300 likes | 526 Views
Simulation platform for Wind Turbines by Professor Frede Blaabjerg Aalborg University fbl@iet.auc.dk http://www.iet.auc.dk/~fbl/ November 28, 2003. Outline. Background Wind turbine concepts Basic model library Simulation examples Conclusion. 1. Background. Why.
E N D
Simulation platform for Wind Turbines by Professor Frede Blaabjerg Aalborg University fbl@iet.auc.dk http://www.iet.auc.dk/~fbl/ November 28, 2003
Outline • Background • Wind turbine concepts • Basic model library • Simulation examples • Conclusion
1. Background Why • Electrical system of the wind turbine in steady progress and become more and more important • Wind turbines grow in size (3-5 MW) • Virtual prototyping is the only method for analysis and evaluation Goals • Develop an extended simulation platform for electrical parts in wind turbines • Develop models which may used in mechanical / aeroelastical design tools like HAWC
1. Background Modelling aspects
2. Wind Turbine Concepts • Active stall/stall wind turbine • Fixed Speed • Squirrel-Cage Induction Generator • Soft-starter, Capacitor Bank • Pitch control wind turbine • Variable Speed • Squirrel-Cage Induction Generator • Back-to-Back Power Converter
2. Wind Turbine Concepts • Pitch control wind turbine • Variable Speed • Double-Fed Induction Generator • Back-to-Back Power Converter • Pitch control wind turbine • Variable Speed • Multi-Pole Synchronous Generator – direct driven • Rectifier + Inverter
3. Basic model library Structure of Wind Turbine Blockset in Matlab/Simulink
3. Basic model library • Squirrel-cage IG • Doubly-fed IG • Synchronous Machine • PMSM • Dynamic models • dq/dq models • abc/abc models • Reduced order models • Steady-state models • Optimized for speed (C S-Function version)
3. Basic model library Simulation speed important
3. Basic model library • wind model – take into account the rotational turbulences and the tower shadow • wind turbine rotor – based on torque coefficient look-up tablel • different drive-train models • one-mass model • two-mass model
3. Basic model library • switching models • average models • rectifiers • voltage source converters • soft-starter • star • delta • branch-delta • modulation strategies
3. Basic model library • abc/abc model for 3-phase 2-winding transformer • take into account iron losses and core geometry
4. Simulation examples Simulink example
4. Simulation examples Simulink simulation results
HAWC kernel Active stall wind turbine with asynchronous generator Gear Interface variables to the grid: voltage current Pitch control wind turbine with doubly fed generator Gear 4. Simulation examples Implementation boundaries HAWC dll • 1. Generator model (directly in HAWC) • - SCIG • - DFIG • 2. Power converter control (dll subroutine) • - frequency converter • - softstarter • 3. Wind turbine control (dll subroutine) Soft-starter Power converter HAWC
4. Simulation examples HAWC: Active stall control 6 m/s Green: Old Model Red: New model 6 m/s
I Rotor side converter control rotor Power control loop Speed control loop 4. Simulation examples Digsilent: Variable speed/ variable pitch wind turbine Measurement grid point M N DC AC AC DC T PWM PWM Network side converter control DFIG control Wind turbine control
rated rated P P mec mec w nom AB: gen BC: CD: 4. Simulation examples Digsilent: Control strategies Power curve w w Power curve P P - - curve curve 2500 2500 2500 2500 Power limitation Power limitation Dynamic speed range Dynamic speed range Power optimisation Power optimisation ref. ref. C, D C, D 2000 2200 2000 2000 C C D D var. ref. var. ref. fixed fixed speed speed [kW] speed speed ower 1500 1500 1500 1500 Mechanical power [kW] Electrical power [kW] p Mechanical 1000 1000 1000 1000 B B B B 500 500 500 500 nom n rated rated u u gen A A A A 0 0 0 0 0 0 200 200 400 400 600 600 800 800 1000 1000 1200 1200 1400 1400 1600 1600 1800 1800 2000 2000 0 0 5 5 10 10 15 15 20 20 25 25 W W ind ind speed speed [m/s] [m/s] Generator speed Generator speed [rpm] [rpm]
4. Simulation examples Digsilent: Power limitation with gain schedulling (wind 22 m/s)
4. Simulation examples SABER: Saber diagram of a directly grid-connected squirrel-cage induction generator
5. Conclusion • Wind Turbine Toolbox (Matlab/Simulink) • Improved models HAWC (IG, DFIG) • DIgSILENT Power Factory (Now a toolbox) • Toolbox for SABER (A toolbox) • Validated models (Wind turbine and wind farms) • Simulations have shown new behaviours
5. Conclusion Virtual Electrical Prototyping of Wind Turbines Focus on • New models for new configurations • Improved models (Special cases, grid, generator, • power electronics) • Advanced control of turbine • Optimization of wind turbines • Models in use (Wind turbine manufacturer specific)