Research On Axial Flux Variable-reluctance Resolver With Sinusoidal Rotor

Resolver, as position and speed sensor is widely used in motor control system,because of the advantage of high precision, high temperature and humidityresistance and strong anti-interference ability. Especially variable-reluctanceresolver which has incomparable reliability plays a very important role in NationalDefense, space flight, Automobiles and so on. The existing variable reluctanceresolver usually use radial circuit structure, which has large volume. A new kind ofaxial flux variable reluctance resolver with sinusoidal rotor is put forward in thispaper with compact structure, high reliability and strong anti-interference ability. Asa result, it will be a new research direction of resolver in future.Firstly, the reluctance variation principle of radial and axial flux variablereluctance resolver is analyzed. By using calculus method, the formulation ofcoupling area changing along with rotor angle is got, and then the mathematicsmodel and electrical work principle are given.Electromagnetic property of the resolver is analyzed. By using3D timestepping FEM, output voltage in different pole-pair axial flux variable reluctanceresolver are analyzed. Through the Analysis and comparison of the HURnofharmonization of output voltage, the reason of high accuracy of multi pole resolveris analyzed.To eliminate the harmonization in output voltage, analytical and finite elementmethod is adopted to optimize the structure parameter, especially the tooth numberand the shape of rotor. Design principles of different pole pairs were achieved. Thisprovides a useful data evidence for the design of axial flux variable reluctanceresolve with sinusoidal rotor and therefore an important meaning in practicalengineering.Finally, the effects of stator and rotor eccentricity on precision are deeplyanalyzed. The cause of non-effect EMF and the compensating effect among the samephase coils was demonstrated by analytical method. The simulation results prove thecorrectness of the theory. The prototype of one pole-pair axial flux variablereluctance resolver was made and its performance in the situation of eccentricitywas tested.