最优转矩法因其所需测量状态较少、易于实现的特点,被广泛应用于风力机的最大功率点跟踪(Maximum power point tracking,MPPT)控制.传统的最优转矩法只考虑系统的稳态工作点,依靠系统本身的特性进行转速调节,在一定程度上限制了转速调...最优转矩法因其所需测量状态较少、易于实现的特点,被广泛应用于风力机的最大功率点跟踪(Maximum power point tracking,MPPT)控制.传统的最优转矩法只考虑系统的稳态工作点,依靠系统本身的特性进行转速调节,在一定程度上限制了转速调节速度.本文使用滑模变结构控制的思想,在最优转矩法的基础上设计得到一种变结构控制器,增大了转速跟踪过程中的不平衡转矩,缩短了系统的调节时间.仿真结果表明本文提出的改进方法可以获得良好的转速跟踪效果,从而提高风力机的风能捕获效率.展开更多
预期功能安全的提出,使得传统的自动紧急制动系统的安全性受到了挑战。为此,本文中利用基于系统理论过程分析(systems-theoretic process analysis,STPA)方法得到了自动紧急制动系统的预期功能安全要求,在传统的自动紧急制动系统基础上...预期功能安全的提出,使得传统的自动紧急制动系统的安全性受到了挑战。为此,本文中利用基于系统理论过程分析(systems-theoretic process analysis,STPA)方法得到了自动紧急制动系统的预期功能安全要求,在传统的自动紧急制动系统基础上增加了感知盲区安全车速规划策略。然后基于盲区场景下车辆与行人相遇运动学模型,构造盲区安全车速公式。接着设计加入非线性干扰观测器的速度滑模控制器,对该速度进行跟踪控制,最后在CarSim与Simulink联合平台上开展仿真试验,比较此系统与没有增加预期功能安全要求的自动紧急制动系统的安全性,并进一步在硬件在环仿真试验台上验证。结果表明,考虑预期功能安全的自动紧急制动系统能有效降低行人碰撞风险,并确保车辆安全通过盲区的行驶效率。展开更多
The problem of robustifying linear quadratic regulators （LQRs） for a class of uncertain affine nonlinear systems is considered. First, the exact linearization technique is used to transform an uncertain nonlinear sy...The problem of robustifying linear quadratic regulators （LQRs） for a class of uncertain affine nonlinear systems is considered. First, the exact linearization technique is used to transform an uncertain nonlinear system into a linear one and an optimal LQR is designed for the corresponding nominal system. Then, based on the integral sliding mode, a design approach to robustifying the optimal regulator is studied. As a result, the system exhibits global robustness to uncertainties and the ideal sliding mode dynamics is the same as that of the optimal LQR for the nominal system. A global robust optimal sliding mode control （GROSMC） is realized. Finally, a numerical simulation is demonstrated to show the effectiveness and superiority of the proposed algorithm compared with the conventional optimal LQR.展开更多
This paper presents a design of continuous-time sliding mode control for the higher order systems via reduced order model. It is shown that a continuous-time sliding mode control designed for the reduced order model g...This paper presents a design of continuous-time sliding mode control for the higher order systems via reduced order model. It is shown that a continuous-time sliding mode control designed for the reduced order model gives similar performance for thc higher order system. The method is illustrated by numerical examples. The paper also introduces a technique for design of a sliding surface such that the system satisfies a cost-optimality condition when on the sliding surface.展开更多
文摘最优转矩法因其所需测量状态较少、易于实现的特点,被广泛应用于风力机的最大功率点跟踪(Maximum power point tracking,MPPT)控制.传统的最优转矩法只考虑系统的稳态工作点,依靠系统本身的特性进行转速调节,在一定程度上限制了转速调节速度.本文使用滑模变结构控制的思想,在最优转矩法的基础上设计得到一种变结构控制器,增大了转速跟踪过程中的不平衡转矩,缩短了系统的调节时间.仿真结果表明本文提出的改进方法可以获得良好的转速跟踪效果,从而提高风力机的风能捕获效率.
文摘预期功能安全的提出,使得传统的自动紧急制动系统的安全性受到了挑战。为此,本文中利用基于系统理论过程分析(systems-theoretic process analysis,STPA)方法得到了自动紧急制动系统的预期功能安全要求,在传统的自动紧急制动系统基础上增加了感知盲区安全车速规划策略。然后基于盲区场景下车辆与行人相遇运动学模型,构造盲区安全车速公式。接着设计加入非线性干扰观测器的速度滑模控制器,对该速度进行跟踪控制,最后在CarSim与Simulink联合平台上开展仿真试验,比较此系统与没有增加预期功能安全要求的自动紧急制动系统的安全性,并进一步在硬件在环仿真试验台上验证。结果表明,考虑预期功能安全的自动紧急制动系统能有效降低行人碰撞风险,并确保车辆安全通过盲区的行驶效率。
基金supported by the Doctoral Foundation of Qingdao University of Science and Technology(0022330).
文摘The problem of robustifying linear quadratic regulators （LQRs） for a class of uncertain affine nonlinear systems is considered. First, the exact linearization technique is used to transform an uncertain nonlinear system into a linear one and an optimal LQR is designed for the corresponding nominal system. Then, based on the integral sliding mode, a design approach to robustifying the optimal regulator is studied. As a result, the system exhibits global robustness to uncertainties and the ideal sliding mode dynamics is the same as that of the optimal LQR for the nominal system. A global robust optimal sliding mode control （GROSMC） is realized. Finally, a numerical simulation is demonstrated to show the effectiveness and superiority of the proposed algorithm compared with the conventional optimal LQR.
文摘This paper presents a design of continuous-time sliding mode control for the higher order systems via reduced order model. It is shown that a continuous-time sliding mode control designed for the reduced order model gives similar performance for thc higher order system. The method is illustrated by numerical examples. The paper also introduces a technique for design of a sliding surface such that the system satisfies a cost-optimality condition when on the sliding surface.
