HVDC Power - Fast Reaction Emergency Dump System

Cook Strait is a wild stretch of sea that separates the North and South Islands of New Zealand.  At its narrowest it is 22km (18 miles) and joins the Tasman Sea and Pacific Ocean between the main islands.  With a high average rainfall in the South Island most Power Generation takes place there with demand coming from the higher population base in the North Island. 

With the upgrading of the Cook Strait HVDC cable, Abbey Systems won the contract to provide a Fast Reaction Emergency Dump system to protect the southern-based generation.  The system is designed to shed load in the North Island if a fault develops within the cable.  A load shedding initiation command would be broadcast to all interruptible load consumers within 0.5 second of detection of a fault in the cable.  Loads in the North Island will be shed automatically in accordance with the severity of the fault, local consumers' conditions and the specific shedding configurations prescribed by the Control System Operator.
The Control Systems Operator has available the following control and monitoring using Abbey Systems Powerlink software and RTU hardware.
  • Monitor total load and load available for shedding
  • Inhibit a specific load from being shed
  • Manually shed remote load
  • Manually restore remote load
  • Receive and Acknowledge alarms
 
  ".....the Abbey Systems equipment was chosen from a range of telemetry equipment available in New Zealand.  Abbey Systems were the only supplier able to meet the stringent requirement of propagating the "shed" command to users within 0.5 second.  System robustness and reliability were other contributing factors to Abbey Systems being awarded the contract"

                Alasdair Turner
                Transpower Senior Engineer