基于四轮独立全电耦合制动的电动车纵/横向动力学控制研究

As a new configuration, all electric independent driving and braking electric vehicle of four wheels follows the trends of “safety, energy saving and environmental protection” completely. One of its advantages is that the mechanical braking force and regenerative braking force can be adjusted accurately, independently and quickly. The other is that it provides a new way to make full use of ground adhesion for each wheel. So it provides a foundation for optimizing the longitudinal and lateral dynamic control of vehicle. It also provides a new idea for the optimal design of the full electric braking system. But it also brings new problems, such as the increase of wheel rotary inertia and vehicle unsprung mass. This project is proposed based on the problem that needs to be resolved urgently for the dynamic control of all electric independent driving and braking electric vehicle. That is the regulation law for independent all electric coupled brake of four wheels that adopts to the characteristics of the target configuration and its longitudinal/lateral dynamics control. For this, the method of combining theory with practice, the theoretical derivation and analysis, computer simulation and bench test and so on are adopted. The In-depth study for the decoupled brake energy recovery control strategy and vehicle stability control strategy based on the feature of applicable object and the aforementioned results is proposed. The related control algorithms are researched. A software and hardware in the loop test platform will be built. It consists of a 15DOF vehicle dynamics model, online real time development system, sensors and actuators and so on. The research for the key problems is done based on the test platform. Related results can lay theoretical basis for the optimal design of all electric braking system and the application of all electric braking and independent driving in high performance electric vehicles.

全电四轮独立驱动-制动电动车作为一种全新构型，完全符合汽车“安全、节能、环保”的发展趋势，具有各轮机械制动力/再生制动力精确独立快速可调，可充分利用地面附着力的优势，为优化整车纵/横向动力学控制提供了基础，也为全电制动系统的优化设计提供了新思路，但也带来了车轮转动惯量/整车非簧载质量大幅增加等新问题。本项目采取理论与实践相结合的方法，借助理论分析、仿真及台架试验，针对研究对象动力学控制中亟需解决的适应目标构型特征及其纵/横向动力学控制的四轮独立全电耦合制动力调节规律开展应用基础研究，并以此为基础深入探讨适用于目标车型特征的解耦式制动能量回收控制策略、整车稳定性控制策略，研究相应控制算法，搭建由十五自由度车辆模型、在线实时开发系统、传感器、执行器等组成的软硬件在环综合试验平台，分析验证关键科学问题。相关成果可为全电制动系统的优化设计及全电制动和独立驱动技术在高性能电动车中的应用奠定理论基础。

全电四轮独立驱动-制动电动车(AEIDBEV)作为一种全新构型，具有各轮机械制动力/再生制动力精确独立快速可调，可充分利用地面附着力的优势，在对其进行整车纵/横向动力学控制时，通过轮毂电机(IWM)和电子机械制动(EMB)耦合提供所需车轮制动力，这在保证整车操纵稳定性的前提下，可通过控制IWM发电来有效降低整车耗能，为高动力性、高经济性、高操纵稳定性电动车提供解决方案，另外，还可有效降低对EMB工作时间和最大制动力等设计参数的要求，使优化EMB结构成为可能，但也带来了车轮转动惯量/整车非簧载质量大幅增加等影响整车纵/横向动力学控制的问题，因此研究AEIDBEV纵/横向动力学控制中的关键问题对其普及应用具有重要意义。本研究完成内容如下：第一，提出了AEIDBEV总成参数匹配优化流程和整车控制策略，尤其是解耦式制动能量回收(URBS)策略，对其动力性、制动性及节能潜力开展了研究；第二，针对全电驱动-制动电动轮开展了详细研究，提出了一种新型全电驱动-制动电动轮结构，绘制了二维图，搭建了三维模型，并进行了结构分析；第三，搭建了十五自由度AEIDBEV整车动力学仿真模型，基于AVL-Cruise和Matlab搭建了经济性联合仿真平台，基于Carsim和Matlab搭建了整车动力学联合仿真平台，验证了十五自由度AEIDBEV整车动力学仿真模型的精度，完成了EMB电机、IWM电机和电池等关键总成的性能测试，基于测试数据完成了模型参数化；第四，对适用于AEIDBEV的纵/横向动力学控制开展了系统研究，明确了车轮转动惯量增加对制动防抱死系统(ABS)的影响规律和最佳门限值的确定方法，提出了全电耦合ABS控制方案并进行了验证，相关成果在某商用车URBS和ABS开发中应用并开展了整车实验，对AEIDBEV横向动力学稳定性控制开展了质心侧偏角估算、基于质心侧偏角的稳定性判据、电子差速控制及多种横摆稳定性控制方案等研究；第五，搭建了AEIDBEV纵/横向动力学控制硬件在环实验台，通过硬件在环实验进一步验证了研究内容的合理性。相关成果可为全电制动系统的优化设计及全电制动和独立驱动技术在高性能电动车中的应用奠定基础。