Resilience of the DSO network near to 50.2Hz

In an electrical system where decentralized and embedded productions are becoming more and more important, it is essential to ensure there is a good understanding of their behaviour at their operating limits. One the most important operating limits is when the system frequency approaches 50.2 Hz. At this frequency, following the old requirements, many existing European PV inverters have to be disconnected. In such situations, we will demonstrate that the variance of the frequency measurement taken at every PV inverter plays a key role. It will be demonstrated that this variance is actually a good thing from the system’s point of view as it allows for a gradual disconnection, leading to a controlled variation of the frequency.