micom ieds for process bus_experts 2012

GRID

MiCOM IEDs ForProcess Bus Applications

April 2009

Experts Training 2012

Stafford, United Kingdom

Scope

Digital Substations & Process Bus Overview Page 3

MiCOM IEDs for Process Bus 1

Px4x -9-2LE Interface Features Page 31

Process Bus Architectures Page 47

Testing, Conclusion Page 60

Presentation title - 01/01/2010 - P 3

Reference Digital SS Architecture across Grid

Proxy

Multiple Ethernet

IEC61850.8-1

Station Bus

C37.118 Phasor Data

Grid Control

Rooms

AMU

Primary Eqpt with

embedded sensors

for Condition Monitoring

Prot. Px40

DRUs

Switches

WAN

CMU

SCS HMI

Multiple Ethernet

IEC61850.9-2 &

IEC61850.8-1

Process Bus

Digital SS ComponentsIntegrated Substation Automation System with

1. Substation Control System (SCS)

2. Condition Monitoring System (CMS)

3. Smart Grid Applications (SG APPS – Cyber,

Intrusion,

Wide Area Management)

4. Substation Phasor Data Concentrator

Several IEDs

1. Protection / Measurement with 9-2 interface

2. Bay Controller Unit (BCU)

3. Condition Monitoring Unit (CMU)

4. Switches & Telecom

5. Proxy Server

6. Merging Units (AMU, DMU, NMU – for

NCIT)

7. Wide Area Control Unit (WACU)

8. Power Quality /Disturbance Record Unit

(DRU)

9. Energy Meters

DMU

SG APPSCMS PDC

WACU

BCU

Other

substations

sPDC

SG APPS

IEC 61850 Process Bus

Process Bus Elements� Ethernet Network, 100 Mb/s

� IEC 61850-9-2 LE for Sampled Values “SV”

� Current measurement (CT)

� Voltage measurement (VT)

� IEC 61850-8-1 GOOSE Service

� Status position of Circuit Breaker / Switches (CB)

� Trip signals from protections to CBs (Trip)

� Commands from Control Systems (Open/Close)

� Others (monitoring status reports, health, settings…)

� Time synchronisation

� Microsec accuracy required


61850-9-261850-9-2

61850-8-1

61850-8-1

Bay Level

Protection Control

Station Level

Function A Function B

HV Equipment

Bay Level

Protection Control

HV Equipment

33

11

33

1166 66

99

44 55 44 55

88

77 Technical ServicesLogical View Of SA

IEC 61850 -9-2 Overview

� Sampled Value Transmission

� Unidirectional link (MU to IED)

� Physical layer : Optic fibre (copper optional)

� Data Link layer : Ethernet 100 Mbit/s

� Application Layer : IEC 61850-9-2 “Light Edition” guideline to aid implementation and interoperability

� Sampling rate : 80 or 256 samples per cycle

� Neutral current and/or voltage may be measured, or derived

� Sampled values are multicast on the LAN

� Defines Logical Device “MU”

� Synchronising of sampling


4V; 4I

4V; 4I

� IEC 61850-9-2LE Sampled Values

� Each SV message carries 4 voltages + 4 currents

� Primary values, quality info

� Current : 1mA to 2.14 MA, Voltage : 10mV to 21.4 MV

MU-L1

MU-L2

Protection

Bay 1Protection

Bay 2

(I1a, I1b, I1c, I1n, V1a, V1b, V1c, V1n)

(I2a, I2b, I2c, I2n, V2a, V2b, V2c, V2n)

HQ_IEC 61850 Process Bus_06/2011


� SV frames are multicast

� MAC Address range: 01-0C-CD-04-00-00 to 01-0C-CD-04-1F-FF

input on Merging Units

� Note the frame overhead : 24 bytes of ‘raw data’ (per 3-phase

voltage and current) in about 125 byte Ethernet frame

Ia x 1000

32 bit Int

Ia Quality

32 bits

Ib x 1000

32 bit Int

Ib Quality

32 bits

Ic x 1000

32 bit Int

Ic Quality

32 bits

In x 1000

32 bit Int

In Quality

32 bits

Va x 1000

32 bit Int

Va Quality

32 bits

Vb x 1000

32 bit Int

Vb Quality

32 bits

Vc x 1000

32 bit Int

Vc Quality

32 bits

Vn x 1000

32 bit Int

Vn Quality

32 bits

-9-2LE Sampled Value Frame


Merging Unit – Typical Naming

� AMU : Analogue Merging Unit

� Interface with conventional instrument transformers

� DMU : Digital Merging Unit

� Interface with CB / isolators / earth switches

� CMU : Condition Monitoring Merging Unit

� DMU with condition monitoring features

� NMU : Numerical Merging Unit

� Interface with digital instrument transformers



� Main 1, Main 2, BCU

� Individual CT cores per IED

� Independent tripping paths for Main 1 and Main 2 typically

CB

Status &

Trips

Conventional Bay Protection & Control – Example



DM

U#

1

-8-1 PRP

AM

U #

1

-9-2LE

DM

U#

2

-8-1 PRP

AM

U #

2

-9-2LE

AM

U #

3

-9-2LE Process Bus

(conceptual)


� AMU, DMU

� Ethernet links and switches

� Time synch eqpt

Digital Bay Protection & Control – Example



� Sampling across multiple analogue MUs may need to be

synchronised � Protection functions/algorithms require all input quantities to be

supplied in ‘real time’

� Relay inputs may be from multiple MUs

o Substation layout

o Customer specifications

� Similar to synchrophasor measurements

Eg: Distance Protection (Voltage & Current)

� Both voltage & current could be supplied by one MU –

synchronisation integral to the MU

� Voltage from MU1 and current from MU2 - synchronisation

requires common time reference input to MUs

AMU - Sampling Synchronisation


V˂0

I˂-36

V˂-18

I˂-81

1 ms delay

2.5 ms delay


→ SV frames from different MU may have uneven delays

→ Relay measurements will be incorrect unless the SV frames are time-aligned


� Techniques

� 1 PPS input on Merging Units

� Merging Units with capability for IEEE 1588 synchronisation

� Sampled Value frames carry synchronisation info

� Time tags (count) relative to the start of the ‘sec’

� Identifier for sync source – Global, Local or No Sync

Indicates if the SV

frame is synchronised

Sample Count0 – 3999 at 50 Hz

0 – 4799 at 60 Hz

Counter resets every sec when a

time sync signal is received



Relay - Sampled Values Alignment


� Time alignment of SV frames is necessary, and ensures correct operation of protection functions dependent on multiple MU’s� The number of MU’s may change depending on site

requirements and customer preferences

� Delays arise from

� Merging Units, due to their processing

� Network, depending on its configuration and switches

� Delays have a direct impact on the operating time of the scheme

� Time tags (count) relative to the start of the ‘sec’

� Identifier for sync source – Global, Local or No Sync


� Sampling Synchronisation Accuracy� Time source accuracy +/- 1µs

� Sampling across multiple MUs synchronised to within +/- 4µs

� MU should be capable of compensating network delays > 2µs

MiCOM P594



� 1 Pulse Per Sec (1PPS) Signal� Transmitted by fibre as medium

� Rise and fall time < 20ns

� Clock source : Typically based on GPS

� Global 1PPS: 1PPS source is synced to GPS, pulse width between 5µs and 500 ms

� Local 1PPS : 1PPS source running on internal clock, pulse width between 0.9µs and 1.1µs

1PPS

P594 Merging Unit



� Sync Flags in SV Frame

� Carried by the field smpSync

� Global 1PPS: Ideal, no impact on protection functions

� Local 1PPS : Some protections may have to be blocked

eg: Feeder differential

� No Sync : No 1PPS at AMU, running on AMU internal clock.

o Protections dependent on multiple MUs for data may be blocked, eg: distance protection with two CT inputs)

o MU said to be in ‘Holdover Mode’

-9-2LE SAV

Merging Unit



� IEEE 1588 Basics

� It is a high precision time synchronization (<1us) for

synchronising real-time clocks on an Ethernet LAN

� Also called PTP – Precision Time Protocol

� Current standard : IEEE 1588 version 2

� No need for separate cabling (IRIG-B, 1PPS)

� Fault tolerance using Redundant Clocks


Scope


MiCOM IEDs for Process Bus Page 21




MiCOM Px4xProcess Bus Applications

� Range of IEDs with IEC 61850-9-2LE interface

� Covers major transmission applications –distance, current differential, transformer, backup / circuit breaker IED and busbarprotection

� Full IEC 61850 Process Bus integration in combination with existing IEC 61850-8-1 interface

� Tried and tested protection functionality

Now ready !

IEC 61850-9-2LE

Sampled Values

80 samples / cycle


MiCOM Alstom

P446Distance protection, with integral teleprotection

and one / two breaker reclosing

MiCOM Alstom

P546Line differential for 2 or 3 terminal lines, with

distance and one / two breaker reclosing

MiCOM Alstom

P645Transformer differential for up to 5 ends, with

advanced loss-of-life thermal monitoring

MiCOM Alstom

P746Numerical busbar protection

MiCOM Alstom

P841Transmission line terminal IED, for backup,

reclose and breaker fail management

Relay Types Available

MiCOM Px4x Process Bus Applications

Process Bus Interface

Interface for -9-2LE

Sampled Values

Interface for -8-1 GOOSE

and Station Bus



� Point to point connections

� Feasible when all the SV required by a relay are available from a single MU

� Simple network, minimum delay, minimal engineering effort

Interfacing SV to Px4x

-9-2LE


Interfacing SV to Px4x – Transformer Protection

P645

HV+LV+TV

HV Current - 1

HV Current 2

TV Current - 1

TV Current - 2

LV Current

Point to point

connection

not possible


� Networked connections

� Required if the SV required by a relay are from multiple MU, eg: transformer IED, busbar IED

� Ethernet switch(es) involved, possibility of additional delays and sample jitter; substation-hardened switches required, similar to Station Bus applications.


-9-2LE


� Networked connections - redundancy

� If required, network redundancy for SV may be achieved by external devices such as a RedBox.

� The GOOSE / Station Bus interface does provide network redundancy (proprietary – SHP, DHP; open : RSTP, PRP)


LAN A

LAN B


-9-2LE Interface Features: LN Assignment

� Upto 8 Logical Nodes available for flexible assignment of Sampled Values

� Number of MU’s may varydepending on substation layout and customer preferences

� Analogue input groups as in conventional relay

P446 Configuration


Interfacing SV to IED – Eg: Transformer Protection

P645

HV+LV+TV

Logical Node

HV Current 1

Logical Node

HV Current 2

Logical Node

LV Current

Logical Node

TV Current 2

Logical Node

TV Current 1

Scope







Processing SV – Eg. P446

CT / VT

Input Module

IA, IB, IC

VA, VB, VC

Analog

Inputs48 samples /

cycle

IA (k), IB (k),

IC(k)

VA(k), VB(K),

VC(k)

80 samples /

cycle

Px4x with -9-2LE board

IEC 61850

Merging

Unit

-9-2LE

Interface

Board 48 samples /

cycle

IA, IB, IC

VA, VB, VC

Analog

Inputs

IA (n), IB (n),

IC(n)

VA(n), VB(n),

VC(n)

IA (n), IB (n),

IC(n)

VA(n), VB(n),

VC(n)

Relay CPU/

Co-processor

Relay CPU/

Co-processor

Px4x with analog inputs


The Px4x -9-2LE interface conditions the SV to enable reuse of

tried and tested protection algorithms


-9-2LE Interface Features: SV Synchronisation

� Setting for global/local synch for SV received� Adapt relay to functional requirements of the protection scheme� Common setting for all functions enables in the relay

Eg: P446 receiving SV from AMU1 (voltage) and AMU2 (current)

Case 1: Both AMU1 and AMU2 have common source of time sync, Local Sync setting is sufficient

Case 2: Time sync sources for AMU1 and AMU2 are different, Global Sync setting is required

AMU : Analogue Merging Unit

ESW : Ethernet switch

AMU 1

AMU 2

ESW



� Time alignment of SV frames is necessary, and ensures correct operation of protection functions dependent on multiple MU’s� The number of MU’s may change depending on site

requirements and customer preferences

� Delays arise from

� Merging Units, due to processing

� Network, depending on its configuration and switches

� SV alignment by MU Delay setting

AMU 1

AMU 2

AMU 3

ESW

AMU : Analogue Merging Unit

ESW : Ethernet switch

-9-2LE Interface Features: SV Alignment



Case 1: Relay with

1 MU

Case 2: Relay with

2 MU

Case 3: Relay with

2 MU

MU Delay: Relay setting,

indicates worst case relative

delay expected in receiving

SV from all MU’s linked to

the relay

In this case, no delay

between SV frames from

MU#1 and MU#2

In this case, there is a 1ms

delay between SV frames

from MU#1 and MU#2

-9-2LE Interface Features: SV Alignment


-9-2LE Interface Features

� Security against loss of SV

� Setting for SV Loss Rate� Loss rate evaluated per LN� Related protection functions blocked if Loss Rate exceeds the set value

� SV communication network statistics to facilitate commissioning, network monitoring and troubleshooting

� LNx Loss Rate Sec (x: 1….8)� LNx Frame Loss Cuml (x: 1….8)� LNx Error Sec (x: 1…..8)


-9-2LE Interface Features : Test Mode

� IEC 61850-9-2LE test mode aware

� Facilitates testing and commissioning� Common setting for all Logical Nodes

Test Blocked: All SV with an IEC 61850 Test flag are treated as invalid. The IED blocks relevant protection

functions and issues a ‘9-2 Sample Alarm’.

Test Ignored: All SV received with an IEC 61850 Test flag are treated as good, protection functions remain active.

Test Only: All SV with an IEC 61850 Test flag are treated as good. Any channel data received without the Test flag

are treated as invalid. The IED blocks relevant protection

functions and issues a ‘9-2 Sample Alarm’.


Enhanced GOOSE Capability

� The -9-2LE relay models have more configurable GOOSE inputs / outputs comparable to standard relays

� Facilitates full Process Bus implementation

Standard Px4x Px4x with -9-2LE


MiCOM P446 v72

� Distance protection with -9-2LE interface

� Configurable for single or double current (three-phase) inputs, thus covering P443 and P445 applications

� Enhanced -8-1 GOOSE count compared to P446 with analogue inputs, facilitates full Process Bus implementation

� Channel-aided schemes with standard distance relays at remote end – no need to retrofit -9-2LE at both line ends


MiCOM P841 v72

� Line terminal IED with -9-2LE interface

� Autoreclosing and circuit breaker failure for one or two breakers

� Configurable for single or double (three-phase) current inputs, covering P841A and P841B applications

� For backup overcurrent / earth fault applications where -9-2LE interface is called for


A

B

C

LD1

LD2

BUS A

BUS B


MiCOM P546 v72

� Current differential protection with -9-2LE interface

� Functionally equivalent to P546 v57 (with CT/VT inputs)

� Configurable for single or double (three-phase) current inputs, covering majority of P543, P544 and P545 applications

� Application requires GPS synchronisation (1PPS) on all relays in the current differential scheme

� Enhanced -8-1 GOOSE count compared to P546 with analogeinputs, facilitates full Process Bus implementation


MiCOM P546 v72

� Current differential schemes in ‘mixed mode’ combining -9-2LE relays and those with analogue inputs


MiCOM P645 v11

� Transformer protection with -9-2LE interface

� Functionally equivalent to P645 v03 (with analogue inputs)

� Configurable for uptofive sets of (three-phase) current inputs, covering P642 (two-winding) and P643 (three-winding) applications

� Enhanced -8-1 GOOSE countcompared to P645 with analogue inputs

-9-2LE

-8-1


MiCOM P746 v11

� Centralised busbar protection with -9-2LE interface� Functionally equivalent to P746 v03 Note: Three-box mode is not available in the -9-2LE relay



Common (platform) features

� Interoperable : Implementation of SV interface as per IEC 61850-9-2LE Guideline for 80 samples/cycle

� All the -9-2LE relays are built on the latest M-hardware (XCPU3)

� Ease of Configuration: -9-2LE parameters are part of the relay setting (.set) file

� Cybersecurity: Features as per current MiCOM implementation

� Redundancy: Option for -8-1 GOOSE , Parallel Redundancy Protocol implementation


Cortec/Ordering

� All -9-2LE relays are on M hardware only

� Option for -9-2LE in CORTEC for P446, P546, P645, P746, P841

� IEC 61850-8-1 port / protocol options are the same for relays analogue inputs or -9-2LE inputs

� Important: P594 is mandatory for ALL P546 relays in a current diff scheme

P594 version D

Scope









� Individual CT cores per IED

� Independent tripping paths for Main 1 and Main 2 typically

CB

Status &

Trips

Conventional Bay Protection & Control – Example


DM

U#

1

-8-1 PRP

AM

U #

1

-9-2LE

DM

U#

2

-8-1 PRP

AM

U #

2

-9-2LE

AM

U #

3

-9-2LE Process Bus

(conceptual)

Digital Bay - Typical� Main 1, Main 2, BCU

� AMU, DMU

� Ethernet links and switches

� Time synch eqpt


CB

H xxx

H xxx

P594

E

D

A

B

C

A

B

C

D

E


Digital Bay – DetailedArchitecture

� Merging Units - AMU, DMU

� Time synch by 1PPS

� Redundancy for binary I/O

CB

AM

U #

1

-9-2LE

P594A

MU

#2

-9-2LE D

AM

U #

3

-9-2LE

A

B

C

BC

U

-9-2LE

I/O Card

Ma

in 2

-9-2LE

I/O Card

Ma

in 1

-9-2LE

I/O Card

A

B

C

D

MiCOM IEDs for Process Bus ApplicationsPossible migration strategy

Physical

Wiring

Retain all existing DC wiring

Change only CT / VT interface


Process Bus ArchitecturesAdditional Info

SGCC China


National Grid UK - Under Discussion

Concerns

- Reliability of Sampling Sync

- Inter-bay Process Bus


Extracts from recent ‘Big Red’ paper*

� Five typical Process Bus architectures compared in relation to multiple criteria

� Criteria chosen� Reliability and availability � Cost : Initial investment + maintenance cost� Performance: Average network load, worst case transmission delay

* A Quantitative Evaluation of IEC61850 Process Bus Architectures

Jean-Charles Tournier & Thomas Werner,

ABB Corporate Research






Main 1, Main 2, BCU

AMU x 1, DMU x 1

Switch x 1

Fibre links

Copper links

Main 1, Main 2, BCU

AMU x 2, DMU x 2

Switch x 2

PRP on all IEDs






Fibre links

Copper links

Main 1 with BCU, Main 2 with BCU

AMU x 2, DMU x 2

Ring with RSTP on all IEDs

Alt. Ring with HSR on all IEDs

Main 1, Main 2, BCU

AMU x 2, DMU x 2

Ring with RSTP on all IEDs

Alt. Ring with HSR on all IEDs






Main 1 with BCU per bay

Main 2 with BCU in common IED

AMU x 1, DMU x 2

RB: HSR Red Box

QB : HSR Quad Box






Notes: � Only component costs considered; engineering, testing and commissioning

may have significant impact. � Project specifications (eg: number of MUs per bay, protection operating

time) may become the deciding factor for architecture � Primary plant technology may lead to alternative conclusions

Scope






IED (SV

Interface)

V I

Ethernet

Switch

PC

Ethernet

GOOSE

and SV

GOOSE

and SV

Trip

IEC 61850

Test Kit

IED Conventional

Trip

� Testing of -9-2LE relays require test kits with capability for

� Send / receive GOOSE

� Generate SV– one or more logical nodes

� Display Sampled values

� Time synchronisation

� Testing may also call for Ethernet switches, Time sync source

Set-up for comparing performance of IEDs

- Standard vs -9-2LE


IED Testing


Customer Benefits

� Eliminate or reduce significantly the use of copper in secondary circuits

� Fibre optic replaces copper� Enhances operator safety� Eliminates EMI on secondary cabling

� Delinks data acquisition (currents, voltages) from signal processing / algorithms � Potential for reduced shut-downs for refurbishment� Relays (algorithms) may be upgraded independent of

acquisition

� Easier integration of sensors into smart grid solutions

GRID

http://www.alstom.com/grid/sas/

micom ieds for process bus_experts 2012

Documents