Report

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.

News

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18 okt 2021


Pressure-time method test rig operational at LTU

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Tax Reduction for New Technology

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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


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About the report

Report number

2020:707

Author

Lena Max, Andreas Petersson, Pehr Hjalmarsson