1. POWER QUALITY
G.Sowmya
Email id: sowmyareddy0216@gmail.com
Phone number: 7842495978
ABSTRACT
 Introduction:
Power quality is simply the interaction of electrical power with electrical
equipment. If electrical equipment operates correctly and reliably without being damaged or
stressed, we would say that the electrical power is of good quality. On the other hand, if the
electrical equipment malfunctions, is unreliable, or is damaged during normal usage, we
would suspect that the power quality is poor.
Power quality issues can be high-speed events such as voltage impulses /
transients, high frequency noise, wave shape faults, voltage swells and sags and total power
loss. Ideally, the best electrical supply would be a constant magnitude and frequency
sinusoidal voltage waveform.
The quality of electrical power may be described as a set of values of parameters,
such as:
 Continuity of service
 Variation in voltage magnitude
 Transient voltages and currents
 Harmonic content in the waveforms for AC power
 Importance of power quality improvement:
If the Power Quality of the network is good, then any loads connected to it will
run satisfactory and efficiently. Installation running costs and carbon footprint will be
minimal. If the Power Quality of the network is bad, then loads connected to it will fail or will
have a reduced lifetime, and the efficiency of the electrical installation will reduce.
 Causes and effects:
 Black outs
 Brown outs
 Voltage sag
 Interruptions
 Voltage spikes

2.  Voltage swell
 Harmonic distortion
 Voltage surges
 Flickering
 Voltage fluctuation
 Noise
 Voltage unbalance
 Mitigation techniques:
 Dynamic voltage restorer
 Sag detection techniques
 Control techniques
 Harmonic filters
 Distribution Static compensators
 Constant voltage transformers
 Isolation transformers
 Transient voltage surge suppressors
 Noise filters
 Static VAR compensators
 Unified power quality conditioning
 Impacts on environment and society