新型励磁模式开关磁阻轮毂电机优化设计及电回馈控制策略研究

Some key theory problems of the in-wheel switched reluctance motor (SRM) are appeared as the special structure arrangement and regenerative braking requirement of the electric vehicle, such as structure design and electrical feedback control, although the SRM drive system becomes a very competitive motor with its unique advantages. Therefore this project focuses on a novel two-phase synchronous exciting mode switched reluctance motor (SESRM) proposed by the author currently and researches the configuration optimizing, magnetic-field coupling analyzing and electricity generating control strategy respectively. Firstly, a multi-objective simultaneous optimization strategy is proposed by establishing an objective function with weight factors in order to optimize the average torque, efficiency and torque density of the SESRM. Then the magnetic-field distribution and changing regulation of the electromagnetic parameters are analyzed by the finite element method, and the effect theory of the magnetic-field coupling characteristics to electromagnetic parameters and torque performance is indicated and the nonlinear electromagnetic mode for the novel SESRM is established. Finally, the optimizing regenerative braking torque model is obtained based on the novel SESRM after analyzing brake dynamic characteristics of the electric vehicle, and the optimizing objective function of the in-wheel SESRM is established to develop the electricity generating strategy of the SESRM. The project will make a breakthrough in the basic theory area of analyzing electromagnetic parameters performance and electricity generating control for the novel SESRM.

开关磁阻电机以其独特优势成为电动汽车极具竞争力的驱动机种，但由于轮毂电机在整车中的特殊结构布置及车辆再生制动要求，其结构设计及电回馈控制成为亟待解决的关键科学问题。本项目针对申请者前期提出的一种新型两相同步对称励磁模式开关磁阻电机，拟利用理论研究与实验验证相结合的方法对其结构优化、磁场耦合特性分析及电回馈控制策略问题进行重点研究。首先，以平均转矩、效率及转矩密度为性能指标，引入多指标优化权重系数建立结构参数优化目标函数，提出一种实现电机多性能指标同步提升的结构参数优化策略；然后利用数值分析方法研究新型模式电机电磁参数变化规律，揭示磁路耦合特性对电磁参数影响机理，建立其非线性电磁模型；最后，分析电动汽车制动动力学特性，以其再生制动系统最优制动转矩为约束条件建立轮毂电机输出功率优化目标函数，实现电回馈功率优化控制。本项目将在新型模式磁阻电机电磁参数特性、电回馈模式控制方面取得一定基础理论突破。

基于电动汽车轮毂驱动方式，设计了四相16/20极外转子开关磁阻轮毂电机，利用静态电磁场数值模拟方法对其主要电磁参数进行了计算分析；基于正交试验设计和极差分析法，分析了电机主要结构参数对电机平均转矩、转矩脉动、效率和转矩密度的影响规律；以电机关键性能指标同步优化为目标，基于主要结构参数对各性能指标的灵敏度分析，建立了轮毂电机结构参数多指标同步优化目标函数，在满足开关磁阻轮毂电机布置形式及结构约束条件基础上，实现了电机结构参数的多指标同步优化。在MATLAB/Simulink环境下建立了开关磁阻发电机系统非线性动态模型，基于开关磁阻发电机相电流波形的分析，建立了低速电流滞环和高速单脉冲两种控制模型。为了提高电动汽车的乘坐舒适性、续航里程和电池寿命，提出了转矩平顺系数、输出功率和电流平滑系数三个优化指标；通过离线数据采集，分别分析了开关磁阻发电机在低速和高速两种运行工况条件下各自控制参数对各优化指标的影响；为提高电动汽车用开关磁阻发电机驱动系统的综合性能，提出了一种多指标同步优化控制策略，构建了多指标优化函数，设计了基于可变开通角、关断角的多指标优化控制器。建立了电动汽车动力学模型；设计了基于制动强度大小分区的前、后轮制动力分配方案；提出了基于最大能量回收的再生制动力分配方案；基于建立的电动汽车再生制动系统模型，对三种常规制动工况进行了研究，检验了优化的开关磁阻发电机在再生制动系统的制动效果。