船用天然气发动机电子节气门自适应高阶滑模控制

Adaptive high order-sliding mode control of the electronic throttle for marine natural gas engines

针对船用天然气发动机电子节气门非线性控制问题以及高阶滑模控制存在的边界难以估计问题,提出了一种基于高阶滑模理论的节气门自适应控制算法,设计了基于系统相平面轨迹收敛过程的自适应策略,为了增加控制算法的实用性,在自适应策略的基础上设计了检测区域,通过判断系统状态与该区域的相对位置双向调节控制增益,以防止增益过大而导致控制精度降低、控制能量浪费的问题;同时,采用鲁棒微分估计器,对不可观测量进行估计;最后,设计3种测试方案,将该算法与传统高阶滑模算法进行实验对比。实验结果表明:在阶跃信号下,该算法使系统响应速度提高35%,稳态误差均方根减小37.5%;在正弦信号下,系统最大稳态误差和稳态误差均方根分别减小30%和22%。

The electronic throttle of marine natural gas engines belongs to the category of nonlinear control.And the boundary of high-order sliding mode control is difficult to estimate.To address this issue,a novel adaptive high-order sliding mode control algorithm is proposed.An adaptive strategy based on the phase plane trajectory convergence process is designed.To increase the practicability of the control algorithm,the detection region is designed based on the adaptive algorithm.The control gain is dual-directional regulation by judging the relative position of the phase trajectory and the detection region to prevent the control accuracy from reducing due to excessive gain.Especially,a robust differentiator is used to estimate the derivative of the sliding variable in the controller.Finally,three test schemes are designed to compare the algorithm with the traditional high-order sliding mode algorithm.Experimental results show that the proposed algorithm can improve the system response speed by 35%and reduce the root mean square error by 37.5%under the step signal.For the sinusoidal signal,the maximum steady-state error and the root mean square of steady-state error are reduced by 30%and 22%,respectively.