POWER QUALITY STUDIES
1.4 ( a ) Harmonic Studies:
A harmonic of a wave is a component frequency of the signal that is an integer multiple of the
fundamental frequency and a normal alternating current power system, the voltage varies
sinusoidal at a specific frequency, usually 50 or 60 hertz. When a linear electrical load is
connected to the system, it draws a sinusoidal current at the same frequency as the voltage
(though usually not in phase with the voltage).
This is primarily due to the rapid increase in non-linear, single-phase loads such as switched
mode power supplies, small fluorescent lighting ballasts, small uninterruptible power supplies
units and single- phase voltage controllers, along with the growth of transistor controlled
three-phase loads such as variable speed drives and large uninterruptible power supply units.
Together these comprise an ever-increasing portion of the total load of a typical industrial plant,
driven by the need to speed production and increase energy efficiency.
This is primarily due to the rapid increase in non-linear, single-phase loads such as switched
mode power supplies, small fluorescent lighting ballasts, small uninterruptible power supplies
units and single- phase voltage controllers, along with the growth of transistor controlled
three-phase loads such as variable speed drives and large uninterruptible power supply units.
Together these comprise an ever-increasing portion of the total load of a typical industrial plant,
driven by the need to speed production and increase energy efficiency.
One of the major effects of power system harmonics is to increase the current in the system.
This is particularly the case for the third harmonic, which causes a sharp increase in the zero
sequence current, and therefore increases the current in the neutral conductor.
With the help of latest power and harmonic portable meters our experts will be able to correctly
determine the harmonics up to any order in the system.The expert recommendations will be
available for suppressing the harmonics and design of suitable filters.
One of the major
effects of power
system harmonics
is to increase the
current in the
system.
ENERGY/POWER QUALITY/SAFETY AND ENVIRONMENT SOLUTIONS
07
PROLIANCE ENERGY SOLUTIONS
Fundamental Frequency f
First harmonic 2f
Second harmonic 3f
Common note
