对于多变量系统,回路间的关联分析和变量配对是控制系统设计的第一步。文献针对稳态相对增益阵(relative gain array,RGA)只考虑了系统的稳态特性而没有考虑动态过程中各回路的影响的基础上提出了各种改进的动态相对增益阵。在多变量状...对于多变量系统,回路间的关联分析和变量配对是控制系统设计的第一步。文献针对稳态相对增益阵(relative gain array,RGA)只考虑了系统的稳态特性而没有考虑动态过程中各回路的影响的基础上提出了各种改进的动态相对增益阵。在多变量状态反馈预测控制(SFPC)的基础上提出了一种新的变量配对标准,能比较充分的反映控制过程的动态和稳态信息。通过对预测时域P的优化选择确定被控过程的相关性指数矩阵μ,并将μ与稳态信息阵K相结合得出最终的配对矩阵Λ。最后通过实例研究与其他配对方法比较,表明提出的方法能得出比较好的变量配对结果。展开更多
为解决电池储能系统(battery energy storage system,BESS)平抑风电波动过程中荷电状态(state of charge,SOC)和健康状态(state of health,SOH)一致性较低、电池寿命损耗较高的问题,该文提出了面向风电波动平抑基于考虑通讯时延的分布...为解决电池储能系统(battery energy storage system,BESS)平抑风电波动过程中荷电状态(state of charge,SOC)和健康状态(state of health,SOH)一致性较低、电池寿命损耗较高的问题,该文提出了面向风电波动平抑基于考虑通讯时延的分布一致性算法(distributed consistency algorithm considering communication delay,C−DCA)的BESS分组控制策略,该控制策略包括初级和次级2个功率分配过程。首先,利用改进旋转门(improved swing door trending,ISDT)算法获取BESS功率指令;然后,建立考虑BESS寿命损耗、SOC与SOH一致性、并网波动率与算法迭代速度的双电池组初级功率分配模型,结合BESS充/放电状态将功率指令顺序分配至电池组,实现初级功率分配;接着,将状态反馈预测控制(state feedback predictive control,SFPC)与输出变量动态反馈引入C−DCA,形成改进C−DCA,进一步设计基于SOC−SOH的权矩阵计算方法,并根据改进C−DCA的计算结果将功率指令从电池组分配给电池单元,完成次级功率分配;最后,电池单元响应各自功率指令。以某风电场实际出力进行仿真,并与其它多种方法进行对比。结果表明,该研究方法降低了风电并网波动率,提升了控制算法的鲁棒性,减少了算法占用内存,同时兼顾了电池单元SOC和SOH的一致性,更大程度上降低了BESS寿命损耗。展开更多
An adaptive state feedback predictive control （SFPC） scheme and an expert control scheme are presented and applied to the temperature control of a 1200 kt·a^-1 delayed coking furnace, which is the key equipment...An adaptive state feedback predictive control （SFPC） scheme and an expert control scheme are presented and applied to the temperature control of a 1200 kt·a^-1 delayed coking furnace, which is the key equipment for the delayed coking process. Adaptive SFPC is used to improve the performance of temperature control in normal operation. A simplified nonlinear model on the basis of first principles of the furnace is developed to obtain a state space model by linearization. Taking advantage of the nonlinear model, an online model adapting method is presented to accommodate the dynamic change of process characteristics because of tube coking and load changes. To compensate the large inverse response of outlet temperature resulting from the sudden increase of injected steam of a particular velocity to tubes, a monitoring method and an expert control scheme based on heat balance calculation are proposed. Industrial implementation shows the effectiveness and feasibility of the proposed control strategy.展开更多
In this article, state feedback predictive controller for hybrid system via parametric programming is proposed. First, mixed logic dynamic （MLD） modeling mechanism for hybrid system is analyzed, which has a distingu...In this article, state feedback predictive controller for hybrid system via parametric programming is proposed. First, mixed logic dynamic （MLD） modeling mechanism for hybrid system is analyzed, which has a distinguished advantage to deal with the logic rules and constraints of a plant. Model predictive control algorithm with moving horizon state estimator （MHE） is presented. The estimator is adopted to estimate the current state of the plant with process disturbance and measurement noise, and the state estimated are utilized in the predictive controller for both regulation and tracking problems of the hybrid system based on MLD model. Off-line parametric programming is adopted and then on-line mixed integer programming problem can be treated as the parameter programming with estimated state as the parameters. A three tank system is used for computer simulation, results show that the proposed MHE based predictive control via parametric programming is effective for hybrid system with model/olant mismatch, and has a potential for the engineering applications.展开更多
文摘对于多变量系统,回路间的关联分析和变量配对是控制系统设计的第一步。文献针对稳态相对增益阵(relative gain array,RGA)只考虑了系统的稳态特性而没有考虑动态过程中各回路的影响的基础上提出了各种改进的动态相对增益阵。在多变量状态反馈预测控制(SFPC)的基础上提出了一种新的变量配对标准,能比较充分的反映控制过程的动态和稳态信息。通过对预测时域P的优化选择确定被控过程的相关性指数矩阵μ,并将μ与稳态信息阵K相结合得出最终的配对矩阵Λ。最后通过实例研究与其他配对方法比较,表明提出的方法能得出比较好的变量配对结果。
文摘为解决电池储能系统(battery energy storage system,BESS)平抑风电波动过程中荷电状态(state of charge,SOC)和健康状态(state of health,SOH)一致性较低、电池寿命损耗较高的问题,该文提出了面向风电波动平抑基于考虑通讯时延的分布一致性算法(distributed consistency algorithm considering communication delay,C−DCA)的BESS分组控制策略,该控制策略包括初级和次级2个功率分配过程。首先,利用改进旋转门(improved swing door trending,ISDT)算法获取BESS功率指令;然后,建立考虑BESS寿命损耗、SOC与SOH一致性、并网波动率与算法迭代速度的双电池组初级功率分配模型,结合BESS充/放电状态将功率指令顺序分配至电池组,实现初级功率分配;接着,将状态反馈预测控制(state feedback predictive control,SFPC)与输出变量动态反馈引入C−DCA,形成改进C−DCA,进一步设计基于SOC−SOH的权矩阵计算方法,并根据改进C−DCA的计算结果将功率指令从电池组分配给电池单元,完成次级功率分配;最后,电池单元响应各自功率指令。以某风电场实际出力进行仿真,并与其它多种方法进行对比。结果表明,该研究方法降低了风电并网波动率,提升了控制算法的鲁棒性,减少了算法占用内存,同时兼顾了电池单元SOC和SOH的一致性,更大程度上降低了BESS寿命损耗。
基金the State Key Development Program for Basic Research of China(2002CB312200)the National High Technology Research and Development Program of China(2007AA04Z193)
文摘An adaptive state feedback predictive control （SFPC） scheme and an expert control scheme are presented and applied to the temperature control of a 1200 kt·a^-1 delayed coking furnace, which is the key equipment for the delayed coking process. Adaptive SFPC is used to improve the performance of temperature control in normal operation. A simplified nonlinear model on the basis of first principles of the furnace is developed to obtain a state space model by linearization. Taking advantage of the nonlinear model, an online model adapting method is presented to accommodate the dynamic change of process characteristics because of tube coking and load changes. To compensate the large inverse response of outlet temperature resulting from the sudden increase of injected steam of a particular velocity to tubes, a monitoring method and an expert control scheme based on heat balance calculation are proposed. Industrial implementation shows the effectiveness and feasibility of the proposed control strategy.
文摘In this article, state feedback predictive controller for hybrid system via parametric programming is proposed. First, mixed logic dynamic （MLD） modeling mechanism for hybrid system is analyzed, which has a distinguished advantage to deal with the logic rules and constraints of a plant. Model predictive control algorithm with moving horizon state estimator （MHE） is presented. The estimator is adopted to estimate the current state of the plant with process disturbance and measurement noise, and the state estimated are utilized in the predictive controller for both regulation and tracking problems of the hybrid system based on MLD model. Off-line parametric programming is adopted and then on-line mixed integer programming problem can be treated as the parameter programming with estimated state as the parameters. A three tank system is used for computer simulation, results show that the proposed MHE based predictive control via parametric programming is effective for hybrid system with model/olant mismatch, and has a potential for the engineering applications.
