© PROMOTioN – Progress on Meshed HVDC Offshore Transmission Networks

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 691714.

Grid forming converters for Black-Start

WP11 Workshop on Harmonisation

19/06/2020

Prof. Ramon Blasco-Gimenez – rblasco@upv.es – Universitat Politecnica de Valencia – Spain

Prof. Nicolaos Cutululis – niac@dtu.dk – DTU - Denmark

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PROMOTioN WP3 ◦ WTG – Converter Interaction

WP3 Partners

Outline

• Introduction: Black Start from Off-shore Wind

• Offshore Wind Black-start Alternatives

• Validation of Grid Forming Control for Black-Start

• Lessons Learnt

• Conclusion

3

Recent Blackout in Tenerife (Canary Islands)

4

• Black out with 40% renewables

• Restoration with gas turbines

Suitability for Black Start Operation

OWPP are large and connected to

substations where grid is

reasonably strong = close to

traditional generators

OWPP can start much faster than

traditional black-start units

5

Suitability for Black Start Operation

OWPP are large and connected to

substations where grid is

reasonably strong = close to

traditional generators

OWPP can start much faster than

traditional black-start units

Goals:

- Achieve “Green Black-Start” from Wind Power Plants

- Allow Wind Power to be “black-start friendly” so it can be

connected earlier in the restoration process

6

Outline

• Introduction: Black Start from Off-shore Wind

• Offshore Wind Black-start Alternatives

• Validation of Grid Forming Control for Black-Start

• Lessons Learnt

• Conclusion

7

Option 1. Grid Forming WTGs - Sequential8 MW 8 MW8 MW

2km 2km 2km

8 MW 8 MW8 MW

2km 2km 4km

8 MW 8 MW8 MW

2km 2km2km

66kV

8 MW 8 MW8 MW

2km 2km 2km

8 MW 8 MW8 MW

2km 2km 4km

8 MW 8 MW8 MW

2km 2km2km

66kV

8 MW 8 MW8 MW

2km 2km 2km

8 MW 8 MW8 MW

2km 2km 4km

8 MW8 MW

2km2km

66kV

BLOCKLOAD

One side shunt compensation

400kV220kV220kV66kV

220kV /75km

8 MW 8 MW8 MW

2km 2km 2km

8 MW 8 MW8 MW

2km 2km 4km

8 MW8 MW

2km2km

66kV

8 MW 8 MW8 MW

2km 2km 2km

8 MW 8 MW8 MW

2km 2km 4km

8 MW8 MW

2km2km

66kV

8 MW 8 MW8 MW

2km 2km 2km

8 MW 8 MW8 MW

2km 2km 4km

8 MW8 MW

2km2km

66kV

BLOCKLOAD

ADJACENT ISLAND

400MW

30MW

Off-shore

substation

On-shore

substation

Main Issues:

- HVAC cable and transformer energisation

- Response to load transients (electrical,

mechanical)

- Fault response and recovery

8

OWPP Voltage

OWPP Current

Option 2: Grid Forming WTGs – Soft Start8 MW 8 MW8 MW

2km 2km 2km

8 MW 8 MW8 MW

2km 2km 4km

8 MW 8 MW8 MW

2km 2km2km

66kV

8 MW 8 MW8 MW

2km 2km 2km

8 MW 8 MW8 MW

2km 2km 4km

8 MW 8 MW8 MW

2km 2km2km

66kV

8 MW 8 MW8 MW

2km 2km 2km

8 MW 8 MW8 MW

2km 2km 4km

8 MW8 MW

2km2km

66kV

BLOCKLOAD

One side shunt compensation

400kV220kV220kV66kV

220kV /75km

8 MW 8 MW8 MW

2km 2km 2km

8 MW 8 MW8 MW

2km 2km 4km

8 MW8 MW

2km2km

66kV

8 MW 8 MW8 MW

2km 2km 2km

8 MW 8 MW8 MW

2km 2km 4km

8 MW8 MW

2km2km

66kV

8 MW 8 MW8 MW

2km 2km 2km

8 MW 8 MW8 MW

2km 2km 4km

8 MW8 MW

2km2km

66kV

ADJACENT ISLAND

BLOCKLOAD

400MW

30MW

Off-shore

substation

On-shore

substation

9

Option 3: HVDC connected WPPs

10

Outline

• Introduction: Black Start from Off-shore Wind

• Offshore Wind Black-start Alternatives

• Validation of Grid Forming Control for Black-Start

• Lessons Learnt

• Conclusion

11

Validation based on

simulations: Generic Controllers

Vendor Specific Controllers

Requirements

Grid Forming WTG/WPP Control Validation

ScenariosHVAC, HVDC

Test cases

12

Simulation Real Time CHiL Real Time PHiL

Voltage control capability, frequency control

capability, fault behaviour, block load, harmonics,

etc.

Mainly adapted from NGET, Elia, but some of them

left loosely defined on purpose to find limits of grid

forming technical capability

Validation based on

simulations: Generic Controllers

Vendor Specific Controllers

Requirements

Grid Forming WTG/WPP Control Validation

ScenariosHVAC, HVDC

Test cases

WTG

Power Hardware in-

the-loop

1 MW WTG converter

Validation based on Real Time Simulation

WTG

Control Hardware in-

the-loop

Multiple WTG

Control Hardware in-

the-loop

Multiple WTG+WPP

Control Hardware in-

the-loop +

protection relays

WP3 (Finished)

WP16(On-going)

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Lessons Learnt

•Both generic and vendor specific controls have been validated.

•With adequate requirements, Black Start operations can be carried out

with partial or small modification to existing WTG converters. (Although

control is very different -> new certification process).

• Local WTG storage might be required.

•Sequential start might lead to overvoltage/overcurrent due to inrush

currents, ferromagnetic oscillations and takes a relatively long time. Can

be done with careful studies and tests (POW might be required).

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Lessons Learnt• Soft start leads to much faster energization time and minimises inrush

current and oscillations.

• Fault recovery is very important with a large number of grid forming

WTGs/WPPs, particularly if both grid forming and grid following WPPs are

considered. Additional grid forming capacity might be needed for fault recovery.

• Grid forming control has to be robust to:

• Large changes in grid resonant peaks

• Interaction with other converters/generators in the same area.

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© PROMOTioN – Progress on Meshed HVDC Offshore Transmission Networks

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 691714.

Conclusions

Grid Forming Wind Power Plants can contribute to speed up system restoration…

… but need to align technology development,technical requirements and business model.

© PROMOTioN – Progress on Meshed HVDC Offshore Transmission Networks

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 691714.

Next workshops/webinars

24-7-2020: Demonstration of Wind Turbine Grid Forming Controller Hardware-in-the-Loop testing for black-start operation

August - September: North Sea Grid for the European Green Deal

Info/registration: https://www.promotion-offshore.net/news_events/calendar/

Further information

PROMOTioN DELIVERABLE D3.7 “Compliance evaluation results using

simulations Part I: WPP/WTG control for Self-Start and Black Start”

https://www.promotion-offshore.net

18

Disclaimer and Partners

PROMOTioN – Progress on Meshed HVDC Offshore Transmission

Networks

MAIL info@promotion-offshore.net WEB www.promotion-offshore.net

The opinions in this presentation are those of the author and do not

commit in any way the European Commission

PROJECT COORDINATORDNV GL Netherlands B.V.

Utrechtseweg 310, 6812 AR Arnhem, The Netherlands

Tel +31 26 3 56 9111

Web www.dnvgl.com/energy

CONTACT

PARTNERSDNV GL Netherlands B.V., ABB AB, KU Leuven, KTH Royal

Institute of Technology, EirGrid plc, SuperGrid Institute,

Deutsche WindGuard GmbH, Mitsubishi Electric Europe B.V.,

Affärsverket Svenska kraftnät, Alstom Grid UK Ltd (Trading

as GE Grid Solutions), University of Aberdeen, Réseau de

Transport d‘Électricité, Technische Universiteit Delft, Equinor,

TenneT TSO B.V., Stiftung OFFSHORE-WINDENERGIE,

Siemens AG, Danmarks Tekniske Universitet, Rheinisch-

Westfälische Technische Hochschule Aachen, Universitat

Politècnica de València, SCiBreak AB,

Forschungsgemeinschaft für. Elektrische Anlagen und

Stromwirtschaft e.V., Ørsted Wind Power A/S, The Carbon

Trust, Tractebel Engineering S.A., European University

Institute, European Association of the Electricity

Transmission & Distribution Equipment and Services

Industry, University of Strathclyde, Rijksuniversiteit

Groningen, MHI Vestas Offshore Wind AS, Energinet.dk,

Scottish Hydro Electric Transmission plc, SCiBreak AB

Ramon Blasco-Gimenez

rblasco@upv.es

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