HVDC Pole 2 Control System High Power Tests Completed

27 November 2013

Final high power tests on the new HVDC link were completed yesterday, with transfers of 1,195 MW being achieved (the link’s full capacity is 1,200 MW). 

Testing has been underway since January, and the final testing has involved proving a new, state of the art control system to run the full link. Attention now turns to re-running a small number of lower-power tests to verify some enhancements developed during testing. 

Transpower expects the new link to be fully available for commercial operation as early as next week. Meantime, the link will be made available to the market at up to 1,000 MW for northwards flow from tomorrow morning – close to its full capacity.

“It is a major milestone to complete the high power testing,” said Transpower Chief Executive Patrick Strange. “At these very high transfer rates, we cannot afford to have errors, since any failure will impact customers.”

Approximately 10 percent of North Island customers suffered a short outage on 12 November  when a high-powered HVDC test went wrong. “We deeply regret that interruption. However, it is why we have to test: the impact would have been far worse if it had occurred sometime during normal operation over the next twenty years.”

“We would like to acknowledge the support we have had from the generators and from many of our major customers – including the Tiwai smelter – through the long testing programme.”