Intelligent substation auxiliary equipment comprehensive monitoring system solution

Application background

Power system is a power production and consumption system composed of power generation, transmission, transformation, distribution and power consumption. As the core link of the power grid, the substation is responsible for the high and low voltage transformation and power supply tasks in the region, and safe operation is particularly important.

With the continuous progress of substation automation technology, the efficiency reform of power grid companies, the unattended mode has been comprehensively promoted in the substation operation and maintenance department. The "four remotes" (remote control, remote signaling, remote measurement and remote regulation) function of the substation integrated automation system is mainly aimed at the production and operation conditions, and cannot guarantee the operation environment in the station, so it cannot meet the needs of the substation to be completely unmanned. As a supporting construction, the substation auxiliary equipment monitoring system provides video monitoring, security protection, environmental monitoring, auxiliary control and other functions, making the operation of the substation more safe and reliable, and has become an important support part of the substation information construction.

After more than ten years of construction, the substation auxiliary equipment monitoring system has gradually explored a set of construction mode suitable for the operation and maintenance management of unmanned substations. So far, there are mainly three stages:

1、 Intelligent substation stage (2010-2014)

The integration of all relevant auxiliary systems has been completed and attempted with the production system, which provides an important guarantee for the substation to reduce operation and maintenance costs, optimize resource allocation and improve operation indicators.

2、 Intelligent patrol substation stage (2014-2018)

Remote inspection of equipment appearance, instrument and status indication is realized, such as oil leakage and corrosion of equipment, oil temperature and oil level reading, switch switch status, etc. Some inspection items realize intelligent analysis.

3、 Smart substation stage (2018 present)

Accelerate the realization of remote inspection and automatic inspection, and promote the joint automatic inspection of high-definition video and intelligent inspection robot. Realize the deep perception of the operation status of power grid equipment, improve the intelligent information level of equipment operation inspection, and improve the operation inspection efficiency and equipment operation reliability.

Smart substation technology is a continuous innovation and reform based on smart substation technology. It integrates new technologies such as artificial intelligence and the Internet of Things, comprehensively collects the environmental quantity, physical quantity, state quantity and electrical quantity of the substation, fully applies modern information technology, and reflects the safety, advanced and practical, front-line oriented, and efficient operation and inspection. The pilot construction of smart substation with comprehensive state awareness, information interconnection and sharing, human-computer friendly interaction, highly intelligent equipment diagnosis, and greatly improved operation and inspection efficiency will effectively support the promotion of the "power Internet of Things" of the grid company.

Since the end of 2019, State Grid and Southern Power Grid have issued a number of policy documents for smart substations. In December 2019 and January 2020 respectively, the State Grid Equipment Department issued the Notice of the State Grid Equipment Department on Carrying out the Construction of the Remote Intelligent Patrol System for UHV Converter Stations (Equipment DC [2019] No. 103) and the Notice of the State Grid Equipment Department on Issuing the Construction Scheme of the Remote Intelligent Patrol System for UHV AC Substation (Equipment Substation Power [2020] No. 3), Effectively guide the construction of remote intelligent patrol system for UHV converter station/AC substation. In the aspect of Southern Power Grid, the Promotion and Application Manual of the New Generation of Intelligent Substation (Trial) - Intelligent Patrol Volume, the Promotion and Application Manual of the New Generation of Intelligent Substation (Trial) - Intelligent Operation Volume, and the Promotion and Application Manual of the New Generation of Intelligent Substation (Trial) - Intelligent Security Volume have also been issued, providing a direction for subsequent business applications and intelligent analysis in the station.

The design and development of auxiliary equipment monitoring system of Dingxin smart substation originated from the first batch of smart substation construction pilot project in 2010 - Zhejiang Jinhua 500kV Zhiyan substation. In the past ten years, Dingxin Smart has actively participated in the preparation of standards and specifications of the grid company, interpreted the policy documents of the grid company in detail, and closely followed the pilot projects of grid companies at all levels. It is an important solution provider of the grid company's substation intelligent auxiliary monitoring system. We are willing to contribute to a strong smart grid with the spirit of craftsmanship, integrity and innovation.

Application architecture

In combination with the actual needs and system architecture planning of smart substations, the comprehensive monitoring system for auxiliary equipment of smart substations needs to integrate multiple management subsystems, provide a unified platform for collaboration and cooperation for multiple "information islands" based on front-end sensing equipment, and establish a set of highly integrated and intelligent management mechanism to meet the system requirements of unified configuration management, data sharing, functional linkage and business optimization.

The intelligent substation auxiliary equipment comprehensive monitoring system is a comprehensive embodiment of the overall application architecture of intelligent substation operation and maintenance services. It aims to provide security for equipment patrol monitoring, equipment status review, on-site environmental management, inbound personnel management and other applications with video as the core technology of the Internet of Things, provide one-stop intelligent substation operation and maintenance services for users, and help "safe production, quality and efficiency".

Cheng patrols

The operation and maintenance personnel conduct on-site inspection and make simple qualitative judgment on the sense of the operating equipment, which is mainly realized through the senses of seeing, smelling, listening, measuring and checking. The site patrol is greatly affected by the physical and psychological quality, sense of responsibility, external working environment, work experience, and technical skills of the personnel, so there is a possibility of missing patrol and defect detection.

The equipment remote patrol application mainly configures the patrol type according to the substation patrol regulations, and carries out manual and intelligent patrol on the electrical equipment in the station according to the plan in combination with the video capability. Manual patrol refers to the manual patrol of the patrol points under the electrical equipment in sequence by means of manual capture, video recording, patrol record, etc. Intelligent patrol refers to a set of processes that automatically capture pictures, intelligently analyze those equipped with intelligent analysis items, and finally manually confirm.

On line temperature measurement of equipment

The infrared online temperature measurement mode can realize the functions of full screen temperature measurement, automatic inspection, abnormal alarm, temperature analysis, expert diagnosis, etc., and improve the operator's ability to identify and predict equipment defects. After the temperature warning, the operation and maintenance personnel can take corresponding measures in time to reduce the load or change the system operation mode to ensure the safety of equipment operation.

The use of infrared online temperature measurement not only ensures the healthy operation of equipment, but also provides a scientific basis for predictive maintenance of equipment, improves work efficiency, reduces power outage time, thus increasing equipment availability, and provides technical support for power grid security and even social stability. At the same time, it reduces the number of on-site inspections by personnel, improves the work efficiency of operation and maintenance personnel, and adapts to the development needs of intelligent substations.

Equipment online auscultation

Sound is a kind of mechanical wave that radiates energy from vibration to sound transmission medium. It is the same as the signal analysis method caused by vibration and deformation. Sound signal contains a lot of vibration information, and is an important indicator for analyzing equipment operation status. When the equipment is in normal operation, when the mutual motion state between the body and the firmware, between the parts, and between the parts themselves changes, the equipment will make a sound, and the sound will also change when the operation state changes.

The detection and propagation of sound signal shall not be interfered by electric and magnetic fields, and the monitoring process shall not affect the normal operation of equipment. At present, the analyzed audio mainly uses the audible sound with the frequency of 20Hz-20KHz, which can theoretically analyze the fault type of the operating equipment and the physical characteristics of the acoustic signal.

Equipment fault diagnosis technology based on acoustic characteristics is a new detection method, which is very similar to the principle of expert diagnosis. Big data acquisition and artificial neural network are used to digitally manage the characteristics of sound signals, gather various information databases of sound characteristics, and combine expert diagnosis technology to analyze the sound of equipment and compare it with the defect database, making it feasible to use the sound for the diagnosis of equipment.

Visual production review

The platform can be divided into remote control operation video review and equipment trip video review through communication server, SCADA transaction server (dispatching automation system) and sequence control host (one key sequence control system).

Equipment remote control video recheck

The switching operation is to switch the state of the bay from running to standby, or from standby to running. At present, remote control operation has replaced local operation.

Taking a line bay at 220kV site as an example, it mainly includes live equipment such as bus side disconnector (commonly known as bus knife switch, opening positive bus knife switch, auxiliary bus knife switch), circuit breaker (commonly known as switch), line side disconnector (commonly known as line knife switch).

Video review of equipment tripping

When a line fails, the switch trips from closing position to opening position, and the fault information is sent to the production system (EMS system/SCADA system) through the event message. The system will automatically pop up all image information of the fault equipment and the industrial environment information of the area where the equipment is located, which is convenient for comprehensive analysis and grasp of the fault phenomenon.

After the equipment trips and changes its position, in addition to manual video verification, intelligent analysis can also be used for auxiliary confirmation.

One key sequential control assistance

Compared with the traditional manual switching operation, the one button sequential control operation can save operator time, save traffic costs, and reduce traffic risks. At present, power grid companies around the country are promoting it. The one key sequence control service takes the output image intelligent analysis result signal as the auxiliary criterion of one key sequence control operation, which is superior to visual production review based on visual production review.

The sequence control host sends the remote control preset signaling of the knife switch to the management server through the positive isolation device. The management server automatically calls the corresponding monitoring point of the knife switch and links the preset position. When the management server receives the remote signal displacement signal of the knife switch, the snapshot is pushed to the intelligent analysis equipment to start the image intelligent analysis. The management server outputs the knife switch opening and closing status signal to the sequence control host through the communication server in the form of soft message. When the status of the double position remote signaling displacement signal is consistent with that of the image analysis result signal, the "double confirmation" of the opening and closing positions is completed, and the one key sequential control process is automatically executed downward.

When the one key sequential control is executed in the center, the dispatching automation system sends the sequence control preset signaling to the management server through the forward isolation device and the SCADA event server in Zone III. The management server automatically calls the corresponding monitoring point of the knife switch and linkage preset position. When the management server receives the knife switch remote signal displacement signal, the snapshot is pushed to the intelligent analysis equipment to start the image intelligent analysis, The management server outputs the switch opening and closing status signal to the SCADA event server through the communication server in the form of soft message, and the SCADA event server outputs the switch opening and closing status signal to the dispatching automation system through the reverse isolation device. When the status of the double position remote signaling displacement signal is consistent with that of the image analysis result signal, the "double confirmation" of the opening and closing positions is completed, and the one key sequential control process is automatically executed downward.

This function is applicable to the centralized control center of the substation operation and maintenance station. In order to comprehensively analyze the operation of the substation equipment, it is necessary to gather all the centralized data of the equipment. With the AR equipment as the carrier, various data can be added to the AR panorama, including visible light images, thermal imaging images and temperature data, and operating condition data collected by the third party and itself. These data are associated through the device tag. When you click the device tag on the screen, the associated monitoring data of the corresponding device pops up. When the structured monitoring data is abnormal, the data display on the screen will also alarm in red.

Big Data Kanban

Based on the big data billboard, the patrol task, temperature situation, environmental data, event alarm, etc. of the substation are statistically displayed.

The substation has realized the scene Internet of Things, deployed with intelligent cameras, infrared thermal imaging, face recognition all-in-one machine and various non video sensors.

Video monitoring equipment has intelligent perception function, which can realize safety helmet detection, anti misrun interval detection, smoking detection at the equipment end, and remind on-site personnel to stop violations in time through external voice column alarm or built-in audible and visual alarm. The all-in-one face recognition machine has the face comparison function, and the door can be opened by linkage if the comparison is successful.

The non video sensor mainly realizes the data acquisition function. It relies on the dynamic ring monitoring alarm host to trigger the alarm and threshold out of limit alarm. In addition to the linkage to open the corresponding camera image, switch the preset position, capture and record, it can also linkage the corresponding intelligent equipment to start, adjust the operating environment in the station, and ensure the stable operation of electrical equipment. In case of an emergency, even if the communication with the dispatch and control center is interrupted, the edge intelligence in the station can also be realized.

Front end system

The front-end system is mainly composed of video monitoring system, online monitoring system, one button sequential control auxiliary system, environmental monitoring alarm system, fire alarm system, access control visual intercom system, etc. It realizes the functions of image, video, audio and various environmental information collection and processing at the substation site, and carries out unified access, centralized monitoring, information aggregation and system linkage through the station platform, The data can be submitted through the power integrated data network.

The video monitoring system consists of the visible light monitoring subsystem, the track machine monitoring subsystem, the thermal imaging monitoring subsystem, the intelligent analysis equipment, and the hard disk recorder. The intelligent analysis equipment will realize the equipment status analysis, personnel behavior analysis, and environment status analysis, and the video information will be stored in the hard disk recorder.

The online monitoring system consists of an online temperature measurement subsystem and an online auscultation subsystem. The temperature and audio information will be stored in the hard disk video recorder.

The one key sequence control auxiliary system feeds back the analysis results to the sequence control host through soft message.

The environmental monitoring and alarm system is composed of environmental monitoring subsystem, intelligent control subsystem, security protection subsystem, etc. The dynamic environment monitoring and alarm host is connected to these subsystems through IO  4-20mA  RS485 to achieve environmental data acquisition, alarm signal input, and control signal output.

The core of the fire alarm system is the user information transmission device, which can realize the unified protocol conversion and remote transmission center of different fire alarm hosts.

The access control visual intercom system is composed of an integrated face recognition machine and a spiritual lock, which realizes the control of personnel access in the substation gate and main equipment rooms. It is opened by face recognition, central remote control, key, etc. When the entrants are not in the preset face database, they can call the dispatching center to open the door remotely through the visual intercom function built into the face recognition all-in-one machine. In case of abnormal conditions, the door can also be opened through the key.

System introduction

The operation and maintenance personnel conduct on-site inspection and make simple qualitative judgment on the sense of the operating equipment, which is mainly realized through the senses of seeing, smelling, listening, measuring and checking. In order to reduce the waste of travel time, it is necessary to realize online monitoring. Therefore, online temperature measurement and online auscultation subsystems are deployed.

Online temperature measurement subsystem

After online infrared thermal imaging is adopted in the substation, it can automatically inspect the temperature of the operating equipment in real time and send out an audible alarm signal according to the preset alarm value, and upload the alarm signal to the dispatch and control center in time, so that the personnel on duty can "find and process early", reduce the load or change the system operation mode, etc., to ensure the safety of equipment operation, and improve the operator's ability to identify and predict equipment defects.

The station terminal platform accesses infrared thermal imaging through NVR (and video monitoring system multiplexing), which can conduct real-time temperature measurement, management and monitoring of field operating equipment, and truly realize temperature structure, equipment networking, and intelligent early warning.

Thermal imaging PTZ

The thermal imaging PTZ supports left and right rotation and up and down rotation, so that infrared thermal imaging can monitor different areas and obtain images and temperatures of different monitoring targets. Compared with the thermal imaging ball machine, the thermal imaging PTZ has a larger elevation angle, which can be installed at the low position to measure the temperature of the high position equipment, such as the closing position of the main transformer bushing, knife switch and tube bus. It is easier to install at the low position for maintenance.

For narrow areas such as cable layer, the track machine is used to carry thermal imaging PTZ. Considering the bearing capacity of the rail machine, we have selected a dual spectrum MINI PTZ, with a thermal imaging image size of 640 * 512, and a 2 million 32 times white light camera for visible light.

Thermal imaging card machine

In the switch room of the substation, there are many high-voltage switch cabinets, which need temperature measurement. Since the switch contact is in the cabinet