This paper presents a nonlinear model predictive control(NMPC) approach based on support vector machine(SVM) and genetic algorithm(GA) for multiple-input multiple-output(MIMO) nonlinear systems.Individual SVM is used ...This paper presents a nonlinear model predictive control(NMPC) approach based on support vector machine(SVM) and genetic algorithm(GA) for multiple-input multiple-output(MIMO) nonlinear systems.Individual SVM is used to approximate each output of the controlled plant Then the model is used in MPC control scheme to predict the outputs of the controlled plant.The optimal control sequence is calculated using GA with elite preserve strategy.Simulation results of a typical MIMO nonlinear system show that this method has a good ability of set points tracking and disturbance rejection.展开更多
三电机卷绕系统是一个强耦合非线性时变系统,存在卷轴半径、转动惯量以及摩擦系数等时变参数,导致张力协同控制精度较低.为了提高卷绕系统模型准确度,实时优化张力协同控制系统的动态性能,提出一种基于改进鲸鱼算法优化的多核最小二乘...三电机卷绕系统是一个强耦合非线性时变系统,存在卷轴半径、转动惯量以及摩擦系数等时变参数,导致张力协同控制精度较低.为了提高卷绕系统模型准确度,实时优化张力协同控制系统的动态性能,提出一种基于改进鲸鱼算法优化的多核最小二乘支持向量机回归(multi-kernel least squares support vector regression prediction model based on an improved whale algorithm optimization,WOA-M-LSSVR)预测模型和基于纵横交叉优化算法(crisscross optimization algorithm,CSO)优化的模型预测张力协同控制系统.根据最小二乘支持向量机回归原理建立多核LSSVR回归模型,并使用改进的自适应鲸鱼算法进行离线优化,得到系统预测模型;根据建立的预测模型,构建自适应更新的模型预测控制器,引入纵横交叉优化算法实现优化求解,最大程度避免了求解陷入局部最优的情况,提高了张力控制系统的动态性能.通过仿真和实验分析,验证了所设计的张力协同控制系统具有良好的动态性能和鲁棒性.展开更多
This paper presents a closed-loop vector control structure based on adaptive Fuzzy Logic Sliding Mode Controller (FL-SMC) for a grid-connected Wave Energy Conversion System (WECS) driven Self-Excited Induction Generat...This paper presents a closed-loop vector control structure based on adaptive Fuzzy Logic Sliding Mode Controller (FL-SMC) for a grid-connected Wave Energy Conversion System (WECS) driven Self-Excited Induction Generator (SEIG). The aim of the developed control method is to automatically tune and optimize the scaling factors and the membership functions of the Fuzzy Logic Controllers (FLC) using Multi-Objective Genetic Algorithms (MOGA) and Multi-Objective Particle Swarm Optimization (MOPSO). Two Pulse Width Modulated voltage source PWM converters with a carrier-based Sinusoidal PWM modulation for both Generator- and Grid-side converters have been connected back to back between the generator terminals and utility grid via common DC link. The indirect vector control scheme is implemented to maintain balance between generated power and power supplied to the grid and maintain the terminal voltage of the generator and the DC bus voltage constant for variable rotor speed and load. Simulation study has been carried out using the MATLAB/Simulink environment to verify the robustness of the power electronics converters and the effectiveness of proposed control method under steady state and transient conditions and also machine parameters mismatches. The proposed control scheme has improved the voltage regulation and the transient performance of the wave energy scheme over a wide range of operating conditions.展开更多
This paper proposes a method of using multi controllers to control supermaneuverable aircraft. A nonlinear dynamic inversion controller is used for supermaneuver. A gain scheduled controller is used for routine man...This paper proposes a method of using multi controllers to control supermaneuverable aircraft. A nonlinear dynamic inversion controller is used for supermaneuver. A gain scheduled controller is used for routine maneuver. A switch algorithm is designed to switch the controllers. The flight envelopes of the controllers are different but have a common area in which the controllers are switched from one to the other. In the common area, some special boundaries are selected to decide switch conditions. The controllers all use vector thrust for lower velocity maneuver control. Unlike the variation structure theory to use a single boundary, this paper uses two boundaries for switching between the two controllers. One boundary is used for switching from dynamic inversion to gain scheduling, while the other is used for switching from gain scheduling to dynamic inversion. This can effectively avoid the system vibration caused by switching repeatedly at a single boundary. The method is very easy for engineering. It can reduce the risk of design of the supermaneuverable aircraft.展开更多
无刷直流电机作为家用电器和精密仪器的动力源器件,在实际控制系统中通常采用传统的比例-积分-微分(proportion integral differential,PID)控制,但传统的PID控制精准度较低,对外界干扰较为敏感,无法满足使用的精准要求。针对这一问题,...无刷直流电机作为家用电器和精密仪器的动力源器件,在实际控制系统中通常采用传统的比例-积分-微分(proportion integral differential,PID)控制,但传统的PID控制精准度较低,对外界干扰较为敏感,无法满足使用的精准要求。针对这一问题,一种利用粒子群算法来实现无刷直流电机矢量控制的方法被提出:首先,搭建无刷直流电机数学模型;其次,利用仿真软件对电机矢量控制系统模型进行搭建,再利用改进粒子群算法对电机PID控制器参数进行优化,以实现对无刷直流电机系统的精确控制;最后,以STM32F407单片机搭建实验平台,并进行实验验证。结果表明:该方法与传统矢量控制相比,在稳态为800 r/min和1500 r/min时输出的最大超调量分别降低了32.30%和38.09%,调整时间分别优化了15.25%和5.66%;在负载阶段的最大转速差缩减了29.28 r/min,调整时间优化了8.08%,抗干扰能力和系统稳定性显著提高。展开更多
基金Supported by the National Natural Science Foundation of China(21076179)the National Basic Research Program of China(2012CB720500)
文摘This paper presents a nonlinear model predictive control(NMPC) approach based on support vector machine(SVM) and genetic algorithm(GA) for multiple-input multiple-output(MIMO) nonlinear systems.Individual SVM is used to approximate each output of the controlled plant Then the model is used in MPC control scheme to predict the outputs of the controlled plant.The optimal control sequence is calculated using GA with elite preserve strategy.Simulation results of a typical MIMO nonlinear system show that this method has a good ability of set points tracking and disturbance rejection.
文摘三电机卷绕系统是一个强耦合非线性时变系统,存在卷轴半径、转动惯量以及摩擦系数等时变参数,导致张力协同控制精度较低.为了提高卷绕系统模型准确度,实时优化张力协同控制系统的动态性能,提出一种基于改进鲸鱼算法优化的多核最小二乘支持向量机回归(multi-kernel least squares support vector regression prediction model based on an improved whale algorithm optimization,WOA-M-LSSVR)预测模型和基于纵横交叉优化算法(crisscross optimization algorithm,CSO)优化的模型预测张力协同控制系统.根据最小二乘支持向量机回归原理建立多核LSSVR回归模型,并使用改进的自适应鲸鱼算法进行离线优化,得到系统预测模型;根据建立的预测模型,构建自适应更新的模型预测控制器,引入纵横交叉优化算法实现优化求解,最大程度避免了求解陷入局部最优的情况,提高了张力控制系统的动态性能.通过仿真和实验分析,验证了所设计的张力协同控制系统具有良好的动态性能和鲁棒性.
文摘This paper presents a closed-loop vector control structure based on adaptive Fuzzy Logic Sliding Mode Controller (FL-SMC) for a grid-connected Wave Energy Conversion System (WECS) driven Self-Excited Induction Generator (SEIG). The aim of the developed control method is to automatically tune and optimize the scaling factors and the membership functions of the Fuzzy Logic Controllers (FLC) using Multi-Objective Genetic Algorithms (MOGA) and Multi-Objective Particle Swarm Optimization (MOPSO). Two Pulse Width Modulated voltage source PWM converters with a carrier-based Sinusoidal PWM modulation for both Generator- and Grid-side converters have been connected back to back between the generator terminals and utility grid via common DC link. The indirect vector control scheme is implemented to maintain balance between generated power and power supplied to the grid and maintain the terminal voltage of the generator and the DC bus voltage constant for variable rotor speed and load. Simulation study has been carried out using the MATLAB/Simulink environment to verify the robustness of the power electronics converters and the effectiveness of proposed control method under steady state and transient conditions and also machine parameters mismatches. The proposed control scheme has improved the voltage regulation and the transient performance of the wave energy scheme over a wide range of operating conditions.
文摘This paper proposes a method of using multi controllers to control supermaneuverable aircraft. A nonlinear dynamic inversion controller is used for supermaneuver. A gain scheduled controller is used for routine maneuver. A switch algorithm is designed to switch the controllers. The flight envelopes of the controllers are different but have a common area in which the controllers are switched from one to the other. In the common area, some special boundaries are selected to decide switch conditions. The controllers all use vector thrust for lower velocity maneuver control. Unlike the variation structure theory to use a single boundary, this paper uses two boundaries for switching between the two controllers. One boundary is used for switching from dynamic inversion to gain scheduling, while the other is used for switching from gain scheduling to dynamic inversion. This can effectively avoid the system vibration caused by switching repeatedly at a single boundary. The method is very easy for engineering. It can reduce the risk of design of the supermaneuverable aircraft.
