Patent ID: 7821157

Claim:
A device for injecting reactive current onto an MV network ( 14 ) to which one or various electrical power generation machines are connected when a voltage dip occurs on said network ( 14 ) due to a mono-phase, two-phase, or three-phase fault, comprising: a) a medium voltage switch ( 1 ) on the connection of an output from a wind farm 16 to the network ( 14 ); b) an LV/MV transformer ( 2 ) on each phase; c) a dc/ac inverter ( 3 ) on each phase with IGBT or IGCT semiconductors; d) a dc capacitor ( 4 ) on each phase; and e) a control circuit ( 20 ) on each phase, connected to the controls ( 10 , 12 , 13 ) associated with each of the aforementioned units and which includes voltage and current sensors, a voltage dip detection circuit ( 10 ) with DSP, devices for calculating the instantaneous voltage on the network ( 14 ), and voltage comparison circuits, so that when the circuit ( 10 ) detects a voltage dip, reactive current from the output of the wind farm ( 16 ) is injected onto the MV network ( 14 ) in a variable manner at each time interval or cycle, based on the measurements provided by the sensors and circuits, taking the necessary active current from the network ( 14 ) to the capacitor ( 4 ).