15.10.2018 | FB 18 | Institute SRT / PE | Alexander Sauer | 1

LEA

Stability of distribution grids with storage, generation units and

comsumers mainly coupled through power electronics

StabLe

Grant No.: 0324101A

15.10.2018 | FB 18 | Institute SRT / PE | Alexander Sauer | 2

LEA

Research Consortium

[https://www.branchenbuchdeutschland.de

/images/startseite/deutschlandkarte.png]

Start of Projekt: April 2017

End of Project: March 2020

Grant No.: 0324101A

working on Medium Voltage

working on Medium Voltage

working on Low Voltage

working on Low Voltageand Medium Voltage

15.10.2018 | FB 18 | Institute SRT / PE | Alexander Sauer | 3

LEA

Net electricity generation in Germany in 2018

[https://www.energy-charts.de/energy_pie.htm]

15.10.2018 | FB 18 | Institute SRT / PE | Alexander Sauer | 4

LEA

Net electricity generation in Germany in 2018

[https://www.energy-charts.de/energy_pie.htm]

Transition to

Distributed Energy Generation with

Power Electronics and

Replacement of rotating inertias

15.10.2018 | FB 18 | Institute SRT / PE | Alexander Sauer | 5

LEA

Key Scientific Questions

Main question: How does “power electronicization” of networks affect grid stability?

How can power electronics compensate for the reduction of rotating inertias, which will be one of the consequences

of a higher penetration with distributed energy?

What are suitable concepts for control of instantaneous and primary power?

Can the local grid impedance be used in order to stabilize control?

How needs the control design to be? Can a decentralized approach stabilize the grid, even with limited or restricted

communication capabilities?

15.10.2018 | FB 18 | Institute SRT / PE | Alexander Sauer | 6

LEA

Low Voltage Grid – Cigré Reference

Lab Setup with a 3L+N-phase system to analyze control

behaviour under possible conditions (pos., neg. and zero

sequence)

Connected to LV grid (400 kVA / 400 V) at TU Darmstadt

Islanding possible through switch

6 x 16 kVA S120 Siemens Converters

15.10.2018 | FB 18 | Institute SRT / PE | Alexander Sauer | 7

LEA

Frequency and Voltage Control

Preise, Mengen,

Parameter

OP, Parameter

Synchronous Machine Power Converter

efd

|E|, ωPQ-Control

Current Control, PWM,

Impedance EstimationPm,soll

Turbine

Pm

PLL, PQ-Control

P, Q P, Q

State Estimation,

Fault Detection

OP, Parameter

System Level

Power Flow

MPC 1 MPC n

Controller Parameter

Design of PQ-

ControlMarket Maker

Power Flow Planning

Ireference

Iabc

Primary Control

SecondaryControl andOptimizationof Primary Control

15.10.2018 | FB 18 | Institute SRT / PE | Alexander Sauer | 8

LEA

Why Impedance Measurement?

[R. Teodorescu, M. Liserre und P. Rodriguez, Grid converters for photovoltaic

and wind power systems. Piscataway N.J., Chichester West Sussex, Hoboken

N.J.: IEEE; Wiley, 2011.]

Variation of Grid Impedance over the course of the day

[Prof. Dr.-Ing. Holger Borcherding, „Abschlussbericht zum Projekt NENEP: Netzrückwirkungen von Netzpulsstromrichtern im Einzel- und Parallelbetrieb in industriellen und öffentlichen Netzen“, Hochschule Ostwestfalen-Lippe im Labor Leistungselektronik und elektrische Antriebe., Lemgo, Mai. 2011.]

15.10.2018 | FB 18 | Institute SRT / PE | Alexander Sauer | 9

LEA

Medium Voltage Converter Structure

110 kWh / 300 kW Li-Ion

Battery

~840 Wh / 300 kW

Li-Capacitor Storage

Coupled via transformer to

medium voltage grid

Power Sharing dependent

on dynamics

15.10.2018 | FB 18 | Institute SRT / PE | Alexander Sauer | 10

LEA

Medium Voltage Grid – Real grid close to Wolfsburg

Inertia available by utilities

Frequency Stability out of scope

here

Battery Converter acts as grid

supporting storage

Voltage Stability provided by

control of P and Q

Control Strategy has to take State

of Charge into account

15.10.2018 | FB 18 | Institute SRT / PE | Alexander Sauer | 11

LEA

Thank you for your attention!

We are eager to continue reasearch

in partnership with you!

15.10.2018 | FB 18 | Institute SRT / PE | Alexander Sauer | 12

LEA

Participants

Fraunhofer IISBMarkus GeppVincent LorentzAndreas LukaschikThomas Heckel

IAVMichael SchollmeyerLars KochNils FalkeFolkhart Grieger

Siemens CTMartin HergtSebastian Nielebock

TU DarmstadtJutta HansonChristina FuhrDominik MaihöfnerAlexander SauerGerd GriepentrogUlrich KonigorskiBernhard Hammer

Contact

Technische Universität Darmstadt

Institut für Stromrichtertechnik und Antriebsregelung

Fraunhoferstr. 4

D 64283 Darmstadt

Prof. Dr.-Ing Gerd Griepentrog

+49 6151 16 20585

gerd.griepentrog@lea.tu-darmstadt.de

Alexander Sauer, M.Sc.

+49 6151 16 20592

alexander.sauer@lea.tu-darmstadt.de

www.lea.tu-darmstadt.de