Transformer failure causing power blackouts

POWER outages in Port Moresby recently were caused by a failure in the Waigani substation distribution transformer, according to PNG Power Ltd.
Managing director Flagon Bekker said the failure was probably caused by excessive tap-changing cycles.
“Our technical teams are currently working on site to replace the transformer at the Waigani substation, therefore we will be rationing power supply from the substation,” he said in a statement.
“The tap-changer is a critical part inside a transformer of this type – like a gear box in your car.”
He said transformers for power systems were expensive.
“With over 750 power transformers in Port Moresby ranging from K50,000 to K500,000 in cost, it is difficult to prioritise which piece of equipment gets rehabilitated.”
He said Port Moresby, on Monday, experienced a total power outage on its grid at 5am.
“Our maintenance crews immediately kick-started the restoration process while also identifying the fault to be at our Waigani substation.
“Most parts of the city were eventually restored by 9am,” he said.
“To remove, inspect, repair or replace this internal mechanism takes time.
“While this key transformer is out of action, it weakens the flexibility of the grid leading to the requirement for load shedding and associated mitigation actions.
“We are working around the clock on this and expect this to last the rest of the week.
“To continue to supply you with energy, we are working around this by re-directing energy under our normal protocol and procedures.”