Submission 161
Technical Assessment of GFM E-STATCOM and GFL Offshore Windfarm as Combined Solution for Weak Grid Connections
01 GIW26-161
Presented by: Ben Gomersall
The National HVDC Centre, United Kingdom
The increasing integration of converter-connected renewable generation in Great Britain (GB) has led to the risk of reduced system inertia and weakened short-circuit strength given the loss of conventional sources of support, which has the potential to present challenges for maintaining frequency stability and secure operation and design of offshore wind-connection. This paper investigates the coordinated operation of a grid-following (GFL) offshore wind power plant (OWP) and a grid-forming (GFM) E-STATCOM equipped with energy storage as a combined solution for weak grid connections. The work presents key findings from a follow-on project to the Carbon Trust’s Offshore Wind Accelerator (OWA) INCENTIVE programme, assessing the capability of the combined system to meet GB Grid Code requirements under a range of operating conditions. The assessment includes frequency disturbances, phase-angle events, voltage and fault studies, together with impedance-based stability analysis using small-signal injection techniques. Time-domain simulations were performed in PSCAD to evaluate dynamic performance, while impedance characteristics and stability margins were assessed using PSCAD and MATLAB. Results show that the GFM E-STATCOM provides rapid inertial-type support that complements the sustained frequency response of the OWF, providing voltage recovery, damping, and overall system resilience. The coordinated solution demonstrates stable operation under weak-grid conditions with no adverse interactions observed within the limited scope of tests. These findings indicate that combining offshore wind generation with grid-forming technology offers a practical pathway to supporting secure and reliable operation of future low-inertia power systems.