Internal gear pump structure and other gear pump structure similar to, mainly by the outer rotor and rotor, pump shaft, pump body, the front cover, bracket, sealing device, bearing, etc.

Cycloidal tooth profile of the internal gear pump, also called cycloidal rotor pump, pump the small gear and internal gear only related a tooth, so the internal gear pump do not need to set partition.

The accuracy of the rotor speed estimation in speed sensorless vector control system of induction motor under load is sensitive to parameter errors of the internal machine model.