FLEXIBLE AC TRANSMISSION SYSTEMS important questions

EE2036 FLEXIBLE AC TRANSMISSION SYSTEMS SYLLABUS

AIM: To enhance the transmission capability of transmission system by shunt and

series compensation using static controllers.

OBJECTIVES:

· To understand the concept of flexible AC transmission and the associated problems.

· To review the static devices for series and shunt control.

· To study the operation of controllers for enhancing the transmission capability.

UNIT I INTRODUCTION

The concept of flexible AC transmission - reactive power control in electrical power

transmission lines -uncompensated transmission line – series and shunt compensation.

Overview of FACTS devices - Static Var Compensator (SVC) – Thyristor Switched

Series capacitor (TCSC) – Unified Power Flow controller (UPFC) - Integrated Power

Flow Controller (IPFC).

UNIT II STATIC VAR COMPENSATOR (SVC) AND APPLICATIONS

Voltage control by SVC – advantages of slope in dynamic characteristics – influence of

SVC on system voltage. Applications - enhancement of transient stability – steady state

power transfer – enhancement of power system damping – prevention of voltage

instability.

UNIT III THYRISTOR CONTROLLED SERIES CAPACITOR(TCSC)AND

APPLICATIONS

Operation of the TCSC - different modes of operation – modeling of TCSC – variable

reactance model – modeling for stability studies. Applications - improvement of the

system stability limit – enhancement of system damping – voltage collapse prevention.

UNIT IV EMERGING FACTS CONTROLLERS

Static Synchronous Compensator (STATCOM) – operating principle – V-I characteristics

– Unified Power Flow Controller (UPFC) – Principle of operation - modes of operation –

applications – modeling of UPFC for power flow studies.

UNIT V CO-ORDINATION OF FACTS CONTROLLERS

FACTs Controller interactions – SVC–SVC interaction - co-ordination of multiple

controllers using linear control techniques – Quantitative treatment of control

coordination.

TEXT BOOK:

1. Mohan Mathur, R., Rajiv. K. Varma, “Thyristor – Based Facts Controllers for Electrical

Transmission Systems”, IEEE press and John Wiley & Sons, Inc.

REFERENCES:

1. A.T.John, “Flexible AC Transmission System”, Institution of Electrical and Electronic

Engineers (IEEE), 1999.

2. Narain G.Hingorani, Laszio. Gyugyl, “Understanding FACTS Concepts and

Technology of Flexible AC Transmission System”, Standard Publishers, Delhi 2001.

IMPORTANT QUESTIONS

1.Explain the various basic types of FACTS controllers 2.Explain the working and characteristic of Thyristor Switched Series

3.Explain the reactive power compensation at the sending, midpoint and receiving ends of the transmission lines

4.Explain the operation of UPFC with vector diagrams

5.Discuss the different advantages of slope in dynamic characteristics of SVC

6.Explain about the performance of SVC in controlling voltage in a power system

7.Explain the different applications of TCSC

8.Briefly describe the way by which the transient stability is enhanced due to Static VAR

9.explain the different modes of operation of TCSC,With a neat block diagram

10.Explain the principle of operation and VI characteristics of STATCOM with neat sketch

11.Explain the basic operating principle and the control capability of UPFC

12.Explain the operation of STATCOM with an aid of block diagram.

13.Explain the basic operating principle and the control capability of UPFC

14.Discuss the coordination procedure of multiple controllers using linear control techniques in detail

15.Discuss Linear quadratic regulator based techniques, Global coordination using nonlinear constrained optimization, Control coordination using genetic algorithms.

16.Explain in detail about SVC-SVC interaction.