Increasing Offshore Wind Infeed Using HVDC Dynamic Capacity in Transmission Capacity Management

GCS (one failed one in operation) is possible. In this case, the generating offshore capacity is up to two times higher compared to the transmission capacity of the remaining GCS. Due to this fact, an optimizing control function for the energy infeed during outages is necessary in order to prevent the remaining GCS from overload. This function is called Transmission

Capacity Management (TCM), which results in vastly reduction of compensation payments especially during low wind scenarios. However, TCM reserves a ramp-up margin for the 1 regularly connected power plant module (R-PPM), limiting capacity for the temporarily connected power plant module (T-PPM). This can lead to unused transmission capacity of the

GCS under certain wind- and infeed conditions.

This study investigates the added value of incorporating dynamic capacity—the ability of VSCHVDC systems to temporarily exceed nominal ratings—into TCM operation. Using an example 48-hour outage scenario, results show that the application of dynamic capacity would increase the total energy infeed by up to 2.8% (R-PPM + T-PPM) and reduce the curtailment of the TPPM by 9.7%, while actual operation above nominal rating remains rare, short (< 30 seconds), and minimal (< 2% of nominal converter rating). The primary benefit—derives from algorithmic optimization rather than sustained higher loading, resulting in negligible technical stress to the systems involved.

The findings indicate a positive economic and societal impact, though benefits depend on outage duration, wind conditions, and system configuration. Implementation requires monitoring, software integration, and regulatory adjustments. Overall, dynamic capacity integration could offer significant potential for optimizing offshore wind energy transmission with minimal risk.