Research On Switched Reluctance Motor With Asymmetric Rotor Structure And Torque Ripple Suppression Technology

Two phase switched reluctance motor is a class of motor with less number of phases, it is reducing the number of phases that makes the motor structure is more simple and cost is more affordable, and it is very suitable for high speed and household application. Although the two phase switched reluctance motor have many advantages,but there are also have some problems, such as special location can not be self-starting,large torque ripple, outstanding noise and vibration. This paper proposes a new two phase switched reluctance motor with asymmetric rotor structure, the motor can not only solve the problem of self-starting, while effective in suppressing the torque ripple and reduce system noise. The paper researchs on mechanism analysis, structural parameter optimization and torque ripple suppression technology, the main research work is as follows:First, through analyses the basic structure and working mechanism of switched reluctance motor with asymmetric rotor structure, and to explore asymmetric rotor structure to achieve the mechanism of self-starting and the impact on the motor magnetic circuit, flux and inductance. In-depth stduy on rapid non-linear model based on magnetization curve with special position, and the paper proposes improved simplify magnetization model suitable for switched reluctance motor with asymmetric rotor structure, in order to further improve modeling accuracy, proposes nonlinear analytical model based on four magnetization curves.Secondly, analyzes the mechanism of flux freely switch and magnetic saturation of the stator and rotor tooth, determine the optimal selection principle of the stator and rotor yoke, using the finite element simulation verify principle of selecting reasonable.To investigate the structural parameter of effect torque ripple on flux freedom to switch,optimization and analysis these structural parameters by finite element simulation, to seek the optimal structural parameters. Study have shown that different stator and rotor arc have greater impact on the torque, the finite element method is used to analyze the motor, deduce the stator and rotor arc optimal ratio.Thirdly, when used asymmetric half-bridge power converion circuit driving switched reluctance motor with asymmetric rotor structure, has the problem of torque ripple are prominent, the paper proposes a program use passive boost converter driving switched reluctance motor with asymmetric rotor structure for this problem. Analysis working principle of passive boost converter, build the simulation model based on Matlab, verifying rationality of use use passive boost converter driving switched reluctance motor with asymmetric rotor structure.Fourthly, research on the principle of torque sharing function, and proposes thetorque sharing function with negative torque compensator, Matlab simulation shows that it can not effectively prevent torque ripple when the motor high-speed running. In order to solve these problems, study on current and torque curves when the motor high-speed running and analyze the cause of this problem, proposes new control strategy that combining angle position control with torque sharing function, and through simulation verify the effect that use new control strategy suppressing torque ripple.Finally, design the test method to complete static characteristic test of switched reluctance motor with asymmetric rotor structure, and compare with simulation date to verify the resonableness of the motor design.