—W H I T E PA P E R The role of cutout-based reclosers in modern grid protection Eagle single-phase recloser The aging of electrical grid infrastructure, coupled with the profound impact of climate change, has elevated the importance of helping ensure and reinforce the reliability of electrical distribution systems. Among key components, automatic circuit recosers stand out as crucial guardians that defend against faults and interruptions. This white paper explores the role of reclosers in alternating current systems, their interaction with distributed generation and related aspects. Automatic circuit reclosers Automatic circuit reclosers serve as centers that help ensure the proper functioning and safety of distribution networks. Designed to quickly stop the flow of electrical current upon detecting a fault, these protective devices quickly isolate the problematic segment. After a brief delay, reclosers attempt to restore power, helping minimize downtime and preserve network functionality. In distribution networks, reclosers act as a primary defense against various failure triggers, including interference from trees, contact with animals and other unforeseen factors. Hydraulic and electronic reclosers are the two main types, and they use different mechanisms to interrupt current. While hydraulics rely on hydraulic systems for switching, electronic variants use solid-state electronics. Electronic reclosers have gained importance due to their superior reliability and adaptability in various network scenarios. The recloser’s strategic location along distribution feeders plays a critical role in mitigating the impact of wildfires. Particularly in rural regions, reclosers disconnect the feeder, allowing power to be restored to unaffected areas while faults are accurately identified and rectified. Additionally, the integration of reclosers with complementary protective devices, such as fuses and sectionalizers, allows for cohesive and synchronized shielding against potential electrical faults. Overall, strategic deployment and integration of automatic circuit reclosers within distribution networks not only improve network resilience but also significantly contribute to maintaining uninterrupted power supply and protecting against potential disruptions caused by various external factors. — 01 Medium voltage overhead rural line — 01 Effects of distributed generation on protection systems The rise of distributed generation, exemplified by the proliferation of solar panels and wind turbines, continues to exert a substantial influence on energy grid protection systems. This paradigm shift introduces complexities, particularly in the potential variability of fault current, which poses challenges in coordinating protective devices seamlessly. Furthermore, the integration of distributed generation sources can inadvertently trigger islanding scenarios, isolating segments of the distribution network and causing localized outages. Addressing these pressing challenges involves strategically deploying reclosers and sectionalizers, particularly in rural distribution networks, to strengthen system reliability. Functioning as integral protection components, sectionalizers exhibit an automatic ability to quickly isolate faulty segments within the network. This strategic isolation facilitates the restoration of power to unaffected areas, minimizing downtime and improving overall grid resiliency. When combined with reclosers, these sectionalizers contribute to a comprehensive and coordinated protection strategy, effectively managing faults and hardening the system against disruptive events. The synergistic implementation of sectionalizers and reclosers not only improves the protection capabilities of distribution networks, but also lays the foundation for a more robust and adaptable energy infrastructure capable of meeting the complex challenges posed by the growing distributed generation landscape. Reclosers with circuit breakers on distribution- side circuits Circuit breaker reclosers, which leverage a circuit breaker as the primary interrupting device, are emerging as vital components within electrical distribution systems. Their widespread use in distribution-side circuits means an optimal fusion of reliable protection and cost-effectiveness, outperforming alternative recloser types in several respects. The inherent advantage lies in its ability to help ensure reliability while managing expenses effectively. Stationed primarily on distribution-side circuits, switch reclosers serve as robust gatekeepers and offer protection aligned to different system needs. Their versatility allows optimal integration with supplementary protection mechanisms, such as fuses and sectionalizers. Working together, these devices orchestrate a well-coordinated defense, quickly identifying faults and restoring power, thus helping ensure minimal network disruption. The effectiveness of these protective measures, however, depends largely on meticulous coordination between the devices. It is imperative to select protective devices that harmonize well together, facilitating a synchronized response to electrical irregularities. Achieving this synchronization requires a thorough evaluation of protective equipment along with the implementation of sophisticated communication and control systems. Seamless collaboration between these protective layers not only helps ensure rapid fault isolation, but also accelerates power restoration, helping minimize downtime and reinforcing the overall resilience of the power grid. As technology advances, the evolution of communication and control systems continues to refine this coordination, improving the system’s ability to respond to contingencies rapidly and efficiently. — 02 Eagle recloser with circuit breaker configuration — 02 Eagle recloser with SCADA capabilities The Eagle single-phase recloser represents a significant advancement in recloser technology by integrating long-range communication and SCADA (supervisory control and data acquisition) capabilities via the DNP 3.0 protocol. Designed to provide real- time information on system performance and failure occurrence, this cutting-edge device allows operators to quickly detect and respond to potential failures, helping ensure greater network reliability. The versatile Eagle recloser serves as an integral component within a comprehensive protection network and combines well with other protection mechanisms, such as fuses and sectionalizers. Together, they provide a robust shield against service outages and offer coordinated protection for electrical systems. Getting the most out of the Eagle recloser requires detailed attention to proper installation and ongoing maintenance. Installation procedures involve strategic placement within the network, helping ensure correct grounding and seamless integration into the distribution framework. Sustained reliability depends on regular maintenance, including thorough inspections, routine testing and prompt replacement of any worn or damaged components. As utilities increasingly rely on sophisticated grid solutions like the Eagle recloser to bolster efficiency and reliability, emphasis on proper installation and diligent maintenance becomes critical, helping safeguard the uninterrupted flow of electricity and mitigate possible interruptions and downtime. Economic analysis of automatic distribution feeder sectioning Economic analysis stands as a fundamental determinant in the strategic selection of protection devices within distribution networks. This exhaustive process involves comparisons of costs and benefits associated with different protection mechanisms, considering elements such as initial equipment expenses, ongoing operating costs and the impact on customer spending. Two widely used protection devices within distribution networks are circuit breakers and reclosers, each of which exhibits distinctive attributes. Fused circuit breakers, although initially more cost-effective, provide limited protection and require more frequent replacement. In contrast, reclosers require a larger initial investment but offer higher levels of protection and require less frequent replacement. The practical application of economic analysis is illustrated through case studies. These studies serve as illuminating examples by contrasting the costs and benefits inherent in employing reclosers versus fused circuit breakers on a specific distribution feeder. The results of such analysis provide valuable information to guide the selection of protective devices designed for optimal performance within the electrical system. — 03 Long range communication (LRC) for Eagle recloser — 04 Eagle Installation — 05 Eagle dashboard — 03 — 04 — 05 — We reserve the right to make technical changes or modify the contents of this document without prior notice. With regard to purchase orders, the agreed particulars shall prevail. ABB Inc. does not accept any responsibility whatsoever for potential errors or possible lack of information in this document. We reserve all rights in this document and in the subject matter and illustrations contained therein. Any reproduction, disclosure to third parties or utilization of its contents – in whole or in parts – is forbidden without prior written consent of ABB Inc. Copyright© 2024 ABB All rights reserved — ABB Inc. 305 Gregson Drive Cary, NC 27511 abb.com/mediumvoltage9AKK108469A4809 REV A MAY 2024Conclusion Automatic circuit reclosers play a critical role in maintaining the robustness of contemporary electrical distribution systems. Their importance lies in maintaining reliability and security standards amid fluctuating conditions within the network. The changing landscape, influenced by distributed generation and various other challenges, demands careful evaluation of protection mechanisms and their ideal coordination. Delving deeper into the complexities of design, functionality and economics associated with these devices becomes imperative. This comprehensive knowledge allows us to effectively contribute to the sustained functionality and resilience of our electrical distribution networks. As we navigate an era marked by technological advancement and increasing demand for energy efficiency, the role of reclosers and their associated systems becomes even more pronounced. A recloser’s ability to quickly detect, isolate and mitigate failures contributes significantly to helping prevent wide- spread outages and protect critical infrastructure. Furthermore, the current evolution of renewable energy integration into the grid requires a re-evaluation of recloser functionalities to adapt to this dynamic landscape. As we strive towards a more sustainable energy future, understanding the interaction between traditional grid elements and emerging renewable technologies is critical to maintaining the reliability and stability of our electrical systems. In essence, a comprehensive understanding of reclosers, their operations and their symbiotic relationship with the broader electrical distribution infrastructure is essential to help ensure the smooth functioning and resilience of our electrical networks in an ever-evolving environment.