Counter-rotating electric generator for wind power plants with liquid metal energy transfer

Abstract

The problem of creating effective structures that ensure mutual rotation of the rotor and stator of an electric generator. The wide practical application of counter-rotor wind-electric generators, which provide a significant increase in specific power, is hindered by the disadvantages and low reliability of existing systems for removing electric energy from the windings of a rotating counter-rotor, due to the dry friction mode. It is possible to increase the reliability of the contact removal of electrical energy from the counter rotor (rotating stator) by replacing solid brushes with liquid metal contact groups, which will lead to a certain increase in the resistivity of the contact group, compensated by the contact area of the liquid metal with the contact ring. It is most advisable to use liquid metal contact groups based on gallium, which will raise the permissible temperature limit of operation by about 2 times compared to the achieved level to 275 °C and, thereby, additionally raise the specific power of the electric generator.