Control of HVDC Diode Rectifier connected off-shore wind farm during cable faults in multi-terminal HVDC grids

摘要

The presented work shows the proof-of-concept operation of a HVDC diode rectifier (DR) station connected a multi-terminal HVDC grid. Previous work by the authors and others has shown that a wind power plant WPP can adequately control the off-shore ac-grid frequency and current and also deliver optimum power to the HVDC grid mainly in point-to-point configuration. This work aims to show the operation of the HVDC-DR in a multi-terminal HVDC grid and to study up to which extent the WPP control can be used to minimise the currents flowing through the HVDC-DR station during cable (pole-to-ground) faults. It has been found that reasonably fast DR station current reduction can be achieved and hence an active control of the WPP can help on simplifying the protections of the DR station in a muti-terminal environment.