The wind industry is driven by constant pressure for efficiency. Increasingly, wind farm operators are therefore opting for an increased voltage level of 66 kV instead of the previous 33 kV. If the total voltage level of wind farms is raised to 66 kV, a large part of the costs for the energy infrastructure can be saved. The size and number of transformer platforms on the high seas can be significantly reduced, which at the same time reduces the amount of lines needed. Added to this are lower maintenance and repair costs. With the construction of offshore wind farms with a capacity of 2 GW and the switch to the 66 kV direct connection, the TSOs are placing new demands on the integration of the wind farms. What are the new requirements for the voltage-forming behaviour and the provision of models for the precise characterisation of the electrical behaviour?