Wind energy installation with an autonomous energy supply for a blade adjustment device

Abstract

Wind energy installation with a generator (13) which is driven by a rotor (2) with adjustable rotor blades (21), for producing electrical energy, wherein a pitch adjustment device (3) is provided for adjusting the blades, which pitch adjustment device comprises an emergency circuit (5) with an energy store (50) for actuating a blade actuating motor (55). The invention provides for a shunt branch (60) with a current-balancing device (6, 6′) to be provided in parallel with the energy store (50), wherein the current-balancing device (6, 6′) is designed so as to control the current shunt branch (60) depending on a feedback current from the blade actuating motor (55). The invention provides a current balancing circuit (6), with which the feedback current occurring in the overrunning state is dissipated in controlled fashion via a shunt branch and therefore the electrical energy store (50) is protected from a damaging feedback current. The invention therefore achieves a situation in which a damaging rise in the voltage of the electrical energy store (50) and a rise in the motor speed of the blade actuating motor (55) are prevented during overrunning operation. The invention relates to a corresponding method.

Dependencies are inferred from the claim text.