SMA Solar Technology - emmos.org

SMA Solar Technology

Solar Integration Technology

Presented by Elie Nasr

Business Development, Utility Scale

2

SMA America – Confidential

Disclaimer

IMPORTANT LEGAL INDICATIONS

This presentation is not an offer or invitation for the subscription, takeover or other acquisition of financial instruments issued by SMA Solar

Technology AG (the "company") or by a present or future subsidiary of the company (together with the company, the "SMA Group"). It does not

represent a component of such an offer, nor should it be considered as such. This presentation or parts of it should not serve as the foundation or

reference document for contracts or any obligation to acquire or subscribe to financial instruments of the company or of a member of the SMA

Group.

All information in this presentation was prepared with due diligence. Nevertheless, we guarantee neither the absence of errors nor its

completeness, and nothing in this presentation should be regarded as constituting such a guaranty.

The information contained in this presentation is continually complemented, edited and updated. Some of the statements in this presentation may

be statements about expectations regarding the future, or other statements directed toward the future, which are based on the management's

present perspectives and assumptions, which are subject to known and unknown risks and uncertainties. The actual results, events and

performance of the company can differ considerably from the statements made in the presentation, all of which can be a result of certain factors,

changes in the business and market conditions and changes in the growth opportunities predicted by the management. These and other factors

can influence negatively the financial results of the plans and events described in the presentation. The company assumes no obligation to update

or edit statements regarding the future based on new information or events. The statements regarding the future in this document should not be

considered to be completely reliable, since they relate only to the point in time in which the presentation takes place.

This presentation serves the sole purpose of providing information and may not be disseminated further nor may it be passed on to third parties

which are not its intended audience. No portions of the presentation may be copied, reproduced or quoted by the intended audience for purposes

other than its intended use.

The present document does not represent an offer for the sale of financial instruments in the United States of America. Financial

instruments may not be offered nor sold without registration or exemption from registration, in accordance with the amended version

of the US Securities Act of 1933.

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SMA Solar Technology

�Founded in 1981

�Headquarters in Niestetal, Germany

�Publicly traded on the Frankfurt Stock

Exchange since June 2008

�Fourteen subsidiaries on four

continents

�More than 4,000 employees

�The oldest and largest supplier of

PV inverters in the world

Company ProprietaryLargest Global Inverter Company

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State RPS

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Utility Types & Installed PV Capacity

as of 12/31/2009

Rank Investor Owned Utilities

(MW-AC)

Municipal Utilities

(MW-AC)

Cooperatives (MW-AC)

1 PG&E (CA) 314.6 LADWP (CA) 16.9 Sulphur Springs Valley Electric Co-

op (AZ)

3.1

2 SCE (CA) 170.6 SMUD (CA) 14.2 Kauai Island Utility Co-op (HI) 2.8

3 NV Energy (NV) 87.9 LIPA (NY) 12.0 Trico Electric Co-op (AZ) 0.6

4 San Diego Gas & Electric (CA) 66.4 SRP (AZ) 8.2 Mohave Electric Co-op (AZ 0.36

5 XCEL Energy (CO) 43.2 IID (CA) 3.7 Graham County Electric Co-op (AZ) 0.35

6 PSE&G (NJ) 42.7 Austin Energy (TX) 2.5 Clay Electric Co-op, Inc. (FL) 0.22

7 FP&L (FL) 30.5 Palo Alto Utilities

(CA)

2.2 Great River Energy (MN) 0.21

8 APS (AZ) 21.5 Turlock Irrigation

District (CA)

1.9 Adams-Columbia Electric Co-op

(WI)

0.044

9 Hawaiian Electric Co (HI) 9.1 Eugene Water &

Electric Board (OR)

1.8 Douglas Electric Co-op (OR) 0.038

10 Portland General Electric (OR) 7.7 City of Santa Clara

(CA)

1.6 Mountain Electric Co-op (TN)* 0.03

Others 70.0 Others 14.5 Others 0.07

Grand Total 864 80 8

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Transmission

Grid

- ˜

- ˜

- ˜

POIHV XFMR

MV XFMR

Inverter AC Output Range

{200V - 480V}Medium Voltage Bus

Range {12.5kV - 34.5kV}

Transmission Bus

≥69kV

:

:

:

:

:

:

:

:

:

:

:

:

Sample PV Generation Plant Single Line Diagram

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PV Generation Characteristics

Inadequate Characteristics

� Non-Dispatchable

� Non-Voltage Regulating

� Non-Frequency Responsive

� Non-Controlled ramp-rate

� Trips-off during voltage fluctuations

� No Stability Models

Required Characteristics

� Dispatchable

� Potential to supply voltage regulation

� Frequency Response

� Power Factor Control

� Ramp-Rate Control

� LVRT

� Stability Models

�Currently PV Market “Regulated” by IEEE1547, UL1741

�Anti-Islanding required, no LVRT

�Large penetration on the Grids need to be “Reliable Penetration”

�NEC Code Limit of 600VDC

�1000VDC of interest for large scale utility installations

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Integrating Renewable Energy – A look at Europe

� Target: Maximum possible percentage of electricity

from renewable energy sources

� European countries introduce Feed-In-Tariffs (FIT).

Force acceptance of PV inverters and guarantee

interconnection access.

� PV plants increase in size from residential, to

commercial to utility plants.

� PV grid connection evolution mimicking wind

� Situation then: Renewable PV generation systems do

not contribute to grid stability

� Expert’s opinion: increasing share of renewable

sources will require new standards for

interconnections

� Example: German MV Directive (6/2008) and French

National Act (4/2008)

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Simplified illustration of grid control using PV plants (medium-voltage grid)

Requirements of New Medium Voltage Directive (Germany)

Source: Erzeugungsanlagen am Mittelspannungsnetz. BDEW, Release June 2008

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Active Power Limitation with Power Reducer Box

�Prevent overload or

congestion

�4 default settings but configurable up to 16 steps. e.g.:

100 % power60 % power30 % power0 % power

�Ramp Configurable % rate increase vs. % rate decrease from 20sec to 60min

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Maintaining Grid Stability: Over Frequency Response

� Reduction of active power dependent on Grid Frequency.

> In Case of Grid Failures

> in Case of Power Surplus

> to avoid Grid Instabilities

� 4% active power reduction / 0.1Hz

� Configurable for 60Hz and various % slopes

50.05 50.2 51.5 f [Hz]

P

PM

50.9

Frequency rise

Power

reduction 28%Power

increase up to MPP

SMA 1000V Inverters Designed for Static and Dynamic Active Power Control


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Grid Support: Reactive Power Supply

� Objective: Maintain stable grid voltage

� Static power factor / reactive power supply defined/required by utility

(SMA Range @ Full Power: cos ϕ = 0.90ind to 0.90cap)

� Dynamic reactive power supply on demand remotely controlled by utility

� Dynamic reactive power supply depending on grid voltage

� Dynamic power factor according to a pre-defined schedule

> Impact on PV inverter and plant design!

lag

gin

gle

ad

ing


� German Market PF Requirement: 0.95 lagging to 0.95 leading at point of common coupling

SMA 1000V Inverters Designed for PF Control and VAR Compensation

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Mathematical Formulation According to Pythagoream Theorem

S apparent power

P active power

Q reactive power

Cos ϕ power factor

tan (phi) = Q/P

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Voltage and Current are linked together

> If current i and voltage v are in phase, a fluctuating but always positive power results -

pure active power.

In the case of a phase shift of 90

degrees between i and v, the

average value of the power is zero -

pure reactive power.

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Adjustable Inverter Current Angle = Adjustable Power Factor

Time

AC Voltage & Currents

COS phi = Power Factor

Sync. Voltage

Current, 100%

Current, 60%

Angle phi at which inverter current is imposed

into a voltage source

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Grid Management in Action

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SMA Inverters Q(V) Characteristic

G d V tg

V A r

Q M a x

Q M a x

V o lN om P 2

V o lW idN om

V A rG raN o m

V o lN o m P 1

V o lW idN o m

Qmin,max, ± 0…..50% of Pmax

VolWidNom 0 to 20% of VGrid-Nom

VolNomP1, P2 Voltage Deadband 1 & 2, 0.8pu to 1.20pu

VArGradNom Reactive Power Gradient( 0 to 10%Pmax/Vinv-nom)

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Grid Support : Low Voltage Ride-Through (LVRT)

> Objective: Stay connected during HV grid disturbances in a manner similar to FERC Order 661-A. Why? To avoid simultaneous shutdown of generation sources.

> Required performance:

> Voltage dip to “0” at utility interconnection point (HV side of the transformer)

> Inverter must stay connected during a grid failure for 150 ms (7.5 cycles for 50Hz systems)

> If within 150 ms voltage is back above Limit 1: stable operation

> If after 150 ms voltage stays below Limit 2 (30% of Vnom): May disconnect from the grid

> If voltage between Limit 1 and Limit 2, then recovery behaviour to be defined by utility interconnected to.

0 150 1.500

100%

70%

Zeit in ms

Zeitpunkt eines Störungseintritts

700

unterer Wert des

Spannungsbandes

3.000

15%

45%

Grenzlinie 1Grenzlinie 2

Unterhalb der blauen

Kennlinie bestehen keine Anforderungen hinsichtlich

des Verbleibens am Netz.

30%

Grenzkurven Spannungsverlauf

U/UcLimit 1 Limit 2

Voltage Characteristic

Time of failure (short circuit)

Lower limit of

voltage range

Below blue line: no requirements for FRT

time [msec]

V/VC


� German Market Low Voltage Ride-Through (LVRT) Requirement

SMA 1000V Inverters Designed to Support LVRT Requirement

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LVRT Or Fault Ride Through – Worldwide

Worst Case?

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LVRT for North America: SMA Inverters Can Support

Courtesy ERCOT Operating Guide

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Grid Stability: Dynamic Stability Models

SMA Inverter Dynamic Stability Models for PSSE Versions, 29, 30, 31, 32 & PSLF Versions 16, 17

SOLAR TECHNOLOGY

Questions?

Elie Nasr

[email protected]

(cell) 518-986-8777

(office) 916-316-5385

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SMA Solar Technology - emmos.org