Cyber-physical energy systems modeling, test specification, and co-simulation based testing

The gradual deployment of intelligent and coordinated devices in the electrical power system needs careful investigation of the interactions between the various domains involved. Especially due to the coupling between ICT and power systems a holistic approach for testing and validating is required. Taking existing (quasi-) standardised smart grid system and test specification methods as a starting point, we are developing a holistic testing and validation approach that allows a very flexible way of assessing the system level aspects by various types of experiments (including virtual, real, and mixed lab settings). This paper describes the formal holistic test case specification method and applies it to a particular co-simulation experimental setup. The various building blocks of such a simulation (i.e., FMI, mosaik, domain-specific simulation federates) are covered in more detail. The presented method addresses most modeling and specification challenges in cyber-physical energy systems and is extensible for future additions such as uncertainty quantification

Ptolemy-HLA: A Cyber-Physical System Distributed Simulation Framework

The Ptolemy-HLA distributed co-simulation framework leverages two open source tools, Ptolemy II and HLA/CERTI, for the simulation of Cyber-Physical Systems (CPS). This framework enables dealing with three important issues: (1) Distribution of a simulation, allowing to scale up models and performance; (2) Interoperability of tools, allowing reusability and interfacing with other simulators or real devices/systems; (3) Heterogeneous simulations (discrete events, continuous time). The framework extends Ptolemy both, by coordinating the time advance of various Ptolemy instances, and by allowing data communication between them with the help of HLA management services. These additions enable the creation of HLA federates (i.e., simulators) in a Federation (i.e., a distributed simulation) in an easy way, since the user does not need to be an HLA specialist in order to design a Federate. The paper presents the new components added to Ptolemy, some semantic issues, an application example and performance analysis