The efficient operation and maintenance of electrical substations are crucial to ensuring reliable energy supply. In recent years, the increasing complexity and demands on electrical infrastructure have highlighted several challenges in substation monitoring and maintenance. Traditional methods often fall short in providing the necessary real-time insights and early warnings needed to prevent failures and ensure continuous operation. The implementation of advanced monitoring technologies, such as automated visual and thermal systems, represents a significant advancement in addressing these challenges.
The focus substation is located in Santa Marta, Colombia, and plays a vital role in the regional power distribution network. The company is a leading Colombian organization dedicated to the transmission of electricity, ensuring reliable and efficient energy supply across the country.
This project focuses on an extra high voltage substation, where an automated system integrating high-resolution PTZ, thermographic and IoT cameras were deployed. The system's objective is to enhance the remote monitoring capabilities, allowing for timely detection of thermal anomalies and other failure modes through advanced analytics. This paper details the system components, their installation and observed benefits, including specific instances where early detection of anomalies prevented potential failures and significant financial losses. The integration of these technologies into the existing SCADA system further supports remote decision-making and operational efficiency.
The operation and maintenance of electrical substations are essential to ensure reliable energy conditions. Over the years, various challenges have emerged, driving the need to seek more advanced solutions. The following are some of the challenges experienced in monitoring electrical substations:
2.1. Challenges in early detection of thermal anomalies
Electrical substations are subject to a variety of failure modes and abnormal conditions that can jeopardize operation and safety. Identifying these anomalies early is challenging but crucial to avoid unplanned interruptions and equipment damage. Thermal anomalies can result from issues such as contact problems, irregular loads, insulation cracks defective relays. These issues increase the internal temperature of electrical equipment, leading to shortened life expectancy of the asset, unexpected disturbances and potential damage to power systems.
Specific examples of where these issues can occur include:
Two factors make early detection of thermal anomalies particularly challenging:
Early detection using infrared thermography is essential to prevent equipment failure and ensure the reliability of the power grid. However, these challenges must be addressed to improve the accuracy and effectiveness of thermal monitoring in substations.
2.2. Inaccessibility to critical areas
Some areas of electrical substations can be difficult or even dangerous for personnel to access. This inaccessibility can hinder the inspection and maintenance of equipment in critical areas, leading to poor supervision. Specific examples of inaccessibility challenges include:
2.3. Need for continuous supervision
Substations operate 24/7 and require continuous supervision to ensure optimal functioning. The increasing complexity of electrical networks and the integration of distributed energy resources necessitate constant monitoring to maintain reliability and address any issues promptly. Continuous condition monitoring using sensors and advanced technologies provides real-time data on critical variables such as temperature, humidity and electrical parameters. This data helps in early detection of potential failures, enabling timely maintenance and reducing the risk of unplanned outages4-5.
Additionally, the growing demand for electrification, such as electric vehicles (EVs) and renewable energy sources, has increased the load on electrical substations. These changes in load over time can create new challenges for substation management. For example:
The implementation of an automated visual and thermal monitoring system represents a significant technological advancement in substation monitoring. This system integrates a variety of advanced components and sensors that enable advanced, real-time supervision, detecting anomalies and generating automated responses. Below is a detailed description of the key aspects of the implemented system.
3.1. System components
The automated monitoring system comprises several essential components that work together to provide comprehensive and effective substation supervision:
3.1.1. Visual monitoring sensors: Visual monitoring sensors (Figure 1) are essential for capturing high-resolution images of equipment, connections critical areas within substations. These sensors provide detailed visual information for remote inspection and analysis problem detection. To ensure reliable operation in harsh substation environments, these sensors must comply with IEC61850-3 standards. Enhanced features such as smart infrared capabilities for night vision, automated patrolling presets multiple presets for video analytics with intelligent motion detection functions improve their functionality. These features enable real-time visualization and remote inspection, making them crucial for safety and security asset monitoring in challenging conditions.
3.1.2. Thermal infrared sensors: Thermal sensors (Figure 2) are essential for detecting temperature anomalies in electrical equipment and systems by capturing infrared light emitted by objects, which is invisible to the human eye. These sensors, equipped with mobility systems and communication capabilities via the IEC61850 protocol, are crucial for identifying hotspots and incipient failure modes. They facilitate the detection of overheating and hot spots by capturing temperature-based images and data. Additionally, thermal sensors offer multiple presets, allowing the configuration of different regions of interest per preset and generating temperature readings and thermal alarms associated with each analyzed object, enhancing their functionality and precision. These sensors must be able to operate reliably under harsh conditions, including high levels of EMI, ESD, voltage surges temperature extremes.
3.1.3. Onsite servers: Onsite servers (Figure 3) are crucial for substation monitoring and managing storing data from various sensors and cameras. Local analysis and storage of video and thermal data minimize the use of bandwidth on the operations network and improve system reliability in case of network failures, ensuring continuous, dependable monitoring and alarm notification under challenging conditions. These servers must be designed and built to withstand harsh substation conditions, with no fans or moving parts be equipped with industrial-rated power supplies and solid-state drives. Complying with IEC61850-3 and IEEE1613 standards ensures reliable operation in environments with high levels of EMI, ESD, voltage fluctuations extreme temperatures.
3.1.4. IoT sensors: These sensors (Figure 4) play an essential role in monitoring confined spaces within substations, such as inside switch gears or underground vaults. These sensors provide both thermal and visual data, enhancing situational awareness and asset health management in these challenging environments. These sensors must be designed for electric power applications and must be able to operate reliably under harsh conditions, like high levels of EMI and ESD voltage surges.
3.1.5. Communication systems: All cameras and sensors used in the system are equipped with communication systems that enable real-time data transmission based on the IEC61850 standard to a SCADA interface located in a control center. This facilitates remote supervision and decision-making.
3.1.6. Control platform: A software-based control center (Figure 5) provides the user interface for monitoring and controlling the sensors, visualizing data receiving alerts in case of anomalies.
3.2. System Architecture
The system was designed to deliver analytical signals to the substation's main controller for supervision across various operation levels. The video server not only delivers signals to the local system but also provides real-time video to the control center.
The primary goal of sensor placement is to efficiently supervise and analyze the maximum number of assets and equipment, thereby optimizing resource implementation. The system incorporates three thermal sensors with analytics, covering 576 thermal tracking positions, which monitor 96% of the substation's power equipment. Thermographic sensors for equipment supervision are strategically located to ensure their visual field includes the substation's transformers.
Additionally, six visual cameras with 1152 viewing positions have been installed. These cameras can be remotely accessed via SCADA for visualization or from the central monitoring station or the substation's HMI monitoring. This setup offers significant benefits, including estimated savings on night trips to the substation for verifying maneuvers in robotized metal-clad cells. The placement of these cameras was determined to support operations by providing the control center with a clear view of remotely executed maneuvers. Figure 6 shows the overall architecture of the solution.
Early detection of thermal anomalies in critical power system components was successfully achieved, leading to significant preventive measures and cost savings:
These anomalies were promptly reported through the substation's Supervision and Control System (SSC) and communicated via email to the designated engineers, ensuring timely intervention and mitigation of risks.
The implementation of an automated visual and thermal monitoring system at the Substation has demonstrated substantial benefits in enhancing the reliability and efficiency of substation operations. By integrating high-resolution PTZ and IoT cameras with thermographic sensors, the system has significantly improved the early detection of thermal anomalies and other potential failure modes. The advanced analytics and real-time data transmission to the SCADA system have enabled rapid and informed decision-making, ultimately preventing costly failures and ensuring uninterrupted power supply.
Key achievements of the project include the successful identification of critical thermal anomalies, such as the initial thermal anomaly in the 34.5 kV bushing of a 100 MVA transformer, which averted a potential fire hazard and significant financial loss. The proactive detection and timely response to issues in power cable terminals and metal-clad cells further highlight the system's efficacy in maintaining operational integrity.
The integration of these advanced monitoring technologies offers a robust solution for remote substation supervision. The project's success underscores the importance of continuous innovation and the adoption of cutting-edge technologies in the energy sector to address evolving challenges and ensure the stability of power distribution networks.
Future recommendations include the expansion of such automated systems to other substations within the network, continuous improvement of the analytics algorithms for even more precise anomaly detection and the exploration of additional IoT-based solutions to further enhance the scope and depth of substation monitoring. These steps will contribute to the overarching goal of achieving a resilient and reliable electrical infrastructure capable of meeting the growing demands of modern energy consumption.
This article was originally published on Electric Energy Online: