Copyright © SEL 2009Copyright © SEL 2009

Trends in Station Bus and Process Bus

Communications Via the Several

IEC 61850 Protocols

Schweitzer Engineering Laboratories, Inc.

Reduce Cost / Complexity of Field Wiring

1. Traditional Topology

Physical

Equipment

Terminal

BlockRelay

Marshalling

Cabinet

Terminal

Block /

Test Plug

44 Wires 44 Wires 44 Wires 44 Wires

Yard House

2. Relays in Yard

Physical

Equipment

Terminal

Block /

Test Plug

Relay44 Wires 44 Wires

Yard

3. I/O

Modules in

Yard

Physical

Equipment

Terminal

BlockRelay

Terminal

Block /

Test Plug

Marshalling

Cabinet

I/O

Transceiver

44 Wires 24 Wires

20 Wires

24 Wires24 Wires

1 Cable

YardHouse

4. Merging Unit Topology

Physical

Equipment

Terminal

Block /

Test Plug

RelayMerging

Unit

Switch or

Processor

44 Wires 44 Wires 1 Cable 1 Cable

Yard House

Va, b, c,

neutral, busbar

la, b, c, neutral

(prot)

la, b, c

(meas)

Merging

Unit

Digital

Communication

Po

we

r S

up

ply

Clo

ck In

pu

tD

iscre

te S

tatu

s

an

d A

larm

Merging Unit Concept Aggregates Data

Onto Digital Link

Discrete I/O, Programmable

Automation Controllers, and RTDs

Multiple Merging Unit Payloads

• Discrete only: DMU

• Measured analog plus discrete: MMU

• Temperatures: TMU

• Synchrophasors: PMU

• Smart breaker: BMU

• Sampled (raw) analog plus discrete: MU

• SMART Protocol™ – metering, targets,

equipment data, temperatures, and

synchrophasors

• IEC 61850 GOOSE, Sampled Values (SV)

• IEEE C37.118 synchrophasors

• IEEE 1588–2008: precision time

synchronization (in progress via PSRC)

Process Bus Protocols Move Analog

Values, Discrete Status, and Alarms

SEL Devices Publish and Subscribe

MIRRORED

BITS® DMU

Fast Message

MMU

Fast Message

PMU

IEC 61850

GSE DMU

IEC 61850

GSE MMU

IEC 62271

BMU

IEEE C37.118

PMU

MIRRORED

BITS DMU

Fast Message

PMU

IEC 61850

GSE DMU

IEC 61850

GSE MMU

IEC 62271

BMU

IEC 61850-9-2

MU

IEC 61850-9-2

MU

Publications

Fast Message

TMU

IEEE C37.118

PMU

Subscriptions

SEL Provides Integration Choices

Nonrouted Architecture Routed Architecture

Focus on IEC 61850 Protocols

• Reporting, polling, and control via

client server (MMS)

• Control and unsolicited updates via peer to

peer (GOOSE or SV)

• Primary equipment data acquisition peer to

peer (GOOSE or SV)

Ethernet

Ethernet

Switched Ethernet Station and

Process Bus From Beginning

Process Bus Shares Data Among IEDs

and Smart Sensors

Bay

Controller

Relay

A

Relay

B

Modern

Switchgear

Modern

CT / VTs

Process Bus

SEL ApproachUse Global, Standardized Methods

• Offer choice of installation method / location

• Provide highest protection reliability

• Continue lowest system / installation cost

• Use existing protection

• Design for interoperability

• Provide system-wide protection and

synchrophasors

Relay-Based Process Bus System

Process

Level

Bay

Level

Instrument Transfer

Merging Unit

50, 51, 21

Breaker Controller

Breaker

Station

Level

Time Source

Ethernet Switch

Station

Controller

HMI

Ethernet Switch

87BFR

Advantages of SEL Approach

• Primary protection continues if

communications fail

• Minimum number of devices

• Relay receives and transmits IEC 61850-9-2

• Fixed-rate sampling

• Absolute time reference per IEEE 1588

• Share analog data among devices

Flex Connect Choose From Several Standard Connections

• Reduce wiring

• Reuse data

• Recycle information

Choose Any Installation Method:

Interoperable – Multivendor

Relays in

control building

Relays in field

termination kiosks

Flex Connect: Flexible Data

Acquisition and Control – Multivendor

• SELECT Direct: standard, hard-wired copper

conductors

• SELECT Fiber: digital communications over

standard, fiber-optic cable

• Hybrid

♦ Analog via SELECT Direct

♦ Discrete via SELECT Fiber

SELECT Direct Connectorized® or Conventional Copper

Conductor Terminations

Choose from copper off the spool or

premade harnesses

SELECT Fiber Digital Communication Over Standard

Fiber-Optic Cable

Choose fiber off the spool or premade cables

SEL Confidential

HybridDigital Communication Via Standard Fiber

Plus Conventional Copper Conductors

• Copper off the spool

• Premade harnesses

• Fiber off the spool

• Premade cables

Choose from:

Compare Four-Feeder Substation SAS

Communications and

control building (CCB)

Communications and

control kiosk (CCK)

Field termination cabinet

(FTC) and kiosk (FTK)

Copper

conductors

(CCs)

Fiber

connectors

(F)

Process Bus

SELECT Direct

Hard-Wire

• 72 CC analog

• 60 CC discrete

Station Bus

SELECT Fiber

Fiber Process Bus FTK

• SEL MU

• Publish / subscribe

SV and GOOSE

Hybrid Process Bus FTK

• SEL DMU

• Publish / subscribe

GOOSE

• Analogs via CCs

Process BusHybrid

• SELECT Fiber

Star, 6 F digital

• SELECT Direct,

72 CC analog

Station Bus SELECT Fiber

Active Redundant Network: Dual Ethernet

“Failover” – IED Controls Data Flow

Survive loss of any

switch, cable, relayNetwork

Process BusHybrid

• SELECT Fiber Dual

Star, 12 F digital

• SELECT Direct,

72 CC analog

Station Bus SELECT Fiber

Passive Redundant Network: Internal Ethernet

Switches – Switch Controls Data Flow

Survive loss of any

switch, cable, relayNetwork

Managed

Ether

Switch

Managed

Ether

Switch

Process BusHybrid

• SELECT Fiber

Ring, 7 F digital

• SELECT Direct,

72 CC analog

Station Bus SELECT Fiber

Merging Units Support SV and GOOSE

But Disable Local Protection

Process Bus

SELECT Fiber

Star, 6 F

Station Bus

SELECT Fiber

Process Bus

SELECT Fiber

Dual Star, 12 F

Station Bus

SELECT Fiber

Fiber Optics Replace Copper

Process Bus

• SELECT Fiber

Star, 7 F

• Unused

Station Bus

SELECT Fiber

Process Bus

SELECT Fiber

Star, 7 F

Station Bus

SELECT Fiber

Station

Controller

Rev.

Meter

Ethernet

Switch

Ethernet

Switch

Time

Source

Instrument

Transfer

Merging Unit, Disable Local Protection,

But Maintain Breaker Control

Merging

Unit

Breaker

Controller

Process

Level

Bay/Unit

Level

Station

Level

Breaker

Merging

Unit

Breaker

Controller

Instrument

Transfer

Breaker

87

50, 51,

21

50, 51,

21

50, 51,

21

50, 51,

21

Station

Controller

Revenue

Meter

Ethernet

Switch

Ethernet

Switch

Time

Source

Instrument

Transfer

Merging Unit Plus Local Protection

Supporting System Protection Over LAN

Merging

Unit

87

Breaker

Controller

Process

Level

Bay/Unit

Level

Station

Level

Breaker

50, 51, 21

Merging

Unit

Breaker

Controller

50, 51, 21

Instrument

Transfer

Breaker

Merging Unit With I/O

Time

Source

Merging

Unit

Instrument

Transf.Ethernet

Switch

Relay Ethernet

Switch

Breaker

Controller

Switched System MTBF = 300 / 4 = 75 Years

Process Level Bay/Unit Level Station Level

Station

Controller

Breaker

Merging Unit With Intelligence

Performing Local Protection

Time

Source

Merging

Unit

Instrument

Transf.

Relay

Ethernet

Switch

Breaker

Controller

System MTBF = 300 Years

Process Level Bay/Unit Level Station Level

Station

Controller

BreakerRevenue

Meter

Merging Unit Plus Local Protection

Supporting System Protection Over LAN

Time

Source

Merging

Unit

Instrument

Transf.

Ethernet

Switch

87

Ethernet

Switch

Breaker

Controller

Localized Protection MTBF = 300 Years

Merging Unit Prot. MTBF = 300/4 = 75 Years

Process Level Bay/Unit Level Station Level

Station

Controller

Breaker

50, 51, 21

Revenue

Meter

2nd Merging

Unit for 50,

51, 21, 87

Replace Copper

With Fiber,

Monitor Health of

Signal, Reduce

Footprint / Cost