Quiz: Workshop 02

Blackout is;

• A fault

• Total failure of the power system

• Solar eclipse

• Power cut period

System frequency is maintained at 50 Hz by;

• Generators by changing their excitation

• Consumers by switching off some of their loads

• System operator making sure that generation is equal to demand all the time

• None of the above

What happened on 26^th Feb 2016 in Sri Lankan power system?

• Disconnection of two critical 132 kV lines

• Disconnection of two critical 220kV lines

• It was a rainy day but power system was working as usual

• There was a blackout created by supply-demand unbalance

Out of Step relay measures;

• Fault current

• Fault voltage

• Impedance to the fault

• None of the above

On the R-X plane, the operating point is closer to the origin;

• When there is a fault

• All the time

• Under normal operating condition

• During a blackout

To determine the appropriate setting for an out-of-step relay;

• Need to wait till a few blackouts

• Transient stability studies should be carried out

• A comprehensive fault study should be carried out

• Collect PMU data from many substations

Out-of-step event is classified as;

• A wide-area event

• A local event

• A faulty event

• None of the above

PMU data is not used for;

• Power system state estimation

• Power system monitoring and warning

• Power system event analysis

• Demand management

A cause of a transmission line tripping is;

• Easy to identify

• Not possible to identify

• Difficult to identify

• Always known

In Sri Lanka PMUs are installed;

• In all transmission lines

• Only in Biyagama – Kotmale line

• Only in Kotmale substation

• Only in Biyagama substation