Leveraging Private LTE Networks for Direct Transfer Trip (DTT) Systems

Interconnection of Distributed Energy Resources (DER), islanding detection and prevention is an important part of the electric utility industry's clean energy goals. IEEE 1547 Standard for Interconnecting Distributed Resources with Electric Power Systems recommends that an island be detected and removed within two seconds of an occurrence. Utilizing a Private LTE (PLTE) network for islanding prevention delivers several improvements over public carrier options, including enhanced latency, reliability, security for mission-critical grid protection applications and simplified communication interconnection for DERs. The most common type of communication-assisted islanding detection and prevention is Direct Transfer Trip (DTT). This method requires communication technology between the potential isolating sources and the DER. When an isolating source is opened, creating an island, a DTT signal is sent to the DER. As with all communications assisted methods, communication technology is critical to the functioning of the system. Private LTE is a foundational technology that provides connectivity to many types of utility applications. Private LTE networks for DTT applications are a compelling choice due to their high availability, low latency, and high performance while optimizing the total cost of ownership. Private LTE-enabled DTT applications significantly improve latency and reliability compared to public networks. This paper explores utilizing Private LTE cellular networks for DTT anti-islanding applications. The aspects which are considered include the reliability of the network, cyber security, performance requirements and redundancy options. This paper provides data and results from the lab test conducted using RFL GARD 8000 devices on a QoS-enabled private LTE network. The test results show that a private LTE wireless network provides a communications network with a high level of reliability and deterministic latency for wireless protection applications.