Transient control law ensures that the aeroengine transits to the command operating state rapidly and reliably. Most of the existing approaches for transient control law design have complicated principle and arithmeti...Transient control law ensures that the aeroengine transits to the command operating state rapidly and reliably. Most of the existing approaches for transient control law design have complicated principle and arithmetic. As a result, those approaches are not convenient for application. This paper proposes an extrapolation approach based on the set-point parameters to construct the transient control law, which has a good practicability. In this approach, the transient main fuel control law for acceleration and deceleration process is designed based on the main fuel flow on steady operating state. In order to analyze the designing feature of the extrapolation approach, the simulation results of several different transient control laws designed by the same approach are compared together. The analysis indicates that the aeroengine has a good performance in the transient process and the designing feature of the extrapolation approach conforms to the elements of the turbofan aeroengine.展开更多
针对最大功率点跟踪(Maximum power point tracking, MPPT)算法中传统滑模控制存在收敛速度慢、抖振显著等不足,提出一种基于RBF神经网络的光伏系统非线性反步积分滑模(Nonlinear backstepping integral sliding mode control, NBISMC)...针对最大功率点跟踪(Maximum power point tracking, MPPT)算法中传统滑模控制存在收敛速度慢、抖振显著等不足,提出一种基于RBF神经网络的光伏系统非线性反步积分滑模(Nonlinear backstepping integral sliding mode control, NBISMC)最大功率点跟踪策略。首先,采用RBF神经网络对各种气象条件下的光伏电池输出电压进行预测;其次,设计非线性积分滑模面以改善传统滑模控制存在稳态误差及超调量大的问题;最后,设计新型指数趋近律,在加快收敛速度的同时有效削弱了系统高频抖振;通过Lyapunov函数分析非线性反步积分滑模控制的可达性与稳定性,并在静态、动态和遮光条件下进行仿真试验。仿真试验结果表明,在温度和光照强度发生变化的工况下,相比于传统滑模控制,基于RBF神经网络的非线性反步积分滑模控制能在各种气象条件下快速、准确地跟踪光伏系统最大功率点,具有较强的鲁棒性。展开更多
随着如今智能驾驶的快速发展,线控转向系统(steering-by-wire,SBW)作为其关键的组成部分,正成为汽车技术创新的核心领域之一。相较于传统机械转向系统,SBW通过电子化控制取代方向盘与执行机构间的机械连接,并借助控制器模拟路感反馈至...随着如今智能驾驶的快速发展,线控转向系统(steering-by-wire,SBW)作为其关键的组成部分,正成为汽车技术创新的核心领域之一。相较于传统机械转向系统,SBW通过电子化控制取代方向盘与执行机构间的机械连接,并借助控制器模拟路感反馈至驾驶员。为了模拟出适合驾驶员的路感,通过Matlab/Simulink和Carsim平台,构建了线控转向系统的车辆模型。然后通过计算轮胎上产生的回正力矩,同时加上电动助力转向系统(electric power steering system,EPS)中的助力力矩,得到最后的路感力矩。同时,为了实现路感电流的精确跟踪控制,引入了滑模变结构控制技术。为了缓解系统抖振问题,在滑模控制策略中整合了一种新型趋近律。仿真结果验证了滑模变结构控制在实现路感反馈功能上的优越性。展开更多
基金support of Aeronautical Science Foundation of China (2011ZB51019)
文摘Transient control law ensures that the aeroengine transits to the command operating state rapidly and reliably. Most of the existing approaches for transient control law design have complicated principle and arithmetic. As a result, those approaches are not convenient for application. This paper proposes an extrapolation approach based on the set-point parameters to construct the transient control law, which has a good practicability. In this approach, the transient main fuel control law for acceleration and deceleration process is designed based on the main fuel flow on steady operating state. In order to analyze the designing feature of the extrapolation approach, the simulation results of several different transient control laws designed by the same approach are compared together. The analysis indicates that the aeroengine has a good performance in the transient process and the designing feature of the extrapolation approach conforms to the elements of the turbofan aeroengine.
文摘针对最大功率点跟踪(Maximum power point tracking, MPPT)算法中传统滑模控制存在收敛速度慢、抖振显著等不足,提出一种基于RBF神经网络的光伏系统非线性反步积分滑模(Nonlinear backstepping integral sliding mode control, NBISMC)最大功率点跟踪策略。首先,采用RBF神经网络对各种气象条件下的光伏电池输出电压进行预测;其次,设计非线性积分滑模面以改善传统滑模控制存在稳态误差及超调量大的问题;最后,设计新型指数趋近律,在加快收敛速度的同时有效削弱了系统高频抖振;通过Lyapunov函数分析非线性反步积分滑模控制的可达性与稳定性,并在静态、动态和遮光条件下进行仿真试验。仿真试验结果表明,在温度和光照强度发生变化的工况下,相比于传统滑模控制,基于RBF神经网络的非线性反步积分滑模控制能在各种气象条件下快速、准确地跟踪光伏系统最大功率点,具有较强的鲁棒性。
文摘随着如今智能驾驶的快速发展,线控转向系统(steering-by-wire,SBW)作为其关键的组成部分,正成为汽车技术创新的核心领域之一。相较于传统机械转向系统,SBW通过电子化控制取代方向盘与执行机构间的机械连接,并借助控制器模拟路感反馈至驾驶员。为了模拟出适合驾驶员的路感,通过Matlab/Simulink和Carsim平台,构建了线控转向系统的车辆模型。然后通过计算轮胎上产生的回正力矩,同时加上电动助力转向系统(electric power steering system,EPS)中的助力力矩,得到最后的路感力矩。同时,为了实现路感电流的精确跟踪控制,引入了滑模变结构控制技术。为了缓解系统抖振问题,在滑模控制策略中整合了一种新型趋近律。仿真结果验证了滑模变结构控制在实现路感反馈功能上的优越性。
