Sub-synchronous oscillations between FPC wind farms, VSC-HVDC links and nuclear power plants

Sub-synchronous oscillations between large synchronous generators and voltage source converters, VSCs is an emerging topic with the increased penetration of grid connected VSCs. There are several different study methods used for evaluating the risk for sub-synchronous oscillations.

In this report, the study methods for sub-synchronous oscillations including large synchronous generators and VSCs are evaluated regarding the suitability for different systems. Also, converter design and control are described with focus on the contribution to sub-synchronous oscillations.

It is shown that there are screening methods suitable for finding risks for possible sub-synchronous oscillations. For evaluating the risk of oscillations between a certain synchronous generator and a VSC, there are frequency scanning methods that can be used together with time domain simulations.


Tax Reduction for New Technology

This year, the much-requested investment support for solar will be replaced Tax Reduction for green technology. The new deduction gives private individuals a tax reduction for material and labor costs. Amelia Oller Westerberg has investigated how the costs are distributed when installing solar cells on a residential roof.

16 mar 2021

Further steps taken to improve power quality and smart grid diagnostics

What are the root causes and the direction of power quality disturbances? Using machine learning-based methods the Gothenburg startup, Eneryield, has developed new ways of analysing these disturbances. Here you can read about ways in which this method can be made accessible for grid-operators.

3 nov 2020

Proof-of-concept acoustic measurements for dam safety

This recent report provides insight into experiments carried out to evaluate the potential for subsurface dam monitoring using passive seismic measurements utilising existing optical fibres. The experiment showed great promise and the researchers gave recommendations for further testing.

26 okt 2020

EFORIS model adopted by Stanfords Energy Modelling Forum

Within Energiforsks programme EFORIS, Function and role of the electricity market in society, a study was carried out on the economic effects of scaling down nuclear power. Read more about the findings and the modelling tools used here!

20 okt 2020

News archive


About the report

Report number



Lena Max, Andreas Petersson, Pehr Hjalmarsson