A NOVEL CONTROL SCHEME FOR FAST AND EFFECTIVE CONTROL OF

DYNAMIC VOLTAGE RESTORERProject Progress Report

ByBhargava lakshmi SReg.No:10021D0802

Electrical and Electronics EngineeringHigh Voltage Engineering

College of EngineeringJNT University, Kakinada.

Under the Esteemed Guidance ofSmt.N. Sumathi

Asst Professor/EEEJNT University, Kakinada

PROJECT REPORT: MODULE1Module

No.ModuleName.

Objectives WorkStatus

Module IDEC-FEB Literature Survey

To know the DVR device Different controllers that can be used with DVR to mitigate voltage sags

completed

Module IIFEB-MAY

Designing

Parameters for LES digital filters Parameters for phasor based load voltage control system

In progress

Module IIIMAY-JUL

SimulationWork

Sag compensation with linear andnon linear load conditions

Incomplete

PROJECT REPORT: MODULE2 Module

No.ModuleName.

Objectives WorkStatus

Module IDEC-FEB Literature Survey

To know the DVR device Different controllers that can be used with DVR to mitigate voltage sags

completed

Module IIFEB-MAY

Designing

Parameters for LES digital filters Parameters for phasor based load voltage control systemSag compensation with linear load conditions

completed

Module IIIMAY-JUL

SimulationWork

Sag compensation with linear andnon linear load conditions

In progress

INTRODUCTION

The wide spread use of electronic equipment, has made the loads to become more sensitive and less tolerant to short term disturbances in the form of voltage sags.

A dynamic voltage restorer can eliminate most sags and minimize the risk of load tripping during sags.

It injects appropriate three phase ac voltages in series with the supply when a point of common coupling (PCC) voltage sag is detected

If a voltage sag exceeds even two or three cycles it may cause heavy production and quality losses

So it is necessary that the DVR should be fast and effective in mitigating voltage sags

Objective

The objective is to compensate balanced and unbalanced voltage sags in a three phase power system network under linear and non linear load conditions in a very short time period with out phase jump using the dynamic voltage restorer.

Proposed Solution

A fast and effective control scheme for the Dynamic Voltage Restorer is proposed in this project.

Three identical control systems are used to control the injected voltage in each phase independently

The proposed multiloop control system is comprised of an outer phasor based load voltage control system and an inner injected voltage control system.

The phasor parameters of the measured supply and load voltages are estimated by using least error square filters

SCHEMATIC DIAGRAM OF THE DVR WITH LINE SIDE HARMONIC FILTER

BLOCK DIAGRAM OF THE DVR CONTROL SYSTEM FOR EACH PHASE

SIMULINK MODEL OF POWER CIRCUIT OF GIVEN NETWORK

SIMULINK MODEL FOR CONTROL CIRCUIT

SUBSYSTEM OF DVR

SIMULINK MODEL FOR MEASUREMENT BLOCK

THREE PHASE SUPPLY VOLTAGES DURING LL FAULT

INJECTED VOLTAGE FOR DEPRESSED PHASES

ESTIMATED THREE PHASE SUPPLY VOLTAGES

DC-Link Voltage

RESTORED LOAD VOLTAGES

THREE PHASE SUPPLY VOLTAGES DURING LG FAULT

INJECTED VOLTAGE FOR DEPRESSED PHASES

ESTIMATED THREE PHASE SUPPLY VOLTAGES

DC-Link Voltage

RESTORED LOAD VOLTAGES

REFERENCES1. Firouz Badrkhaniajaei, Saeed Alirezanad Farhangi “A Fast And Effective Control

Scheme For the Dynamic Voltage Restorer.”2. S.M. Vilathgamuva, H.m. Wijeckoon, and S.S. Choi, “A Novel control Technique to

compensate voltage sags in multiline distribution system- The interline dynamic voltage restorer”

3. H. Awad,J.Sevensson, and M. Bollen. “Mitigation of unbalanced voltage dips using static series compensator”

4. B. Delfino, F. Fornari, and R. Procopio, “An effective SSC control scheme for voltage sag compensation,” IEEE Trans. Power Del., vol.20, no. 3, pp. 2100–2107, Jul. 2005.

5. J. G. Nielsen, F. Blaabjerg, and N. Mohan, “Control strategies for dynamic voltage restorer compensating voltage sags with phase jump,” in Proc. IEEE APEC, 2001, pp. 1267–1273.

6. S. S. Choi, J. D. Li, and D. M. Vilathgamuwa, “A generalized voltage compensation strategy for mitigating the impacts of voltage sags/swells,” IEEE Trans. Power Del., vol. 20, no. 3, pp. 2289–2297, Jul. 2005.

THANK YOU