Aiming at a class of nonlinear systems with multiple equilibrium points, we present a dual-mode model predictive control algorithm with extended terminal constraint set combined with control invariant set and gain sch...Aiming at a class of nonlinear systems with multiple equilibrium points, we present a dual-mode model predictive control algorithm with extended terminal constraint set combined with control invariant set and gain schedule. Local LQR control laws and the corresponding maximum control invariant sets can be designed for finite equilibrium points. It is guaranteed that control invariant sets are overlapped each other. The union of the control invariant sets is treated as the terminal constraint set of predictive control. The feasibility and stability of the novel dual-mode model predictive control are investigated with both variable and fixed horizon. Because of the introduction of extended terminal constrained set, the feasibility of optimization can be guaranteed with short prediction horizon. In this way, the size of the optimization problem is reduced so it is computationally efficient. Finally, a simulation example illustrating the algorithm is presented.展开更多
An improved model predictive control algorithm is proposed for Hammerstein-Wiener nonlinear systems.The proposed synthesis algorithm contains two parts:offline design the polytopic invariant sets,and online solve the ...An improved model predictive control algorithm is proposed for Hammerstein-Wiener nonlinear systems.The proposed synthesis algorithm contains two parts:offline design the polytopic invariant sets,and online solve the min-max optimization problem.The polytopic invariant set is adopted to replace the traditional ellipsoid invariant set.And the parameter-correlation nonlinear control law is designed to replace the traditional linear control law.Consequently,the terminal region is enlarged and the control effect is improved.Simulation and experiment are used to verify the validity of the wind tunnel flow field control algorithm.展开更多
针对容错模式下的统一电能质量调节器(Unified Power Quality Conditioner,UPQC),提出了一种五桥臂形式的新型拓扑结构,实现故障下的电能质量扰动综合补偿。在此基础上,对串联变流器和并联变流器进行统一建模,提出了一种基于有限集模型...针对容错模式下的统一电能质量调节器(Unified Power Quality Conditioner,UPQC),提出了一种五桥臂形式的新型拓扑结构,实现故障下的电能质量扰动综合补偿。在此基础上,对串联变流器和并联变流器进行统一建模,提出了一种基于有限集模型预测控制(Finite Control Set Model Predictive Control,FCS-MPC)的五桥臂UPQC控制策略。相比传统线性控制策略,所提算法构建了统一的预测模型以及整合优化的价值函数,实现串联变流器与并联变流器的协同控制,提高了两侧变流器的补偿精度、暂态性能以及响应速度,有效降低了控制算法的复杂度和参数调节难度,并具有较高的参数鲁棒性。仿真结果验证了所提算法的可行性和有效性。展开更多
为保证全直流风电系统安全并网运行,系统直流电压稳定控制至关重要。全直流风电系统直流电压稳定控制采用比例积分(PI)控制时,PI参数较多且整定繁琐复杂,在非正常运行工况下动态响应速度相对较慢,控制精度不够高。针对以上问题,文章提...为保证全直流风电系统安全并网运行,系统直流电压稳定控制至关重要。全直流风电系统直流电压稳定控制采用比例积分(PI)控制时,PI参数较多且整定繁琐复杂,在非正常运行工况下动态响应速度相对较慢,控制精度不够高。针对以上问题,文章提出一种基于有限控制集模型预测控制(Finite Control Set-Model Predictive Control,FCS-MPC)原理对系统换流器桥臂晶体管开关状态进行控制的系统直流电压稳定控制策略。该策略结合机侧整流器及并网逆变器的电流预测模型,以换流器输出电流为控制变量构造代价函数,以代价函数为优化目标,为避免计算时延导致的控制延时,引入延时补偿提高控制准确度,并引入权重系数实现多目标优化,通过遍历计算产生最优开关组合信号触发换流器。在Matlab/Simulink中建立全直流风电系统的仿真模型,在不同工况下,对所提策略与传统PI控制进行对比仿真分析,仿真结果有效验证了所提控制策略的静态性能及动态性能。展开更多
为提高统一电能质量调节器(unified power quality conditioner,UPQC)对电能质量扰动的补偿精度和响应速度,将有限状态模型预测控制(finite control set model predictive control,FCS?MPC)算法引入到电网侧和负载侧控制器中,通过对补...为提高统一电能质量调节器(unified power quality conditioner,UPQC)对电能质量扰动的补偿精度和响应速度,将有限状态模型预测控制(finite control set model predictive control,FCS?MPC)算法引入到电网侧和负载侧控制器中,通过对补偿量检测环节进行改进,构建预测模型,价值函数以及滚动优化方法,设计了一种基于FCS?MPC算法的UPQC电能质量扰动补偿策略,降低了算法的复杂度和参数调试的繁琐性,有效提高了控制算法的补偿精度和响应速度。该文应用MATLAB/Simulink仿真环境构建仿真模型与控制算法,分别针对电压暂降/暂升补偿、谐波补偿、非线性电流补偿、无功功率补偿、负序分量补偿进行了仿真分析,实验结果验证了所设计方法的正确性和可行性。展开更多
针对长时间充放电后锂电池模组之间荷电状态(state of charge,SOC)不一致的问题,传统集中式均衡电路存在均衡速度过低的缺陷,以对称式开关阵列、Boost变换器与LC准谐振电路作为均衡主电路,提出了一种基于连续集模型预测控制(continuous ...针对长时间充放电后锂电池模组之间荷电状态(state of charge,SOC)不一致的问题,传统集中式均衡电路存在均衡速度过低的缺陷,以对称式开关阵列、Boost变换器与LC准谐振电路作为均衡主电路,提出了一种基于连续集模型预测控制(continuous control set model predictive control,CCS-MPC)的均衡控制策略。首先,对均衡系统进行建模,构建离散状态空间方程;然后,根据状态方程设计多步模型预测算法,并以SOC预测值和参考值、变换器开关管当前输入和上一时刻输入之间的误差作为价值函数;最后,对价值函数进行二次规划,在线求解出一组控制最优解,并应用于均衡系统,通过动态调整占空比以控制均衡电流的大小。相较于单步预测,多步预测需要考虑被控量在多个周期内保持最优,可以保证在每个均衡周期内均衡器都能输出最优的均衡电流,有效防止均衡器失稳。仿真结果表明,所提模型预测算法实现了各电池组SOC一致,保证了均衡电流的稳定输出,相比常规PI算法缩短了17%的均衡时间。展开更多
基金Supported by National Natural Science Foundation of China （60504026, 60674041） and National High Technology Research and Development Program of China （863 Program）（2006AA04Z173）.
基金Supported by National Natural Science Foundation of P. R. China (60474051, 60534020)Development Program of Shanghai Science and Technology Department (04DZ11008)the Program for New Century Excellent Talents in Universities of P. R. China (NCET)
文摘Aiming at a class of nonlinear systems with multiple equilibrium points, we present a dual-mode model predictive control algorithm with extended terminal constraint set combined with control invariant set and gain schedule. Local LQR control laws and the corresponding maximum control invariant sets can be designed for finite equilibrium points. It is guaranteed that control invariant sets are overlapped each other. The union of the control invariant sets is treated as the terminal constraint set of predictive control. The feasibility and stability of the novel dual-mode model predictive control are investigated with both variable and fixed horizon. Because of the introduction of extended terminal constrained set, the feasibility of optimization can be guaranteed with short prediction horizon. In this way, the size of the optimization problem is reduced so it is computationally efficient. Finally, a simulation example illustrating the algorithm is presented.
基金Project(61074074)supported by the National Natural Science Foundation,ChinaProject(KT2012C01J0401)supported by the Group Innovation Fund,China
文摘An improved model predictive control algorithm is proposed for Hammerstein-Wiener nonlinear systems.The proposed synthesis algorithm contains two parts:offline design the polytopic invariant sets,and online solve the min-max optimization problem.The polytopic invariant set is adopted to replace the traditional ellipsoid invariant set.And the parameter-correlation nonlinear control law is designed to replace the traditional linear control law.Consequently,the terminal region is enlarged and the control effect is improved.Simulation and experiment are used to verify the validity of the wind tunnel flow field control algorithm.
文摘针对容错模式下的统一电能质量调节器(Unified Power Quality Conditioner,UPQC),提出了一种五桥臂形式的新型拓扑结构,实现故障下的电能质量扰动综合补偿。在此基础上,对串联变流器和并联变流器进行统一建模,提出了一种基于有限集模型预测控制(Finite Control Set Model Predictive Control,FCS-MPC)的五桥臂UPQC控制策略。相比传统线性控制策略,所提算法构建了统一的预测模型以及整合优化的价值函数,实现串联变流器与并联变流器的协同控制,提高了两侧变流器的补偿精度、暂态性能以及响应速度,有效降低了控制算法的复杂度和参数调节难度,并具有较高的参数鲁棒性。仿真结果验证了所提算法的可行性和有效性。
文摘为保证全直流风电系统安全并网运行,系统直流电压稳定控制至关重要。全直流风电系统直流电压稳定控制采用比例积分(PI)控制时,PI参数较多且整定繁琐复杂,在非正常运行工况下动态响应速度相对较慢,控制精度不够高。针对以上问题,文章提出一种基于有限控制集模型预测控制(Finite Control Set-Model Predictive Control,FCS-MPC)原理对系统换流器桥臂晶体管开关状态进行控制的系统直流电压稳定控制策略。该策略结合机侧整流器及并网逆变器的电流预测模型,以换流器输出电流为控制变量构造代价函数,以代价函数为优化目标,为避免计算时延导致的控制延时,引入延时补偿提高控制准确度,并引入权重系数实现多目标优化,通过遍历计算产生最优开关组合信号触发换流器。在Matlab/Simulink中建立全直流风电系统的仿真模型,在不同工况下,对所提策略与传统PI控制进行对比仿真分析,仿真结果有效验证了所提控制策略的静态性能及动态性能。
文摘为提高统一电能质量调节器(unified power quality conditioner,UPQC)对电能质量扰动的补偿精度和响应速度,将有限状态模型预测控制(finite control set model predictive control,FCS?MPC)算法引入到电网侧和负载侧控制器中,通过对补偿量检测环节进行改进,构建预测模型,价值函数以及滚动优化方法,设计了一种基于FCS?MPC算法的UPQC电能质量扰动补偿策略,降低了算法的复杂度和参数调试的繁琐性,有效提高了控制算法的补偿精度和响应速度。该文应用MATLAB/Simulink仿真环境构建仿真模型与控制算法,分别针对电压暂降/暂升补偿、谐波补偿、非线性电流补偿、无功功率补偿、负序分量补偿进行了仿真分析,实验结果验证了所设计方法的正确性和可行性。
文摘针对长时间充放电后锂电池模组之间荷电状态(state of charge,SOC)不一致的问题,传统集中式均衡电路存在均衡速度过低的缺陷,以对称式开关阵列、Boost变换器与LC准谐振电路作为均衡主电路,提出了一种基于连续集模型预测控制(continuous control set model predictive control,CCS-MPC)的均衡控制策略。首先,对均衡系统进行建模,构建离散状态空间方程;然后,根据状态方程设计多步模型预测算法,并以SOC预测值和参考值、变换器开关管当前输入和上一时刻输入之间的误差作为价值函数;最后,对价值函数进行二次规划,在线求解出一组控制最优解,并应用于均衡系统,通过动态调整占空比以控制均衡电流的大小。相较于单步预测,多步预测需要考虑被控量在多个周期内保持最优,可以保证在每个均衡周期内均衡器都能输出最优的均衡电流,有效防止均衡器失稳。仿真结果表明,所提模型预测算法实现了各电池组SOC一致,保证了均衡电流的稳定输出,相比常规PI算法缩短了17%的均衡时间。
