Peter Hofmann Chief Engineer-Distribution Engineering Consolidated Edison, New York PQView User Group Meeting New York, NY August 31 – September 02, 2010

Peter HofmannChief Engineer-Distribution EngineeringConsolidated Edison, New York

PQView User Group MeetingNew York, NYAugust 31 – September 02, 2010

Update on PQView’s Roleat Con Edison in New York City

2© 2010 Electrotek Concepts, Inc. All rights reserved.

27,13, 4 kV

13 kV

27, 4 kV

33,13, 4 kV

Distribution System 62 Distribution Substations 83 Secondary Networks, and

Non-network load pockets 2,247 Distribution Feeders

87% System is underground

New York City & Westchester

3.3 million electric customers

System peak load 13141 MW


Overview of Con EdisonPower Delivery System


PQ Monitoring for Smart Distributionat Con Edison

•Area Substations Transformers– Power quality monitors

•Secondary Networks– Power quality monitors– Network Transformer RMS

Network Distribution Feeders– Microprocessor relays

•Area Substations Capacitors– Microprocessor relays

•Unit Substation Transformers– Power Quality Monitoring and

Phasor Measurement Sensors

•High Tension Remote Monitoring– Power and power quality

monitoring•Customer Smart Meters

– Energy and power quality•Distribution and Transmission

SCADA– Automatic momentary

interruption analysis and correction with IEDs


Con Edison Monitoring System

Area Substation Transformers•Supply the Con Edison distribution network feeders. •Each substation has at least one power quality monitor at the

output of one transformer.•Many area substations have more than one transformer

monitored to allow for redundancy in the automatic fault location system and other analysis tools.



Network Distribution Feeders•The network feeders supply underground network customers in

which each feeder supplies transformers that in turn supply a low voltage distributed secondary network.

•The network feeders are protected using overcurrent relays. Today, about 800 microprocessor relays on feeder and bus breakers are monitored.– feeder energizing– breaker trip events due

to faults – short-duration overcurrent

events due to incipientfaults.



Area Substation Capacitors• Con Edison has developed an automatic capacitor health analysis system

– Automatic correlation with SCADA operations– Abnormal switching transients (e.g., restrike or magnification)– Unbalanced reactive power changes

• Con Edison intends to increasethe number of distributioncapacitors monitoredwith power quality monitorsand with microprocessor relaysover the next three years.



Unit Substation Transformers•The unit substation transformers supply Con Edison’s overhead

distribution feeders system. •There are few power quality monitoring at unit substations

today, but monitoring is expanding over the next year.



High Tension Remote Monitoring•Con Edison has several hundred customers that are supplied via

primary feeders via a “high tension service.”•Over the next three years, many of these sites will be equipped

with remote monitoring capabilities and electronic meters to capture power and power quality measurements.



Customer Smart Meters•As part of a US$200 million project funded by federal stimulus

grants, Con Edison is establishing an infrastructure to collect measurements from a smart grid pilot project in Queens.

•Installation of 1500 smart meters that aim to permit customers to monitor and potentially improve their energy use.

•These meters will recordpower quality measurementsthat need to be integratedwith other sensor data beingcollected from area, network,and unit substations.



SCADA RTU Sensors•PQView Event Correlation•Automatic Momentary Interruption Analysis (MAIFI)•Voltage Schedule•Tap Setting Analysis



Distribution Capacitors•Also as part of the federal stimulus grant project, Con Edison will

be initiating the installation of SCADA ready switchable capacitors on the 4kV distribution system that will be integrated with PQ monitors and microprocessor relays at unit substations



Transmission Substations•Con Edison monitors transmission feeders using digital fault

recorder (DFR) systems in seventeen substations today.•Each DFR is configured to record waveform and rms samples for

up to 48 voltage and/or current analog signals.•At present, PQView is used to send e-mail alerts from the DFR

systems and provides correlation with SCADA on transmission feeders.


Overview of Data Integrationwith PQView at Con Edison Today

PQView

PQViewDatabase

Download Server for PQ Monitors and Phase Angle

Sensors

Download Server for Relays

SCADAServers

Web Service, IEEE PQDIF, and Proprietary Files

IEEE COMTRADE Files

Download Server for DFRs IEEE COMTRADE Files

SCADA Historian API

Proprietary Files from Portable PQ Monitors


PQView Projects at Con Edison

Automatic Bus Fault Analysis• Reactance estimates and fault duration calculated from waveforms captured

by power quality monitors and microprocessor relays at area substations. • PQView also integrates relay digital status values that indicate which

disturbance detection algorithms were triggered by an event in addition to which channel(s) triggered the operation of a circuit breaker.

• The e-mail notification and web reports produced by PQView assist operators in determining the source and location of the fault that caused the area substation bus to trip out; thus ensuring more rapid restoration of the area substation bus section when the root cause is a feeder fault and overcurrent trip of the bus.



Historical Fault Analysis•Integration with Poly Voltage Load Flow

– Distribution circuit model– Estimate of voltage at fault location based on substation

measurements •Integration with CAJAC

– database of laboratory describing the failure of each cable and joint

– automate root cause association•Follow-On Fault Analysis Module

– Cascading feeder failures



Steady State Regulation•Voltage Schedule•Transformer Tap Settings Balance in Phases and Transformers

13.3

13.4

13.5

13.6

13.7

13.8

80

100

120

140

160

3AM1 Tue Sep 2009

6AM 9AM 12PM 3PM 6PM 9PM 2 Wed

421LODV,421LODW

Electrotek Concepts® PiSlicer

KV

MW

Time

421LODV 421LODW



Arcing and Partial Discharge Detection•Con Edison plans to employ PQView with smart meter sensors

to mitigate the dangers associated with arcing events in underground vaults of the secondary network.

•Con Edison also plans to integrate devices in PQView that provide partial discharge measurements.– Partial discharge is localized dielectric breakdown of cable

that is detectable before a cable failure that results in a fault.

– Detection of which cable sections are demonstrating measurable partial discharge is a goal to proactively replace cables before they fail and increase the risk to a network’s reliability


Example Single-Phase Fault

IA

Voltage Drop

VA

I0 = 8kA

Total CurrentI0 = 4x2 kA = 8kA

I0 = 2kA

I0 = 2kA

I0 = 2kA

I0 = 2kA


Feeder Tripsdue to Fault

VisualFault

Locator

PQ Meter Captures

Waveforms

PQViewCalculates Reactance

-20

0

20

-5

0

5

0.00 0.05 0.10 0.15

Single-Phase Fault Evolves into Two-Phase

EPRI/Electrotek PQView®

Vo

ltag

e (

kV)

Cu

rre

nt

(kA

)

Time (s)

Va Vb Vc Ia Ib Ic

Match ReactanceTo Feeder Model

Dispatch Crews

1B 2AB2.195 2.216

10.0

12.5

15.0

17.5

1

2

3

2.5

5.0

7.5

10.0

0.05 0.10 0.15

Single-Phase Fault Evolves into Two-Phase

Vo

ltag

e (

kV)

Cu

rre

nt (

kA)

Re

act

an

ce (

oh

ms)

Time (s)

Va Vb Vc Ia Ib Ic XTF

Fault Locating Process


Relay RTF Website


Email Fault Notification


Feeder Fault with GE Relay Targets

PHASE IOC1 OP C On PHASE IOC1 OP C Off

-15000

-10000

-5000

0

5000

10000

15000

-20000

-10000

0

10000

20000

0.50 0.55 0.60 0.65 0.70

Murray Hill 12M77 - 9/10/2008 08:07:15.6374


Digital ChannelOsc Trig OnPHASE IOC1 OP CPHASE TOC1 PKP CGROUND TOC1 PKPTrip On

Vo

lta

ge

(V

)C

urr

en

t (A

)

Time (s)

Va Vb Vc Ia Ib Ic Ires


Fault Location Performance

57% Within 1 Section Length

18% 1 to 3 Manholes

7% 3 to 5 Manholes

6% 5 to 10 Manholes

12% >10 Manholes

Distance between Estimated Fault Location and Actual Fault LocationReactance-to-Fault Method, All Monitored Faults in 2009

Con Edison® PQView®


Transformer Magnetizing Inrush

•Con Edison uses the term “Cut-In Open-Auto” or CIOA to describe a feeder that trips immediately upon reenergization.

•A CIOA could be caused by the same or a new fault or by inrush current.

•If there is no fault, the feeder can be reenergized quickly, reducing stress and risk to a network.

•In 2007, Con Edison asked EPRI to enhance the functionality in PQView to detect inrush current and differentiate it from fault current.


Rea

l F

ault

Inru

sh E

ven

t

-10000

-5000

0

5000

10000

-2000

0

2000

4000

0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.18

E36THST - 12/16/2006 22:42:25.0650


Vo

lta

ge

(V

)C

urre

nt

(A

)

Time (s)

Va Vb Vc Ia Ib Ic In Ires

Fault Current versus Inrush Current


Incipient Fault Location Functionality

•Incipient Fault Location Functionality

-20000

-10000

0

10000

20000

-2500

-2000

-1500

-1000

-500

0

500

-1.0 -0.5 0.0 0.5 1.0 1.5 2.0

Vo

ltag

e (

V)

Cu

rre

nt (

A)

Time (c)

Va Vb Vc Ia

-20000

-10000

0

10000

20000

-3000

-2000

-1000

0

1000

2000

3000

-1 0 1 2 3 4 5 6 7 8

Vo

ltag

e (

V)

Cu

rre

nt (

A)

Time (c)

Va Vb Vc Ia Ib Ic

Reactance-to-Fault: 2.6 ohms


Digital Fault Recorders

•Minimum and maximum rms values of voltage and current, along with overcurrent duration in cycles, are available for all channels in an email notification

•The email notification is set to trigger if current on any channel exceeds 1500 A

•Correlation with breaker tags in OSIsoft® PI System® Historian is completed not via digital status changes but rather via changes in analog values


W72 Line Trip - Email Notification

Station / Timestamp

All ChannelsMin/Max RMS Values


W72 Line Trip - Email Notification

W72 Trip Out


W72 Line Trip – Max RMS Values


PI History at Con Edison

•SOCCS/SOCCS-X SCADA System – Designed by Boeing Company had a very limited data

archiving capabilities. The disk space on its system can only store data for eight days.

•PI was integrated with the SCADA system at Con Edison in 1997. •PI offered a solution for providing real-time RTU values and long-

term storage of both analog and digital status values

33© 2010 Electrotek Concepts, Inc. All rights reserved.33 Empowering Business in Real Time. © Copyright 2009, OSIsoft Inc. All rights Reserved.

60s 1h

5s 5s

Energy Management System

PI Data Integration

PI Tag

Bkr Trip


Linking PQView and PI Together

PI Server PQView PQ Data Manager

PiSlicerLibraryPI SDK

Con EdisonElectric OperationsPI System

PQViewDatabase

PiSlicer


Example Correlation

Single-Phase Distribution Fault Event

-20000

-10000

0

10000

20000

-2000

0

2000

0 2 4 6 8 10

BENSH1 - 3/12/2009 08:25:55.5630

Electrotek/EPRI Event ID = 510113 PQView®

OperationPoint Name BNBX21W.DXTime Stamp3/12/2009 08:25:56.0126Value B_HURST1 BKR 21W (10B66)Description CLOSE-TRIP

Vo

ltag

e (

V)

Cu

rre

nt

(A)

Time (c)

Va Vb Vc Ia Ib Ic


Example Correlation

Distribution Substation Capacitor Switching Event

-20000

-10000

0

10000

20000

-1000

0

1000

2000

0 2 4 6 8 10

GREENWD - 2/13/2009 06:09:39.0000


OperationPoint Name GRBXC2.DXTime Stamp2/13/2009 06:09:41.0040Value G_WOOD27 BKR C2 (CAP_2)Description TRIP-CLOSE

Vo

ltag

e (

V)

Cu

rre

nt

(A)

Time (c)

Va Vb Vc Ia Ib Ic


Example Correlation

Distribution Feeder Inrush

-20000

-10000

0

10000

20000

-2000

-1000

0

1000

2000

0 2 4 6 8 10

PLYMST - 12/12/2008 02:03:39.2500


OperationPoint Name PYBX31N.DXTime Stamp12/12/2008 02:03:39.0000Value PLYMOUTH BKR 31N (1B61)Description TRIP-CLOSE

Vo

ltag

e (

V)

Cu

rre

nt

(A)

Time (c)

Va Vb Vc Ia Ib Ic


Example Correlation

Multiple Breaker Trips due to Substation Fault

-15000

-10000

-5000

0

5000

10000

15000

-10000

-5000

0

5000

10000

0 2 4 6 8 10

PKCHEST1 - 3/2/2009 02:18:28.1250


OperationsPoint Name PKBX32E.DXTime Stamp3/2/2009 02:18:31.0241Value PARK_CH1 BKR 32E 7X78Description CLOSE-TRIP

Point Name PKBX33E.DXTime Stamp3/2/2009 02:18:31.0241Value PARK_CH1 BKR 33E 7X81Description CLOSE-TRIP

Point Name PKBX3BT.DXTime Stamp3/2/2009 02:18:31.0241Value PARK_CH1 BKR 3BTDescription CLOSE-TRIP

Point Name PKBX3TR.DXTime Stamp3/2/2009 02:18:31.0242Value PARK_CH1 BKR 3TR 38X03Description CLOSE-TRIP

Point Name PKBX7TR.DXTime Stamp3/2/2009 02:18:31.0242Value PARK_CH1 BKR 7TR 7X24Description CLOSE-TRIP

Vo

ltag

e (

V)

Cu

rre

nt

(A)

Time (c)

Va Vb Vc Ia Ib Ic


Follow-On Fault Analysis Module


I²T Calculation and Notification

-4

-3

-2

-1

0

1

2

3

4

0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.18

Cu

rre

nt

(kA

)

Time (s)

Ia Ib Ic

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.18

Cu

rre

nt

(kA

²·t)

Time (s)

Ia Ib Ic


Automatic DistributionCapacitor Analysis

•Capacitor Switching Transient Identification•Capacitor Bank Direction Indication•Capacitor Bank Health Analysis•Abnormal Capacitor Bank Switching Operation


Electrotek/Dranetz Capacitor SwitchingAnswer Module®

•Development begun in 1998 as an optional component of the Electrotek/Dranetz-BMI Signature System.

•Provides answers to these questions:– Do the voltage and current waveforms captured by the

power systems monitor appear to be a capacitor switching transient? • Does the capacitor event appear to be normal? • Does the capacitor event appear to be magnified? • Was the reactive power change on all three phases

balanced? • What was the reactive power change on each phase?


Capacitor Switching Answer ModulePorted to PQView Module


Example of Answer Module Output

-20000

-10000

0

10000

20000

-2000

-1000

0

1000

2000

0.00 0.05 0.10 0.15

GREENWD - 2/26/2009 10:39:51.5630

Electrotek/EPRI PQView®

Event ID 33GPS Synch NoEvent Base Voltage 15242Event Fund Frequency 60Reference Cycle Number 31650System Event ID Valid YesM.E. RMS Variation NoM.E. Interruption NoMonitor Availability NoLoad Interruption NoB1 NoB2 NoB3 NoCapacitor Directivity Direction DownlineCapacitor Directivity Confidence HighCapacitor General GeneralCapacitor Magnification No MagnificationCapacitor Normal NormalCapacitor Q Balance BalancedCapacitor Q Delta A -2224263Capacitor Q Delta B -2205492Capacitor Q Delta C -2239395Capacitor Q Delta Total -6669149

Vo

ltag

e (

V)

Cu

rre

nt (

A)

Time (s)

Va Vb Vc Ia Ib Ic Ires


Example of Answer Module Output

-2.216-2.160

-2.235

2.5

3.0

3.5

4.0

4.5

5.0

5.5

0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.18

GREENWD - 2/26/2009 10:39:51.5630Reactive Power

?Qa=-2.216 Mvar ?Qb=-2.160 Mvar ?Qc=-2.235 Mvar

Electrotek/EPRI PQView®

Re

act

ive

Po

we

r (M

var)

Time (s)

Qa Qb Qc


Capacitor Identification: Next Steps

•Link SCADA Correlation Module and Automatic Capacitor Analysis Together

•Abnormal Capacitor Bank Switching Operation– Restrike, and Magnification

•Synchronous Closing Performance•Harmonic Resonance Identification and Trending

Documents

Peter Hofmann Chief Engineer-Distribution Engineering Consolidated Edison, New York PQView User Group Meeting New York, NY August 31 – September 02, 2010