The North Auckland and Northland (NAaN) project reached a major milestone last week when the new 220 kV cable circuit between Albany and Wairau Road substations passed its High Voltage AC test (HVAC).
Over the last 18 months, approximately 8.4 kilometres of cable circuit has been installed between the two substations, including along the Northern Busway and through the residential parks and businesses across the North Shore Transmission Corridor.
It is the first of the four cable sections between Pakuranga and Albany to be installed and tested.
Prior to this live testing, the cables had already passed a series of rigorous checks including factory acceptance testing and sheath testing during installation.
The HVAC test with simultaneous Partial Discharge Monitoring ensures the 12 joints along its 8.4 km length and the terminations at Albany and Wairau Road are ready for connection to the grid. It involved setting up an HV Test set at Albany and visiting each joint along the cable route to install High Frequency Current Transducers and Omicron electronics at each link box. Tests were then carried out across the cable at high voltage to ensure joints and terminations were secure.
Project Manager Shaun Frazerhurst commended the efforts by Nexans Olex, Electrix, Transfield, Downer, Omicron and all others involved in test preparation as well as the installation works.
“This has been a challenging project and the team has worked well together to achieve this great result.
“We were extremely mindful of the impact our work could have on residents, motorists and public transport networks and worked with a number of agencies to minimise the effects where possible.”
Installation of the second cable circuit between the Wairau Road and Hobson Street substations is progressing well with HVAC testing expected to get underway in August and commissioning with the Hobson Street GXP.
Commissioning of this cable circuit is expected to take place in May.