A PWM CONTROLLED SYNCHRONOUS LINK CONVERTER SCHEME FOR POWER QUALITY IMPROVEMENT AT NONLINEAR LOAD

A PWM CONTROLLED

SYNCHRONOUS LINK CONVERTER

SCHEME FOR POWER QUALITY

IMPROVEMENT AT NONLINEAR

LOAD

GARIMA GOSWAMI

Asst. Proffessor ,Electrical &Electronics Engg.Deptt , AEC, AGRA, MTU, NOIDA, U.P

[email protected]

PANKAJ KUMAR GOSWAMI

Asst. Proffessor ,Electronics & Communication Engg.Deptt , HCST, Mathura, MTU, NOIDA, U.P

[email protected]

Abstract :

The harmonics generated by nonlinear load when added with reactive load causes more problematic to supply system as it not only affects transformer at supply end, but also to other consumers connected to same supply. Because of these problems, the power quality is an issue and an object of great concern not only for consumers but also for distributors

.

This paper presents modeling and simulation of a Synchronous Link Converter (SLC) using PWM connected to a single-phase system having both reactive and non-linear load. The SLC acts as Active Power Filter for harmonics compensation and static Synchronous Compensator for variable compensation of load. The proposed model is designed and simulated using MATLAB/Simulink. The relevant results are presented for justifications.

Keywords:

SLC; Active Filters; Harmonics Compensation; Power Quality; MATLAB/SIMULINK;

1. Introduction

Fig. 1 Parallel converter scheme

2.1.Power quality Analysis with Linear load Application

Fig. 2 linear load model

2.1.1 Simulation results at linear load

Fig. 3 Source voltage

Fig. 4 Load current

2.2.Power quality Analysis with Non Linear load Application

2.2.1 Simulation results at non linear load

Fig. 6 source voltage

Fig 7 Harmonic distortion in line current at non linear load

2.3.Power Quality Improvement on Nonlinear Load using SLC with PWM control

Fig. 8 Simulink Model of Proposed Harmonic Reduction scheme

2.3.1 Simuation Results of Proposed Scheme

Fig 9 source voltage at proposed model

Table 1: Comparative analysis of power quality improvement Applied voltage (peak value) (Vs) Source current (peak value) (Is)

Load THD

(%) R (ohm) L (mH) Non linear load With linear load

311.13v 3.2 A with out distortion

200 1 _____ Less

than 1 % With non

linear load

311.13v Appx 3.2 A with distortions

200 1 Thyristor Bridge converter 117% With non linear load using SLC

311.13v 3.2 A with very reduced THD

200 1 Thyristor Bridge converter In parallel with

SLC

17%

3. Conclusion:

References

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[2] Prof. Mack Grady “Understanding Power System Harmonics” by Dept. of Electrical & ComputerEngineering University of Texas at Austin. www.ece.utexas.edu/~grady

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