c-dax: a cyber-secure data and control cloud for power · pdf filec-dax: a cyber-secure data...

C-DAX is funded by the European Union's Seventh Framework Programme (FP7-ICT-2011-8) under grant agreement n° 318708

C-DAX:A Cyber-Secure Data and Control Cloud for Power Grids

Matthias StrobbeiMinds – Ghent University

C-DAX Project

European Commission FP7-ICT-2011-8 call project

• C-DAX: Cyber-secure Data And Control Cloud for power grids

Duration: 01.10.2012 – 19.02.2016 Total budget: 4.315.303 Euro EU-funding: 2.931.000 Euro

Project coordination: iMinds Project website: http://www.cdax.eu

Project partners

C-DAX: A Cyber-Secure Data and Control Cloud , IEEE Symposium, 24 March 2016 2

http://www.cdax.eu/

Context & Cause

Transition to Active Distribution Networks• Multiple actors• Intermittent production patterns• New loads: e.g. EVs• Dynamic load patterns: e.g. caused by demand response services

Need for:• Better protection, monitoring & control in distribution grids• Support of large numbers smart grid applications with diverse

requirements• Efficient & secure communication platforms to transfer the generated data

C-DAX delivers:• Communication middleware based on Information Centric Networking• Real-Time State Estimation of distribution grids using PMUs

C-DAX Communication Middleware

C-DAX: A Cyber-Secure Data and Control Cloud for Power Grids 4

Smart Grid Communication patterns

Smart grid applications require support for diverse communicationmodels:

• 1-to-1: e.g. control messages for specific assets• 1-to-M: e.g. energy offers in demand response schemes• M-to-1: e.g. energy consumption reports in demand response or smart

metering• M-to-N: e.g. multiple charging offers from different charging stations to

multiple EVs• Anycast communication: e.g. receiving an offer for voltage regulation by

any suitable subset of EVs located in a certain area • Asynchronous communication: e.g. EVs can only retrieve/deliver data while

connected to the network


Information centric networks Point-to-point networks

• Producer of information “pushes” data to predefined consumers via explicit point-to-point connections

ICN paradigm• Consumers “pull” or “subscribe to” the data they need regardless of who

produced the information, or when, or where it is stored• Data is collected in “topics”

Advantages:• Inherent security as network and physical locations of hosts are not

exposed (publish – subscribe communication)• Overlay network takes care of managing the connections, optimal

placement of the data within the cloud, resilience• ICN allows in-network management and processing of information, e.g., in-

network caching of frequently used data, aggregation, filtering, rateadaptation, optimal traffic management based on underlyingcommunication infrastructure


C-DAX communication platform

7

Topic-based Communication


Publisher A

Pub/sub middleware

Publisher B

Publisher C

Subscriber 1

Subscriber 2

Subscriber 3

Topic 1

Topic 2

Benefits of decoupling publishers and subscribers• Communication partners do not need to know each other• Asynchronous communication possible• Facilitating extensibility, management and configurability

Data Plane

C-DAX Architecture


Control Plane Resolver(RS)

Data Broker (DB)

Security Server

C-DAX Monitoring/ Management System

Monitor

Control

C-DAX CommunicationPlatform

JoinJoinClient

(Publisher)Client

(Subscriber)

SG applicationdata to be published

SG applicationdata to be consumed

Designated Node (DN)

Designated Node (DN)

Configure

Three Communication Modes

Streaming-based• Publishers continuously send data to DB• Subscribers continuously receive data

from DB

Query-based• Subscriber sends query to message broker• DB returns data matching the query

Point-to-point• Publishers send data directly to

subscribers

Communication modes are set per topic to fit the requirements of the application.


Publisher

DB

Subscriber

Publisher Subscriber

DB

Subscriber

Query

Resilience Concept

Topic data should be highly available• Data is stored on two nodes

Resilience of the infrastructure • Each system component is replicated

physically• Each critical communication path is

divided into A path during failure free operation Alternative path(s) due to failures

Three resilience support levels:


C-DAX cloud

SubscriberPublisher

DN DNDB

DN DNDB

: Path during failure free operation: Alternative paths due to failures: Synchronization

Level Data loss(during

failover)

Data delay(during

failover)

Complexity

L1 Y N Low

L2 N Y Middle

L3 N N High

Security Concept

General security requirements• Confidentiality and integrity

End-to-end security, e.g., IEC 62351• Availability

Prevention of attacks, e.g., DoS attacks, replay attacks, spoofing

Security features of C-DAX• End-to-end security between C-DAX clients• Availability of C-DAX infrastructure• Scalable key management mechanism

C-DAX security rationale• Strong authentication of clients and nodes

based on asymmetric cryptography• Symmetric or asymmetric cryptography for

topic data• Minimal trust in underlying infrastructure

Nodes do not have to trust each other inside C-DAX cloud

Clients do not have to trust C-DAX cloud for guaranteed end-to-end security

• Flexible match of security parameters to requirements of use cases, e.g., data rates, latency, confidentiality, integrity


Publisher DN DB Subscriber

Encode Authenticate Authenticate Decode

SecServKey distributionKey distribution

Data Data Data Data

Support for existing smart grid protocols

Problem• Existing smart grid protocols rely on

bidirectional one-to-one communication, e.g., IEEE C37.118, IEC 61850

• C-DAX provides unidirectional many-to-many communication

• C-DAX provides a unified pub/sub interface for communication

Solution• Protocol adaptation layer translates

between smart grid protocols and C-DAX

Benefits for operators• Hardware and software compliant to

existing standards can be used with C-DAX with little configuration changes

• C-DAX can be transparent for legacy hardware and software

Implementation• Protocol adaptation layer for IEEE C37.118

has been implemented and tested


PMU/Client/Adaptation Layer DN

IP

C37.118

TCP/UDP

C-DAXC37.118

IP

TCP/UDP

C-DAX

C37.118

Domain BDomain A

Inter-Domain Concept

Companies• Define C-DAX domains• Want to exchange information Inter-domain concept necessary

C-DAX DN• Provides access for external subscribers to

C-DAX cloud• Only point of contact for external

subscribers• Triggers authentication and authorization

of external clients• Manages external subscriptions• Forwards data from internal nodes to

external clients External subscribers

• May re-publish received information in own domain

Inter-domain security• DN hides domain’s network• Access from external domains only

allowed through DNs• SecServ of each domain manages

respective rights


C-DAX cloud

RS

SecServ

DB DN Externalsubscriber

C-DAX cloud

: Security signaling: Publish/subscribe signaling: Publish/subscribe data transfer


Comparison with Existing Pub/Sub Architectures

Interesting functions thatcould be ported/re-used:• Security• Dual communication mode• Adapter concept

Real-time state estimation in distribution networks using PMUs


Real-time state estimation in distribution networks using PMUs

Need for better observability of the grid to assure stability, power quality, voltage regulation, etc.

Can be accomplished by installing Phasor Measurement Units (PMUs) for regional/local area measurement, protection and

control

C-DAX platform needs to support the stringent latencyrequirements

C-DAX: A Cyber-Secure Data and Control Cloud 18

Real-time state-estimation (RTSE) of ADNs

Monitoring

Control

Protection

State estimation

Network in normal operation:• Congestion management• Optimal V/P control• Optimal dispatch of DER

Network in emergency conditions:• Islanding detection• Fault identification• Fault location

C-DAX: A Cyber-Secure Data and Control Cloud 19

Field Trial Purpose

• Deploy and validate C-DAX in a MV distribution grid under realistic conditions• Identify power system applications that can run on top of LTE network • Demonstrate that C-DAX + RTSE can help DNOs to better manage their grid

C-DAX: A Cyber-Secure Data and Control Cloud , SUNSEED Workshop 25 March 2015 20

Selected applications• Real-time state estimation• PQ measurements

Field-trial characteristics:• Owner: Alliander• Size: 18 buses (area of 12 km2)• Nominal voltage: 10 kV (phase-to-

phase)• Installed monitoring devices:

10 PMUs (EPFL) and 1 PQ meter (NI)• Adopted telecom: commercial LTE

network (Vodafone)

Field trial setup: BML 2.10 feeder (Arnhem, NL)


Field trial setup: Electrical substations


OS Bemmel: Primary substation

Tuindorp:Secondary Substation(urban area)

Field trial setup: PMU locations


Phasor Measurement Units - Basics


Phasor Measurement Units – The EPFL PMU


- First PMU worldwide specifically designed for ADN operating conditions- Rugged and compact NI-compactRIO enclosure to fit in reduced spaces- First worldwide FPGA-based PMU (high speed and determinism)- Equipped with a ±100 ns (max error) stationary GPS module- Metrologically characterized at Swiss Federal Institute of Metrology (METAS)

- Steady state accuracy: 10 ppm (independently of harmonic distortion)- Measurement reporting latency: 37 ms- Reporting rates: 10-20-50-100-200 fps- IEEE Std. C37.118 class-P compliant

Field trial setup: LTE network


Substation setup


Industrial-grade 4G router

compactRIO-based PMU

0.1 class sensors (Altea)

Field trial setup: Alliander data center


LTE Backbone

PDC Firewall

PDC, RTSE

C-DAX

C37.118

8 co

rexe

on/ r

ed h

at

Alliander LivelabData & Control center

Field trial setup: Alliander data center


LTE Backbone

PDC Firewall

PDC, RTSE

C-DAX

C37.118

8 co

rexe

on/ r

ed h

at

Alliander LivelabData & Control center

SecServ

RDSRS

MonSys

MgmSys

Prim DB Sec DB

DN DN

C-DAX Core

C-DAX

Synchrophasor data latencies (4G network) (1)




Mean Std Dev Max Min Data Loss (%)70.9 ms 8.1 ms 770.5 ms 49.2 ms 0.0053

Synchrophasor data jitter (4G network)


Synchrophasor data latencies (w/ & w/o C-DAX)


Phasor Data Concentrator (PDC)


Real-time State Estimation (RTSE)


Definition:“Process of estimating the network state (i.e., phase-to-ground node voltages) with an extremely high refresh rate (typically of several tens of frames per second) enabled by the use of synchrophasor measurements.”

Related applications: Soft-real-time: Optimal V/P control, Congestion management, etc. Hard real-time: Fault detection and locationAdopted method: “Discrete Kalman Filter with online assessment of the model error covariance

matrix”

Estimated vs. measured voltage profiles


Conclusions

One communication platform for heterogeneous applications which is resilient, secure, scalable and flexible and supports legacy protocols

The C-DAX field-trial is unique in the world in that it is the first time that a PMU-based RTSE is deployed in a DNO’s live operated MV distribution feeder, over a public LTE communication network

The higher accuracies and refresh rates of the proposed PMU-based RTSE system has demonstrated to considerably improve the quality of service provided by a DNO by supporting a considerable amount of existing power-system applications


Contact

www.cdax.eu

Thank you for your attention!Questions?

Matthias [email protected]

Thank you.

C-DAX: A Cyber-Secure Data and Control Cloud , SUNSEED Workshop 25 March 2015 42

mailto:[email protected]

c-dax: a cyber-secure data and control cloud for power · pdf filec-dax: a cyber-secure data...

Documents