Senvion will supply 32 of its 6.2M152 turbines with a power upgrade, and will service them when they become operational in autumn 2019.
The company's 6.2M126 turbines are currently being installed at the 111MW Nordergunde project, but this is the first order for the longer-bladed model.
Senvion CEO Jürgen Geissinger said the contract confirmed the company was "setting standards in the cost-effective generation of offshore wind energy", and that it would "further consolidate our strong position in the offshore wind-energy market".
The Trianel Windpark Borkum ll is planned for a site in the North Sea, 45 kilometres north of the island of Borkum. A final investment decision is expected in the first half of 2017, with construction starting in early 2018.
The first 200MW phase comprises 40 Adwen M5000-116 turbines and came online in 2015.