文档介绍：Morten Lindholm
Doubly Fed Drives for Variable
Speed Wind Turbines
A 40kW laboratory setup
Technical University of Denmark
Ørsted
2800 Lyngby
Denmark
To Katrina, Oskar and Frederik
vii
Student: . Morten Lindholm
ID# : s928912
Company: NEG Micon Control Systems A/S
Frankrigsvej
8450 Hammel
Denmark
Tel: (+45) 87 62 26 00
University: Technical University of Denmark
Ø
Anker Engelundsvej
2800 Lyngby
Denmark
Financing: This project is fully funded by
NEG Micon Control Systems A/S.
Supervisor:
University main supevisor: Jørgen Kaas Pedersen
April 2000 - April 2002: Technical University of Denmark
Retired Ø
April 2000 - September 2003: Tonny W. Rasmussen
Technical University of Denmark
Ø
University secondary supervisor Kurt Andersen
April 2002 - September 2003: Technical University of Denmark
Ø
Industrial supervisor: Jan Kristiansen
NEG Micon Control Systems
Abstract
This thesis deals with the use of variable speed wind turbines. Different
wind turbine generator topologies are described. In particular, the reduced
variable speed turbine, which uses a doubly fed induction generator, is
covered.
An overview of the power electronic inverters of interest to the field of
wind energy is given and a topology for a laboratory model is selected.
The discipline of Pulse Width Modulation is presented.
The vector control principles of induction machines and grid connected
inverters are derived. Having the stator connected direct to the grid gives
that the flux level in the machine is nearly constant. This means that
changes of either the flux or torque producing current in the rotor circuit
is limited by the transient time constant of the machine.
A 40 kW laboratory model with a doubly fed induction generator and a
3-level neutral point clamped back to back power converter is constructed.
Adaptive active filters are used to reduce harmonics and slip harmonics
in the stator curre