EPS电机控制器的设计

摘要

由于电动助力转向系统具有环保节能、助力特性可调、安全性高等优点，许多汽车企业和研究单位已经将其做为重点研发项目之一，其中，电子控制器硬件开发和控制软件是其核心技术之一。

本文首先分析了各种助力转向系统的特点，重点研究了电动助力转向系统的结构和动力学模型。

本文重点设计了电动助力转向系统的控制器硬件及控制软件。硬件设计方面主要包括：选取了飞思卡尔 MC9S12 系列单片机作为 EPS 系统 CPU，设计了单片机最小系统电路（包括时钟电路、滤波电路、电源电路、复位电路等）；采用 LM2576 芯片设计了稳压电源电路；方向盘转矩传感器信号和车速信号调理电路、助力电机驱动电路以及通信电路等。助力电机驱动电路由电机专用驱动芯片 TD340 驱动；通信电路主要由串口通信和 CAN 总线通信组成，实现与 PC 机和整车通信；控制软件方面主要编写了单片机的 A/D转换程序、PWM 模块和脉冲捕捉模块程序以及相关寄存器配置方法。

为了验证控制器硬件和软件的可靠性，在本设计中进行了实验研究，主要包括无助力与有助力对比、方向盘回正控制等试验，结果表明，控制器硬件部分性能良好、工作稳定可靠；软件控制效果较好，助力特性符合设计要求。转向系统稳定性较好，同时方向盘上无明显抖动，手感良好，为下一步的装车试验做好了准备。

关键词：EPS；传感器；单片机；电机；电路；

ABSTRACT

Because of electric power steering system has the environmental protection and energy saving dynamical, characteristics adjustable security advanced advantage, Many automobile enterprises and research units already use this as one of the key research projects, Including electronic controller hardware development and control software is its core technical one.

This paper first analyzes the characteristics of various steering system, Focus on the electric power steering system structure and dynamic model.

This paper puts emphasis on the design the electric power steering system controller hardware and software and hardware design control mainly includes; Select freescale MC9S12 series microcontroller as EPS system CPU, Designed the single chip minimize system clock circuit circuit (including filter circuits power circuit reset circuit etc.); Using the LM2576 chip design firm V oltage circuit was designed The steering wheel torque sensor signal and speed signal regulate circuit power motor drive circuit and communication circuit to boost by motor driving circuit for TD340 driver drive chip; Communication circuit consists mainly of serial communication and thecan bus communication composition, Realization and PC and vehicle communication; The control software is mainly wrote MCU A/D conversion process PWM module and pulse capture module procedures and related registers collocation method.

In order to verify the reliability of the controller hardware and software, And carry through experimental study on test-bed, Including the contras of without power and have power, The experimental results show that the controller hardwareperformance is good, Stable and reliable; Software control effect is good, Dynamical characteristics comply with the design requirements. Steering system stability is good, And the steering wheel without obvious jitter, Steering feel is good,And getting ready for the loading test of the next.

Keywords: Electric power steering; Sensor; Single chip; Electrical machine; Electrial circuit;