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Smart City Development: The Path to Intelligent Upgrading of Ring Main Unit Switchgear

Release time:

2025-11-26

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Abstract

Smart City Development: The Path to Intelligent Upgrading of Ring Main Unit Switchgear

In the wave of smart city development, the intelligent upgrade of power systems serves as the core support for ensuring the efficient operation of urban infrastructure. As the "nerve nodes" of the distribution network, ring main unit switchgear play a critical role in electric power distribution, line interconnection, and fault isolation—functions whose advanced智能化 level directly impacts the reliability and safety of urban power supply. From traditional manual inspections to IoT-based sensing, and from passive emergency repairs to proactive preventive maintenance, the intelligent transformation of ring main units is rapidly emerging as a key breakthrough point for smart city power systems.

Traditional Dilemma: Outdated Equipment Limits Power Supply Reliability

For a long time, traditional ring main units (RMUs) have faced three major pain points: First, equipment aging leads to frequent failures. For instance, during a renovation project in 2025, State Grid Dengfeng Power Supply Company discovered that RMUs operating for over 15 years commonly suffered from issues such as stiff operation mechanisms and inadequate cooling—problems that caused failure rates to surge during peak summer electricity demand. Second, manual inspections are highly inefficient. Traditional inspection methods rely on regular human checks, making it difficult to detect hidden faults like insulation degradation or poor contact. As a result, the window for early fault detection is often just a few weeks at most. Third, there’s a lack of data-driven decision-making in operations and maintenance. Maintenance personnel typically depend on experience to assess equipment conditions, leading to costly yet limited effectiveness in preventive testing. These challenges are particularly pronounced in areas like Limei Community in Putian City and the old districts of Changsha, where aging RMUs have become a critical bottleneck hindering reliable power supply.

Technological Breakthrough: IoT Empowers All-Dimensional Perception

The deep application of IoT technology has provided crucial technical support for the intelligent upgrade of ring main units. Take partial discharge monitoring using the pulse current method as an example—this technology precisely captures transient current pulses generated by partial discharges by filtering within the 50Hz–5MHz frequency range. Combined with advanced feature extraction algorithms that analyze pulse amplitude, phase distribution, and repetition frequency, it enables the creation of a comprehensive discharge fingerprint database. In the renovation project of the 10kV Zhenyang Line in Putian City, the newly integrated ring main unit incorporates pulse current sensors along with temperature and humidity sensors, enabling non-contact, continuous monitoring. As a result, the fault early-warning window has been extended from several weeks to several months, while operational and maintenance costs have been reduced by more than 30%.

More advanced solutions further integrate multi-source data. For instance, ABB’s Safe Digital solution employs four-dimensional monitoring—tracking temperature, air pressure, mechanical characteristics, and partial discharge—and pairs it with an edge computing module that instantly compares these metrics against standard thresholds, triggering a three-level alert mechanism. In Changsha City’s smart grid demonstration project, this solution reduced the grid failure rate by 42% and boosted power supply reliability to an impressive 99.999%. Moreover, breakthroughs in wireless communication technology have effectively addressed the challenge of data transmission in remote areas. The dual-channel 4G/LoRa communication system ensures reliable data uploads, enabling operations and maintenance personnel to view real-time discharge intensity heatmaps via mobile devices—and even receive work orders that include precise information on the location and type of discharge, along with tailored recommendations for corrective actions.

Feature Upgrade: From a Single Device to a System Ecosystem

The intelligent upgrade not only enhances the monitoring capabilities of ring main units but also redefines the operational logic of the distribution system. The new-generation smart ring main unit features three core functions:

First, there’s the self-healing capability. By leveraging the distribution network automation system to achieve "three remotes" control—remote measurement, remote signaling, and remote control—the system can automatically pinpoint the faulty section of the line upon detection and remotely isolate it, while swiftly restoring power to unaffected areas. During the renovation of Qianjin Road in Erlianhot City, Inner Mongolia, the integration of primary and secondary equipment into a single ring main unit cabinet reduced fault isolation time from hours to just seconds, boosting power restoration efficiency by 90%.

Second, the predictive maintenance system. This equipment health assessment system, built on big data analytics, continuously monitors parameters such as switching operation counts, contact temperatures, and mechanical characteristics to predict equipment lifespan and generate maintenance recommendations. In the Dengfeng City renovation project, the system issued an early warning three months in advance about wear on a particular switch operating mechanism, successfully preventing a major power outage incident.

Third, energy management optimization. The intelligent ring main unit integrates electricity monitoring and load analysis functions, dynamically adjusting distribution strategies by comparing historical data with real-time loads. For instance, a ring main unit in a commercial district of Changsha City analyzed electricity consumption patterns and automatically switched to backup power during peak hours, effectively balancing the regional load and reducing line loss by 15%.

Future Outlook: Moving Toward Self-Healing Smart Grids

With the maturation of 5G network coverage and advanced deep learning algorithms, the intelligentization of ring main units is set to enter a new phase. The next-generation products will integrate AI-based fault classification technology, enabling automatic identification of fault types through pulse time-domain features, with the forecasted early-warning accuracy expected to exceed 95%. Meanwhile, digital twin technology will create virtual replicas of ring main units, allowing for simulation-driven optimization of operational parameters and ultimately helping organizations achieve their "zero-fault" goal.

Under the smart city framework, the intelligent upgrade of ring main units is not only an innovation at the equipment level but also a fundamental restructuring of the distribution system ecosystem. Shifting from "single-point monitoring" to "comprehensive global sensing," and from "manual decision-making" to "autonomous operation," these smart ring main units are becoming pivotal nodes in building self-healing, intelligent power grids. With each ring main unit equipped with an "electronic diagnostic tool," the pulse of urban power supply will grow stronger and more reliable, injecting powerful momentum into the sustainable development of the smart city.

Key words:

Daily Inspection and Maintenance of Switchgear Cabinets: The Secret to Extending Equipment Lifespan

Application of Box-Type Substations in New Energy (Photovoltaic/Wind Power) Projects

Hunan Chengyuan Electrical CO.,LTD

Smart City Development: The Path to Intelligent Upgrading of Ring Main Unit Switchgear