## 4 Results from Case Studies
### Dynamic Grid Simulations  
#### 4.1.1 Grid Topology and Key Assumptions  
For the _HVSim_ dataset, a single-phase grid model based on the ENTSO-E European Transmission System is used to facilitate the modelling and the analysis of the dynamic behavior of the power  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Dataset** & **\begin{tabular}{c} **\# of PMU** \\ **Stations** \\ \end{tabular} & \begin{tabular}{c} **Measurement** \\ **Channels [a]** \\ \end{tabular} & \
\begin{tabular}{c} **Voltage** \\ **Level** \\ \end{tabular} &
\begin{tabular}{c} **Reporting** \\ **Rate** \\ \end{tabular} \\ \hline _LVField_ & 5 & F, VAMP, VANG, IAMP, IANG, FC & 0.4 kV–20 kV & 10 f.p.s. \\ _MVField_[62] & 6 & F, VAMP, VANG & 0.4 kV–120 kV & 30 f.p.s. \\ _HVSim_ & 21 & F, VAMP, VANG & 400 kV & 25 f.p.s. \\ \hline \hline \end{tabular}  
* [a] F... frequency, VAmp... voltage amplitude, VAng... voltage angle, IAMP... current amplitude, IANG... current angle, FC... rate of change of frequency.  
\end{table}
Table 5: Overview of used datasets within this study.  
system. The 380 kV transmission system consist of 33 substations, where each interconnection consists of multiple circuit transmission lines to ensure the N-1 criteria. In order to emulate the dynamic of the system under outage conditions or load/generation changes, some generator units are equipped with Automatic Voltage Regulators (AVR) and Power System Stabilizers (PSS) to ensure the system stability in the simulated scenarios. Furthermore, multiple protection mechanisms for generators and lines are modeled. The frequency protection maintains the generator connected for frequency ranges between 47.5 Hz to 51.5 Hz and disconnects them otherwise for 5 s to 30 s to preserve the technical integrity of the equipment. Additionally, a fault-ride-through (FRT) capability for the generators protects the equipment under long duration short circuits. Finally, a simple maximum loading protection schema is implemented for the lines, which allows a line overloading for short time periods (<5 s). The implementation of these protection scheme allows simulating cascading effects for certain grid states. The basic grid topology with station and line labels is given in Figure 9. In a preprocessing step, different generation and load conditions are evaluated using optimal power flow (OPF) simulations. For a selected number of suitable steady states or operational points, different contingencies are simulated using RMS symmetric simulations with 1 ms time steps. A DIgSILENT(r) Programming Language (DPL) script controls the simulations with regard to events creation, stability check and saving of the results. For each operational point, about 440 different contingencies are simulated considering generator outages, line trips, short circuits at different line positions, partial photovoltaic (PV) outages as well as partial load losses. An online assessment of the simulated signals checks the system stability and aborts the current simulation in case of violations of predefined frequency or voltage limits. The RMS values are averaged to extract PMU signals at the given temporal resolution of 40 ms (corresponds to 25 f.p.s.). Compared to field measurements, the phasor estimation procedure and consequent signal deviations (e.g., filtering effects) are neglected.  
Figure 9: Topology of the generic transmission system model.