Vensys 62 The next Generation of Gearless Wind Turbines goes into Production F. Klinger, INNOWIND GmbH J. Rinck, Vensys GmbH S. Balzert, FG Windenergie S. Jöckel, INNOWIND GmbH S. Jöckel: Vensys 62 Next Generation of Gearless Wind Turbines 1 / 14
Overview Vensys 62 1 Rotor blade 2 Cast hub 3 Pitch drive 4 Generator rotor 5 Generator stator 1 5 7 10 6 Azimuth drive 7 Anemometer 3 2 8 6 8 Main frame 9 Tower 4 10 Auxiliary crane 9 S. Jöckel: Vensys 62 Next Generation of Gearless Wind Turbines 2 / 14
Generator Design Stator Bearings Winding Permanent magnets Rotor yoke Iron core Rotor Axle Permanent magnet excitation High partial load efficiency Compact and low-weight design External rotor, internal stator Largest airgap diameter for given dimensions Cool magnets, high flux, no demagnetisation Passive cooling system Robust, no additional energy needed High cooling performance Integrated bearing concept No extra generator bearings needed S. Jöckel: Vensys 62 Next Generation of Gearless Wind Turbines 3 / 14
Patented Cooling Concept Iron core with backside cooling fins Permanent magnets Stator winding Generator rotor Cooling duct Generator stator S. Jöckel: Vensys 62 Next Generation of Gearless Wind Turbines 4 / 14
Frequency Converter PM Generator Step-up converter DC Link IGBT inverter Diode rectifier Braking chopper Diode rectifier: Cheap, reliable and efficient Small dv/dt in generator windings 3-phase transformer Grid 20 kv S. Jöckel: Vensys 62 Next Generation of Gearless Wind Turbines 5 / 14
Vensys 62 - Exterior View Ball-shaped nacelle casing: Least material for given volume Completely enclosed azimuth system Simply beautiful!! S. Jöckel: Vensys 62 Next Generation of Gearless Wind Turbines 6 / 14
Generator Test Rig 1.2 MW Generator Torque support generator Torque support Gearbox gearbox Auxiliary bearing S. Jöckel: Vensys 62 Next Generation of Gearless Wind Turbines 7 / 14
High-power Generator Test 5 Main Objectives of generator lab test: 1. Pre-commissioning of generator system (PM generator + frequency converter) 2. Test of interaction between PM generator and frequency converter and fine-tuning of torque control 3. Validation of calculated flux, voltage, current and efficiency characteristics 4. Preliminary measurements of generator noise emission 5. Proof of compliance with E.On requirements for grid compatibility S. Jöckel: Vensys 62 Next Generation of Gearless Wind Turbines 8 / 14
Test Results (1) Stator voltage and current at full load Generator voltage / current 1,5 1 0,5 0-0,5-1 -1,5 Voltage (standardised) Current (standardised) 0 10 20 30 40 50 60 70 80 90 100 Time in milliseconds Typical blockshaped stator voltage Current well smoothed by large inductances Both voltage and current characteristics like simulated before!! S. Jöckel: Vensys 62 Next Generation of Gearless Wind Turbines 9 / 14
Test Results (2) E.On requirements for grid compatibility (measured by DEWI) power output/rated power output idle power/rated Wirkleistung/Nennleistung power output (kvar/kw) Blindleistung/Nennleistung [kvar/kw] 0.5 0.4 0.3 0.2 0.1 0-0.1-0.2-0.3 Blindleistung Wirkleistung Drehmoment 03/03/20-11:22:01 8 8.2 8.4 8.6 8.8 9 9.2 9.4 9.6 9.8 10 Zeit time t [s] 200 175 150 125 100 75 50 25 0 Generatordrehmoment [knm] generator torque Measured torque Active power Reactive power Torque well controlled, converter delivers active and reactive power E.On requirements are met!! S. Jöckel: Vensys 62 Next Generation of Gearless Wind Turbines 10 / 14
Test Results (3) Efficiency (directly measured 1 - P out / P in ) 100 Converter (7 data points) Freq. converter and generator separately measured (accuracy!) Efficiency / % 90 80 70 60 50 Total efficiency (7 data points) Typ. generator + gearbox (calc.) Generator (760 data points) 0 200 400 600 800 1000 1200 Generator output power / kw Total efficiency η tot = η Con * η Gen Rated total efficiency over 94 %!!! Between 2.5 and 5 % higher efficiency than conventional drive train!!! S. Jöckel: Vensys 62 Next Generation of Gearless Wind Turbines 11 / 14
Main Technical Data 1. Rotor Rotor blades: Diameter: Control: Speed range: 3 x LM 29.1 P 62 m pitch 11-20 rpm 2. Direct Drive Generator Type: multipole synchronous Excitation: permanent magnets Rated power: 1200 kw 3. Safety system Full-span blade pitch, 3-times redundant 4. Tower head Mass less rotor: Rotor mass: 5. Tower Type: Hub height: Mass: ca. 56 t ca. 23 t conical steel tube 69 m 98 t 6. Wind Class: GL III, 8.5 m/s, 20 % TI S. Jöckel: Vensys 62 Next Generation of Gearless Wind Turbines 12 / 14
Prototype Erection Wind Turbine Site Sitzerath (Northern Saarland) Wind Conditions AWS: ca. 6.2 m/s (hub height) Turbulence: ca. 15 % (at 6.2 m/s) Measurements (ongoing) 1. Loads and safety system 2. Power curve 3. Noise emission 4. Grid compatibility Goal: Type Certificate in 2003 S. Jöckel: Vensys 62 Next Generation of Gearless Wind Turbines 13 / 14
Summary & Outlook Design, construction, erection, test of gearless Vensys 62, 1200 kw Direct drive, PM generator Reliable frequency converter Passive cooling High-power generator lab test High efficiency validated E.On compliance proven Low noise emission shown Prototype testing (ongoing) Loads and safety system Power curve, noise and grid Outlook Production of pilot series of 5 additional machines started Development of follow-up turbine in the 2-2.5 MW class started S. Jöckel: Vensys 62 Next Generation of Gearless Wind Turbines 14 / 14