It will supply 32 of its N117/3600 turbines, having already received an order for 50 units of the same model last year.
The expansion brings the total capacity of the 82-turbine Wieringermeer to 295.2MW.
Preparatory work for the installation of the first 50 turbines is under way, Nordex stated, with commissioning planned for 2019. Once the first phase is completed, the additional 32 turbines will be installed, it added.
Nordex and Vattenfall signed the turbine purchase agreement at the Global Wind Summit in Hamburg, Germany.
Vattenfall will sell all of the 180MW first phase's output to US technology giant Microsoft, under a ten-year power purchase agreement (PPA) signed in November 2017.