Smarter Grid Operation and Control: Smarter Grid Operation and Control: Smarter Grid Operation and Control: Smarter Grid Operation and Control:

Challenges and Future Direction Challenges and Future Direction Challenges and Future Direction Challenges and Future Direction

George Stefopoulos, Bruce Fardanesh

New York Power Authority

Advanced Energy 2011

October 12-13, 2011

Buffalo, NY, USA

Outline

� Introduction

� Power system operation and control

� Current smart-grid challenges and

development

� Conclusions and future research direction

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Notions of Smart Grid

� Distribution/Customer level (not much control and

intelligence until now)

� Smart metering

� Intelligent appliances

� Home area network (HAN)

� Energy efficiency

� Load control/Demand response

� Distributed generation

� Bulk power system level (control and intelligence already

existent)

� Phasor measurement units

� Wide-area situational awareness

� Wide-area coordinated real-time control

� Integration of renewable resources

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Power System Operation and Control

� Local fast control

� Generating unit automatic controls

� Protective relaying

� Control actuators

� Wide-area operations control

� System-wide secondary monitoring and control

� Control center applications

� System state estimation

� Security assessment

� Decision making for optimal operation

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Power System Operation and Control

� Local fast control

� Local measurements/communications

� Primary response to system transients

� Wide-area operations control

� Slow wide-area control

� System-wide SCADA measurements and wide-area

communications

� Power system analysis algorithms

� Decision making tools

� Response to system steady-state conditions and slow

transients

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Relying on Margin

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Uncertainty in Limits

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Crisp Limits

Voltage Stability Limit

Transient Stability Limit

On-Line (Dynamic) RatingInexpensive Limit Enhancer/Remover

On-Line Fast Security AssessmentIncreased Confidence in Models

System-Wide Automatic CoordinationIntelligent Tools to Advise Operators

Iden

tify

Tru

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imit

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ile M

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Cri

teri

aThermal Limit

Actual Operating Limit

Ideal Control Scenario

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PowerInjection & Flow Control Action

Measurements

System Central Controller

Model-BasedTrajectory Planner/Control Action Calculator

Power SystemLimits & Security Criteria

Economic and Other Objectives

System Topology & State Estimator/System Model Update

Area i

Area jArea k

How Feasible?

Limitations and Challenges

� Increasing system complexity (new technologies,

renewable resources, distributed generation,

energy storage, power markets, energy

transactions, etc)

� Structural: Geographically distributed nature

� Communications/Synchronization

� Large-scale systems/Large data sets

� Computing efficiency

� Control bandwidth

� Adequacy of control equipment

� Infrastructure

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Future Direction Components

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System-Wide Automatic

Closed-LoopControl

ComputationalSpeed

What is Needed

� Hardware

� Fast-acting active/reactive injection/absorption and flow

controllers including fast-dynamics generators and/or

electric energy storage devices

� Adequate highly-reliable less-expensive power electronic

controllers

� Abundant highly reliable high-bandwidth communication

networks—Most preferred is dedicated fiber optics

� HV solid-state or power electronics based breakers for

increased stability

� System-wide synchronous measurements for robust and fast

system state and parameter solution/estimation (phasor

measurement units)

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What is Needed

� Algorithms and fast computing

� Criteria for selection of feedback quantities for coordinated

closed-loop power injection/flow control

� Determination of appropriate response rates of closed control

loops

� Robust, adaptive, high-bandwidth control algorithms for large-

scale structurally distributed dynamical systems

� Faster computation capability to approach real-time optimization,

coordination and control

� Proven robust hierarchical control algorithms to overcome the

limitations in achieving wide-area integrated centralized

controller performance

� System/equipment model identification and validation tools

� Faster algorithms for system topology and state

solution/estimation

� Parallel algorithms and faster computers

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Conclusions and Future Direction

� Currently power system operation is based on slow system control

that relies on conservative operating margins. This operating

model may not be adequate in accommodating future challenges.

� Future development needs:

� Accurate measurements

� Fast communications

� Advanced processing capabilities

� Effective control devices

� Phasor technology is the driving force of smart-grid applications

at the bulk power system level

� Potential for closed-loop wide-area control of power systems

� Framework for an autopilot-type fully automated power system

operation

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Questions?

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