【作者】 周亮；

【导师】 朱文；

【作者基本信息】 重庆大学 ， 机械电子工程， 2008， 硕士

【摘要】 电动助力转向系统(EPS)是近几年来兴起的新型动力转向系统。EPS采用电机作为动力源,以微处理器为控制单元,能针对汽车行驶的各种不同工况进行智能控制,达到最理想的助力效果。在转向操作的舒适性、安全性和节能环保等方面具有传统液压助力转向系统无法比拟的优势。本文以无刷直流电机为动力源,以高性能、高可靠性的电动助力转向系统为目标,对其进行了深入的系统的研究。本文针对电动助力转向系统(EPS)的控制原理进行了研究,详细的分析和比较了电动助力转向系统控制策略的原理和实现方法,确定了电机电枢电流法实现助力功能。本文对电动助力转向系统中无刷直流电机控制的核心控制技术进行了研究,深入的探讨了电机相电流和母线电流的关系,提出了一种低成本、精度较高的无刷直流电机相电流检测方案,并结合工程实践给出了母线电流和相电流采样方法;讨论了无刷直流电机的阻尼控制原理,并给出了实际的应用方法;研究了一种新型的PWM控制策略,有效地降低了系统的功耗,提高系统的可靠性。在以上的理论基础上,本文以英飞凌公司的数字信号处理器XC2365和专用三相电机驱动芯片TLE7183为核心设计了EPS无刷直流电机控制器的硬件平台。软件上将模块化设计的思想贯穿到整个EPS控制程序,软件构架清晰合理、层次分明、控制效果好,能够实现不同工况和不同模式下对电机转矩的精确控制。文中对整个系统的架构及硬件电路和驱动软件的实现作了详细的介绍,并给出硬件结构框图及软件部分的程序框图。本文在最后介绍了调试环境和设备,给出了实验数据和波形并对实验结果做了分析和比较。实验结果证明,本文设计的汽车电动助力转向系统中的无刷直流电机控制器具有良好的性能,基本达到预期设计要求,为后续的研究工作提供了很好的基础和借鉴。更多还原

【Abstract】 Electric power steering(EPS) is a newly-developed power steering system in the recent years. EPS uses motor as power source and microprocessor as control unit; it can adopt different intelligent control and achieve the best steering result. EPS can meet all demands of steering performances and has overwhelming advantages on operation, safety and environmental protection comparing with traditional hydraulic power steering system. This dissertation does some embedded investigation focused on the high performance EPS system which is based on brushless motor.This paper includes research of EPS control principle, detailed analyses of implementation methods and theory of EPS control strategy, and finally realize the steering function by using the mothod of motor armature current. This paper also includes research of core control skills of BLDC in EPS, deep discussions of connections of phase current and generatrix current, made a low-cost, high precision brushless DC motor phase current testing programme, combined with engineering practice and given the phase current and generatrix current sampling methods; Discussed the principle of BLDC damping control, and gives practical application; On a new PWM control strategy to reduce the power consumption of the system, improve the reliability of the system.Based on the theory, the EPS designed in this paper takes XC2365 of infineon company as its core control technology and adopts TLE7183 to build drive circuit. The software had developed a strongly-structured program for EPS which can achieve precise control of torque under different situations. System architecture and the design of hardware and software are presented in detail in the text,and the hardware structure and program block are given.At the last of this paper, tests had been done based on this and the result showed that: the BLDC of EPS designed in this paper have good performance. It had laid a soild foundation for further research更多还原