A hierarchical Wind Farm Control (WFC) approach was previously developed that uses Power Adjusting Controllers (PACs) on each wind turbine in a wind farm. The PACs can be retrofitted to existing assets with no knowledge of, or change to, the wind turbine full envelope controller (FEC). However, knowledge of the wind turbine aerodynamics is required and is not usually directly available from the Original Equipment Manufacturer (OEM), necessitating estimation. In this work, estimated aerodynamic properties are obtained via a scanning LIDAR that directly measures the shape of a 2.5MW commercial wind turbine’s blades. The impact of the resulting aerodynamic uncertainty on the PAC tuning and the accuracy of the change in power output from the PAC at a turbine level and at a wind farm level is assessed. It is shown that it is possible to tune a stable PAC using aerodynamic information estimated via blade scanning. Although the requested turbine change in power suffers from some inaccuracy, the slow integral action at a WFC level causes the impact on the accuracy of the change in wind farm power output to be negligible. As such, the application of a WFC methodology utilising PACs without prior knowledge of the turbine aerodynamics is shown to be possible by using blade scanning to estimate the aerodynamic coefficients. Hence it is practical to retrofit the methodology to wind farms when aerodynamic information from the OEM is not available.

This paper presents the findings from the initial phases of the SIF BLADE project, focused on demonstrating the capabilities of an offshore wind power plant (OWPP) for power system restoration (PSR). It provides an overview of PSR, highlighting its challenges and operational requirements, alongside the various scenarios considered in the project. The study includes a steady-state analysis to assess whether the OWPP can meet local network demands for both active and reactive power. Results indicate that the OWPP can operate within an envelope that covers all local power requirements. Additionally, electromagnetic transient (EMT) analysis was conducted to evaluate different percentages of grid-forming (GFM) converter penetration during the energisation process. These analyses aimed to determine compliance with transmission system operator (TSO) requirements. Findings demonstrate that all GFM penetration levels met the necessary TSO standards. Furthermore, a novel small-signal analysis was performed to identify the optimal percentage of GFM converters for enhancing system stability during block loading. The analysis suggests that for top-up scenarios, a GFM penetration between 20% and 40% is optimal, while for anchor scenarios, 40% to 60% GFM penetration enhances stability and robustness.

Offshore wind farms are increasingly being commissioned farther from shore, and high voltage alternating current (HVAC) transmission systems are preferred because of their maturity and reliability. However, as cable length increases, ensuring system stability becomes more challenging, making it essential to investigate shunt reactor compensation configurations and converter control strategies. This study examines three different shunt reactor compensation arrangements and two control strategies, grid-forming (GFM) and grid-following (GFL), across three cable lengths (80 km, 120 km, and 150 km). The systems were evaluated based on small-signal stability using disk margins for different active power operating points, and later for different short-circuit ratios (SCR) and X/R. The results demonstrate that the GFM is preferable for longer cables and enhanced stability. The most robust configuration includes a shunt reactor placed in the mid-cable with additional reactors at both ends of the cable, followed by an arrangement with reactors at the beginning and end. The GFM converter control maintained stability across all operating points, cable lengths, and configurations, whereas the stability of the GFL unit was highly dependent on active power injection and struggled under weaker grid conditions. Thus, for longer HVAC cables, it is necessary to employ GFM control units, and it is recommended to use shunt reactors at the cable start and end, as well as at mid-cable, for optimal stability.

This paper presents the findings from the initial phases of the SIF BLADE project, focused on demonstrating the capabilities of an offshore wind power plant (OWPP) for power system restoration (PSR). It provides an overview of PSR, highlighting its challenges and operational requirements, alongside the various scenarios considered in the project. The study includes a steady-state analysis to assess whether the OWPP can meet local network demands for both active and reactive power. Results indicate that the OWPP can operate within an envelope that covers all local power requirements. Additionally, EMT analysis were conducted to evaluate different percentages of grid-forming (GFM) converter penetration during the energization process. These analyses aimed to determine compliance with Transmission System Operator (TSO) requirements. Findings demonstrate that all GFM penetration levels met the necessary TSO standards. Furthermore, a novel small signal analysis was performed to identify the optimal percentage of GFM converters for enhancing system stability during block loading. The analysis suggests that for top-up scenarios, a GFM penetration between 20% to 40% is optimal, while for anchor scenarios, 40% to 60% GFM penetration enhances stability and robustness.

Offshore wind farms are increasingly being commissioned farther from shore, and high voltage alternating current (HVAC) transmission systems are preferred because of their maturity and reliability. However, as cable length increases, ensuring system stability becomes more challenging, making it essential to investigate shunt reactor compensation configurations and converter control strategies. This study examines three different shunt reactor compensation arrangements and two control strategies, grid-forming (GFM) and grid-following (GFL), across three cable lengths (80 km, 120 km, and 150 km). The systems were evaluated based on small-signal stability using disk margins for different active power operating points, and later for different short-circuit ratios (SCR) and X/R. The results demonstrate that the GFM is preferable for longer cables and enhanced stability. The most robust configuration includes a shunt reactor placed in the mid-cable with additional reactors at both ends of the cable, followed by an arrangement with reactors at the beginning and end. The GFM converter control maintained stability across all operating points, cable lengths, and configurations, whereas the stability of the GFL unit was highly dependent on active power injection and struggled under weaker grid conditions. Thus, for longer HVAC cables, it is necessary to employ GFM control units, and it is recommended to use shunt reactors at the cable start and end, as well as at mid-cable, for optimal stability.