Autonomous Power System Topology Recognition With Distributed Wave Pulse Injection

KEUNE, B; REHTANZ, C.; MORALES, J

Simposio; CIGRE Symposium 2017; 2017

With the new service of automatic network reconfiguration in smart grids, the power system topology may experience multiple daily changes. Many other services such as network protection require knowledge about the topology in order to work reliably. This information is provided by network control centre or may be estimated via distributed sensors input. Consequently, adaptive functions like protection can adjust pick-up thresholds, reach settings and operate characteristics in reference to load flow conditions and the state of topology. However, if a crucial communication link to a distributed device or service within the power system becomes temporarily unavailable right before the sequence of network reconfiguration followed by an electrical fault incident, then it might suffer from severe underperformance as it cannot know the change in topology. Hence, a smart grid that relies solely on telecommunication for adaptive protection and automatic disturbance management might experience an extended delay in the process of fault locating and service restoration. However, both tasks are an imperative requirement to guarantee the supply of electric power and must be solved as fast as possible. Consequently, autonomous solutions for topology recognition must be developed for services that are distributed within the power system such as protection. This work proposes a novel smart grid service for autonomous topology recognition and presents some first simulation results of the IEEE-34 node distribution test system in MATLAB/Simulink®. Thereby, a modulated wave pulse is injected into the power system at a freely chosen node for different topologies. Its measured reflection pattern at the same site contains topological information which is processed and analysed regarding characteristic arrival times. Thus, the given topology can be determined with local measurements only.