  The electrical power network is gradually migrating from a centralized
generation approach to a decentralized generation with high shares of renewable
energy sources (RES). However, power systems with low shares of synchronous
generation and consequently low total system inertia, are vulnerable to power
imbalances. Such systems can experience frequency stability problems, such as
high frequency excursions and higher rates of change of frequency even under
small disturbances. This phenomenon is intensified when the grid under
investigation has low or no interconnections (islanded) and thus the challenge
for stable operation becomes more significant for the operators. This work
focuses on how the frequency stability is affected when a photovoltaic (PV)
inverter is integrated into a real non-interconnected distribution grid in
Cyprus. In order to capture the realistic interactions of this integration,
stability experiments in a hardware-in-the-loop (HIL) environment are performed
with the aim to provide insightful results for the grid operator.
