Sub-synchronous oscillations monitoring in power systems

 

Power system dynamics are becoming increasingly due to the operational challenges linked to some renewable power production/dispatching.

As an example, in December 2010, oscillations during periods of high wind generation were observed on the transmission system in northwestern Oklahoma. They caused 5% fluctuation of the system frequency of a magnitude of 14-15 Hz. The oscillations were brought about by interactions between the controllers of two different wind farms. The countermeasures taken were to electrically isolate the wind farms and to consequently curtail the wind power output.

In order to monitor rapid changes, Phasor Measurement Units (PMUs) - providing 50 or more samples per second - can be exploited to develop more accurate monitoring capabilities.

 

To better monitor renewable energy sources (particularly wind farm) production and interaction, we are therefore developing a joint project with KTH Sweden and IREQ Spain.

This project focuses on designing software tools that will allow monitoring wind farms output using real-time data streams from PMUs and the detection of renewable energy sources production interactions.

Among the envisaged deliverables: design of a detailed model of the power system including its components and wind farms (specifically type 3 wind turbines - Double Feed Induction Generators and type 4 wind turbines - Converter connected Synchronous Generators).