Hardware-in-the-Loop tests have become a key factor in decreasing development time of various drive systems. In this context, high performance test beds, where feedback control plays a major role, are necessary to meet the demanding requirements such as real driving emissions in the automotive industry. Particularly for combustion engine test beds, periodic combustion strokes cause large oscillations in different measurement signals on engine test beds, which causes severe problems since conventional controllers try to compensate for these periodic disturbances. The control settings are a trade-off between fast reference tracking and undesirably strong disturbance rejection, which may compromise test results. An ordinary two-degree-of-freedom (2-DOF) control with flatness-based feedforward control produces relief in separating reference and disturbance behavior but cannot handle input constraints. Thus, a model predictive feedforward controller (MPFFC) in combination with the 2-DOF strategy is introduced for high-dynamic speed control in this contribution. The MPFFC generates optimal input and output trajectories, which respect constraints of the system. Fast reference tracking is achieved without the risk of falsification by high feedback. Comparisons between the proposed method, a simple feedback and a standard 2-DOF controller with a conventional flatness-based feedforward control are performed on a state-of-the-art 4-cylinder engine test bed. The experiments constitute a rare implementation of a MPFFC on a real system and demonstrate its capabilities of separating reference and disturbance response as well as taking advantage of certain situations to even further improve reference tracking speed.

中文翻译：

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内燃机试验台高转速控制的模型预测前馈控制

硬件在环测试已成为减少各种驱动系统开发时间的关键因素。在这种情况下，需要在反馈控制中扮演重要角色的高性能测试台来满足苛刻的要求，例如汽车行业中的实际驾驶排放量。特别是对于内燃机测试台，周期性的燃烧冲程会在引擎测试台上的不同测量信号中引起较大的振荡，这会导致严重的问题，因为常规控制器试图补偿这些周期性的干扰。控制设置是快速参考跟踪与不希望的强干扰抑制之间的权衡，这可能会损害测试结果。具有基于平坦度的前馈控制的普通两自由度（2-DOF）控件可减轻参考和干扰行为的分离，但无法处理输入约束。因此，在这种贡献中，引入了模型预测前馈控制器（MPFFC）与2-DOF策略的组合，以实现高动态速度控制。MPFFC生成最佳的输入和输出轨迹，这些轨迹遵守系统的约束条件。实现了快速参考跟踪，而不会因高反馈而伪造风险。在最新的4缸发动机试验台上，对所提出的方法，简单的反馈和具有传统的基于平面度的前馈控制的标准2自由度控制器进行了比较。