Power Electronic Components and Electronic Converters Gave Birth to Numerous New
Applications, Offering Unmatched Comfort, Flexibility and Efficiency to the Customers. Owing to The
Improvement In Technologies, Large Number of Harmonics Are Introduced and They Degrade The
Performance of the Three-Phase Four-Wire Distribution System. These Effects of Distortion Also Affect The
Point of Common Coupling Where Other Loads Are Connected to the System. a Lot of Measures And
Mitigating Techniques Have Been Presented In the Literature But Each Has Its Own Drawbacks Like Circuit
Complexity, Lack of Reducing Lower Order Harmonics, Occurrence of Resonance Problems With Line
Impedance, Etc. to Overcome These Defects, the Thesis Proposes Two Techniques to Improve the Power
Quality of the System. the First Method Aims at Designing a Neutral Current Compensator and the Second
Method Involves Designing of Unified Power Quality Conditioner. the Neutral Conductor of Three-Phase
Four-Wire Distribution Systems Have Been Widely Employed to Deliver Electric Power to Single-Phase Or
Three-Phase Loads. the Neutral Conductor Usually Carries the Zero-Sequence Current Due to The
Unbalanced Loading Among Phase Conductors. As More and More Electronic Equipment Such As
Computers, Copy Machines and Adjustable Speed Drives Are Being Used, the Harmonic Currents Drawn By
Their Rectifier Front Ends Also Become Significant. Especially, the Zero-Sequence Triple (3Rd, 9Th, Etc)
Harmonics Accumulate In the Neutral ...