2013 saw the presentation of a paper  to the wind integration workshop, which demonstrated 26 high convertor penetration scenarios, 17 of which introduced a type of instability in RMS models previously unseen by the researchers. It also provided an indication of the constraints necessary if NSG levels where to be limited, potentially placing practical limits on the amount of NSG which could be accommodated. It demonstrated that Synchronous Compensation (SC) could be used to mitigate these and other problems but this is believed to be an expensive solution.
Further publications have demonstrated that convertor instability at high NSG extends beyond RMS models and is believed to occur in real systems . In addition, Swing Equation Based Inertial Response (SEBIR) control, sometimes referred to as "Synthetic Inertia", has been shown to be ineffective as a countermeasure against the instability observed in  and can in some circumstances make it worse . Whilst SEBIR improves RoCoF, its inability to address the wider range of problems resulted in the need for more comprehensive solutions.
Several authors have proposed converters using principles aligned with VSM and VSM0H concepts and controllers using these concepts exist within marine power networks.
This paper returns to the studies presented in , which used a reduced 36 node GB model in PowerFactory (PF). However here, some of the convertors are replaced with VSM convertor models described in  to investigate the effects on Instantaneous Penetration Level (IPL) limit of NSG in terms of transient stability and steady-state stability. These and further results presented demonstrate the potential of VSM, in mitigating the effects of various challenges associated with high NSG, potentially allowing 100% penetration.
- non synchronous generation (NSG)
- virtual synchronous machine (VSM)
- converter control
- penetration level limit
- power system stability