Project: Upper Island Reactive Power Study
Country: New Zealand
Year: September 2012 - January 2013
Transpower is planning to install a Reactive Power Controller (RPC) in their Upper North Island (UNI), with the goal of maintaining steady state 220kV and 110kV voltages according to setpoints, as well as sufficient reactive power reserves in the area. A similar such RPC exists in the Southern Island near Christchurch. The purpose of the RPC studies was to see if this RPC design could work in such a tightly coupled system, and if so, how it would be best configured with the equipment available to be controlled, including generators, several STATCOMs, switched capacitors and transformers with on-load tap-changers.
This was a very technically challenging (and interesting) project. It was not a simple task to get the quasi-steady state simulator to work well with the RPC, and then to come up with a design and suggestions as to how to ensure the RPC properly utilized all of the available reactive power sources, while maintaining system voltages within limits and while maintaining reactive power reserves within limits. But in the end, the project was a success, and everyone involved in the project learned a lot.