1. ANALYSIS AND TESTING OF SMALL WIND TURBINES CONNECTED TO WEAK AND AUTONOMOUS GRIDS
LUIS CANO
LUIS M. ARRIBAS
CIEMAT (Spain)

2. SWT connected to the grid:
INDEX
Background
SWT connected to the grid:
State of the art
SWT
Inverters - Measurements
Standards revision
SWT connected to Autonomous systems.
DC-coupled
Case study: CICLOPS system.
AC-coupled
Case study: HYBRIX system.
EWEC 2006, Athens

3. BACKGROUNDS 100 m Mast SWT Measuring General view: phase I
EWEC 2006, Athens

4. BACKGROUNDS SWT Measuring Meteorological Masts General view: phase II
EWEC 2006, Athens

5. CIEMAT’s TEST FACILITY: Power Performance Tests. (IEC 61400-12)
BACKGROUNDS
CIEMAT’s TEST FACILITY:
Power Performance Tests. (IEC )
Noise Emission Measurement (IEC )
Safety and Function Tests (IEC WT 01)
Measurements of grid connected SWT (IEC )
Duration Tests (IEC WT 01)
Other Test
Generators performance
Blade Test
EWEC 2006, Athens

6. SWT connected to the grids: State of the art
CONNECTION TOPOLOGIES: 1
RECTIFIER CHOPPER INVERTER
(Optional)
GRID 2
GRID
EWEC 2006, Athens

7. SWT connected to the grids: State of the art
Principal SWT connected to grids in Europe (I)
Source: Manufacturer webpages
EWEC 2006, Athens

8. SWT connected to the grids: State of the art
Principal SWT connected to grids in Europe (II)
Source: Manufacturer webpages
EWEC 2006, Athens

9. SWT connected to the grids: State of the art
Inverters
6 THYRISTOR BRIDGE INVERTER R S T DC
EWEC 2006, Athens

10. SWT connected to the grids: State of the art
Inverters
6 IGBT PWM INVERTER R DC S T
EWEC 2006, Athens

11. SWT connected to the grids: State of the art
Inverters. Case: 6 IGBT PWM INVERTER
EWEC 2006, Athens

12. Measurements of grid connected SWT
Data of SWT measured. Case of a 5kW 6 IGBT PWM inverter
EWEC 2006, Athens

13. Standards revision. IEC 61000 standards on EMC:
3-2: “Limits for harmonic current emissions (equipment input current up to and including 16 A per phase).”
3-3: “Limitation of voltage fluctuation and flicker in low-voltage supply systems for equipment with rated current of 16 A.”
4-7: “Harmonics and Interharmonics Measurements and Instrumentation for Power Supply Systems”
4-11: “Voltage Dips, Short Interruptions, and Voltage Variations Immunity Test”
4-15: “Flickermeter”
6-3 Ed 2 (RDIS): “Generic standards -Emission standard for residential commercial and light industrial environments”
6-4: “Generic standards -Emission standard for industrial environments”
EWEC 2006, Athens

14. Standards revision. Other local Standards. American Standards:
UL Static Inverters and Charge Controllers
IEEE 519 Harmonic Control in Electric Power Systems
IEEE 929 Utility interface of Photovoltaic
ANSI C62.41, C1, C2 Surge Voltages in Low-Voltage AC Power Circuits
British Connection Standards
GE 59, 83 Embedded Generating Plants, Small-scale generators (up to 16A)
GE 77 Single-phase photovoltaic generators up to 5kVA
German Standards
VDE 0126 Automatic Disconnection Facility for PV Installations
Others
KEMA K150 Small Grid-connected Photovoltaic Systems
JIS C 8962 Power Conditioners for Small PV Power Generating Systems
ÖNORM/ÖVE 2750 Austrian Guideline - PV Power Generation Systems
NEN1010 Grid-connected PV Systems
AS3000, AS4777 Australian - Connection of Energy Systems
CSA F381 Canadian - Power Conditioning Systems
EWEC 2006, Athens

15. ~ SWT connected to Autonomous systems.
Connection Topologies (I): DC-Coupled
Energy Use + -
Rectifier
Regulator
Wind
Turbine
Battery
Storage
Back-up
Genset ~
Stand-alone
Inverter
DC Side
AC Side
EWEC 2006, Athens

16. SWT connected to Autonomous systems.
Connection Topologies (I): DC-Coupled
Power electronics
Rectifier (for the SWT)
DC/DC converter (optional)
Stand-alone Inverter
self-commutated
voltage controlled
Stabilizing Unit
long-term storage (battery)
“One-way” converter (inverter)
Traditional and common way of connection
Well known (stand-alone systems)
High quality, relative low price
PQ dependant on:
the inverter
the load
not on the SWT
Wind
Turbine
Battery
Storage
Back-up
Genset - +
DC Side
Rectifier +
Regulator ~
Stand-alone
Inverter
AC Side
Energy Use
Energy Use
Energy Use
Energy Use
EWEC 2006, Athens

17. Case Study: CICLOPS Project Description
DC-Coupled SWT connected to Autonomous systems.
Case Study: CICLOPS Project Description
7.5 kW SWT
5 kWp PV array
20 kVA Genset
595 C10 Battery Storage
EWEC 2006, Athens

18. Case Study: CICLOPS Project – Data Logging Description
DC-Coupled SWT connected to Autonomous systems.
Case Study: CICLOPS Project – Data Logging Description
EWEC 2006, Athens

19. Case Study: CICLOPS Project – WT Power Curve
DC-Coupled SWT connected to Autonomous systems.
Case Study: CICLOPS Project – WT Power Curve
EWEC 2006, Athens

20. DC-Coupled SWT connected to Autonomous systems.
Case Study: CICLOPS Project – Inverter characterization
Wave form (3400 W resistive load)
Harmonic Distortion for orders from 2 to 50 (3400 W resistive load)
EWEC 2006, Athens

21. Case Study: CICLOPS Project – Inverter characterization
DC-Coupled SWT connected to Autonomous systems.
Case Study: CICLOPS Project – Inverter characterization
Harmonic Distortion for 1 phase (U, I, P) for different resistive loads (cos Φ = 1).
EWEC 2006, Athens

22. ~ ~ SWT connected to Autonomous systems.
Connection Topologies (II): AC-Coupled
Wind
Turbine
Back-up
Genset
Battery
Storage + - ~ ~
Grid-connected
Inverter
Bi-directional
Converter
AC Side
Energy Use
Energy Use
Energy Use
Energy Use
EWEC 2006, Athens

23. SWT connected to Autonomous systems.
Connection Topologies (II): AC-Coupled
Power electronics
Rectifier
DC/DC converter (optional)
Inverter (optional)
Bi-directional converter
Stabilizing Unit
long-term storage (battery)
Recently developed
AREP Project
SMA concept technology
PQ dependant on:
AC coupled devices (including the SWT)
the inverter
the load
Wind
Turbine
Back-up
Genset
Battery
Storage + -
Grid-connected
Inverter ~ ~ ~
Bi-directional
Converter
AC Side
Energy Use
Energy Use
Energy Use
Energy Use
EWEC 2006, Athens

24. Case Study: HYBRIX Project Description
SWT connected to Autonomous systems.
Case Study: HYBRIX Project Description
10 kW Vergnet SWT;
30.8 kW PV array and
20 kVA diesel genset.
3 lead acid batteries
(2x2200 Ah, 1x800 Ah, 60 volts)
Sunny Island Inverters
From “Iberinco desarrolla el sistema híbrido de generación eléctrica aislado Hybrix ”. Infoenergía.com
EWEC 2006, Athens

25. Case Study: HYBRIX Project PQ issues - Sunny Island characteristics
SWT connected to Autonomous systems.
Case Study: HYBRIX Project PQ issues - Sunny Island characteristics
EMC interference
Harmonic Distortion
EWEC 2006, Athens

26. CONCLUSIONS Each country has its own Grid-connection standards
Lack of optimal coupling between the converter and the turbine. (Most of manufacturers buy the inverter and don´t adapted it)
Except few ones, it´s not easy to know if the inverters fulfilled the standards
Inverters are carried out for PV market
Technology is not mature
Certification in each country is very costly
EWEC 2006, Athens

27. THANK YOU FOR YOUR ATTENTION!
EWEC 2006, Athens