主动队列管理(active queue management,简称AQM)是网络拥塞控制的研究热点之一,其中的关键问题是如何设计反馈控制策略.提出一种新的基于D稳定域和时间乘以误差绝对值乘积积分(integral of time-weighted absolute error,简称ITAE)性...主动队列管理(active queue management,简称AQM)是网络拥塞控制的研究热点之一,其中的关键问题是如何设计反馈控制策略.提出一种新的基于D稳定域和时间乘以误差绝对值乘积积分(integral of time-weighted absolute error,简称ITAE)性能准则的比例-积分-微分(proportional-integral-differential,简称PID)优化设计方法(简称DITAE-PID),并用于AQM控制器的设计,控制闭环系统的理想动态性能.首先在复平面上设定一组理想的D稳定域,然后以ITAE为目标函数,通过数值优化算法求出控制器的参数,使得闭环系统的所有特征根都在D稳定域内,以降低排队延时,提高有效吞吐量.对比仿真实验结果表明,该算法能够预先探测和控制拥塞,有较好的鲁棒性,链路利用率更高,丢包率更小,平均队列长度更趋于期望值,同时,趋于期望队列长度的时间更短,其综合性能明显优于典型的随机早期探测(random early detection,简称RED)和比例-积分(proportional-integral,简称PI)算法.展开更多
采用α阶逆系统理论对五自由度磁轴承系统进行解耦控制.在建立磁轴承系统状态方程的基础上,对该系统进行了基于逆系统理论的线性解耦,并根据时间乘以误差绝对值积分(integral of time-weighted absolute error,ITAE)最小评价准则设计了...采用α阶逆系统理论对五自由度磁轴承系统进行解耦控制.在建立磁轴承系统状态方程的基础上,对该系统进行了基于逆系统理论的线性解耦,并根据时间乘以误差绝对值积分(integral of time-weighted absolute error,ITAE)最小评价准则设计了闭环控制器.仿真和试验表明,α阶逆系统解耦后系统各自由度之间不存在耦合,解耦控制器与PID控制器相比,具有更好的动态特性和静态特性.展开更多
An IMC-PID controller was proposed for unstable second-order time delay system which shows the characteristics of inverse response(RHP zero). A plot of Ms versus λ was suggested to calculate the suitable tuning param...An IMC-PID controller was proposed for unstable second-order time delay system which shows the characteristics of inverse response(RHP zero). A plot of Ms versus λ was suggested to calculate the suitable tuning parameter λ, which provides a trade-off between performance and robustness. Six different forms of process models were selected from literature to show the applicability of the present method. Performance of controller was calculated by ITAE and total variation TV and compared with recently published tuning rules. Undesirable overshoot was removed by using a set-point weighting parameter. Robustness was tested by introducing a perturbation into the various model parameters and closed-loop results show that the designed controller is robust in the case of model uncertainty. The proposed method shows an overall better closed-loop response as compared to other recently reported methods.展开更多
This paper presents an approach for oscillation damping with an integrated multi-stage linear quadratic regulator(MSLQR)FACTS controller combining power oscillation damping(POD)capabilities.The particle swarm optimiz...This paper presents an approach for oscillation damping with an integrated multi-stage linear quadratic regulator(MSLQR)FACTS controller combining power oscillation damping(POD)capabilities.The particle swarm optimization(PSO)technique has been used for precise tuning initial control parameters of power system stabilizers(PSS)and FACTS devices(such as STATCOM and UPFC)which results in improved controller performance.It is observed that the proposed control structure damps the oscillations adequately and is modular in design methodology.The sample power system comprising six areas is considered to demonstrate the effectiveness of the proposed concept.The states inter-relation which is shown with eigenvalues reflects better regulation with the proposed controller.The step response also validates the controller performance.展开更多
Aiming at the problems of slow dynamic response and weak robustness of integer-order proportional integral(PI)controller in double closed loop vector control system of permanent magnet synchronous motor(PMSM),a method...Aiming at the problems of slow dynamic response and weak robustness of integer-order proportional integral(PI)controller in double closed loop vector control system of permanent magnet synchronous motor(PMSM),a method of combining dragonfly algorithm with fractional order PI control is proposed for off-line parameter tuning for the outer loop of speed of the system.The parameter to be optimized is used as the spatial position of the optimal individual searching for food sources in the search space,and the error performance index integrated time and absolute error(ITAE)is used as its target fitness function.The motor speed regulation performances of traditional engineering experience setting integer order PI,particle swarm optimization algorithm tuning fractional order PI and dragonfly algorithm tuning fractional order PI are compared,respectively.Results show that the fractional order PI controller optimized by dragonfly algorithm can improve the dynamic response performance of the system,reduce overshoot and enhance robustness,which proves the feasibility and superiority of the optimization strategy.展开更多
In this paper, a new analysis and design method for proportional-integrative-derivative （PID） tuning is proposed based on controller scaling analysis. Integral of time absolute error （ITAE） index is minimized for ...In this paper, a new analysis and design method for proportional-integrative-derivative （PID） tuning is proposed based on controller scaling analysis. Integral of time absolute error （ITAE） index is minimized for specified gain and phase margins （GPM） constraints, so that the transient performance and robustness are both satisfied. The requirements on gain and phase margins are ingeniously formulated by real part constraints （RPC） and imaginary part constraints （IPC）. This set of new constraints is simply related with three parameters and decoupling of the remaining four unknowns, including three controller parameters and the gain margin, in the nonlinear and coupled characteristic equation simultaneously. The formulas of the optimal GPM-PID are derived based on controller scaling analysis. Finally, this method is applied to liquid level control of coke fractionation tower, which demonstrate that the proposed method provides better disturbance rejection and robust tracking performance than some commonly used PID tuning methods.展开更多
基金Supposed by the National Natural Science Foundation of China under Grant No.60373053(国家自然科学基金)the National High-Tech Research and Development Plan of China under Grant Nos.2004AA1Z2100+3 种基金2005AA113140(国家高技术研究发展计划(863))the State Education Ministry Scientific Research Foundation for the Returned Overseas Chinese Scholars under Grant No.[2003]406(国家教育部留学回国人员科研启动基金)the One-Hundred-Talent Program of the Chinese Academy of Sciences(中国科学院"百人计划")the Chinese Academy of Sciences and Royal Society of United Kingdom for the Joint Research Project under Grant No.20030389(中国科学院与英国皇家学会国际合作项目)
文摘主动队列管理(active queue management,简称AQM)是网络拥塞控制的研究热点之一,其中的关键问题是如何设计反馈控制策略.提出一种新的基于D稳定域和时间乘以误差绝对值乘积积分(integral of time-weighted absolute error,简称ITAE)性能准则的比例-积分-微分(proportional-integral-differential,简称PID)优化设计方法(简称DITAE-PID),并用于AQM控制器的设计,控制闭环系统的理想动态性能.首先在复平面上设定一组理想的D稳定域,然后以ITAE为目标函数,通过数值优化算法求出控制器的参数,使得闭环系统的所有特征根都在D稳定域内,以降低排队延时,提高有效吞吐量.对比仿真实验结果表明,该算法能够预先探测和控制拥塞,有较好的鲁棒性,链路利用率更高,丢包率更小,平均队列长度更趋于期望值,同时,趋于期望队列长度的时间更短,其综合性能明显优于典型的随机早期探测(random early detection,简称RED)和比例-积分(proportional-integral,简称PI)算法.
文摘采用α阶逆系统理论对五自由度磁轴承系统进行解耦控制.在建立磁轴承系统状态方程的基础上,对该系统进行了基于逆系统理论的线性解耦,并根据时间乘以误差绝对值积分(integral of time-weighted absolute error,ITAE)最小评价准则设计了闭环控制器.仿真和试验表明,α阶逆系统解耦后系统各自由度之间不存在耦合,解耦控制器与PID控制器相比,具有更好的动态特性和静态特性.
基金India (MHRD, India) for providing financial support
文摘An IMC-PID controller was proposed for unstable second-order time delay system which shows the characteristics of inverse response(RHP zero). A plot of Ms versus λ was suggested to calculate the suitable tuning parameter λ, which provides a trade-off between performance and robustness. Six different forms of process models were selected from literature to show the applicability of the present method. Performance of controller was calculated by ITAE and total variation TV and compared with recently published tuning rules. Undesirable overshoot was removed by using a set-point weighting parameter. Robustness was tested by introducing a perturbation into the various model parameters and closed-loop results show that the designed controller is robust in the case of model uncertainty. The proposed method shows an overall better closed-loop response as compared to other recently reported methods.
文摘This paper presents an approach for oscillation damping with an integrated multi-stage linear quadratic regulator(MSLQR)FACTS controller combining power oscillation damping(POD)capabilities.The particle swarm optimization(PSO)technique has been used for precise tuning initial control parameters of power system stabilizers(PSS)and FACTS devices(such as STATCOM and UPFC)which results in improved controller performance.It is observed that the proposed control structure damps the oscillations adequately and is modular in design methodology.The sample power system comprising six areas is considered to demonstrate the effectiveness of the proposed concept.The states inter-relation which is shown with eigenvalues reflects better regulation with the proposed controller.The step response also validates the controller performance.
基金Supported by the National Natural Science Foundation of China(61603242)。
文摘Aiming at the problems of slow dynamic response and weak robustness of integer-order proportional integral(PI)controller in double closed loop vector control system of permanent magnet synchronous motor(PMSM),a method of combining dragonfly algorithm with fractional order PI control is proposed for off-line parameter tuning for the outer loop of speed of the system.The parameter to be optimized is used as the spatial position of the optimal individual searching for food sources in the search space,and the error performance index integrated time and absolute error(ITAE)is used as its target fitness function.The motor speed regulation performances of traditional engineering experience setting integer order PI,particle swarm optimization algorithm tuning fractional order PI and dragonfly algorithm tuning fractional order PI are compared,respectively.Results show that the fractional order PI controller optimized by dragonfly algorithm can improve the dynamic response performance of the system,reduce overshoot and enhance robustness,which proves the feasibility and superiority of the optimization strategy.
基金supported by National Natural Science Foundation of China(Nos.61403149 and 61273069)Natural Science Foundation of Fujian Province(No.2015J01261)the Scientific Research Foundation of National Huaqiao University
文摘In this paper, a new analysis and design method for proportional-integrative-derivative （PID） tuning is proposed based on controller scaling analysis. Integral of time absolute error （ITAE） index is minimized for specified gain and phase margins （GPM） constraints, so that the transient performance and robustness are both satisfied. The requirements on gain and phase margins are ingeniously formulated by real part constraints （RPC） and imaginary part constraints （IPC）. This set of new constraints is simply related with three parameters and decoupling of the remaining four unknowns, including three controller parameters and the gain margin, in the nonlinear and coupled characteristic equation simultaneously. The formulas of the optimal GPM-PID are derived based on controller scaling analysis. Finally, this method is applied to liquid level control of coke fractionation tower, which demonstrate that the proposed method provides better disturbance rejection and robust tracking performance than some commonly used PID tuning methods.
