Hybrid full bridge-half bridge MML power converter for HVDC diode rectifier connection of large off-shore wind farms

Because mostly used variable speed wind turbines based on doubly fed induction generator (DFIG) do not provide with transient voltage support capability under fault conditions, the security and stability of grid is influenced by wind farms integration in the case of severe short circuit fault contingency occurred on the grid side. The modified power converter controller model with transient voltage support capability and pitch control model used for post-fault stability control are implemented in DIgSILENT/PowerFactory. The models validation and the contribution to transient voltage stability enhancement are verified by power system simulation containing large wind farms. From simulation results, it can be illustrated that modified power converter controller with transient voltage support capability can provide dynamic reactive power to support grid voltage recovery and the modified pitch control model can reduce mechanical power , preventing wind turbines from over-speeding and also providing more reactive power generation stability for the power converter controller in the duration of power system large disturbance. The conclusion is presented that the control strategy can effectively improve the transient voltage stability of the gird.

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An Investigation of the Low Voltage Ride through Function of GE DFIG Wind Turbines for Electro-Mechanical Simulations

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.608-609.537 ◽

2012 ◽

Vol 608-609 ◽

pp. 537-542

Author(s):

Zhao Jun Meng

Keyword(s):

Wind Turbine ◽

Large Scale ◽

Low Voltage ◽

Short Circuit ◽

Wind Farms ◽

Power Converter ◽

System Stability ◽

Total System ◽

Detailed Model ◽

Low Voltage Ride Through

Doubly-fed induction generator (DFIG) wind turbine has become the most widely used wind turbine in wind farms, since it presents noticeably advantages such as decoupled controls of active and reactive powers, and the use of a power converter with a rated power of 25% of total system power. As the penetration of wind power in power system increases, it is required that the wind turbine remained connected and actively contributed to the system stability during and after faults and disturbance. One common approach for a DFIG to obtain such low voltage ride through (LVRT) function is to install a crowbar circuit across its rotor terminals, which short circuit the rotor side converter when over-current is detected in the rotor. A detailed model of LVRT function normally requires electromagnetic simulations. However, the time consuming computational process is prohibitive for the studies of the integration of wind farms into large scale power systems. Electromechanical simulations are more suitable for such engineering applications. GE has incorporated the LVRT function into its recently released DFIG wind turbine model for Electro-mechanical simulations. This paper has implemented this model and verified the effectiveness of the LVRT function.

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Permanent magnet synchronous generator offshore wind farms connected to a single power converter

IEEE PES General Meeting ◽

10.1109/pes.2010.5588209 ◽

2010 ◽

Cited By ~ 7

Author(s):

Oriol Gomis-Bellmunt ◽

Adria Junyent-Ferre ◽

Andreas Sumper ◽

Joan Bergas-Jane

Keyword(s):

Permanent Magnet ◽

Wind Farms ◽

Synchronous Generator ◽

Power Converter ◽

Offshore Wind ◽

Permanent Magnet Synchronous Generator ◽

Offshore Wind Farms ◽

Single Power

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Design and Optimization of Scour Protection for Offshore Wind Platform DolWin Beta

Volume 9A: Ocean Renewable Energy ◽

10.1115/omae2014-23154 ◽

2014 ◽

Author(s):

Ben de Sonneville ◽

Greta van Velzen ◽

Jan Wigaard

Keyword(s):

Shear Failure ◽

Wind Farms ◽

Power Converter ◽

Offshore Wind ◽

Long Term Effects ◽

Offshore Wind Farms ◽

Design And Optimization ◽

German Coast ◽

Set Up ◽

Scour Protection

DolWin Beta is a large offshore power converter platform, which will be used to connect multiple offshore wind farms off the German coast to the main land. It will be located in a water depth of 29m, where tidal currents and harsh wave conditions may cause soil erosion (scour) and possibly undermining of the foundation if not protected properly. Laboratory experiments were conducted in order to investigate the scouring around the foundation and provide an optimized layout for scour protection. This paper summarizes the initial scour assessment, the design approach for scour protection, the experimental set-up, test program, monitoring techniques and results of the experiments. The test results revealed which zones of the scour protection around the foundation were most sensitive to shear failure and edge scour. In steps, the scour protection was strengthened in these zones and reduced in the more sheltered areas. The tests showed that the magnitude of rock displacement, apart from wave height and direction, was significantly influenced by the superimposed current velocity. Based on a test without scour protection, the sequence of installation was adjusted to minimize risks of scour during installation. Finally, a stable scour protection layout was obtained that was fully verified under extreme storms and long-term effects of edge scour.

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Comparative Study of Different Grid Connected Wind Energy Conversion System Configurations

Journal of Informatics Electrical and Electronics Engineering (JIEEE) ◽

10.54060/jieee/002.02.024 ◽

2021 ◽

Vol 2 (2) ◽

pp. 1-13

Author(s):

Virendra Kumar Maurya ◽

Keyword(s):

Renewable Energy ◽

Wind Energy ◽

Comparative Study ◽

Energy Conversion ◽

Reactive Power ◽

Wind Farms ◽

Power Converter ◽

Technical Parameters ◽

World Energy ◽

Energy Conversion Systems

As per the present scenario of the world energy crisis, Renewable energy conversion systems (wind energy) have become the most prominent alternative in the field of renewable energy, especially at offshore locations due to the availability of wind in huge amounts round the clock. This paper summarizes the comparative study of most commonly used generators and power converters configurations at off-shore/on-shore wind farms. A comparison study has been done on the basis of their fixed/variable speed operation, MPPT ability, FRT ability, power converter utilization, power factor, reactive power compensation, with and without gearbox, and other technical parameters.

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