the above monitoring system. Some European and American countries represented by NKT (Nordiske KabelogTraadfabriker) of Germany and CYME (CYME International Inc.) of Canada have also mastered the technology of integrating DTS and DCR in cable monitoring systems.

[0003] Due to the limitation of the technical development level in the last century, the development of cable on-line monitoring in China started relatively late. It was not until around 1970 that domestic high-level experts began to invest in the research of on-line monitoring systems for power cables.

[0004] After more than 20 years of continuous development, at present, the State Grid Corporation of China mainly has on-line monitoring devices such as ground current monitoring, video monitoring, water level monitoring, optical fiber temperature measurement, gas monitoring, and fire monitoring. Experience in partial discharge monitoring has only been accumulated on a small number of lines.

[0005] When existing data-driven technologies are studied in power equipment, there are drawbacks that tend to be realized only by combining real-time big data. On the one hand, this brings huge challenges to the energy consumption of on-site monitoring devices when sensing information and transmitting data, and is not suitable for the actual scenarios of distribution cable and channel state monitoring; on the other hand, too much data also leads to the need to spend a large amount of computing power to screen useless data when deducing the device state, and will increase the complexity of the data body, making the influencing factors of the insulation structure of distribution cables more complex, and the prediction time also becomes longer, which is not suitable for on-line operation and maintenance. Summary of the Invention

[0006] The main object of the present invention is to provide a multi-state micro-power integrated sensing method, system and device for distribution cables, aiming to solve existing technical problems.

[0007] To achieve the above object, the present invention provides a multi-state micro-power integrated sensing method for distribution cables, characterized by including:

[0008] S1. Obtain relevant materials of the multi-state sensor of the distribution cable and the distribution cable itself;

[0009] S2. Determine a low-power and miniaturized integration scheme for multiplexing of multi-sensing parameter modules, shared signal acquisition, processing, and protection circuits of multiple sensing units according to the above materials;

[0010] S3. Design a signal acquisition, processing, and protection circuit shared by multiple sensing units;

[0011] S4. Establish micro-power long-distance wireless communication;

[0012] S5. Implement an integrated design of a micro-power multi-state sensing device;

[0013] S6. Based on chip energy consumption management and power-saving technologies, implement low-power hardware and software;

[0014] S7. Based on micro-power communication technologies, implement micro-power long-distance wireless communication;

[0015] S8. Realize the sharing of the data of the sensing device body and the data of the grid ring main cabinet DTU.

[0016] Further, the relevant materials of the multi-state sensor include data on the sensor installation method, type, volume, power consumption, reliability, accuracy, stability, and operating conditions.

[0017] Further, the relevant materials of the distribution cable include data on the measurement ranges of cable partial discharge, vibration, external force impact, temperature and humidity, and water immersion.

[0018] Further, S2 includes adopting a multiplexing technology for multi-sensing parameter modules, designing a signal acquisition, processing, and protection circuit shared by multiple sensing units, simplifying the sensor structure, determining specific requirements for the implementation of multi-parameter fusion sensing technology from three dimensions of the operating environment, sensor performance, and application status, including sensor range, volume, power consumption, vibration resistance, accuracy, and operating temperature, and determining the selection principle of multi-parameter sensing elements.

[0019] Further, the micro-power multi-state sensing device is used to drive a variety of sensors to collect distribution cable data, and form a LoRa wireless sensor network with a gateway placed in a manhole to achieve coverage monitoring along the cable.

[0020] An integrated multi - state micro - power consumption sensing device for distribution cables, comprising:

[0021] A sensor module, which is used to monitor and collect cable status and channel information, and generate an output signal for analysis and processing by the processor module;

[0022] A processor module, which is used to send data to a LoRa / 5G gateway through a LoRa communication module;

[0023] A communication module, which is used to form a wireless sensor network for coverage monitoring along the cable;

[0024] A storage module, which is used to store the monitored cable status and channel information.

[0025] Furthermore, the sensor module is composed of multiple patch sensing units to form a sensing array.

[0026] An integrated multi - state micro - power consumption sensing system for distribution cables, comprising:

[0027] The sensing layer: It is used to regularly collect distribution cable status and environmental data such as the surface temperature of joints and terminal cables, abnormal vibration, partial discharge, ambient temperature and humidity, water immersion, etc., and send them to the gateway through the LoRaWan protocol;

[0028] The network layer: It is used to relieve the concurrent conflicts caused by node data reporting, and at the same time convert LoRa wireless signal data into 5G communication data packets and upload them to the cloud platform;

[0029] The application layer: It is used to obtain the data uploaded by the gateway in real - time and store the monitored data in the local database.

[0030] The beneficial effects of the present invention are as follows:

[0031] (1) The multi - state sensing module of the present invention adopts an integrated design of transient earth voltage, ultrasonic, surface temperature, and ambient temperature and humidity sensors, which is suitable for the status monitoring of switchgear - type and cable - type equipment in the main and distribution networks within the power system, and has a wider applicable scenario.

[0032] (2) The present invention adopts a magnetic - adsorption and cable - tie bundling installation design, which is directly fixed to the cable joint through cable ties, making the installation more convenient.

[0033] (3) The present invention adopts an internal disposable battery power supply method and a low - power consumption sleep - wake working mode, which greatly reduces the power consumption of the system.

[0034] (4) The integrated multi - state micro - power consumption sensing device developed by the present invention solves the problems of poor adaptability and restrictive problems such as power supply and communication in traditional cable monitoring technologies, and is suitable for the status early warning of distribution cable lines and channels, with broad prospects for the application and transformation of the results.

[0035] (5) The multi-state micro-power integrated sensing device developed by the present invention can significantly improve the operation reliability of the distribution cable system and greatly reduce the occurrence of tripping accidents of cables, intermediate joints and terminals caused by non-standard laying, installation, operation and maintenance.

[0036] (6) The present invention can not only provide the basis of sensing data of cable status for the cable operation and maintenance and status evaluation of the medium-voltage distribution network, but also provide a reference method for the development of multi-parameter integration of other distributed distribution devices.

[0037] (7) The present invention provides a sensing means for the distribution network cable for subsequent establishment of a wireless monitoring network along the distribution cable laying path, construction of a distribution cable and channel data body integrating multi-source data, enabling the virtual digital model to predict the operation status of the distribution cable and approaching the operation status of the distribution cable entity in real time.

[0038] (8) The device of the present invention has high sensitivity for temperature monitoring and partial discharge monitoring of distribution cables, low operating power, and a long maximum wireless communication distance.

[0039] (9) The device of the present invention adopts a closed-loop structure, and the output digital signal is fed back to the sensitive unit through electrostatic force, pushing the quantization noise to high frequency, making the sensitive unit stable in the middle of the two plates, and improving the system linearity and signal bandwidth.

[0040] (10) The present invention replaces the operational amplifier in the switched-capacitor integrator with an inverter, removes the offset voltage therein through auto-zeroing, and makes the inverter work in the sub-threshold region by adjusting the supply voltage, thereby greatly reducing the power consumption of the integrator. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic flow chart of the multi-state micro-power integrated sensing method for the distribution cable of the present invention;

[0042] Figure 2 It is a schematic structural diagram of the partial discharge sensor device of the present invention;

[0043] Figure 3 It is a schematic hardware structure diagram of the LoRa / 5G gateway of the present invention;

[0044] Figure 4 It is a schematic composition principle diagram of the multi-state sensing device of the present invention;

[0045] Figure 5 It is a schematic diagram of the overall system framework of the present invention;

[0046] Figure 6 It is a frequency signal diagram of the spread spectrum modulation processing of the present invention;

[0047] Figure 7Frequency signal diagram for despreading and demodulation processing of the present invention;

[0048] Figure 8 Schematic diagram of the anti-interference ability of the spread spectrum system of the present invention;

[0049] Figure 9 Another schematic diagram of the anti-interference ability of the spread spectrum system of the present invention;

[0050] Figure 10 Schematic diagram of the LoRa terminal type of the present invention. Detailed implementation manners

[0051] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0052] Although wireless low-power sensor technology has been applied in the insulation monitoring of distribution network switch cabinets, the long length of distribution cables and narrow channels pose higher requirements for communication distance and power consumption management, which is not only reflected in the external transmission of data of the sensing unit, but also in how to avoid missing the abnormal state of the cable. Therefore, it is crucial to implement wireless low-power technology suitable for multi-state sensing of distribution cables.

[0053] In order to meet the development requirements of the live maintenance work of cables, based on intelligent technologies such as the Internet of Things and intelligent sensors, the monitoring of the operating state of equipment under live conditions is realized. Through intelligent sensor monitoring technologies such as transient earth voltage (TEV), ultrasonic (AE & Ultrasonic), ultra-high frequency (UHF), surface temperature of the equipment body, vibration, and ambient temperature and humidity, the intelligent perception of the cable operating state is realized.

[0054] Please refer to Figures 1-10, the objective of the present invention is to propose an integrated perception method for cable surface temperature, abnormal vibration, partial discharge, ambient temperature and humidity, water immersion, etc. by researching compact multi-state perception sensor technology applicable to distribution cables; based on chip energy consumption management and power saving technology and micro-power communication technology, design a hardware power consumption management scheme for multi-state perception devices, construct low-power hardware, software powered by lithium batteries, and a micro-power long-distance wireless communication program; research a micro-power measurement scheme integrating temperature, humidity, vibration and partial discharge, develop a multi-state perception device for cable surface temperature, ambient temperature and humidity, abnormal vibration, partial discharge and water immersion, etc., and realize data sharing with the ring main unit DTU (Data Transfer Unit).

[0055] (1) By adopting the micro-electro-mechanical system (MEMS) method, the present invention constructs a micro-power multi-state perception device for monitoring the temperature, humidity, vibration and partial discharge of distribution cables, realizes the purpose of real-time monitoring and effective control of various types of information of power cables, and provides a guarantee for solving practical problems in distribution network operation and maintenance.

[0056] (2) Based on partial discharge, external force damage and temperature multi-parameter sensing units, and combined with basic theories such as power systems, power electronics technology, signals and systems, etc., the present invention conducts research on micro-power multi-state perception technology for distribution cables, constructs a multi-state perception device for temperature, humidity, vibration and partial discharge that meets the requirements, and provides a data perception device for predicting the operation status of distribution cables and channels.

[0057] (3) The present invention solves the problem of the lack of means for perceiving the status of distribution network cables and improves the ability to discover and dispose of hidden dangers inside distribution cables.

[0058] Specifically, based on MEMS sensors and LoRa, the key information reflecting the operation status of distribution cables - temperature, humidity, vibration and partial discharge monitoring - is integrated into one sensor, realizing the perception and edge computing of cable temperature, abnormal vibration, partial discharge and ambient humidity.

[0059] The multi-state micro-power integrated perception method, system and device for distribution cables are designed as follows:

[0060] The perception method includes: collecting and sorting out information such as the installation method, type, volume, power consumption, reliability, accuracy, stability, operating conditions, etc. of multi-state sensors for distribution cables;

[0061] S2. Collecting and sorting out information such as the measurement ranges of partial discharge, vibration, external force impact, temperature and humidity, water immersion, etc. of distribution cables;

[0062] S3. Determining a low-power and miniaturized integration scheme for multi-perception parameter module multiplexing of sensors, shared signal acquisition, processing, and protection circuits for multi-perception units;

[0063] S4. Design a signal acquisition, processing, and protection circuit shared by multiple sensing units;

[0064] S5. Implement a micro-power long-distance wireless communication design;

[0065] S6. Implement an integrated design of a micro-power multi-state sensing device;

[0066] S7. Based on chip energy consumption management and power-saving technologies, implement low-power hardware and software;

[0067] S8. Based on micro-power communication technology, implement micro-power long-distance wireless communication;

[0068] S9. Realize the data sharing between the data of the sensing device body and the DTU data of the grid ring main unit cabinet.

[0069] Specifically, (1) Sensing method of the micro-power multi-state sensing device

[0070] ① First, investigate the operating conditions of the multi-state sensors for distribution cables, including installation information such as different laying methods, types, structural characteristics of distribution cables, and sensor installation methods, as well as information such as temperature, partial discharge, vibration, external force impact, and environmental humidity. Analyze these data and information to determine the environmental constraints for sensor applications.

[0071] ② Then, collect the actual on-site usage data of sensors such as cable partial discharge, external force, temperature, and water immersion, and analyze the key factors affecting the operating accuracy, volume, power consumption, and reliability of the sensors, providing a basis for sensor selection.

[0072] ③ Finally, study and compare the performance parameters such as measurement range, accuracy, and stability of partial discharge, vibration, temperature, and water immersion with different sensing principles, and determine the performance constraints for sensor applications.

[0073] Based on the environmental constraints, performance constraints, and selection principles of sensor applications, determine a low-power and miniaturized integration scheme for the multi-sensing parameter module multiplexing of sensors and the signal acquisition, processing, and protection circuit shared by multiple sensing units.

[0074] (1) Integrated design of the micro-power multi-state sensing device

[0075] ① First, implement the low-power and miniaturized design of the multi-parameter sensor. Adopt the multi-sensing parameter module multiplexing technology to design a signal acquisition, processing, and protection circuit shared by multiple sensing units, and simplify the structure of the sensor.

[0076] Determine the specific requirements for the implementation of the multi-parameter fusion sensing technology from three dimensions: the operating environment, sensor performance, and application status, including sensor range, volume, power consumption, anti-vibration, accuracy, operating temperature, etc., and determine the selection principles for multi-parameter sensing elements.

[0077] Compared with other sensors, MEMS sensors have the characteristics of small size, light weight, low cost, low power consumption, high reliability, suitability for mass production, easy integration, etc., and can realize the miniaturization of sensing elements. The selection of MEMS sensors mainly refers to factors such as the working temperature range, accuracy requirements, electrical characteristics, working power supply, power consumption, measurement response time, vibration and shock characteristics, long-term stability error, repeatability, measurement range, resolution, linearity, etc. The comparison of the characteristics of MEMS sensors with different principles is shown in the following table.

[0078] Table 1 Characteristics of MEMS Sensors with Different Principles

[0079]

[0080]

[0081] All sensors, MCU (Microcontroller Unit) and other devices select low-voltage components and have a shutdown function, which can realize start-up-sleep control and meet the low-power requirements.

[0082] Since the current pulses propagate in different directions, if the partial discharge does not occur at the center position of the terminal, the attenuation and loss of the pulses on different paths will be different, resulting in a decrease in the detection accuracy. Therefore, this device uses multiple patch sensing units to form a sensing array to make up for the deficiency of the capacitive sensor in directional sensitivity, as Figure 2 shown. Specifically, a plurality of sensing patches 1 are provided inside the housing 2, and the housing 2 is connected to the BNC connector 3 through a signal cable 4.

[0083] ② Then, realize the design of micro-power long-distance wireless communication, such as Figure 3 .

[0084] ③ Finally, realize the design of a micro-power multi-state sensing device. The multi-state sensing device is responsible for driving a variety of sensors to collect distribution cable data and forming a LoRa wireless sensor network with the gateway placed in the manhole to realize the coverage monitoring along the cable. When designing the hardware circuit of the terminal node, the functions of each part are modularized and interconnected respectively using standard buses such as SPI and I2C, which simplifies the system structure and the hardware circuit design and is convenient for later maintenance and upgrade. The hardware of the terminal node consists of 5 functional modules: sensor, CPU, LoRa communication, power supply, and storage management, as Figure 4 shown.

[0085] Multi - state sensing devices are evenly distributed as terminal points on the cables of the channel to be measured. Its sensor module is responsible for monitoring and collecting cable status and channel information, and generating output signals for the processor to analyze and process; the processor module sends the data to the LoRa / 5G gateway through the LoRa communication module.

[0086] (2) System Design of Micro - power Multi - state Sensing Device

[0087] ① First, based on chip energy consumption management and power - saving technology, low - power hardware and software powered by lithium batteries are used. The multi - state sensing device for distribution cables and the data processing unit are connected by wire to form an integrated physical sensor unit.

[0088] ② Then, based on micro - power communication technology, a micro - power long - distance wireless communication program is adopted. The data processing unit realizes high - speed acquisition and lightweight processing of status data, and the sensors and communication nodes form a wireless network to realize long - distance wireless transmission of status data.

[0089] ③ Finally, the data sharing between the sensing device body data and the DTU data of the grid ring - main unit is realized, and the multi - state sensing data is transmitted to the backend server for subsequent multi - parameter information fusion and cable operation status prediction.

[0090] The compact multi - state sensing system of the entire distribution cable is functionally divided into three levels, as Figure 5 .

[0091] The first level is the sensing layer: The terminal nodes integrating the compact multi - state sensors of the distribution cable and the LoRa wireless communication module regularly collect the surface temperature of joints and terminal cables, abnormal vibration, partial discharge, ambient temperature and humidity, water immersion and other distribution cable status and environmental data, and send them to the gateway through the LoRaWan protocol.

[0092] The second level is the network layer: The LoRa / 5G gateway, as the hub between the sensor network and the external network, has the ability of multi - channel reception and demodulation, which can relieve the concurrent conflicts caused by node data reporting. At the same time, it converts the LoRa wireless signal data into 5G communication data packets and uploads them to the cloud platform. The LoRa / 5G gateway is arranged at the cable terminal.

[0093] The third level is the application layer: The background server uses the API interface of the cloud platform to obtain the data uploaded by the gateway in real - time, stores the monitoring data in the local database; it is also responsible for the final processing of the data reported by the terminal nodes, provides an interactive interface for users, and realizes real - time data display, dynamic curve drawing of data and node status query.

[0094] It should be noted that if there are directional indications in the embodiments of the present invention, such as up, down, left, right, front, back..., the directional indications are only used to explain the relative positional relationship and movement conditions between components in a specific posture as shown in the drawings. If the specific posture changes, the directional indications will also change accordingly.

[0095] In addition, if there are descriptions such as "first" and "second" in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and should not be construed as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and / or" appearing throughout the text includes three parallel scenarios. Taking "A and / or B" as an example, it includes scenario A, or scenario B, or the scenario where A and B are satisfied simultaneously. In addition, "a plurality of" means two or more. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist.

[0096] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. An integrated sensing method for multi-state and micro-power consumption of distribution cables, characterized in that , including: S1. Obtain relevant materials of the distribution cable multi-state sensor and the distribution cable itself; S2. Determine a low-power and miniaturized integration solution for the multiplexing of multi-sensing parameter modules, the shared signal acquisition, processing, and protection circuits of multi-sensing units based on the above materials; S3. Design signal acquisition, processing, and protection circuits shared by multiple sensing units; S4. Establish micro-power long-distance wireless communication; S5. Realize the integrated design of the micro-power multi-state sensing device; S6. Based on chip energy consumption management and power-saving technologies, realize low-power hardware and software; S7. Based on micro-power communication technologies, realize micro-power long-distance wireless communication; S8. Realize the data sharing between the sensing device body data and the DTU data of the grid ring main unit.

2. The integrated perception method for multi-state and micro-power consumption of a distribution cable according to claim 1, wherein: The relevant materials of the multi-state sensor include data on the sensor installation method, type, volume, power consumption, reliability, accuracy, stability, and operating conditions.

3. The integrated perception method for multi-state and micro-power consumption of a distribution cable according to claim 1, characterized in that: The relevant materials of the distribution cable include data on the measurement ranges of cable partial discharge, vibration, external force impact, temperature and humidity, and water immersion.

4. The integrated sensing method for multi-state and micro-power consumption of a distribution cable according to claim 1, wherein: S2 includes adopting the multiplexing technology of multi-sensing parameter modules, designing signal acquisition, processing, and protection circuits shared by multiple sensing units, simplifying the sensor structure, and determining the specific requirements for the implementation of multi-parameter fusion sensing technology from three dimensions: the operating environment, sensor performance, and application status, including sensor range, volume, power consumption, vibration resistance, accuracy, and operating temperature, and determining the selection principle of multi-parameter sensing elements.

5. The integrated sensing method for multi-state and micro-power consumption of a distribution cable according to claim 1, wherein: The micro-power multi-state sensing device is used to drive various sensors to collect distribution cable data and form a LoRa wireless sensor network with the gateway placed in the manhole to achieve coverage monitoring along the cable.

6. An integrated sensing device for multi-state and micro-power consumption of distribution cables, characterized in that: Including, A sensor module, which is used to monitor and collect cable status and channel information and generate an output signal for analysis and processing by the processor module; A processor module, which is used to send data to the LoRa / 5G gateway through the LoRa communication module; A communication module, which is used to form a wireless sensor network for coverage monitoring along the cable; A storage module, which is used to store the monitored cable status and channel information.

7. An integrated perception device for multi-state and micro-power consumption of a distribution cable, characterized in that: The sensor module adopts multiple patch sensing units to form a sensing array.

8. An integrated perception system for multi-state and micro-power consumption of distribution cables, characterized in that: Including, The sensing layer: It is used to regularly collect distribution cable status and environmental data such as the surface temperature of joints and terminal cables, abnormal vibration, partial discharge, environmental temperature and humidity, and water immersion, and send them to the gateway through the LoRaWan protocol; The network layer: It is used to alleviate the concurrent conflicts caused by node data reporting, and at the same time convert the LoRa wireless signal data into 5G communication data packets and upload them to the cloud platform; The application layer: It is used to obtain the data uploaded by the gateway in real time and store the monitoring data in the local database.

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