wgD3ImpactDR - Impact of Distributed Resources on...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Impact of Distributed Resources on Distribution Relay Protection A report to the Line Protection Subcommittee of the Power System Relay Committee of The IEEE Power Engineering Society prepared by working group D3 Abstract This report covers how the addition of distributed resources will impact the distribution relay protection of the system. The issues covered include protective device coordination problems due to infeed and bi- directional current flow; effects on synchronizing and autoreclosing; the potential for forming small islanded systems; and issues related to ground fault detection. The types of interface transformer connections are compared. Their influence on the protection of the system is based on the type of connections. Changes to relay protection in response to the problems encountered and other solutions that have been applied are also covered. The protection of the generators and the interface protection are specifically omitted from this report. Some issues related to control of voltage levels and capacitor switching are included. Members of the working group Tony Seegers – chair Ken Birt – vice-chair Ron Beazer Miroslav Begovic Ken Behrendt Steve Boutilier Raluca Lascu Patrick Carroll Al Darlington Wayne Hartmann Rich Hunt Gerald Johnson Ali Kazemi Ljubomir Kojovic Dean Miller Pratap Mysore Bob Pettigrew Don Sevcik Charles Sufana S.S. Venkata Ron Westfall August 2004
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
CONTENTS Introduction. .................................................................................................................................... 1 1 Types of Distributed Resources and History . ......................................................................... 1 2 DR Interface Transformer Connections. ................................................................................. 2 2.1 High Side Delta or Ungrounded Wye. ............................................................................ 3 2.2 Low Side Delta . .............................................................................................................. 4 2.3 Wye-wye. ........................................................................................................................ 5 3 Possibility of Ungrounded Systems. ....................................................................................... 6 3.1 Generation with ungrounded transformer primary windings. ......................................... 6 3.2 Loss of primary source to substation power transformer. ............................................... 7 3.2.1 Islanded Operation. ................................................................................................. 7 3.2.2 Protection for High Side Faults. .............................................................................. 8 3.2.3 Requirements for Line Protection at the Utility Substation. ................................... 8 3.2.4 System Overvoltage Issues . .................................................................................... 8 3.2.5 Other Issues. ............................................................................................................ 8 4 Fault Current from Distributed Resources. ............................................................................. 8 4.1 Increased Duty . ............................................................................................................... 9 4.2 Direction of Power Flow. ................................................................................................ 9 5 Effects on Relay Application and Settings . ............................................................................ 9 5.1 Coordination Problems . .................................................................................................. 9 5.1.1 Relay, Fuse, and Line Recloser. ............................................................................ 10 5.1.2 Impact on fuses saving schemes . .......................................................................... 12 5.1.3 Sensitivity & Clearing Times. ............................................................................... 15 5.1.3.1 Grounded DR Interconnection. ......................................................................... 15 5.1.3.2 Ungrounded DR Connections. .......................................................................... 17 5.2 Need and Availability of Communications Circuits. .................................................... 17 5.2.1 Transfer Trip Signals . ........................................................................................... 18 5.2.2 Operating Status. ................................................................................................... 18 5.2.3 Communication Medium . ..................................................................................... 18 6 Safety Concerns . ................................................................................................................... 18 7 Voltage Issues. ...................................................................................................................... 20 7.1 Line Drop Compensation. ............................................................................................. 20 7.2 Switched Capacitors. ..................................................................................................... 20 7.2.1 Timed Capacitor Banks: . ...................................................................................... 20 7.2.2 Voltage Controlled Capacitor Banks:. .................................................................. 21 7.3 Ferroresonance. ............................................................................................................. 21 8 Load Shedding Issues . .......................................................................................................... 22 8.1 Underfrequency Load Shedding . .................................................................................. 22 8.2 Undervoltage Load Shedding . ...................................................................................... 23 9 Breaker Closing . ................................................................................................................... 23 9.1 Need for Synch Check or Dead Voltage Closing . ........................................................ 23 9.2 Effect on Substation Reclosing Practices . .................................................................... 24 References. .................................................................................................................................... 24 Bibliography . ................................................................................................................................ 24 This is a special report of the IEEE – Power System Relay Committee
Background image of page 2
Introduction The use of distributed resources has increased substantially since 1998 because of the potential to provide increased reliability and lower cost of power delivery to customers.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 26

wgD3ImpactDR - Impact of Distributed Resources on...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online