永磁电机驱动的刮板输送机主传动系统机电耦合扭振动态分岔研究

Dynamic bifurcation analysis of electro-mechanical coupled torsional vibration for main transmission system of scraper conveyer driven by permanent magnet motor

采用大功率交流永磁电机直接驱动刮板输送机能够减少中间传动环节,达到有效提高系统工作可靠性和减少能耗的目的,是现今大功率机电装备的发展趋势。以永磁电机驱动的刮板输送机为研究对象,考虑永磁电机直接驱动形式下刮板输送机主传动系统的扭振失稳现象以及该系统复杂机电耦合的特点,首先根据拉格朗日-麦克斯韦方程建立系统全局机电耦合动力学模型,并据此运用Hurwitz判据研究一类非线性摩阻作用下主传动系统Hopf分岔特性,给出系统稳定域;在刮板输送机主传动系统扭振失稳边界点,采用中心流形理论对系统动力学模型进行降维,并依据规范型理论给出系统Hopf分岔类型与非线性摩阻系数的关系,数值仿真结果验证了理论分析的正确性。研究结果可为永磁电机驱动下刮板输送机系统的稳定运行提供理论依据。

It is an effective method to adopt a high-power alternating current(AC)permanent magnet motor to directly drive a scraper conveyer system,decrease its intermediate transmission links and achieve the aim of improving the system reliability and reducing its energy consumption.Here,a scraper conveyer driven by a permanent magnet motor was taken as a study object.Firstly,considering the torsional vibration instability of its main transmission system and its complex electro-mechanical coupled feature,the system’s global electro-mechanical coupled dynamic model was constructed with Lagrange-Maxwell equations.Then,Hopf bifurcation characteristics of the main transmission system under the action of a class of nonlinear friction damping were investigated and the system stable region was obtained with Hurwitz criterion.At the main transmission system’s instability boundary point,the center manifold theory was adopted to reduce the dimension of the system dynamic model,and the relationship between Hopf bifurcation type and nonlinear friction damping coefficient was deduced using the normative theory.The correctness of the theoretical analysis was verified with numerical simulation results.The study results provided a theoretical basis for the stable operation of scraper conveyers driven by permanent magnet motors.