RFID power grid asset full life cycle management solution

1. Background of the Solution

In recent years, power grid companies have put forward specific management requirements for the full life cycle management of power grid Assets. Although many power grid companies have actively carried out the linkage correspondence between the PMS, PM and AM data of stock assets, and incorporated the linkage results data into the "asset full life cycle management integrated platform" for indicator assessment, there is still a problem of data quality decline due to asset changes. If new management methods are not adopted, the results of the previous asset linkage will not be effectively consolidated. Therefore, it is necessary to apply new technologies and methods to the full life cycle management of assets, realize the timely transmission and feedback of asset change information, and closely link the business and physical objects at all stages of the full life cycle management of assets, forming a horizontal and vertical closed loop of ASSET MANAGEMENT and physical management, and laying a solid foundation for the overall optimization of assets.

2. Objectives of the Solution

This solution aims to achieve the sustainable linkage and consistency of accounts, cards and objects by establishing an equipment physical identification system, integrating the physical flow, information flow and value flow of assets, and realizing information sharing at all stages of asset management. By carrying out tracking management of all stages of the full life cycle of power transmission and transformation equipment of the power grid, it will bring challenges to the asset management model, and also bring opportunities to improve the level of modern management of power transmission and transformation equipment. At present, State Grid Corporation of China and China Southern Power Grid Corporation are actively carrying out research and application of RFID technology in asset and intelligent warehousing management systems.

This solution aims to achieve accurate management of the entire life cycle of equipment, realize dynamic tracking management of equipment through daily operation and maintenance of physical identification data, eliminate the difficulties, blind spots and obstacles of asset management, and realize accurate positioning management of assets and equipment.

III. Overview of the Solution

This solution is tailored by Guangdong Hanglian Technology according to the needs of enterprises. It integrates RFID technology, network technology, computer technology, database technology and wireless communication technology. Combined with Hanglian Technology's rich experience and unique technology, this solution realizes the management of RFID equipment, realizes data exchange with PMS, SAP and other systems, and compares and analyzes the data of accounts, cards and objects, and generates various management reports; at the same time, it realizes the upload and download of business data with RFID handheld terminals, and realizes the daily dynamic management of physical identification.

IV. System Design

1. collection Equipment Selection

RFID technology is applied to power grid asset tracking management. A large number of handheld collection terminals will be used to collect information from on-site physical identification. Since the operation is carried out in an electromagnetic field environment, factors such as the terminal equipment's anti-interference, reading and writing distance, stability, and reliability need to be considered.

(1) Anti-interference factors

Substation equipment will generate power frequency electric fields and power frequency magnetic fields in the operating environment. Power frequency electromagnetic field interference belongs to low-frequency induction field interference. Since the signal inside the handheld terminal does not use the earth as a return path, the electromagnetic protection design of the reader must be considered in the selection and design of the handheld terminal.

(2) Reading and Writing Distance

The physical identification of the power grid is generally installed on the grounding flat iron of the equipment base, and it is at a certain height from the ground to facilitate operators to read and write data. Therefore, the reading and writing distance of the handheld device is of great significance to reducing the walking distance of asset inspectors, reducing work intensity, and improving inspection efficiency.

(3) Battery life of handheld devices

Substations above 220kV occupy a large area, have many devices, and take a long time to install the identification. Therefore, the battery of the handheld device must have a long battery life and can automatically save data after power failure to ensure that the staff can work on site without worries.

2. Physical identification performance

RFID physical identification has the advantages of waterproof, anti-magnetic, high temperature resistance, long service life, large reading distance, data encryption, large storage volume, and storage information can be modified, which are not available in barcodes. It has been widely used in power grid asset tracking management. Therefore, ISO18000-6C metal identification is basically used for asset tracking management. Power grid equipment is often outdoors and in high temperature environments. When designing identification and selecting materials, it is necessary to fully consider factors such as UV protection, read and write distance, and multi-identification reading.

(1) Read and write distance

In the ultra-high frequency electromagnetic environment of the substation, the metal surface shields electromagnetic waves. When the antenna inside the identification is close to the metal surface, the antenna performance will deteriorate significantly. After field application testing, the signal will be greatly attenuated after the label is attached to the surface of the grounded flat iron, and the reading and writing distance will be reduced by 50% to 70%. Therefore, the reading and writing distance should be considered in the design of the label shell, packaging and label posting materials.

(2) Anti-ultraviolet

At present, the packaging shell of ultra-high frequency passive electronic labels generally adopts ABS material. For the revisit of the installed labels, the electronic labels are exposed to the wind and sun in the substation for a long time and are easy to fade. Therefore, consider adding anti-ultraviolet materials when packaging the label shell.

(3) Anti-collision mechanism

There are a large number of substation equipment. In order to speed up the asset inventory and inspection speed, the physical label must consider the anti-collision algorithm when designing, so as to realize the function of batch, fast and accurate reading of multiple labels in each work area.

3. Formulation of labeling specifications

The physical labeling specification is to clearly specify the installation location of the label for each type of equipment, so as to facilitate future installation, identification and reading. The formulation of the labeling specification for power grid equipment should take into account factors such as outdoor equipment, indoor equipment, characteristics of each unit equipment, reading and writing distance and angle between handheld devices and labels, and the general principle must be based on practical applications. At present, the application of RFID technology in substations basically adopts passive metal electronic labels, but it is not practical to install such labels directly on the body of outdoor current transformers, voltage transformers, lightning arresters and other equipment for application. After testing the use of handheld reading and writing devices at home and abroad in substations of various voltage levels, it is impossible to read the identification information more than 2m away. Therefore, the formulation of RFID labeling specifications should take into account the existence of this factor.

4. Physical identification middleware and system integration

At present, the RFID middleware system of power grid companies generally adopts the development model based on SOA architecture, and integrates the PAI interface provided by the RFID reading and writing equipment manufacturer into the middleware system in various ways, such as IP address, port setting, etc., to facilitate the RFID device to read and write identification data, and at the same time, the collected data is combined with the identification business for effective filtering, processing and data transmission, and finally Stored in the middleware database. The middleware can also monitor the RFID equipment and check the operation of the RFID equipment. In addition, the use of RFID middleware can easily realize data interface and data exchange with ERP and other systems.

At present, power grid companies generally use asset life cycle management evaluation decision system to carry out result indicator evaluation. The system mainly extracts data from PMS system and SAP system, but lacks information on on-site physical data. The RFID middleware system and on-site collection equipment are used to collect data on physical identification, and the physical information is fed back to the asset life cycle management evaluation decision system in a timely manner through the interface, realizing a true vertical closed loop of accounts, cards and objects, and providing more accurate asset operation status data for asset life cycle management.

5. Physical identification data storage and data security

At present, the ISO18000-6C standard electronic identification used in the physical asset management of the power grid has the characteristics of mature standards, stable products, wide application, globally unique ID number and simultaneous reading of multiple identifications. It can store 1024b or 2048b of data and has a data reading speed of 40kb/s. When determining the amount of information stored in the physical identification, it is necessary to consider the issue of data exchange between handheld devices and background during on-site operation and maintenance. Although the handheld devices of major suppliers are basically equipped with GPRS function, due to the stability of communication transmission, it is impossible to guarantee that the background data of the middleware system can be obtained smoothly at any time. Therefore, it is necessary to consider carefully when determining the data content of the device information stored in the identification.

6. Data transmission security

In order to prevent data risks, the power grid company adopts strict isolation measures to manage external mobile storage devices or mobile transmission methods. This can prevent the information collected by the handheld device from being uploaded to the middleware system in time, and also prevent the business documents of the middleware system from being easily uploaded to the RFID handheld terminal. At present, data exchange must be achieved through multiple conversions through a secure USB flash drive.

7. Labeling granularity

With the in-depth development of the full life cycle management of power grid companies, the synchronization of PMS system and SAP system PM module equipment has begun, mainly including the synchronization of primary and secondary equipment, but the synchronization work is only for the main equipment, and the auxiliary equipment is not synchronized for the time being. Since the synchronization work has high requirements for the equipment type and certain field maintenance of the PMS system, if the PMS system operator cannot synchronize to the PM module due to lack of business proficiency or lack of responsibility, it will affect the transfer and linkage work with the financial AM module. Therefore, it is recommended to label based on the data of the PMS system. Although this method has the finest granularity and a large workload, the synchronization quality of PMS and PM can be checked during the labeling process, and the linkage quality with AM can be checked. This mode has a positive effect on improving the consistency of accounts (PM), cards (AM), and objects (RFID physical identification).

V. System operation process

1. Identification business after equipment is put into storage

After the equipment is purchased and put into storage, the physical identification can be pasted for the materials that have established linkage relationships with material codes, equipment types and asset classifications. In the middleware system, the manager generates a "physical identification affixing business order" based on the synchronized SAP MM module warehouse entry information, and then writes the material code and equipment type and other information into the physical identification through the RFID Reader, and affixes the physical identification to the corresponding material with double-sided tape. This stage implements the following functions:

(1) After the equipment is successfully put into storage, the identification status of the new equipment is set to "accepted".

(2) For the power grid equipment that is removed for technical modification, maintenance or change, the identification status is set to "dismantled pending".

2. Material direct delivery site identification business

Most power grid equipment is directly delivered to the construction site by the manufacturer. The staff issues a "physical identification affixing task order" in the RFID middleware system, notifying the on-site management personnel to download the task order in time through the RFID handheld terminal, and to accept and affix the identification to the on-site materials and equipment.

This stage realizes the following functions:

(1) It can check and accept the power grid equipment delivered directly to the site. The system will prompt or process in the following situations:

If the on-site equipment is inconsistent with the list information in the "Physical Identification Pasting Task Sheet", the system will issue an alarm prompt and require the on-site personnel to check with the warehouse manager.

(2) After the physical identification is installed, the identification status will be automatically updated to "Under Construction".

3. After the completion and commissioning of the identification information improvement business

After the infrastructure project is completed and put into operation, it is necessary to enter the relevant information and dispatch name of the equipment into the PMS system within the specified time. When the RFID middleware system collects information from the PMS system, the staff will issue an "Equipment Commissioning Identification Information Maintenance Sheet" to notify the staff to download the task sheet on the RFID handheld terminal in time and improve or change the information in the pasted identification on site.

This stage achieves the following functions:

(1) It can improve the identification information of on-site equipment, such as the equipment dispatch name. The system will prompt or process in the following situations:

If the on-site equipment is inconsistent with the list information in the "Physical Identification Pasting Task Sheet", the system will issue an alarm prompt and require on-site personnel to check with PMS maintenance personnel.

(2) After the identification information is maintained, the identification status will automatically change to "operation".

4. Technical transformation and overhaul identification management business

When the substation is undergoing technical transformation or overhaul, some equipment will be added, so corresponding identification management is required. The staff will create an "Identification Installation and Information Maintenance Task Sheet" in the RFID middleware system, and then download the task sheet through the RFID handheld terminal. For the newly added equipment in the technical transformation, the identification needs to be pasted; for the dismantled equipment, the original electronic identification needs to be removed and reinstalled on the dismantled equipment body for future reuse or scrap tracking and processing; for the retired equipment, the equipment status information in the identification needs to be updated.

This stage can achieve the following functions:

(1) For the newly installed equipment, the identification is pasted.

(2) For retired equipment, the RFID handheld terminal changes the identification status to "retired".

(3) For dismantled equipment, the RFID handheld terminal changes the identification status to "pending dismantling".

(4) For equipment that has undergone major repairs, the RFID handheld terminal can update the relevant equipment information in the identification.

(5) For equipment that has undergone routine maintenance, maintenance information can be entered in the RFID handheld terminal and uploaded to the RFID middleware system.

5. Services implemented by RFID handheld terminals

The RFID handheld terminal system and the RFID middleware system conduct business docking, mainly downloading tasks such as asset addition, asset scrapping, and asset inventory uploaded by the RFID middleware to the RFID handheld terminal, and uploading the results after completing the collection work. The RFID handheld terminal can also complete the daily inspection business of equipment identification independently.

5.1 Daily operation and maintenance business of identification

The power grid equipment operation team regularly performs daily identification information scanning tasks, and at the same time verifies whether the identification information content is consistent with the on-site equipment information.

The following functions can be achieved at this stage:

(1) It can automatically identify the equipment being inspected and compare it with the equipment list in the RFID inspection task list. Only the equipment in the task list is allowed to be read. The system can display the attribute parameter information and historical status information of the current equipment.

(2) After the equipment status scan is completed, the scanned equipment changes the power grid equipment status to "verified" through the RFID reader. For equipment with problems, the equipment status will be changed to "pending verification".

5.2 Asset inventory business

The previous "paper inventory mode" has problems such as repeated data entry, missed equipment inspection and re-inspection, process out of control, high labor intensity, and formal inventory. Using identification inventory can achieve full monitoring and management of the inventory process, avoid problems caused by manual inventory, shorten asset inventory time, and improve inventory quality.

Download the inventory task through the RFID middleware system, and the RFID handheld terminal can start the inventory after downloading the inventory task list, and record the problems found during the inventory process in the RFID handheld terminal.