What is the difference between fixed and variable speed wind turbines?
Fixed speed wind turbines can deliver their rated power only at a very limited range equal to ± 1% of rated wind speed. So that any change in wind speed will cause a fluctuation in its output power. Variable speed wind turbines can operate at a wide range of wind speeds with maximum power conversion efficiency.
What is variable speed generator?
A variable speed generator (Dynawatt, DometicTravel_power) produces a precise 230VAc electrical voltage directly from a boat or vehicle engine, independently of engine speed. One problem is that the power output depends on speed of the engine.
Which generator is used in fixed speed wind turbine?
Out of these two types of wind turbines, the most commonly used is the fixed-speed turbine, where the induction generator is directly connected to the grid.
What are the advantages and disadvantages of fixed speed turbines?
The fixed-speed wind turbine has the advantage of being simple, robust and reliable and well-proven. And the cost of its electrical parts is low. Its disadvantages are an uncontrollable reactive power consumption, mechanical stress and limited power quality control.
Do wind turbines have variable pitch?
Variable pitch control can be used to shed the aerodynamic power generated by the wind turbine. Thus, the aerodynamic power produced by the wind turbine can be controlled by adjusting the pitch angle of the wind turbine.
Which generator is used in variable speed wind energy conversion system?
Which generator is used in variable speed WECS? Explanation: Double-fed induction generator is used in a variable speed WECS.
What is fixed speed wind turbine?
A fixed-speed wind turbine always spins at the same generator/rotor speed during operation, regardless of the wind speed. Thus, the tip-speed ratio (TSR) would change with wind speed and the rotor aerodynamic performance would only be optimal at a given wind speed.
What are the different types of generators used in wind turbine?
Traditionally, there are three main types of wind turbine generators (WTGs) which can be considered for the various wind turbine systems, these being direct current (DC), alternating current (AC) synchronous and AC asynchronous generators. In principle, each can be run at fixed or variable speed.
How does variable speed wind turbine work?
A variable-speed wind turbine allows the generator/rotor speed to vary proportional to wind speed between cut-in and rated speed, thus maintaining a constant TSR and optimal aerodynamic performance. Above rated speed, the generator/rotor speed is then held constant. The torque must be actively controlled.
Which generator is used in variable speed WECS?
Which generator is used in variable speed WECS? Explanation: Double-fed induction generator is used in a variable speed WECS. The name doubly-fed comes from the fact that the stator voltage is applied from the grid and the rotor voltage is impressed by the power converter.