This paper presents a residential, round-trip, mixed ownership, electric car-sharing scheme with an optimized charging schedule, expressed as a mixed integer linear programming model. Representing the given travel demand as a graph, a mixed (shared and owned cars) ownership fleet configuration, with different trip fulfillment possibilities, is determined using maximal cliques. Next, a car-to-trip allocation model for feasible trip plans, with considerations for equal car utilization and charging price, is used to generate charging profiles for the fleet. The model and the outputs can be variously integrated into existing energy system modeling frameworks. A case study, using data from a test building with a residential car-sharing fleet in Munich, demonstrates the potential of the proposed models to derive meaningful operational insights for fleet and energy system planners. 92% of the recorded trips at the test building could have been feasibly accomplished with only 60% of the available cars.

Paper submitted to PSCC 2024. In this paper, we present a standard power-hardware-in-the-loop testing platform that can real-time simulate detailed air-source heat pump dynamics based on well-established modeling knowledge. Distributed air-source heat pumps can be potentially used for fast frequency response. However, using air-source heat pumps for rapid modulation cannot be based on the current assumptions of linear speed-power transient characteristic, which was developed for low-speed temperature control applications. Customized setups with experimental validation options are needed to design the new fast frequency response compatible heat pump controllers. Most power system laboratories struggle in building a customized air-source heat pump, which hinders the research progress. The proposed platform is relatively universal, can fit to different heat pumps with minor modifications and be implemented on standard PHIL emulators in power system laboratories. Emulation results, real-time implementation details and model complexity metrics are presented, to assist transference of the setup to other laboratoriesÂ

This paper presents the design, implementation and validation of a M-Class PMU on a general purpose embedded controller, concurrently used for inverter and grid control tasks, deployed over a unified real-time control environment. The rising number of embedded controllers in active distribution grid opens an opportunity for shared computation and instrumentation resources. Unified real-time control environments can efficiently coordinate multiple embedded controllers, IOs and models from different toolchain. The PMU in this paper, is implemented within the NI Veristand real-time control environment at CoSES laboratory in TU Munich. It uses the existing instrumentation and controller setup for inverter and prosumer control in an active distribution grid laboratory. The PMU passes all Mclass device accuracy tests set by the IEC/IEEE 60255-118-1 standard. The output is compliant to the IEEE-SA C37.118.2 messaging standard and connected to an open source PDC software. The proposed solution demonstrates the possibility of merging different grid control and operation functionalities within the unified Veristand RT control environment.

This paper demonstrates a Power Hardware-in-the-Loop (PHIL) implementation of a decentralized optimal power flow (D-OPF) algorithm embedded into the operations of two microgrids connected by a tie line. To integrate the static behavior of the optimization model, a two layer control architecture is introduced. Underneath the dispatch commands from the D-OPF, a primary control scheme provides instantaneous reaction to the load dynamics. This setup is tested in the PHIL environment of the CoSES Lab in TU Munich. In the experiment, the two microgrids cooperatively optimize their operation through an ADMM based unbalanced D-OPF. The operations is then benchmarked against the exclusive use of primary control, without D-OPF. The decentralized approach outperforms, but also shows minor inefficiencies of integrating optimization methods into the real-time operation of the system.

This paper describes the Power hardware-in-the-loop (PHIL) architecture and capacities of the CoSES laboratory at TU Munich. The lab brings together renewable resources, flexible grid topologies, fully controllable prosumer emulators, a real-time control environment, and an API access for external connection to the lab. The electrical and control design of the lab allows for sophisticated PHIL experiments with an user-friendly implementation. Two experiments are included, to validate the PHIL performance and demonstrate the use of PHIL infrastructure to investigate an OPF algorithm.

The paper has been submitted to PSCC 2022 and is currently awaiting reviews. This paper proposes and implements, a harmonic analysis algorithm for microgrid Power Hardware-in-the-loop (PHIL) experiments, when the point of common coupling (PCC) voltage cannot be directly wired to the local prosumer controllers due to long distances between them. Using frequency-shifting and filtering ideas, the voltage measurement is converted to magnitude and phase information. This is passed over an asynchronous communication link to another controller, where it is recovered into a waveform after delay compensation. The method allows for accurate power calculations and grid synchronization over distributed prosumer controllers. The proposed method can work at different execution rates depending on real time (RT) workload and is shown to be robust against step changes, harmonics and communication delays. The method is demonstrated with two PHIL experiments at the CoSES, TU Munich lab in grid connected and island mode.