Factors influencing oscillations within meshed HVDC grids and implications for DC voltage control

Abstract

Since meshed HVDC grids are discussed for offshore wind farms interconnection and onshore long distance transmission use, there is also a research focus on operation of such new type of grids. A major aspect is DC voltage control. Tests on a low voltage meshed HVDC mock-up system showed oscillatory behavior using state of research DC voltage control characteristics. This paper presents an analysis of influencing factors for these oscillations and proposes improvements for the DC voltage control characteristic, for the operation management and shows that converter parameters can invoke oscillations.