II. Types of Power Quality Problems and Their Cause-Effects

Voltage Sags

Capacitor Switching Transients

Harmonics

Lightning Transients

High Impedance Faults

Voltage Sags

Major causes: faults, starting of large loads, and brown-out recovery.
Major consequences: shorts, accelerated aging, loss of data or stability, process interrupt, etc.

Major causes: a power factor correction method
Major consequences: insulation breakdown or sparkover, semiconductor device damage, shorts, accelerated aging, loss of data or stability

Major causes: power electronic equipment, arcing, transformer saturation.
Major consequences: equipment overheating, high voltage/current, protective device operations.

Major causes: lightning strikes
Major consequences: insulation breakdown or sparkover, semiconductor device damage, shorts, accelerated aging, loss of data or stability

(One of the most difficult power system protection problems)
Major causes: fallen conductors, trees (fail to establish a permanent return path)
Major consequences: fire, threats to personal safety