## 7 Conclusions  
In this paper, the performance of DVC when implemented in an EMT average model of Type-4 WG connected to a 66 kV equivalent HVAC system in RSCAD is presented. The test is performed for the most severe disturbance, that is, the three-phase line to ground fault. The three-phase line to ground fault is implemented in the middle of the 66 kV HVAC cable. On viewing the voltage profile at the PCC following the fault, it is observed that DVC provides stable operation in terms of short-term voltage stability. This is due to the fast control action of the local voltage control in the reactive power loop of the DVC to support the PCC voltage during the time of the fault. In terms of reactive current injection, the DVC provides active current priority during steady state conditions and reactive current priority during the time of the fault, which is an important requirement by most of the grid codes. The effect of damping during the time of fault is controlled by the washout filters in the active and reactive power control loops. A parameter sensitivity analysis is performed for the washout filters to assess the effectiveness of damping. The performance of the implemented DVC in a average model of Type-4 WG in RSCAD for a 66 kV HVAC network is then compared with the benchmark DVC for a simplified Type-4 WG model in PowerFactory for a similar 66 kV HVAC network. The comparison is made in terms of short-term voltage stability and reactive current injection following a three-phase line to ground fault in the network. A three-phase line to ground fault in the middle of the HVAC cable is simulated in both the models in EMT platform. The voltage, active and reactive current profiles are compared and found to have good correspondence following  
Figure 14: Active currents flowing to the network for a three phase fault in the middle of the cable. Figure 15: Reactive currents flowing to the network for a three phase fault in the middle of the cable. the three-phase line to ground fault. This shows the validation of the DVC implemented in the average model of the Type-4 WG for a 66 kV HVAC offshore network in RSCAD. Moreover, it is observed that the model developed in RSCAD has slight transients in the active and reactive currents throughout the simulation. This is due to the detailed model representation of GSC in RSCAD when compared to the simplified model in PowerFactory. These results show that the RSCAD model provides a better detailed representation of the real-world operation of the implemented DVC and can be used as a reference model. The way DVC is modelled to provide voltage support during the time of fault in 66 kV HVAC network are in line with the results from previous studies, in which DVC is implemented for a 33 kV HVAC network as explained in Reference [9]. As an extension of this research, the DVC can be implemented for single-phase faults by developing a negative sequence control loop. The study can be extended for Type-3 WGs which consist of the Double Fed Induction Generator (DFIG) and selective fault analysis can be performed. Due to the increasing demand for offshore wind energy, the expansion to create large scale offshore networks (greater than or equal to 2 GW) with implemented DVC also needs to be investigated as future work. Conceptualization, S.G., A.P. and J.R.T. ; formal analysis, S.G., A.P. and J.R.T. ; investigation, S.G., A.P. and J.R.T. ; methodology, S.G., A.P. and J.R.T. ; resources, S.G., A.P. and J.R.T. ; software, S.G., A.P. and J.R.T. ; supervision, J.R.T., A.P., P.P. and M.v.d.M. ; validation, S.G., A.P. and J.R.T. ; visualization, S.G., A.P. and J.R.T. ; writing--original draft, S.G., A.P. and J.R.T. ; writing--review & editing, S.G., A.P., J.R.T., P.P. and M.v.d.M. All authors have read and agreed to the published version of the manuscript. This research received no external funding. Data Availability Statement: Data sharing not applicable. This research was fully funded by Delft University of Technology.