OPAL-RT RT14 Conference: Real-time simulator for power system studies

The 7th International Conferenceon Real-Time Simulation TechnologiesMontreal | 9-12 June, 2014

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D. Mascarella, H.S. Cheema McGill University

[email protected]

[email protected]

Using a Real Time Simulator for Power System Studies on Distribution Systems Operating Under a Large

Penetration of Embedded Generation


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Global proliferation of embedded generation driven by:De-regulation of the power industry

Technological advancements

Continual push for cleaner energy sources

Significant portion to be distribution-connectedMV < 35 kV

Low SCC

Low X/R ratio

Unconventional PCC requires planning studiesProtection

Power quality

Introduction


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IEEE Standard for Interconnecting Distributed Resources with Electric Power Systems (IEEE 1547) defines Interconnection as

The result of the process of adding a DR unit to an area Electric Power System.

What is an Interconnection?


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ProtectionFault detection techniques for interconnection protection schemes featuring

WTGs and synchronous DGs:- Detecting faults

- Detecting islands

Power qualityAssessment and mitigation techniques for distribution feeders featuring

WTGs for:- Voltage rise

- Voltage flicker

- Transformer in-rush currents

DG interconnection studies


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Fast execution times for computationally intensive simulationsProlonged simulation studies

- Flicker studies

- Controller validation

Hardware-in-loop capabilityTest physical devices

- Industrial relays

- Power quality meters and other measurement devices

Implement communication protocols IEC 61850

Real-Time Simulation – Value Proposition


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3 WANDA real-time simulators Power system studies

- Fast executions

- Hardware-in-loop

- Communication protocols (IEC 61850)

Newly acquired OP4500 simulator Power electronic systems

- Detailed modeling of power switches

- Electric vehicle and motor-drive applications

McGill Real-Time Systems


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Balanced 25 kV rural distribution feeder

Supplies 11 MW, 2.5 MVar load

10 MW wind farm

Distribution Feeder

Zcol

BPCC

120kVSubstation

WTG1

120kV/25kV

Wind Farm

575V/25kV

Zgrid

B1 B2 B3 B4

B11

B10

B13B5 B6 B7 B8 B9 B12

Zcol

575V/25kV

WTGN

B14

SCC X/R ratio

PCC 36 MVA 2.5


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Distribution Feeder – Real Time Model

Zcol

BPCC

120kVSubstation

WTG1

120kV/25kV

Wind Farm

575V/25kV

Zgrid

B1 B2 B3 B4

B11

B10

B13B5 B6 B7 B8 B9 B12

Zcol

575V/25kV

WTGN

STUBLINES

B14

SUB-NETWORK 1

SUB-NETWORK 2

SUB-NETWORK 3


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Voltage Flicker – Definition

Voltage fluctuations in the 0.05 Hz - 42 Hz range that give rise to noticeableillumination changes

Phenomenon is composed of two factors:

Voltage fluctuations (i.e. objective factor)

Human exposure (i.e. subjective factor)

IEC 641000-4-15: Standard for quantifying flicker levels

Case Study: Voltage Regulation & Flicker Mitigation


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IEC 641000-4-15: The IEC Flickermeter standardPst – Short term flicker severity metric (10 minutes)

Plt – Long term flicker severity metric (2 hours)

IEC 61000-3-7: Emission limits for fluctuating installations

Flicker Evaluation & Measurement


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Wind flow and local characteristicsMean wind speed

Wind gusts and turbulence intensity

Blade passing effects (i.e. tower shadow and wind shear)

Wind turbine topology and wind penetrationType of wind turbine and associated reactive power control

Rated capacity of the wind farm

Distribution feeder characteristicsShort circuit capacity

X/R ratio

Load type

Factors Influencing Voltage Flicker


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Flicker studies tend to be computationally expensive 10 minute voltage sampling period

Modeling of the power electronic converter

Numerous simulations scenarios needed for comprehensive results

Tailored modeling based on factors which influence flicker Wind speed profile

Wind turbine model

Proper set of simulation tools Real time simulation

- Computational speed-ups via parallel computing

- Timely flicker assessments

HIL with industrial PQ meters

Simulation Requirements


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Develop, test and evaluate performance of control techniques

Voltage Control

Power Factor Control

Newly developed techniques

Voltage Regulation & Flicker Mitigation Techniques


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Results

200 300 400 500 600 700 800

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1.05

1.1

1.15

Voltage a

t P

CC

(pu)

Time (s)

Unity

Voltage control

Power factor control

200 300 400 500 600 700 800

0.98

1

1.02

Voltage a

t P

CC

(pu)

Time (s)

Voltage control

Voltage control + dynamic Volt/Var

200 300 400 500 600 700 800

1

1.01

1.02

1.03

1.04

Voltage a

t P

CC

(pu)

Time (s)

Power factor control

Power factor control + dynamic Volt/Var

Scenario Pst

Unity power factor 0.2188

Voltage control (Vref = 1pu) 0.1739

Power factor control (0.95 lagging) 0.1762

VC + dynamic Volt/VAR 0.0433

PFC + dynamic Volt/VAR 0.0443

Voltage at PCC (pu) Voltage at PCC (pu)

Voltage at PCC (pu)


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Develop and test advanced fault detection schemes for synchronous DGs.

Based on data-mining techniques

Implement the protection schemes on widely used industrial relays via the hardware-in-loop approach

Case Study: Interconnection Protection


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Islanding

Over-Voltages

Ferroresonance

Loss of Synchronism

Loss of Coordination

Sympathetic Trippings

Why Interconnection Protection is needed?


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Interconnection Protection


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Widely used industry relays

SEL 351R-HQ was connected to the OPAL-RT

Industrial Relays

ABB Relays

SEL Relays

GE Relays


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System Setup


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System Setup

Tripping/Faults Events Information

HMIAcSELerator


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SEL 351R Relay Configuration


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SEL relay is configured using data-mining based decision trees50P, 50Q, 50G elements used

SEL 351R Relay Configuration


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Fault Events – HIL with SEL-351R

LLL Fault LLG Fault

LL Fault SLG Fault


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Virtualizing a distribution system model in real-time has numerous benefits with regard to: Fast execution times and prompt results

Interfacing with physical power distribution network devices

Acquire more industrial relays and test new fault detection strategies, co-ordination methods and interoperability (IEC 61850)

Conclusion and Future Work


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Thank you

Technology

OPAL-RT RT14 Conference: Real-time simulator for power system studies