针对车载以太网在运行时间同步协议过程中存在的不足, 提出涉及到主时钟仲裁、启动时间加速、冗余路径选择和故障恢复机制的优化方法并采用实物网络测试验证其可行性和有效性.在保证同步精度的前提下, 对这些问题提出优化措施从而使车载时间同步过程始终处于可预测的状态;在运行过程中同步时钟对节点和链路故障具有容错能力并提出同步彻底失效时的容错机制, 从而避免同步故障对正常驾驶产生影响.“,”To improve the time synchronization protocol in automotive environment, this paper proposes optimization methods including master clock arbitration, start-up timing, redundant path selection and fault recovery mechanism. The feasibility and effectiveness of these methods are tested on the real network. Without reducing synchronization accuracy, the optimization methods keep the new time synchronization process in a predictable state. Synchronous clock is fault-tolerant to node and link fault. Moreover, the fault-tolerant mechanism is proposed when synchronization fails completely, so as to avoid the impact of synchronous failure on normal driving.