The Effects of Harmonics on Capacitors
include additional heating - and in severe cases overloading, increased
dielectric or voltage stress, and unwanted losses. Also, the combination of harmonics
and capacitors in a system could lead to a more severe power quality condition called
harmonic resonance, which has the potential for extensive damage. Consequently,
these negative effects will shorten capacitor life.
Power Quality In Electrical Systems
A compilation of various power quality information, issues, applications, technologies, news and updates
STATIC SYNCHRONOUS SERIES COMPENSATOR (SSSC)
Thursday, May 31, 2012
Static Synchronous Series Compensator
(SSSC) is a modern power quality FACTS device that employs a voltage source converter
connected in series to a transmission line through a transformer. The SSSC
operates like a controllable series capacitor and series inductor. The primary
difference is that its injected voltage is not related to the line intensity
and can be managed independently. This feature allows the SSSC to work
satisfactorily with high loads as well as with lower loads.
FERRORESONANCE PREVENTION TUTORIALS
Monday, April 30, 2012
Ferroresonance Prevention Tutorials
deal with strategies that electric utilities and end-users could implement to
minimize occurrence of the power quality phenomenon. These practices are based
from the fact that ferroresonance usually happens with lightly loaded three-phase
transformer, having one or two phases open either intentionally or accidentally. Common strategies for managing ferroresonance
include: Preventing open phase condition, limiting overvoltages, damping
resonance with secondary load, limiting cable length, switching at transformer terminals
and grounding transformer primary.
FERRORESONANCE AND TRANSFORMER CONNECTIONS
Saturday, March 24, 2012
Ferroresonance and Transformer Connections
are related as such that the latter is a significant factor to the occurrence
of the former during loss of phase or open phase conditions. There are certain transformer
configurations that are more susceptible to ferroresonance. Generally, ferroresonance
phenomenon becomes highly probable if the primary windings of the three-phase
transformer are ungrounded.
POWER QUALITY BASICS: FERRORESONANCE
Wednesday, February 29, 2012
Ferroresonance is usually described as
an irregular and chaotic type of resonance. This phenomenon occurs because of
the nonlinear characteristic of iron-core (saturable) inductors - ferromagnetic
material such as a transformer. Ferroresonance is often times associated with
unwanted and destructive overvoltages, but has found some helpful applications
in Constant Voltage Transformers, which can mitigate power quality problems
like voltage sags.
POWER QUALITY BASICS: VOLTAGE NOTCHING
Sunday, January 29, 2012
Voltage Notching is described by IEEE
as a recurring power quality disturbance due to the normal operation of power
electronic devices (i.e. rectifier), when current is commutated from one phase
to another. Conventionally, the current waveform is used as the starting point
for harmonic analysis, and voltage notching is simply derived from the IZ drops
of the harmonic currents.
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About Me

- yepyep
- I am a Professional Electrical Engineer with a Masters Degree in Business Administration. My interest is in Power Quality, Diagnostic Testing and Protective Relaying. I have been working in an electric distribution utility for more than a decade. I handle PQ studies, power system analysis, diagnostic testing, protective relaying and capital budgeting for company projects.