In order to improve the transient and static performances of power following system in series hybrid electric vehicle (SHEV), this paper presents a delay-dependent MIMO robust control strategy. The control scheme coordinates the engine and the generator in the auxiliary power unit (APU) to reach the optimal speed and torque synchronously to output the required power. By the way of Pade approximation and multiple linear regression analysis, the delay time uncertainty in engine torque response is emphatically analyzed, which improves the accuracy of the engine torque model. The stability of the system is ensured theoretically by the Lyapunov Stability Theory and a sufficiently robust stability condition is established in terms of the linear matrix inequality (LMI). To avoid the problem of power reverse undershoot, a method of directly limiting the generator torque command is adopted, which is analyzed to not affect the stability of the system. The effectiveness and practicability of the proposed control strategy are demonstrated through numerical simulations and experiments.

中文翻译：

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串联混合动力汽车辅助动力单元功率跟随系统的延迟相关MIMO鲁棒控制

为了提高串联混合动力汽车(SHEV)动力跟随系统的瞬态和静态性能，本文提出了一种延迟相关的MIMO鲁棒控制策略。该控制方案协调辅助动力装置（APU）中的发动机和发电机，同步达到最佳转速和扭矩，输出所需功率。通过Pade逼近和多元线性回归分析，重点分析了发动机扭矩响应的延迟时间不确定性，提高了发动机扭矩模型的准确性。李雅普诺夫稳定性理论在理论上保证了系统的稳定性，并根据线性矩阵不等式（LMI）建立了足够稳健的稳定性条件。为避免功率反向下冲问题，分析采用直接限制发电机转矩指令的方法不影响系统的稳定性。通过数值模拟和实验证明了所提出的控制策略的有效性和实用性。