This document discusses power quality and how to improve it in power systems. It defines power quality and explains why it is important for limiting lost production and equipment damage. It then outlines common power quality defects like voltage fluctuations, transients, and harmonics. Some sources of poor power quality are identified as non-linear loads, switching operations, reactive loads, and atmospheric conditions. Finally, it discusses solutions like surge suppressors and isolation transformers and concludes by stressing the need to monitor harmonics and penalize sources that exceed limits.

1. JABALPUR ENGINEERING COLLEGE
ELECTRICAL ENGINEERING DEPARTMENT
POWER QUALITY IMPROVEMENT
IN POWER SYSTEM
Presented By
Mr. Pratyush Kumar Singh
0201EE21ME21
Under the guidance of
Sudeep Mohaney
Assistant Professor

2. CONTENTS
 INTRODUCTION
 WHY POWER QUALITY IS IMPORTANT
 SPECIFICATION OF THE GOOD POWER
QUALITY
 POWER QUALITY DEFECTS
 SOURCE OF POOR POWER QUALITY
 SOLUTION OF THE POOR POWER QUALITY
 CONCLUSION

3. INTRODUCTION
Power Quality is defined as the degree to which the power
supply approaches the ideal case of stable, uninterrupted, zero
destruction, and disturbance-free supply.
Power Quality is the combination of voltage profile, Frequency
profile, Harmonics contains, and reliability of power supply.
The power quality problem is defined as any problem
manifested in voltage, current, or frequency deviations that
results in the mal-operation of customer equipment.
PQ mainly deals with
 Continuity of the supply.
 “Quality” of the Voltage.

4. WHY POWER QUALITY IS IMPORTANT
 LOST PRODUCTION: Each time production is interrupted, your
business loses the margin on the product that is not manufactured
and sold.
 DAMAGED PRODUCT: Interruptions can damage a partially
complete product, and cause the items to be rerun or scrapped.
 MAINTENANCE: Reacting to a voltage disruption can involve
restoring production, diagnosing and correcting the problem,
cleaning up and repairing, disposing of damaged products, and, in
some cases, environmental costs.
 HIDDEN COSTS: If the impact of voltage sag is a control error, a
product defect may be discovered after customer delivery. The costs
of losing repeat sales, product recalls and negative public relations
can be significant and hard to quantify.

5. THE GOOD QUALITY OF POWER CAN BE SPECIFIED AS
 The supply voltage should be within the guaranteed
tolerance of the declared value.
 The waveshape should be a pure sine wave within
allowable limits for distortion.
 The voltage should be balanced in all three phases.
 Supply should be reliable i.e. continuous availability
without interruption

6. POWER QUALITY DEFECTS
 Variations in voltage, magnitude, and
frequency.
 Variations in frequency can rise out
of system dynamics or harmonics
injection.
Power Quality Defects
 Voltage Fluctuations
 Transient
 Harmonics

7. VOLTAGE FLUCTUATIONS
Voltage fluctuations are changes or swings in the
steady-state voltage above or below the designated
input range for a piece of equipment. Fluctuations
include both sags and swells.

8. TRANSIENT
Transients, commonly called "surges," are sub-cycle
disturbances of very short duration that vary greatly
in magnitude.

9. HARMONICS
The dynamic power system loads produce a time-varying
amplitude in current waveforms depending on the load
characteristics which consists of the fundamental and
harmonics components.
 For assessing power quality it is important to know the
total harmonic distortion i.e. the voltage and current
distortion factors

10. SOURCE OF POOR POWER QUALITY
 NON-LINEAR LOADS
 SWITCHING OPERATION
 REACTIVE LOADS
 ATMOSPHERIC CONDITION
 UNSTABLE LOADS

11. SOLUTION TO THE POOR POWER QUALITY
 SURGE SUPPRESSORS: These are
small plug-in devices designed to protect
equipment from moderate surges and
spikes.
 ISOLATION TRANSFORMERS:
These devices electrically separate the
electronic equipment from the incoming
power system, reducing unwanted
electrical noise.

12. CONCLUSION
Harmonic distortion is increasing day by day at a faster rate and is a
matter of concern to the utility, customers, and manufacturers of
different equipment.
 In India it is necessary first to create awareness regarding harmonic
problems, their effects, and elimination techniques among the utility,
consumers, and manufacturers of different equipment to make
power systems less polluted.
 The utility should monitor the installation of high-tension consumers
periodically, regarding the harmonic distortion and penalties should
be imposed on customers using equipment crossing specified limits.