【作者】 宋雪桦；

【导师】 袁银男；

【作者基本信息】 江苏大学 ， 动力机械及工程， 2011， 博士

【摘要】 柴油发动机由于具有油耗低、功率大、扭矩大等特性,越来越广泛地应用于交通运输中。随着社会的进步,车用发动机这一传统的动力装置出现了许多新的挑战,表现为动力性、经济性、耐久性和排放等方面必须满足更高的要求,而现代科技的飞速发展,使电子控制技术成为改善发动机性能的重要手段。因此,研究开发出具有自主知识产权且符合国情的柴油机控制系统,对提高我国车用柴油机自主开发能力和市场竞争能力,保证车用动力产业持续、稳定和健康发展具有重要意义。作为车用柴油机的重要应用领域,内燃机车出于牵引功率较大,不受电力系统故障的影响,具有稳定发展的潜力。论文针对16缸柴油发动机电控系统研究了基于车载网络CAN总线的分布式结构、控制策略和系统的软硬件,进行了详细设计,并经发动机台架实验获得验证。为了进一步提高车载网络通信速度、提高网络容错和纠错能力,论文还研究了高速FlexRay通信网络,并设计各节点的硬件和软件,最终整合成高速分布式控制系统。论文在对车用电控系统发展现状、关键技术及未来趋势的基础上,展开了下述研究工作：(1)研究多缸柴油机分布式系统构架。通过分析现有乍载网络结构特点、柴油机对电控系统的需求,针对机车多缸柴油发动机提出了基于CAN总线的主-从电控单元(ECU)的系统构架,创造性的采用两个具有完全相同软、硬件结构的ECU,研制成主-从ECU的发动机分布式控制系统,通过设置ECU所在物理位置相应I/O口线电平高低,自动识别ECU的主-从身份。(2)分布式控制系统软件和硬件设计。分析了16缸柴油机分布式控制系统硬件工作原理,研究了主要器件的选型并设计了主要硬件电路,设计了CAN网络通信接口和网络通信协议,对系统软件做了整体规划。(3)分布式发动机控制策略的研究。根据机乍柴油机工作特性,设计了整体控制策略和分模块控制策略,主要控制包括转速采集、工况判别、转速控制、励磁控制和故障诊断五大模块。基于发动机硬件系统对分布式主-从发动机电控单元控制软件底层和应用层设计做了详细分析,包括主从ECU位置确定、喷油时间同步原理、主ECU的系统软件流程、从ECU的系统软件流程、发动机控制的数据和指令通信协议设计。设计了转速计算、最大油量限制、供油触发参数计算、故障诊断设计、排放控制等算法。(4)基于高速FlexRay网络的分布式控制系统的研究。为适应粒下一代高速车载网络的需求,特别是实现车联网技术与发动机系统的接入,论文进一步研究了高速FlexRay总线网络的发动机分布式控制系统,包括FlexRay网络系统的特点,数据帧结构定义,时间同步机制,FlexRay系统的主—从ECU的同步机制。更新设计了带有FlexRay总线控制器和总线驱动器的电控单元,研究了通信协议,并实现了分布式控制系统。(5)分布式控制系统试验研究。对基于CAN网络的主-从发动机控制系统做了分项测试和台架测试实验,通过对主-从ECU系统进行实验标定,得到实验数据。测试表明,主-从ECU控制系统可稳定实施对多缸柴油机的联合控制,发动机在预定的各实验工况转速比较稳定,误差可控制在0.5%以内,通过进一步优化标定可以实现更好的效果。搭建了两个节点的FlexRay控制系统试验平台。实验表明,在两个或更多时槽中,实现了比CAN速度更高和信息量更多的实时数据交换,系统最高通信速度可以达到10 Mbit/s。同时采用FlexRay定时高速发送曲轴位置同步信号,可取消基于CAN总线分布式系统中的同步信号专递专用接口线,进一步简化系统,提高了系统的可靠性,并为新一代车载网络提供了一种可资借鉴的解决方案。更多还原

【Abstract】 For the advantage of low fuel consumption, low emissions, high-power, high-torque, diesel engines become more and more widely used in transportation. Electronic control system is widely used to get better engine performance, through the diesel engine’s electronic control to meet various application requirements. With the rapid development of modern technology, the traditional engine of the locomotive power unit is facing increacing challenges, such as the locomotive engine power, economy. It also has a higher demand on durability and emissions, thus the development of electronic diesel engine control system with independent intellectual rights and China’s national conditions are very important, which would improve the capacity of independent development and market competitiveness of China’s automobile, and ensure sustained, stable and healthy development of industrial diesel engines.As the larger traction power, locomotives generally used more than eight-cylinder diesel engine with electronic fuel injection system. In this paper, CAN-based distributed architecture design is used in 16-cylinder diesel engine electronic control system, detailed descriptions of engine control strategy and the software were made, and also the results of the engine bench test were analyzed. To further enhance the communication speed, this paper has studied high-speed FlexRay communications network, and the hardware and software were designed for the two net nodes. The main works of this paper are as follows:(1) Distributed architecture for multi-cylinder diesel engine has been researched, and the structural characteristics of the network board as well as diesel engine work principle were analyzed in the paper. In viewing of Multi-cylinder engine with high-speed control, CAN-based master-slave electronic control unit (ECU) system architecture was proposed. The two ECUs have the same hardware architecture, which can identify master-slave status of the ECUs by setting the I/O port line level.(2) The system software and hardware have been designed in the paper. By analyzing the hardware work principle of 16-cylinder diesel engine distributed control system, the main hardware circuits were design. The ECU has CAN communication interface, which can achieve the real-time data exchange via the CAN bus. The system software mainly includes the modules:speed acquisition, condition identification, speed control, excitation control and fault diagnosis.(3) According to the needs of the engine control process, the paper described the detail designs of control software infrastructure and application-layer for the distributed master-slave electronic control units. which includes the master-slave ECU location determination. fuel injection time synchronization. the master-ECU’s overall software process, the slave-ECU’s overall software process, engine control data and instruction communications protocol. It also has a design of the main engine control strategies, such as speed calculation, the maximum fuel limit, fuel trigger parameter calculation, emission control and fault diagnosis.(4) In order to further improve the communication speed and meet real-time exchange of large volumes of data, high-speed FlexRay network based on time-division multiplexing approach were used. The paper analyzed the characteristics of the FlexRay bus, the frame structure definition, time synchronization mechanism and the system master-slave synchronization principle. The FlexRay bus controller and drivers were added into the ECUs on the base of the original hardware, which has achieved the hardware and node design. The initialization of FlexRay was designed, and two node FlexRay communication design was implemented.Finally, to verify the design of the system, the sub-tests and bench tests were completed on the master-slave engine control system based on the CAN network and the experimental data were obtained through calibration experiments of the master-slave ECU system. The results of the experiments show that the master-slave ECU control system can stably implement the multi-cylinder diesel engine joint control and the engine has the stable speed at predetermined experimental conditions, as well as the error could be limited in 0.5%. Calibrations can be achieved by further optimization for better results.The two node FlexRay interface communication was built in the paper, and data exchange was simulated as engine. The results of the experiment show that in two slots, sender and receiver can achieve real-time data exchange and the maximum operating speed can up to lOMbit/s, which provides a solution for the follow-up replacement of the CAN.更多还原