Electrical drive unit for use in wind power machine i.e. windmill, to adjust rotor blades, has commutator provided for successively connecting supply terminals with potentials, where supply terminals are provided in three-phase motor

摘要

The unit (1) has a three-phase motor (2) adjusting angle of incidence of rotor blades of a windmill, an alternating current (AC) source (5), a direct current (DC) source (6) and a mechanical commutator (10). The motor has supply terminals (UM, VM, WM) that are controlled by the AC source in a normal operation and controlled by the commutator in a standby operation, where the commutator is supplied with current from the DC source. The DC source has taps (60-63) providing potentials that are different from each other. The commutator successively connects the terminals with the potentials.