Towards a Distributed, Towards a Distributed, Service-Oriented Control Service-Oriented Control Infrastructure for Smart Infrastructure for Smart GridGrid

ASU - Cyber Physical Systems LabProfessor G. FainekosPresenter: Ramtin Raji Kermani

Muhammad Umer Tariq1, Santiago Grijalva, Marilyn Wolf

Department of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, USA.

Some Background …Some Background …

What is Smart Grid?◦A smart grid is a digitally

enabled electrical grid that gathers, distributes, and acts on information about the behavior of all participants (suppliers and consumers) in order to improve the efficiency, importance, reliability, economics, and sustainability of electricity services. (Wikipedia)

AbstractAbstract

What is missing?Smart Grid initiatives aim to

overlay the existing power grid infrastructure with a communication and computation infrastructure to enable integration of renewable resources and increased efficiency and reliability of the electric power grid.

AbstractAbstract

Enable integration of renewable energy Increased Efficiency Reliability

Smart GridInitiative

OverlayCommunicationInfrastructure

ComputationInfrastructure

+Electric Power Grid

How?- Substantial changes to Centralized Control Infrastructure- More Powerful Comm. and Comp. Infrastructure

In This Paper …In This Paper …We describe: The elements required for implementation of a

“Prosumer” based distributed control architecture for smart grid.

We propose:

A Hard Real Time enabled, Web Services based1- Computing infrastructure2- Distributed Control infrastructure

For Development For Operation

In This Paper …In This Paper …Main components of this computing

infrastructure: ◦ Generic Real Time API (Generic RT-API) ◦ A Rule based Configurable API Translator◦ A Hard Real Time Web Services (HRT-WS) Engine ◦ The ability to receive XML based configuration/control

instructions remotely.

We have used LXRT/RTAI based Hard Real Time Linux environment.

In This Paper …In This Paper …Keywords:Smart Grid, Cyber Physical Systems,Power System InformaticsHard Real-Time SystemsWeb ServicesModel Transformation

IntroductionIntroduction Energy Management Systems (EMS)

Traditionally, the control of the bulk electric power grid has been realized by Energy Management Systems (EMS) that allow control devices located at substations, generation units and loads to achieve safe and economical operation of the grid.

Main components of these EMS systems:◦ Supervisory Control and Data Acquisition (SCADA)◦ Computing Resources,◦ User Interface◦ Network Economic◦ Security Application Software

Distributed management System (DMS)◦ Increased automation level compared to EMS

IntroductionIntroduction EMS and DMS Based on Centralized Control

Limitations of Centralized Control:◦ Too much data is needed for operation◦ Communication bottlenecks◦ Intractable control & optimization problems◦ Exponential growth of EMS and DMS complexity◦ Vulnerability of energy control centers to security

attacks Also EMS/DMS:

◦ Bad software stack◦ Introduction of More software for power applications

◦ Suitable software engineering techniques.◦ Ensure the fulfillment of mission critical requirements

IntroductionIntroduction Transition towards Distributed Control Architecture

Needs: Appropriate Computing and Control infrastructure

Using Web Services and Service Oriented Architecture?

smart grid applications would require enhancements to the current Web Services infrastructure, such as support for Timeliness

Proposed Computing Structure in this paper:- Development Support- Run-time Support

IntroductionIntroductionContributions of this paper:

◦ A Futuristic distributed control architecture for Smart Grid built on the concept of “Prosumer”.

◦ A Hard Real Time-enabled, Web Services based Computing Infrastructure required to implement our proposed distributed control architecture

◦ Implementation steps towards a lab prototype of the proposed computing infrastructure

Related WorkRelated WorkSmart grid Architecture

◦ Some works support just one type of apps

◦ Some don’t support a generic infrastructure

◦ The Smart Grid initiative of the National Institute of Standards and Technology (NIST) is developing standards to ensure interoperability of the smart grid components

Related WorkRelated WorkOur Architecture represents an

abstraction layer which hides the NIST Conceptual Reference Model and GWAC interoperability stack from smart grid applications and presents them with an interface which is more suitable to realizing flexible and reliable smart grid applications

Related WorkRelated Work

NIST Conceptual Reference Model

Related WorkRelated WorkService Oriented Architecture

◦ Web Services has emerged as the most popular technology for developing SOA based solutions

◦ SOA is not just a set of standards. It is a design philosophy which aims at developing systems that are loosely coupled, flexible, reusable and adaptable. Our proposed infrastructure moves the concepts of Web Services and SOA beyond the enterprise domain and applies them to the development of a smart grid control infrastructure.

Concept of “Prosumer”Concept of “Prosumer”

Prosumer: Producer + Consumer◦ Prosumer may consist of a combination

of: a) components: energy sources, loads, and storage, b) an electric grid, c) a grid control system, and d) a market

◦ Any electric system can be represented as a prosumer, and all the power system control interactions can be modelled as interactions between prosumers

Proposed Control Proposed Control ArchitectureArchitectureArchitecture level◦ 4 (hierarchical) Control Layers◦ Interactions are defined based on interfaces

Proposed Control Proposed Control ArchitectureArchitectureProsumer Services and

Interfaces◦ We use the concept of Prosumer and its

associated control layers to propose a Web Services-based SOA control infrastructure for smart grid by standardizing a set of entity-centric web services.

Proposed Control Proposed Control ArchitectureArchitecture

Proposed Control Proposed Control ArchitectureArchitectureThe details of power system quantities

like voltage, active power and reactive power are contained inside the messages used in the service definitions above.

For example, giveRealTimeStatusMsg of LCTRL service would include all the real time status values that are of interest to a service trying to control that particular device. Moreover, we propose to modify the traditional WSDL definition to associate a timing constraint with each of the operation

Proposed Control Proposed Control ArchitectureArchitectureCase Study: Residential Demand Response◦Utility U_PRSMR◦Neighbourhood N_PRSMR◦Home H_PRSMRHow it works?

Proposed Control Proposed Control ArchitectureArchitecture- Advantages:

- Autonomous Local Control- Smaller Optimization Problems- Automated Configuration and Operation- Reliability and Certification- Flexibility for Market Innovations

IMPLEMENTATION REQUIREMENTS OF IMPLEMENTATION REQUIREMENTS OF PROPOSEDPROPOSEDDISTRIBUTED CONTROL ARCHITECTUREDISTRIBUTED CONTROL ARCHITECTURE

◦Location of Computing resources LCRTL Devices

◦Prioritizing Applications◦Supporting different data rates◦Timelines◦Model driven Development and

operation

Proposed computing Proposed computing infrastructureinfrastructure

◦Hardware Heterogeneous hardware (Servers to

embedded)

◦Operating System RTAI (Real-time Application Interface) (Kernel) LXRT (Linux Real-time) (User Space)

◦Generic RT API and API translator Generic Real-time API Rule-based Configurable API translator

◦Middleware Hard Real-Time Web Services (HRT-WS)

Engine

Proposed computing Proposed computing infrastructureinfrastructure

Program Structure using the Generic RT-API

Once we have a program in terms of our Generic RT-API, we can translate it to a particular RTOS platform using an API Translator

Proposed computing Proposed computing infrastructureinfrastructure

Proposed computing Proposed computing infrastructureinfrastructure

Proposed computing Proposed computing infrastructureinfrastructure

Steps towards Steps towards Implementation Implementation We propose to use model driven tools to transform

model based simulations into actual machine readable configurations for the individual elements of computing platform proposed here, in an automated and reliable manner.

Analogy: Simulink model for Automotive industry Executable Code

generation

Steps towards Steps towards Implementation Implementation

Conclusion and Future Conclusion and Future WorkWorkThe proposed hard real time enabled, Web

Services based automatically configurable computing infrastructure can support and accelerate the application development for the Prosumer- driven, distributed smart grid control architecture.

The scope of the paper is at the architecture level which will open multiple opportunities for research in future.

How this paper could be useful in our How this paper could be useful in our Lab?Lab?

More Questions?More Questions?

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