smart integration of renewable energy into electrical supply … · 2013-05-06 · smart...

Smart Integration of Renewable Energy into

Electrical Supply Systems

Long Beach, CA, USA, 17th - 21th March 2013

E. Ortjohann, A. Schmelter, N. Hamsic, P. Wirasanti

South Westphalia University of Applied Sciences / Campus Soest, Germany

Long Beach, 21.03.2013 2

Agenda

Status of the Renewable Energy in Germany

Problems and Strategies for Grid Integration

System Architecture and Control Methodology of Smart Inverter

Implementation and Verification of Smart Inverter

Conclusion

Long Beach, 21.03.2013 3

Agenda





Conclusion

Long Beach, 21.03.2013 4

Source: Research of Renewable Energy: http://www.fvee.de, Richtlinie 2009/28/EG Erneuerbare Energien

German Government's Renewable Energy Target

18 % Renewable energy share in total primary energy consumption of

Germany up to 2020

Renewable energy share in the electricity supply system of Germany:

35.0 % up to 2020,

50.0 % up to 2030,

65.0 % up to 2040,

80.0 % up to 2050.


Long Beach, 21.03.2013

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 20110

5

10

15

20

25

30

Po

wer

[GW

]

Year

Photovoltaic

Wind

Installed capacity of grid tied PV systems and wind turbines

5

Source: BMU, Prognos AG


29 G

W

25 G

W

3 G

W

21 G

W

17 G

W

27 G

W

2012

Wind non valid values

PV approx. 7,3 GW


2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 20110

5

10

15

20

25

30

Po

wer

[GW

]

Year

Photovoltaic

Wind

Installed capacity of grid tied PV systems and wind turbines

6

Source: BMU, Prognos AG


29 G

W

25 G

W

3 G

W

21 G

W

17 G

W

27 G

W

2012: distribution grids

Wind approx. 95 %

PV approx. 90 %


2013 2014 2015 2016 2017 2018 2019 20200

10

20

30

40

50

60

Po

wer

[GW

]

Year

Biomass 9.3 GW

Photovoltaic 39.5 GW

Wind 55.0 GW

7

Estimated electrical capacity of RES in Germany up to 2020

approx. 110 GW

Source: BEE Branchenprognose2020


Long Beach, 21.03.2013 8

Offshore wind development

Source: http://www.bard-offshore.de/

Alpha Ventus:

12 turbines

60 MW Source: http://www.alpha-ventus.de/

Baltic 1:

21 turbines

48.3 MW

Source: http://www.enrw.de

BARD Offshore 1:

80 turbines

400 MW (2013)



2011

7,7 %

of electricity

demand

47 TWh

2020

25.0 %

of electricity

demand

150 TWh

9

Repowering is already in process

Goals of Germany:

Halving the number of wind turbines

Double the installed wind power

Triple the electricity generation related to 2011

Source: http://www.wind-energie.de/ (recalculated for 2011)


Long Beach, 21.03.2013 10

Agenda





Conclusion

Long Beach, 21.03.2013 11

Conventional power systems


Un

idire

ctio

nal su

pp

ly p

roce

ss

Active

Controlled Area

Passive

Controlled Area

3~

...

...

Pumped

Hydro

Grid

220 kV / 380 kV

110 kV

10 to 30 kV

400 V

3~

Reginal

Grid

Special

Loads or

Suppliers

Regional

Grid

Special

Loads or

Suppliers

3~

3~

3~

Offshore

Wind

ParkPower Plant

3~

Long Beach, 21.03.2013 12

Moving towards decentralized power systems


Bid

ire

ctio

nal su

pp

ly p

roce

ss

Active

Controlled Area

...

...

Grid

220 kV / 380 kV

110 kV

10 to 30 kV

400 V

3~=

3~=

3~=

3~

3~ 3~

Power Plant

Offshore

Wind

Park

Pumped

Hydro

3~

3~=

3~=

Regional

Grid

Reginal

Grid

3~

3~3~

3~

3~3~

3~

3~3~

3~

3~3~

3~

3~3~

3~

3~3~

3~

Special

Loads or

Suppliers

3~

Special

Loads or

Suppliers 3~=

3~=

3~=

3~

3~3~

3~=

Long Beach, 21.03.2013 13

Transfer of the conventional control schemas into all grid levels

Conventional control schemas of transmission networks must be

extended to distribution networks !

PV-Park

Windpark

Biomasse

Batterie

-

speicher

CHP

CHP

CHP

H

CHP

CHP

CHP

CHP

CHP

Tank-

stelle

Wasserkraft

Kraftwerk

Schalt-

anlage

Fluss

Wasserkraft


Long Beach, 21.03.2013 14

Grid Code for decentralized generators in Germany

Power reduction (supervisory side)

Frequency and voltage droop (unit side)

Fault Right Through (unit side)

Source: VDN, German Grid Code


Long Beach, 21.03.2013 15

Inverter as Flexible Grid Interface for Integration of DERs


Unit Control

3~

=

(~)

GridEnergy Conversion

System (ECS)

3 (4)2 (3)

Load

Load

~~

~~

~~~~

~~

G

3~

Photovoltaic Generator

Wind Power System

Communication

Local

Control

Inverter is the Essential Device for

optimal integration of DERs

Long Beach, 21.03.2013 16

Agenda





Conclusion

Long Beach, 21.03.2013 17

Technical requirements of inverter as grid integration of DERs

DERs integration into Active Network

Symmetrical active network

Asymmetrical active network


=3~

=3~

Long Beach, 21.03.2013 18

Technical requirements of inverter as grid integration of DERs

DERs integration into Passive Network

Symmetrical passive network

Asymmetrical passive network


=3~

=3~

Long Beach, 21.03.2013 19

Inverter feeding modes at grid side (Unit Control)


Inverter Feeding Modes

at Grid Side

Grid Parallel

Symmetrical Asymmetrical Symmetrical Asymmetrical Symmetrical Asymmetrical

Grid Forming Grid Supporting

ECS Driven Feeding Grid Driven Feeding

Long Beach, 21.03.2013 20

Inverter feeding modes at grid side (Unit Control)

Grid forming: f- and V-control with nominal reference values

(grid side driven)

Grid supporting: P- and Q-control with external reference values

from load dispatcher (grid side driven)

Grid supporting: P- and V-control with external reference values

from load dispatcher (grid side driven)

Coupling: Δf/ΔP and ΔV/ΔQ droop (grid side driven)

ΔP/Δf and ΔQ/ΔV droop (grid side driven)

Grid parallel: P- (and Q-) control with reference values from source

(unit side driven)


Long Beach, 21.03.2013 21

Symmetrical grid forming mode inverter



at Grid Side

Grid Parallel




Long Beach, 21.03.2013 22

Symmetrical current control inverter


dq

SVM

-

-

Lf

Cf

V_ref

V_ref

Vd

Vq

Vdc

Id_act

Iq_act

Inverter

=3~

abc

dq

abc

Vejφ

Local

Grid

Grid

Iq_ref

Id_ref

Long Beach, 21.03.2013 23

Symmetrical grid forming mode inverter


dq

SVM

-

- -

Lf

Cf

V_ref

V_ref

Vd

Vq

Vdc

PLL

Id_act

Iq_act

Inverter

=3~

Vref

Vact

-

abc

dq

abc

wact

Vact

wref

Local

Grid

Grid

Long Beach, 21.03.2013 24

Symmetrical grid forming mode inverter with primary control


Qact

Primary Control

-

-

Δw

ΔV

Kw

KV

Pact

P and Q

Measurement

Pref

-

Qref

dq

SVM

-

- -

Lf

Cf

V_ref

V_ref

Vd

Vq

Vdc

PLL

Id_act

Iq_act

Inverter

=3~

Vref

Vact

-

abc

dq

abc

wact

Vact

wref

Local

Grid

Grid

Long Beach, 21.03.2013 25

Symmetrical grid forming mode inverter with primary control


Qact

Primary Control

-

-

Δw

ΔV

Kw

KV

Pact

P and Q

Measurement

Pref

-

Qref

dq

SVM

-

- -

Lf

Cf

V_ref

V_ref

Vd

Vq

Vdc

PLL

Id_act

Iq_act

Inverter

=3~

Vref

Vact

-

abc

dq

abc

wact

Vact

wref

Local

Grid

Grid

Proposed control schemas

fulfill the requirement of

decentralized generators

Grid Code !!

Long Beach, 21.03.2013 26

Asymmetrical grid forming mode inverter



at Grid Side

Grid Parallel




Long Beach, 21.03.2013 27

Asymmetrical grid forming mode inverter


SVM

Lf

Cf

Vdc

Inverter

=3~

wact

Local

GridGrid

Positive sequence

V-ControllerI-Controller

-

-

-

-V1_q

wref

V1_d_ref

wact

V1_d

I1_q

I1_dV1_d

Negative sequence


-

-

-

-V2_q

V2_q_ref

V2_d_ref

V2_q

V2_d

I2_q

I2_dV2_d

Zero sequence


-

-

-

-V0_q

V0_q_ref

V0_d_ref

V0_q

V0_d

I0_q

I0_dV0_d

[ I120_dq_act ] [ V120_dq_act ]

PLL

[ V120_dq ]

Vγ _ref

V_ref

V_ref

γ

120

abc

120

abc

120

Long Beach, 21.03.2013 28

Asymmetrical grid forming mode inverter with primary control


SVM

Lf

Cf

Vdc

Inverter

=3~

wact

Local

GridGrid

Positive sequence


-

-

-

-V1_q

wref

V1_d_ref

wact

V1_d

I1_q

I1_dV1_d

Negative sequence


-

-

-

-V2_q

V2_q_ref

V2_d_ref

V2_q

V2_d

I2_q

I2_dV2_d

Zero sequence


-

-

-

-V0_q

V0_q_ref

V0_d_ref

V0_q

V0_d

I0_q

I0_dV0_d

[ I120_dq_act ] [ V120_dq_act ]

PLL

[ V120_dq ]

Vγ _ref

V_ref

V_ref

γ

120

abc

120

abc

120

Primary Control

ΔV1_d

KV1_d

Kω

KV2_d

KV2_q

KV0_d

KV0_q

ΔwΔV2_d

ΔV2_q

ΔV0_d

ΔV0_q

Q1

P1

Q2

P2

Q0

P0

Pref

Qact

Pact

Qref

-

-abc

120

abc120

-

-

-

-

-

-

P and Q

Measurement

Long Beach, 21.03.2013 29

Agenda





Conclusion

Long Beach, 21.03.2013 30

Developed smart inverter: technical specifications

Total Power 100.0 kVA

2 x Module 12.5 kVA

1 x Module 25.0 kVA

1 x Module 50.0 kVA

Max. Input Voltage 800 V (DC)

Output Voltage 3 x 400 V (AC)

Max. Efficiency 95 %


Long Beach, 21.03.2013 31

50.0 kVA inverter module


Long Beach, 21.03.2013 32

AC Connection module


Long Beach, 21.03.2013 33

Developed smart inverter

50 kVA inverter module

AC Connection module


Long Beach, 21.03.2013 34

Verification of proposed control methodology of smart inverter


=

3 ~

LC

Vdc

25 kVA

LC

=Vdc3 ~

12.5 kVA

Load

Parallel operation of 2 Asymmetrical

Grid Forming with Primary Control

inverters are examined.

Inverter Parameters:

Vdc = 780 V

Vref = 230 V

fref = 50 Hz

Vdroop = 4 %

fdroop = 4 %

Long Beach, 21.03.2013 35

Asymmetrical Grid Forming with Primary Control

Asymmetrical load; RA=20Ω, RB=40 Ω, RC=60 Ω

Load Voltages

Load Currents


Long Beach, 21.03.2013 36

Asymmetrical Grid Forming with Primary Control

Symmetrical load; RA= RB= RC= 16 Ω

Load Voltages

Load Currents


Long Beach, 21.03.2013 37

Agenda





Conclusion

Long Beach, 21.03.2013 38

Conclusion

Characteristics of the proposed smart inverter control architectures:

The introduced control architectures enable reliable, fast and

efficient control of future oriented power systems

Increase the flexibility and adaptability for DERs grid integration

into conventional grids

Support the conventional control schemas, which are consequently

down sized to the low voltage level

Give an opportunity to establish an advance control function down

to local level

Long Beach, 21.03.2013 39

Conclusion

Change the ordinary DERs integration to be a part of the dynamic grid

control and management

Empower and turn distribution network to be the active control area

with Smart Inverter

Local Area

Intelligent Substation

Prosumer

50 kW

==

CHIP

CHIP

=3~

CHIPCHIP

CHIP

CHIP

CHIP

CHIP

3~

=

3~

CHIP

SGCC

Long Beach, 21.03.2013 40

Acknowledgement

This research work is supported by

Long Beach, 21.03.2013 41

Thank You For Your Attention!

Paramet Wirasanti

South Westphalia University of Applied Sciences,

Division Soest

Department of Electrical Engineering

Laboratory of Power Systems and Power Economics

Email: [email protected] 6

7

4

~ ~

~

5

~

2

~

1

~

3

~

Power Plant~

~

~

~

~

~

~

~ ~Virtual

©

smart integration of renewable energy into electrical supply … · 2013-05-06 · smart...

Documents