基于BP神经网络的飞轮储能系统主动磁轴承非线性动力学模型  

Nonlinear Dynamic Model of Active Magnetic Bearing in Flywheel System Based on BP Neural Network

作　　者：何海婷 柳亦兵[1] 巴黎明 周传迪 滕伟[1] HE Haiting;LIU Yibing;BA Liming;ZHOU Chuandi;TENG Wei(School of Energy Power and Mechanical Engineering,North China Electric Power University,Changping District,Beijing 102206,China;School of Chemical&Environmental Engineering,China University of Mining and Technology-Beijing,Haidian District,Beijing 100083,China)

机构地区：[1]华北电力大学能源动力与机械工程学院,北京市昌平区102206 [2]中国矿业大学(北京)化学与环境工程学院,北京市海淀区100083

出　　处：《中国电机工程学报》2022年第3期1184-1197,共14页Proceedings of the CSEE

基　　金：河北省科技计划项目(15214307D)。

摘　　要：主动磁轴承(active magnetic bearing,AMB)是飞轮储能系统中实现飞轮转子非接触支撑的核心部件,其对飞轮转子施加的作用力与多种非线性因素相关。采取"两步线性化"方法的传统线性模型抹除了非线性特性,难以准确描述其宽频谱的工作状态,也影响了控制系统的设计精度。针对该问题,文中基于替代映射的观点建立非线性的AMB模型。通过AMB的三维有限元计算模型的参数化计算和BP神经网络训练来获得对应的转移和偏执矩阵,然后建立描述转子位移和绕组电流与作用力之间映射关系的零维非线性动力学模型,并在Matlab/Simulink软件平台仿真实现。计算结果表明,AMB内存在四次高次项、交叉项等复杂非线性特性。与线性模型的对比表明,建立的非线性模型可以更准确描述AMB的非线性特性。该模型对飞轮储能系统仿真和控制系统开发具有一定意义。Active Magnetic Bearing(AMB)is a core part to achieve non-contact support in flywheel energy storage system.Its electromagnetic force to the rotor is related to several nonlinear factors,but a conventional linear model based on“two step linearization”removes nonlinear information.It is not able to express the broadband spectrum working condition,and has negative influence to design accuracy of control subsystem.To solve this problem,a new nonlinear model base on alternative mapping concept was developed.An AMB finite element model was built.Its parametric calculation data were used to train a BP neural network.Weight and threshold matrix from this training was used to build a zero-dimensional nonlinear dynamic model,which can describe relationship from rotor displacement and winding current to forces to rotor.This model was implemented in Matlab/Simulink.Calculation results show there are complex nonlinear characteristics in an AMB,including four order terms and cross terms.A comparison with linear model results shows that this new model is more accurate in AMB’s nonlinear characters.This model is an important support to system simulation and control subsystem development in flywheel energy storage system.

关 键 词：BP神经网络 飞轮储能 主动磁轴承 非线性动力学 

分 类 号：TM91[电气工程—电力电子与电力传动]