This document discusses various communication protocols used in power systems and smart grids. It provides overviews of DNP3, C37.118, OPC, IEC 61850 and IRIG-B protocols. DNP3 allows communication between intelligent electronic devices and SCADA/EMS systems to monitor and control electrical networks. C37.118 defines synchronized phasor measurements for wide area monitoring. OPC provides a common interface for process control devices. IEC 61850 specifies communication for substation automation. IRIG-B transmits a timecode signal for synchronization. The protocols support bidirectional communication of measurements and enable interoperability between different devices.

1. New communication
protocols
Applications & Implementation

2. Contents
 Why such protocols ?
 General view
 DNP3
 C37.118
 OPC
 IEC 61850
 IRIG-B

3. Why such protocols ?
 Traditionally
 Power generated by small number of large power stations
 Flows on distribution network are one way : from producer to consumer
 Smart grids
 Decentralizing energy generation (renewable)
 Optimizing distribution (capacity, efficiency)
 Offering better consumer service (reliability)
Add ICT (Information and Communications Technologies) to the network, in order
to allow the communication between « smart » devices

4. Why such protocols ?
 Cost effective infrastructure
 Communication buses instead of point to point connections
 Interoperability
 Bigger amount of data
 Easier data exchange betweed IEDs
 Data exchange between manufacturers
 Configuration & flexibility
 Data can be centralized or scattered
 IEDs can be reconfigured without affecting infrastructure
 Long term
 Future evolutions made easier
 Follow improvements in communication protocols technology and customers
requirements

5. New protocols and interoperability

6. DNP3
Overview
 IEEE Standard for Electric Power Systems Communications:
Distributed Network Protocol (IEEE Std 1815TM-2012)
 Achieve interoperability between substations and master
stations for the electric utility, water, transportation and gas
industries

7. Typical DNP3 diagram
IED : Intelligent Electronic device
RTU : Remote Terminal Unit
EMS : Energy Management System

8. DNP3 applications
 Intelligent Electronic Devices (IEDs)
 Can report measurements and status from the electrical
network
 May be responsible for controlling devices on the electrical
network
 SCADA systems and Control Centers, DMS and EMS systems
 End user can monitor the network and take required actions

9. DNP3 features
 Can report/control data of more than 200 IEDs
 Bi-directional (report data and control devices)
 Support both polled and unsolicited modes
 Support analog and digital data types
 Event oriented data reporting
 High data integrity
 Configurable scan period to detect data changes
 Configurable event buffer size

10. C37.118
Overview
 IEEE Standard for Synchrophasors for Power Systems:
C37.118 (IEEE C37.118TM-2005)
 Covers synchronized phasor measurements used in electric
power systems

11. Typical C37.118 diagram
PDC : Phasor Data Concentrator

12. C37.118 / PMU applications
 Phasor Measurement Unit simulation for wide area
measurement and control.
 Data acquisition for Power System Automation
 Power system automation, as in smart grids
 Load shedding and other load control techniques as demand
response mechanisms
 Increase reliability of the grid by detecting faults
 Prevention of power outages
 Analysis and correction of sources of degradation

13. C37.118 / PMU features
 Can handle 128 phasor inputs (128 magnitudes & 128 angles),
128 analog inputs and 128 digital inputs
 GPS synchronization (with Spectracom Tsync bus-level-timing
board)
 Supported protocols : TCP, UDP
 Configurable nominal frequency (50 or 60 Hz)
 Configurable data reporting rate
 Timestamp resolution given by the model step size
 Number of simulated PMU limited by network card throughput,
model step size and core resources

14. OPC
Overview
 1996 : Object Linking and Embedding (OLE) for Process Control
 Since Nov 2011 : « Open Platform Communications »
 Designed to provide a common bridge for process control
devices from different manufacturers

15. Typical OPC diagram

16. OPC applications
 HMI : Panorama, PCVue, WonderWare
 SCADA, control systems, EMS, DMS
 PowerFactory, DigSilent, ETAP, …
 Simulation of a large network with a
number of conventionally controlled
generation units together with a
fuzzy-controller implemented at a specific
plant

17. IEC 61850
Overview
 Sampled Values (IEC61850-9.2-LE): digital communication
interface implementation to non conventional instrument
transformers
 GOOSE provides a fast and reliable mechanism of transferring
event data over entire substation networks

18. Power system IEC 61850

19. Typical IEC 61850 diagram

20. Power system IEC 61850
Features
 Support of Sampled Values Publisher/Subscriber
50Hz – 60 Hz / 80 samples per cycle
 GPS time stamping for Goose messages and SV synchronization
 Several data types supported within Goose message (boolean, (un)signed
integer, float 32/64, structure)

21. IRIG-B
Overview
 Inter-Range Instrumentation Group, US organization which defines standards
for time coding
 IRIG-B : pulse rate is 100 PPS (10 ms)

22. Typical IRIG-B diagram

23. Typical IRIG-B diagram
Features
 Spectracom TSync PCIe board
 Synchronized timecode reader/generator
 Generates external signal synchronized with model calculation step time
 40 ns pulse width

24. Other specific communication protocols available
 CanOpen communication protocol for Woodward valve controller simulation
 Foundation Fieldbus H1 communication protocol for sensor simulation
(Temperature, Pressure sensors …)
 Reflective Memory (RFM) using Dolphin high-speed communication boards
 FlexRay to govern on-board automotive computing. Faster and more reliable
than CAN (Controller Area Network)
Next …
 AFDX - data network for safety-critical avionic applications
 Ethercat - open high performance Ethernet-based fieldbus system
 Gateway protocol converter (IEC101-104, IEC61850-MMS, …)

25. Thank you !
Questions ?