直接横摆力矩控制（DYC）通过制动力或驱动力在车轮上的分配产生维持车辆稳定行驶所需的附加横摆力矩，以提高车辆在极限工况下的行驶稳定性。本文的DYC控制采用常用的递阶结构，上层控制器根据横摆角速度实际值与目标值之差确定维持车辆稳定行驶所需的目标横摆力矩，而下层控制器通过车轮的滑移率控制实现该横摆力矩。基于滑模变结构控制理论设计了作为上层控制器的二阶滑模控制器（SOSM），其控制输入为附加横摆力矩。附加横摆力矩依靠制动部分车轮实现，并由下层控制器进行车轮滑移率调节。在MATLAB /Simulink和ve-DYNA车辆动力学仿真环境下建立了汽车DYC硬件在环和驾驶员在环试验台，并采用该仿真平台对所提出的DYC控制策略进行了评价。结果表明该控制算法在极限工况下可较好地提高车辆的行驶稳定性，极大地提高了车辆的主动安全性能。

Direct Yaw-moment Control(DYC), by distributing braking forces or driving forces on wheels, generates the additional yaw-moment needed in maintaining vehicles’ driving stability, so as to improve driving stability under extreme conditions. In this paper, DYC control adopts the frequently-used Hierarchical Structure. The upper controller determines the additional yaw-moment needed in maintaining vehicles’ driving stability according to the difference between the actual yaw rate and the desired yaw rate, while the lower controller realizes the yaw-moment by controlling the wheel slip ratio. A Second Order Sliding Mode(SOSM) controller, which is designed based on the sliding mode control theory, is used as an upper controller. The input of the SOSM controller is the additional yaw-moment. The additional yaw-moment is realized by braking some of the wheels and the wheel slip ratio is regulated by the lower controller. Based the simulation environment of MATLAB/Simulink and ve-DYNA, the Hardware-In-Loop and Driver-In-Loop test platform is built, on which the DYC control strategy is evaluated. The result shows that this control algorithm can farther improve the driving stability of vehicles under extreme conditions and significantly enhance the vehicle’s active safety performance.