The problem

Some wind turbine technologies connected to electricity networks respond to voltage sags or interruptions in

the network by shutting down automatically in the case of a drop in voltage.

When the increase in the wind power generated in an area exceeds a value with regard to the power from

other forms of generation, these wind turbines are required to continue generating during voltage sags,

following the time/depth pattern represented in the following figure for values established by the electricity

company in each case.

Typical behaviour of the network during short-circuits

Admissible voltage-time curve at the network connection point

Operation of the EOLIC SEPEC

The EOLIC SEPEC is interconnected between the generator and the

network. In normal network regime it behaves like a closed switch.

During the failure, it behaves as follows:

1- With regard to the wind turbine, voltage is supplied as if it

came from the network and the wind turbine is kept in normal

operation.

2- With regard to the network, an active and reactive pattern is

generated in accordance with the needs of the network.

3- During the failure, excess power is dissipated internally by

EOLIC SEPEC

Optionally, SET Q can be equipped to adapt reactive power both during

the gap and in permanent regime.

Table comparing sags adaptation systems

*Spanish standard