Research Acvies in

Professor Remus Teodorescu Aalborg University Energy Department [email protected] www.et.aau.dk

December 10, 2012 Aalborg University

Founded in 1974

December 10, 2012 2 Organisaon

December 10, 2012 3 • Power Electronics for Wind Power • Grid Supports with Wind Power Plant • Storage System for Grid Support • Grid Integraon of PV

December 10, 2012 4 Wind Energy Systems

• Record installaon of 41.7 GW (6% increase from 2010) in spite of the financial/economic crisis. • The biggest annual markets in 2011 were China – 17.6 GW, Europe – 10.2 GW,followed by USA – 6.7 GW • The cumulave worldwide installed wind power by end of 2011 was 241 GW • The biggest cumulave market was Europe – 87.5 GW (43.7%) followed by Asia 85.3 GW and USA – 40.2 GW (20.1%) • Offshore installaons mainly in Europe was 470 MW (67.5% reducon from 2010). • The average growth rate for 2012-2016 is 10%. In 2016 510.9 GW cumulave installaon • The worldwide accumulated installed power forecasted by 2021 is roughly 1 TW, leading to a global wind power penetraon of 8%

Power Electronics for Renewable Energy 5 11-Dec-12 Systems Course, Aalborg University Wind Energy Systems development

• is nr. 1 with 12.9% (1.4% drop from 2010) • Four chinese manufacturers are in Top 10 • Danish Vestas and Siemens Wind stand for over 20% of the worldwide market • 2 - 3MW WT are sll the "best seller" on the market! • Averaged size on-shore in 2011 is 1.67 MW and off-shore 3.7 MW • 3 - 7 MW WT are used for off-shore farms, ex. Vestas -8MW, – 6-7.5 MW, Siemens – 6 MW, GE – 4 MW

Power Electronics for Renewable Energy 6 11-Dec-12 Systems Course, Aalborg University Wind PowerWind Turbine Technology Processing Full power converters for WT

• All power goes through the power converter, full speed control • AC-AC decoupling by means of the DC bus • Full acve/reacve power control • Low-voltage ride-through capability • More expensive and lager converter than in DFIG

7 11 December 2012 Full Power Converters Typical layout – large scaleWind Turbine Technology offshore turbine with full power converter PCS 6000Current Developments, Wind Areva Mulbrid M5000/ABB : Key components: From IGCT to a 9MVA Converter Permanent Magnet Pitch Gearbox if used Generator Brake Drive

PM Generator

Mechanical Brake

Pitch Drive

Wind Turbine Controller

Frequency Converter

Converter Controller

Lower section of the tower Generator Grid Side Side Converter Converter Wind Turbine Controller

Line Coupling Power Converter Transformer

Main Transformer

Medium Auxiliary distribution Voltage Switchgear

MV Switchgear 10 33kV, 50 or 60Hz

©ABB Group Group MV – 3,3 kV out November 11, 11, 2011 2011 | Slide | Slide 25 25 Rated power: 5-10 MW Turbine concept:1 stage- Gearbox, variable speed, variable pitch control Generator: MV PMSM Converter: FSC (NPC-IGCT) located at base of tower Market - Offshore

December 11, 2012 8

©ABB Group Group November 11, 11, 2011 2011 | Slide | Slide 27 27 Wind TurbinesWind Turbine Technology Vestas Wind Systems A/S

Vestas V164 off-shore turbine Rated power: 8,000 kW Rotor diameter: 164 m Hub height: min. 105m Turbine concept: medium-speed gearbox, variable speed, variable pitch, full-scale power converter Generator: permanent magnet Prototype: 2013 9 11 December 2012 FloatingWind Turbine Technology Wind Turbines Floating foundation

Semi-submersible multi-megawatt wind turbine Designed by: US Principle Power Allocation: Aguçadoura, Portugal Turbine size: 2 MW (Vestas) (up to 10 MW) Assambled onshore and towed and anchored offshore SEER Workshop 2011 10 11 December 2012 Vestas Power Program 2007 - 2012 power electronics power systems … converter technology and generic control features for … to determine the control and operaonal properes required large turbines in large wind power plants to meet high for wind power plants for opmal integraon in the power system power density, efficiency and reliability targets – 5 PhD using AC or HVDC transmission – 4 PhD

PE 1 - High Power Density PS 1 - Wind Power Plant Control for HVDC Connecon Converter for Large WT PhD Sanjay Chaudhary PhD Osman Senturk Started 1 July 2008 Started 1 July 2008

PE 2 -Control of Grid-Connected Converters for Large WT PS 2 - Wind Power Plant Control for AC Connecon PhD Hernan Miranda PhD Müfit Aln Started 1 July 2008 Started 15 Oct 2009

PS 3 - Power system oscillaon damping with PE 3 - Advanced Control of Grid Connected Converter for LWT augmented Wind Power Plant PhD Ömer Göksu PhD Andzrej Adamczyk Started 15 Oct 2009 Started 1 August 2009

PS 4 - Opmizaon of VSC-HVDC Transmission in WPP PE 4 - Modelling Life Time of Electrical PhD Rodrigo da Silva Components and Systems in WT Started 20 Oct 2009 PhD Crisan Busca Started 1 Sep 2010

PE 5 - High Voltage Power Converter for Large Wind Turbine ES 2 - Storage System for Large WT Penetraon PhD Michal Sztykiel PhD Maciej Swierczynski Started 1 Feb 2011 Started 1 August 2009 … to determine the most suitable storage technology to be used with wind power plants meeng the reliabiliy targets – 1 PhD

December 11, 2012 Slide 11

Thermal Modeling of Press-Pack IGBT 3L- NPC-VSCs for Large Wind Turbines

Problem • Large wind turbines 6MW/3.3 kV • Reliability and power density • Need for electro-thermal models

Soluon • 6MW/3.3 kV NPC with 4.5 kV/1800A PP IGBT • Develop stac an dynamic electro- thermal models taking cooling soluon into account • Simplified dynamical thermal models that can use to define overload capability online

Senturk, O.; Helle, L.; Munk-Nielsen, S.; Rodriguez, P.; Teodorescu, R.; , "Power Capability Invesgaon Based on Electro-thermal Models of Press-pack IGBT Three- Level NPC and ANPC VSCs for Mul-MW Wind Turbines," IEEE Transacons on Power Electronics, January 2012

December 10, 2012 12 High Voltage Power Converter for Large Wind Turbines

Power Systems § Reliability Voltage range: 10 - 220 kV § Modularity Collection Power range: 100 - 1000 MW § G Grid Safety Applications: Power Systems, SVG High Power Generator § Redundancy Topologies: H-Cascaded, MMC, CTL HV Converter Very

Grid-Side Inverter Voltage range: 20 kV Power range: 10 MW Power Application: Wind Turbine Problem MV Drives § Efficiency Topology: ? High Voltage range: 0.69 - 6.6 kV § Size

Power range: 0.3 - 30 MW § Weight • Large wind turbines (10 MW!) Applications: High Power Drives § Cost

Topologies: NPC, ANPC, FC • High repair and maintenance costs Medium Voltage High Voltage Very High Voltage (especially for offshore WTs)

• MV transformer is bulky MMC-13L (PWM-APOD) #1 Cost [pu] • Grid filters - bulky 1 pu #2 .

• Generators 10kV – insulaon . .

1x(4500 V, 360 A) challange #12 IGBT MTBF [pu] Size [pu] 1 pu 1 pu Soluon A • 20kV/10MW transformerless 13L- #1 MMC #2 . . • Reliable PP IGBTs 4.5 kV/340A . Losses [pu] Weight [pu] #12 1 pu 1 pu

M. Sztykiel, R. Teodorescu, S. Munk-Nielsen, P. Rodriguez, L. Helle, C. Busca, “Topology and Technology Survey on Medium Voltage Power Converters for Large Wind Turbines,” Internaonal 10th Wind Integraon Workshop, 25-26 October 2011, Aarhus, Denmark.

December 10, 2012 13 Lifeme Modelling of Press-Pack IGBTs in Wind Power Applicaons

Problem • Large wind turbines (mul-MW) • High repair and maintenance costs (especially for offshore WTs) • Not much experience with PP IGBTs • PP IGBTs more reliable than wire- bonded IGBTs (longer life) • Unequal pressure, current and temperature of individual chips Soluon • MV converters with PP IGBTs • Very high reliability wind turbines • Power cycling tests • FEM model and inside measurement of the individual chip currents and temperatures

C. Busca, R. Teodorescu, F. Blaabjerg, S. Munk-Nielsen, L. Helle, T. Abeyasekera, P. Rodriguez, “An Overview of the Reliability Predicon Related Aspects of High Power IGBTs in Wind Power Applicaons”, ESREF 2011 (22nd European Symposium on Reliability of Electron Devices, Failure Physics and Analysis), Bordeaux, France, 3rd-7th October 2011.

December 10, 2012 14 Advanced Control of the Grid Side Converter for Large Wind Turbines, focusing on Fault Ride-Through for Asymmetrical and Symmetrical Grid Faults Fault 1 (Single Line-to-Ground)

Bus 6 Bus 12 @ Fault location @ PCC @ WTG 1 1 Vc G4 Vc Vb Bus 1 1 Yd1 0.5 0.5 0.5 Bus 4 Va 0 0 0 Va Vc Bus 2 Bus 10 Bus 5 -0.5 -0.5 -0.5 V Va G2 -1 b Bus 9 Vb : For asymmetrical grid faults, posive -1 Problem -1 V Yd1 -1 -0.5 0 0.5 1 -1 c -0.5 0 0.5 1 -1 -0.5 0 0.5 1 G1

Yd1 PCC WTG 1.5 1 negave and zero sequence voltages are 1 Vb 1 YGyg2 YGyg Dyg5 Vc Fault 1 0.5 0.5 0.5 Bus 7 Bus 8 Bus 3 V Fault 2 0 a 0 0

exisng in the grid, where negave sequence Va V -0.5 c Vc -0.5 -0.5 Va YGyg YGyg - Vb Bus 11 1 Vb - 1 -1 -1.5 voltage is harmful for power system elements. 3G -1.5 -1 -0.5 0 0.5 1 1.5 -1 -0.5 0 0.5 1 -1 -0.5 0 0.5 1 Yd1 1 Fault 2 (Single Line-to-Ground) Soluon: For the sake of power system; 0.5 IW abc 0 posive sequence voltage is boosted, negave [pu] -0.5 Ia Ib Ic sequence voltage is reduced, via injecng -1 1 opmum posive and negave sequence V4 abc 0 [pu] currents by Wind Turbines. -1 WPP va vb vc WT set-points TSO Control reference 1.1 1.2 1.3 1.4 1.5 dispatch Problem: There is a need for opmizaon of time [sec]

PCC

Fault Ride-Through for symmetrical low voltage . . . . Feedback WT WT Control Control faults, depending on the operang point of the Grid wind turbines and grid characteriscs. PCC

. . . . WT WT WT Control Control Control Grid Code Soluon: Coordinated Fault Ride-Through of Compliance @ PCC Id & Iq

wind turbines at Wind Power Plant control . . . . WT WT WT output Control Control Control V & f level. feedback “An Iterave Approach for Symmetrical and Asymmetrical Short-Circuit Calculaons with Converter-Based Connected Renewable Energy Sources. Applicaon to Wind Power”, 2012 IEEE Power Engineering Society General Meeng

December 10, 2012 15 Control and Protecon of Wind Power Plant with VSC-HVDC Connecon WTG#1 MV Collector Grid & HV Feeders VSC-HVDC Transmission LCL GSC 33 kV Coll. Filter MV feeder #1 System Problem Bus#1 150 kV Coll Bus #1 V

HV feeder #1 k

MV feeder #2

150 kV 0 7 Faults in the offshore WPP-grid cause 1 Xph1 33 kV Coll. Vc1 Offshore WTG#2 Bus#2 VSC oscillaons in the power-flow and dc- FB WTG#3 33 kV Coll. MV feeder #3 V voltage of the VSC-HVDC. WPP Bus#3 150 kV dc1 Coll Bus #2

generaon is adversely affected. HV feeder #2 ±150 kV, MV feeder #4 1400A, 200km • Detecon and discriminaon of FA HVDC Cable WTG#4 33 kV Coll. Bus#4 faults. Vdc2 V k Onshore Grid 0 7

(Th- Eqvt.) Vg 1 • DC voltage and power-flow 400MW offshore WPP Feeder circuit breaker (CB) Onshore o/c relay current transformer (CT) V VSC k

0 0

oscillaons during asymmetric 4 faults 400MW WPP with VSC-HVDC connecon

Experimental SLG Fault Soluon set-up with RTDS with GTNET- Currents RTDS & Relay GSE & GTAO Cards • Use of over-current relays with REF615 IED IEC-61850 communicaon. State Omicron Amplifier RSCAD OC • Negave sequence current control CMS156 Relay State from the WTGs and the VSC-HVDC. PC with Breaker Open ABB IED RSCAD REF615 & PCM600 Publicaon: “Applicaon of Over-current Relay in Offshore Wind Power Plant Grid with VSC-HVDC Connecon,” in 10th Internaonal Workshop on Large-Scale Integraon of Wind Power into Power Systems as well as on Transmission Networks for Offshore Wind Power Plants. Aarhus, Denmark on October 25 - 26, 2011.

December 10, 2012 16 Losses Minimizaon in MTDC Receiving End Station 1 Receiving End Station 2

DC Cable DC Cable

Grid 1 Grid 2

iAC iAC u iDC iDC u Grid ω,θ Current Current ω,θ Grid PWM PWM Problem Synchronization Controller κ κ Controller Synchronization * v v * iAC DC v * v * DC iAC AC Voltage Reference DC Voltage DC DC DC Voltage Reference AC Voltage Control Generation Control Control Generation Control * P* Droop Droop P* * • v AC v AC Active Active Mulple large off-shore VSI-HVDC Reactive Reactive vAC Power Power Power Power vAC Conreol Conreol Conreol Conreol Q* i v v i Q* plants in North Sea--> MTDC iAC AC AC AC AC iAC Measurements + Measurements + Communication Communication RES #n and TSO #n Sending End Station 1 * * communication link κ1,1,VDC κ2,2,VDC • Power management more flexible Offshore communication link * fc11( ), PAC ,1 • WPP 1 ... Voltage profile not opmized VP, iAC u iDC ON,1 ON ,1 Grid ω,θ Current PWM WPP Synchronization Controller ... MASTER * vAC i vDC CONTROLLER AC VPON,2, ON ,2 AC Voltage Reference DC Power * Soluon Control Generation fc22( ), PAC ,2 * ... v AC VPOFF,1, OFF ,1 Measurements + * Communication • Master MTDC Controller to PWPP opmize voltage profile and minimize losses in DC lines and converters

R. Da Silva et al “Opmizaon of VSC-HVDC Transmission in Wind Power Plants,” in 10th Internaonal Workshop on Large-Scale Integraon of Wind Power into Power Systems as well as on Transmission Networks for Offshore Wind Power Plants. Aarhus, Denmark on October 25 - 26, 2011.

December 10, 2012 17 Power Oscillaon Damping with Wind Power Plant

Problem • IEEE 12-bus grid & mode controllability: • Impact of the large scale wind power generaon on oscillatory B9 B1 B6 B12 performance of the grid B7 B2 B10 B5

• Control method for WPP to B4 - system node B8 contribute to low frequency modes B3 - generator node B11 damping - mode controllability by P Soluon - mode controllability by Q • PSS-like control loop to modulate wind turbine reacve power output • WPP damping control: • RMS mul-bus and mul-machine 1.0015 No PSS Damping rao grid model with relevant WPP WPP PSS 1.001 Mode No PSS WPP_PSS model; small-signal analysis for 1.31 Hz 3.7 % 5.9 % different study cases 1.0005 1.25 Hz 9.3 % 8.6 % 1.04 Hz 3.4 % 4.9 % 1

0.9995 0 1 2 3 4 5 6 7 Adamczyk, A.; Teodorescu, R.; Rodriguez, P.; , "Control of Full-Scale Converter based Wind Power Plants for damping of low frequency system oscillaons," PowerTech, 2011 IEEE Trondheim , June 2011

December 10, 2012 18 Frequency Control with Wind Power Plant df/dt control rate limiter f grid RWPP Pinertia − Pref+ inert HsWPP * Σ Iref I Problem: ⎛⎞P+ jQ 1 WPP 1+ 0.02s Qref ⎜⎟ref ref ⎜⎟ P ⎜⎟Vmeas 1+TsWPP ref V ⎝⎠ • Ineral response from WPPs PCC 1.002 • Providing synchronizing power from WPPs for Vwind=10m/s 1 Derivative Control Temporary Frequency Control 0.998 Soluon: Proposed Control 0.996 )

• u Adapted 12 bus test grid p (

0.994 y c

• n 0.992 Distributed control in WPP e u q

e 0.99 • r Opmal power control with focus to grid F frequency response 0.988 0.986 • Find the methodology for opmal H,R and T 0.984 0.982 for Vwind=10m/s Bus 6 Derivative Control 13.8-15 kV 1.2 TG4 Bus 12 L6 230 kV Temporary Frequency Control G4 Bus 1 345 kV Proposed Control 150 MW 500 MVA 1.15 @0.95 Area 2 P Bus 4 Line 1-6 Line 4-6 Bus 9 300 km 300 km 1.1 (Slack) TG1 C4 ) Bus 5 L4 G1 L5 C5 u

p 1.05

Bus 2 Bus 10 300 MW 200 MVAR ( 750 MVA TG2 L2 100 MW 40 MVAR @0.85 2 G2 @0.9 P

Line 4-5 P 250 MW 50% 1 150 km W @0.9 640 MVA 40% Area 4 P 20% L1 Line 1-2 Line 2-5 Line 3-4 0.95 10% Area 3 (double) 100 km 400 km 5% 300 MW 100 km @0.85 Area 1 P Bus 3 0.9 Bus 8 AT1 Bus 7 AT2 Line 7-8 600 km 0.85 TG3 Bus 11 L3 L7 G3 350 MW 400 MVA 0.8 @0.95 0 5 10 15 20 25 30 -100 MVAR 30% Time (sec) Mufiat Aln, et.al “ Methodology for Assessment of Ineral Response from Wind Power Plants”, PES GM 2012 December 10, 2012 19 Energy Storage Systems

Source: EPRI, “Electricity Energy Storage Technology Options – A White Paper Primer on Applications, Costs, and Benefits”, Dec. 2010

• despite the real need for energy storage systems within the power system, very few grid-integrated storage installaons are in actual operaon in EU and US today; • this landscape is expected to change around 2012, when new energy storage systems are expected to be deployed worldwide, especially in US. Li-Ion baery storage life-me issues for September 8, 2012 Slide 20 power grids Life-Time Models for Li-Ion Baeries in Grid Support Applicaons

Problem • Esmaon of RULfor Li-ion baeries Soluon • Accelearate ageing tests • Electrochemical Imped. Spectroscopy • Curve-fing • Thermal Impedance Spectroscopy

Accelerate Cycling Ageing RPT Accelerate Calendar Ageing (1 per week)

Rdc EIS η C

Equivalent Electrical Circuit

Publicaon: “Impedance-based model for LiFePO4 baeries in grid support applicaons,” in Advanced Baery Development for Automove and Ulity Applicaons and their Electric Power Grid Integraon. Münster, Germany on March 6-7, 2012. (accepted for presentaon in the poster session)

December 11, 2012 21

1.8. Post - Doc. Projects

In this project the following postdoc positions have been used:

- PostDoc in Power System – Assoc prof Ravindra Mukharjee (from July 2009 to May 2010)

- PostDoc in Energy Storage – Assoc Prof Claus Rasmunssen (from Sep 2008 – March 2010)

The main goal of these postdocs was to support the PhDs in affiliated topics.

1.8. Post - Doc. Projects 1.8. Post - Doc. Projects In this project the following postdoc positions have been used: 1.9. Lab setups In this project the following postdoc positions have been used: - PostDoc in Power System – Assoc prof Ravindra Mukharjee (fromThe July following 2009 tosetups May have been build (for more details please see Appendix 2) - 2010)PostDoc in Power System – Assoc prof Ravindra Mukharjee (from July 2009 to May MV lab for testing 6MW 3.3 kV converter (ca 2 mil DKK 2010) • - PostDoc in Energy Storage – Assoc Prof Claus Rasmunssen (from Sep 2008 – March - 2010)PostDoc in Energy Storage – Assoc Prof Claus Rasmunssen (from Sep 2008 – March 2010) The main goal of these postdocs was to support the PhDs in affiliated topics. The main goal of these postdocs was to support the PhDs in affiliated topics.

1.8. Post - Doc. Projects 1.8. Post - Doc. Projects 1.9. Lab setups 1.9. InLab this project setups the following postdoc positions have been used: The following setups haveIn this been project build the (for following more details postdoc please positions see Appendix have been 2) used: - PostDoc in Power System – Assoc prof Ravindra Mukharjee (from July 2009 to May The following setups have been build (for more details please see Appendix 2) 2010) - PostDoc in Power System – Assoc prof Ravindra Mukharjee (from July 2009 to May • MV lab for testing 6MW 3.3 kV converter (ca 2 mil DKK Research output – State-of-the Art facilies 2010) • Multi-level grid converter grid including grid simulator lab - ca 1 mil DKK • MV- labPostDoc for testing in Energy 6MW 3.3Storage kV converter – Assoc (caProf 2 Clausmil DKK Rasmunssen (from Sep 2008 – March

2010) - PostDoc in Energy Storage – Assoc Prof Claus Rasmunssen (from Sep 2008 – March 2010) The main goal of these postdocs was to support the PhDs in affiliated topics. The main goal of these postdocs was to support the PhDs in affiliated topics.

1.9. Lab setups 1.9. Lab setups

The following setups have been build (for more details please see Appendix 2) The following setups have been build (for more details please see Appendix 2) • MV lab for testing 6MW 3.3 kV converter (ca 2 mil DKK • RTDS system with 20 cores - ca. 2.5 mill (co funding from third party) • Multi-level grid conver terMV grid lab including for testing grid 6MW simulator 3.3 kV lab converter - ca 1 mil (ca •DKK 2 milBattery DKK tester with 2 ch, including EIS – ca. 1 mill DKK • • Multi-level grid conver ter grid including grid simulator lab - ca 1 mil DKK

• RTDS system with 20 cores - ca. 2.5 mill (co funding from third party) "*

• Multi-level grid converter grid including grid simulator lab - ca 1 mil• DKKRTDS system with 20 cores - ca. 2.5 mill (co funding from third party)

• Battery tester with 2 ch, including EIS – ca. 1 mill DKK • Multi-level grid converter grid including grid simulator lab - ca 1 mil DKK Battery tester with 2 ch, including EIS – ca. 1 mill DKK • "* Slide 22 December 11, 2012 "*

• Battery tester with 2 ch, including EIS – ca. 1 mill DKK

• Battery tester with 2 ch, including EIS – ca. 1 mill DKK "*

"*

"!"!

"! Research output

- 60+ Publicaons and 5 patent applicaons, Annual Symposium since 2008 December 11, 2012 Slide 23 • Power Electronics for Wind Power • Grid Supports with Wind Power Plant • Storage System for Grid Support • Grid Integraon of PV

December 10, 2012 24 Control of Grid Interacve PV Inverters for High Penetraon on LV Distribuon Networks Reactive power vs DG location Reactive power vs Voltage 0 0 Problem adaptive adaptive standard standard -20 -20 DG1 Limited PV penetraon level on LV networks ) )

% % ( (

n -40 n -40 P P • / / voltage

Voltage rise Q Q limit • Transformer overloading -60 -60

-80 -80 1 2 3 4 5 6 7 8 9 10 11 1.04 1.06 1.08 1.1 1.12 Soluon DG no voltage (p.u.) Reactive power vs DG location Reactive power vs Voltage New ancillary services by PV inverters 0 0 adaptive adaptive standard standard • Real power curtailment -20 -20 DG1 ) )

• Reacve power support (adapve Q(U)) % % ( (

n -40 n -40 P P / / voltage Q Q limit Transformer -60 -60 R, L R, L R, L R1, L1 R, L R1, L1 R, L

Grid Dyn5, 1:1 -80 -80 0.4 kV Rp,Rs 1 2 3 4 5 6 7 8 9 10 11 1.04 1.06 1.08 1.1 1.12 R ,L g g Lp,Ls DG no voltage (p.u.) PV1 PV2 PV3 PV4 PV7 PV8 PV11

Demirok, E., Gonzalez, P., Frederiksen, K.H.B., Sera, D., Rodriguez, P., Teodorescu, R., “Local reacve power control methods for overvoltage prevenon of distributed solar inverters in low voltage grids,” IEEE Journal of Photovoltaics, vol. 1, issue. 2, p. 174-182, 2011.

December 10, 2012 25 Diagnosc and Condion Monitoring in PV Power Systems Problem

• Large PV plants ulity scale Smart PV Distributed agents Inverter • Diagnosc and condion Localized Satellite Hotspot IV curves sensors irradiation Imaging monitoring funcons (G,T) maps

• Reliability and lifeme models IEC 61850 PV system Lifetime Yield Other Soluon models models analysis agents Smart PV • Intelligent modelling and Inverter

diagnosc systems based on Intelligent diagnostic and monitoring machine learning IEC 61850 system • IV, dark IV characteriscs

• Impedance spectroscopy Control and monitoring station · Intelligent maintenance • SWIR imaging · Lifetime maximization · Yield improvement • Accelerated solar cell ageing · Other diagnostic and IIEECC 6611885500 monitoring functions • Carrier lifeme • Diffusion length Electrical impedance spectrocsopy SWIR imaging Accelerated ageing and stress testing

Cracks/ Gain/Phase impedane Carrier Electroluminesence defects µ-PCD spectrum lifetime Resistance regions Sheet Equivalent dynamic SHR resistance Impedance models Photoluminesence Shunts analyzer SWIR camera Quantum WT 2000 LBIC Electric efficiency charcterization Carrier lifetime

Publicaon: ”Sensorless Diagnoscs for Residenal PV Systems”; S. Dezso, S. Spataru, M. Laszlo, T. Kerekes, R. Teodorescu In: 26th European Photovoltaic Solar Energy Conference and Exhibion (EUPVSEC 2011). Hamburg, Germany : ETA-Renewable Energies and WIP-Renewable Energies, 2011. p. 3776-3782.

December 10, 2012 26 Grid Support and Condion Monitoring for PV Systems Problem • Increased PV penetraon causes grid stability concerns (Ex.“50.2 Hz problem”) • Decrease of convenonal generaon require PVPPs to perform VPP acons • Need for PVPPs to offer reliable services on ancillary power markets • Aracve feed-in tariffs led to profitable businesses Soluon • Development of frequency stabilizaon funcons using coordinated control and communicaon • Create funcons for PVPP and compliance with future grid codes • Parcipaon of PVPP on the ancillary power markets and prove the economical benefits Overview of Recent Grid Codes for PV Power Integraon – Bogdan Craciun, Remus Teodorescu, 13th Internaonal Conference on OPTIMIZATION OF ELECTRICAL AND ELECTRONIC EQUIPMENT (Opm 2012). Brasov, Romania

December 10, 2012 27