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

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

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

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

CIEMAT’s TEST FACILITY: Power Performance Tests. (IEC 61400-12) BACKGROUNDS CIEMAT’s TEST FACILITY: Power Performance Tests. (IEC 61400-12) Noise Emission Measurement (IEC 61400-11) Safety and Function Tests (IEC WT 01) Measurements of grid connected SWT (IEC 61400-21) Duration Tests (IEC WT 01) Other Test Generators performance Blade Test EWEC 2006, Athens

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

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

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

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

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

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

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

Standards revision. IEC 61000 standards on EMC: 3-2: 2001. “Limits for harmonic current emissions (equipment input current up to and including 16 A per phase).” 3-3: 1997. “Limitation of voltage fluctuation and flicker in low-voltage supply systems for equipment with rated current of 16 A.” 4-7: 2004. “Harmonics and Interharmonics Measurements and Instrumentation for Power Supply Systems” 4-11: 2004. “Voltage Dips, Short Interruptions, and Voltage Variations Immunity Test” 4-15: 2004. “Flickermeter” 6-3 Ed 2 (RDIS): 2004. “Generic standards -Emission standard for residential commercial and light industrial environments” 6-4: 2002. “Generic standards -Emission standard for industrial environments” EWEC 2006, Athens

Standards revision. Other local Standards. American Standards: UL 1741 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

~ 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

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

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

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

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

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

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

~ ~ 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

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

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

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

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

THANK YOU FOR YOUR ATTENTION! EWEC 2006, Athens