TenneT Connects North Sea Wind Farms with Crucial Testing by KEMA

TenneT and its subcontractors have achieved a momentous milestone with the successful completion of a cutting-edge transformer substation in Wijk aan Zee. This groundbreaking facility integrates three new North Sea wind farms into the Netherlands’ high-voltage network, comprising the Hollandse Kust Noord land station and the Wijk aan Zee 380kV substation. The substation’s core components are the land station, converting green electricity from the wind farms from 220kV to 380kV, and the substation, expertly directing power to various customers, including Tata Steel, and integrating it into the national 380 KV grid via the Beverwijk substation.

KEMA Labs conducted meticulous release tests on behalf of TenneT’s contractors, assessing the substation for the occurrence of Corona—crackling discharges near high-voltage electrical installations. The extensive assessment, spanning several weeks in an area equivalent to 23 football fields, utilized specialized cameras to detect air discharges, enabling prompt resolution of any identified issues. Additionally, KEMA Labs carried out critical high voltage tests on 12 circuits, using multiple Series Resonant test sets. This demanding setup, requiring two days to assemble, allowed testing at a voltage 1.7 times higher than the cables’ operational voltage, efficiently detecting any manufacturing or assembly faults.

Looking ahead, the project faces its final significant challenge in November—a 69km long submarine cable test to the wind farm park using five test sets. Intensive coordination between KEMA Labs and TenneT ensures smooth execution within the set timeframe, addressing safety concerns related to high voltage tests, construction activities, and on-site transport .

Despite the project’s complexity, all tests were executed flawlessly as planned, with several cable circuits now operational. KEMA Labs remains committed to future collaborations, as TenneT paves the way for innovative and sustainable projects ahead.