Enhanced virtual synchronous machine (VSM) control algorithm for hybrid grid forming converters

There has been considerable interest in convertor solutions which to a greater or lesser extent mimic the behaviour of synchronous machines, thus overcoming many of the disadvantages of the existing technology which are potentially destabilizing at high penetration. These solutions are frequently referred to as Grid Forming Convertors (GFC).

For offshore installations, where some equipment is on shore, locating equipment offshore is more expensive and carries greater commercial risks, requiring extensive testing and confidence building prior to deployment in real applications. This is time consuming and particularly significant for GB and where there are significant quantities of offshore generation. Onshore solutions to stability are therefore desirable for Off-Shore Transmission Owners (OFTOs) and might also be applied by retrofitting to existing conventional converter plant.

This paper presents and discusses findings of the second stage of the research focusing on the enhanced control algorithm for Hybrid Grid Forming Convertors for Offshore Wind Applications and its performance, while the previous paper [3] presents the initial findings comparing various hybrid solutions for offshore networks where the STATCOM onshore is replaced by synchronous compensator and GFC or Virtual Synchronous Machines (VSM) converter of similar rating with the aim to achieve levels of Grid-Forming capability.