电动汽车无线充电系统效率特性研究

发布时间：2018-05-17 15:04

本文选题：电动汽车 + 无线充电　；参考：《山东大学》2017年硕士论文

【摘要】：电动汽车的大规模普及有助于缓解目前我国面临的空气污染和能源不足的问题。充电桩的不足却大大地阻碍了电动汽车的普及进度。相较于传统的有线充电装置,电动汽车无线充电系统具有占地少、安全度高、智能化水平高等优势,可以加快电动汽车的推广进程。但电动汽车无线充电系统依然面临着额定功率较小,系统效率较低的问题,对电动汽车无线充电系统传输特性的研究具有重要的现实意义。本文通过对谐振式电动汽车无线充电系统的原理研究,找到影响系统传输功率特性和效率特性的相关参数。通过对各个参数与系统功率和系统效率的关系曲线的分析研究,找到影响传输性能最重要的两个因素:磁耦合结构和系统控制策略。借助ANSYS电磁仿真软件对不同线圈形状、不同线圈尺寸、有无磁芯等结构的磁耦合机构进行建模,并绘制出在磁耦合机构发生水平偏移时耦合系数的改变情况。筛选出性能较好的磁耦合结构,为实验平台的搭建提供指导。分别对调压式控制策略、调频式控制策略、调占空比式控制策略的无线充电系统建立Simulink仿真模型,得到不同控制策略下系统的传输特性曲线。重点对采用调频策略时,高耦合系数下和低等效负载阻值下出现的功率传输曲线和效率传输曲线的频率分裂现象加以研究。在实验平台的搭建过程中,本文详细论述了直流斩波环节、全桥逆变环节、磁耦合机构、高频整流环节、功率开关管驱动电路的设计过程,并针对电感磁芯材料、二极管型号、功率开关管型号、线圈导线的选择做了分析和说明。选用STM32f407芯片开发系统的控制电路,并通过无线通信系统连接本装置的控制系统与车载电池管理系统(BMS)。在实验环节,本文搭建的样机在20cm垂直间隔下,最大传输功率达到了 6kW,最大传输效率达到90%左右。并通过实验对前文有关磁耦合结构和控制策略部分的仿真结论进行了验证,对比三种控制策略下的系统传输性能并提出需要进一步提高和完善的方法。
[Abstract]:The large-scale popularization of electric vehicles helps to alleviate the problem of air pollution and energy shortage in our country. The shortage of the charging pile has greatly hindered the popularization of electric vehicles. Compared with the traditional cable charging device, the electric vehicle wireless charging system has the advantages of less land occupation, high safety and higher intelligence. In order to accelerate the promotion process of electric vehicles, the wireless charging system of electric vehicles still faces the problem of low rated power and low system efficiency. It is of great practical significance to study the transmission characteristics of the wireless charging system of electric vehicles. This paper finds the influence system through the study of the principle of the wireless charging system of the resonant electric vehicle. Through the analysis and study of the relation curves of the power and efficiency of the system, the two factors that affect the transmission performance are found: the magnetic coupling structure and the system control strategy. With the aid of ANSYS electromagnetic simulation software, the shape of different coils, the size of the coils, and the magnetic field are magnetic. The magnetic coupling mechanism of the core structure is modeled and the coupling coefficient changes when the magnetic coupling mechanism has horizontal migration. The magnetic coupling structure with better performance is selected to provide guidance for the construction of the experimental platform. The wireless charging system of the control strategy, the FM control strategy and the air ratio control strategy are respectively used. The Simulink simulation model is established and the transmission characteristic curve of the system under different control strategies is obtained. The focus is on the study of the power transmission curve and the frequency splitting phenomenon of the efficiency transmission curve under the high coupling coefficient and low equivalent load when the frequency modulation strategy is adopted. The design process of DC chopper link, full bridge inverter link, magnetic coupling mechanism, high frequency rectifier link, power switch tube drive circuit, and the selection of inductor core material, diode model, power switch tube model and coil conductor are analyzed and explained. The control circuit of STM32f407 chip development system is selected, and the wireless communication system is adopted. In the experiment link, the maximum transmission power of the prototype is up to 6kW and the maximum transmission efficiency reaches about 90% at the 20cm vertical interval, and the simulation conclusions about the magnetic coupling structure and the control strategy part of the previous article are verified by the experiment, and the contrast three is compared. The transmission performance of the system under different control strategies is proposed.
【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U469.72;TM724

【相似文献】