With domestic wind power technology matures, wind turbines gradually from the small, landlocked fans began to large-scale, direct drive, offshore wind power development. The direct drive wind turbine technology particularly rapid development, especially in the large fans, direct-drive technology has special advantages. For direct drive generator in operation in order to accurately measure and control the rotor speed, rotor speed measuring device is required. In particular, for security reasons, you need at least two speed measuring device. The usual practice is on the generator internal friction disc cut-out speed, disadvantage of such speed device is not easy to repair, replace. Another common approach is coaxial and electric generator attached to one end of the slip ring encoder speed measurement, this gun is safe and reliable manner, but higher cost.

Cosmau for the above-mentioned technical problems, provide a relatively low cost, the replacement of the maintenance simpler direct drive motor rotor slip rings. A technical solution to achieve the following direct-drive motor rotor slip ring, comprising a signal plate, slip ring, proximity switches and holder, slip ring fixed to the stationary part of the motor stator and rotating parts connected to the slip ring and rotor the impeller hub connections, rotating parts signal plate and slip ring connections, the proximity switch through its fixation on a stationary part of the slip ring, stationary components and motor stator slip ring connections, proximity switch signal line connect with external control system. The signal plate uniformly along its disc with a plurality of holes, said holes corresponding to the position of the proximity switch. Open some holes on the signal plate round hole, square hole, oval hole, the long hole, diamond hole or scallops. Slip ring rotating parts of the utility model, the slip ring by connecting the wind turbine hub, and set the slip ring is rotated signal disk unit, for signal disc and hub synchronous rotation, by the proximity switch detects the pulse signals and transmitted to the external control system, realization detected motor rotor speed. Its structure is simple, low cost, bare outside the motor housing for easy replacement and maintenance.