Dewey Day, Principal IT Architect – PG&E Doug Arnold, Principal Technologist – Symmetricom & IEEE 1588 Study Group Co-Chair Precision Time Protocol (PTP) and Power Profi le
Dewey Day, Principal IT Architect – PG&E
Doug Arnold, Principal Technologist – Symmetricom & IEEE 1588 Study Group Co-Chair
Precision Time Protocol (PTP) and Power Profile
Project Objectives
ACCURATE
Great than 1 µSec Accuracy
Lengthy Holdover
Quantifiable Performance
DISTRIBUTABLE
Ethernet Based
No Special Cabling
Simple Deployment for any
Environment
SECURE
Defined Fail Over Parameters
Alarming on
Errors
Substation Hardened
Synchrophasor Clocking Source & Evolution for Other Substation Devices
PARTNER
Established Industry Leader
Proven
Development Capabilities
Power Specific
STANDARDS BASED
3 Confidential © Copyright 2012
Time Transfer Technologies
IRIG-B (S)NTP PTP
Accuracy (typical) 1-10µs 1ms – 10 ms 100ns-1µs
Transport media Dedicated cables Ethernet cables Ethernet cables
Protocol style Master-slave Client-server Master-slave
Built in latency correction No Yes Yes
Set-up Configured Configured Self-organizing, or configured
Update intervals 1 second Minutes 1 second
Specialized hardware Required No Required
Redundant masters for N-1 contingency
No Yes Yes
7 Confidential © Copyright 2013
PTP Profiles
• PTP options – Many optional features – Works over many network types – Used in several different industries – Interoperability between PTP enabled devices is not guaranteed!
• Profiles – More restrictive set of rules for specific application – Specifies:
• Required options • Allowed options • Forbidden options • Network topology limitations
8 Confidential © Copyright 2012
IEEE 1588 Power Profile Standard 2011
• IEEE C37.238-2011 Standard - Profile for IEEE 1588 Precision Time
Protocol in power system applications
• Profile Characteristics: - LAN (Layer 2 Ethernet Mapping) - Multicast addressing only - Peer-to-peer delay measurement - Switches must be Transparent Clocks - Time transfer accuracy and holdover
time defined
• IEC 61850 will add C37.238-2011 as a requirement in the future.
• http://standards.ieee.org/findstds/standard/C37.238-2011.html
9 Confidential © Copyright 2012
PTP Power Profile
1 microsecond time accuracy, < 16 hops
Grandmaster Clock
Transparent Clock
Transparent Clock
PTP Power Profile delivers microsecond timing in the Smart Substation
10 Confidential © Copyright 2013
Smart Substation WAN/LAN Timing Solution
IRIG-B Bus
RELAY ROOM
Event Recorder
IRIG-B C37.118.1-2011
Protection Schemes
Remote Terminal Unit (RTU)
PPS, PPM
Subs
tatio
n Cl
ock
GPS/GNSS
ADM
DS1 G.703 9/13
COMMUNICATION ROOM
IEEE 1588 GMC TP5000, SSU 2K, Time Hub IEEE 1588 PTP
Telecom Profile
Utility WAN SONET/SDH
Protection Relay
Alarm Annunciator
Substation Gateway
QOS Meter
Substation Switch (Transparent Clock)
61850 LAN
IEEE 1588 PTP Power Profile
NTP
PMU
PG&E Deployment
Existing IRIG-B Clock (JIC) Hub to Sub - Standards Based
1588 Telecom Profile Distribution
Remote Synchronization Source
Sub to Device - Standards Based 1588 Power Profile Distribution
Fiber Based Ethernet Cabling Whenever Possible
Local Source Substation Hardened – Rb Holdover
Full Redundancy This is only half of the picture!
Transparent Clock Distribution to All Devices