检索结果-南通市图书馆

Dynamic optimization of 1,3-propanediol fermentation process:A switched dynamical system approach

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2022年第4期35卷 192-204页

作者： Xiang Wu Yuzhou Hou kanjian zhang Ming Cheng School of Mathematical Sciences Guizhou Normal UniversityGuiyang 550001China School of Life Sciences Guizhou Normal UniversityGuiyang 550001China School of Electrical Engineering Southeast UniversityNanjing 210096China School of Automation Southeast UniversityNanjing 210096China Key Laboratory of Measurement and Control of CSE Ministry of EducationSoutheast UniversityNanjing 210096China

This paper considers a dynamic optimization problem(DOP)of 1,3-propanediol fermentation process(1,3-PFP).Our main contributions are as ***,the DOP of 1,3-PFP is modeled as an optimal control problem of switched dynamical *** the existing switched dynamical system optimal control problem,the state-dependent switching method is applied to design the switching ***,in order to obtain the numerical solution,by introducing a discrete-valued function and using a relaxation technique,this problem is transformed into a nonlinear parameter optimization problem(NPOP).Although the gradient-based algorithm is very efficient for solving NPOPs,the existing algorithm is always trapped in a local minimum for such problems with multiple local ***,in order to overcome this challenge,a gradient-based random search algorithm(GRSA)is proposed based on an improved gradient-based algorithm(IGA)and a novel random search algorithm(NRSA),which cannot usually be trapped in a local *** convergence results are also established,and show that the GRSA is globally ***,a DOP of 1,3-PFP is provided to illustrate the effectiveness of the GRSA proposed by this paper.

关键词： Process control Optimization Mathematical modeling Switched system State-dependent switching Global optimization

Inter-hour direct normal irradiance forecast with multiple data types and time-series

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2019年第5期7卷 1319-1327页

作者： Tingting ZHU Hai ZHOU Haikun WEI Xin ZHAO kanjian zhang Jinxia zhang Key Laboratory of Measurement and Control of CSE Ministry of EducationSchool of AutomationSoutheast UniversityNanjing 210096China State Key Laboratory of Operation and Control of Renewable Energy and Storage Systems(China Electric Power Research Institute) Nanjing 210003China

Boosted by a strong solar power market,the electricity grid is exposed to risk under an increasing share of fluctuant solar *** increase the stability of the electricity grid,an accurate solar power forecast is needed to evaluate such *** terms of forecast,solar irradiance is the key factor of solar power generation,which is affected by atmospheric conditions,including surface meteorological variables and column integrated *** variables involve multiple numerical timeseries and ***,few studies have focused on the processing method of multiple data types in an interhour direct normal irradiance(DNI)*** this study,a framework for predicting the DNI for a 10-min time horizon was developed,which included the nondimensionalization of multiple data types and time-series,development of a forecast model,and transformation of the *** atmospheric variables were considered in the forecast framework,including the historical DNI,wind speed and direction,relative humidity time-series,and ground-based cloud *** were conducted to evaluate the performance of the forecast *** experimental results demonstrate that the proposed method performs well with a normalized mean bias error of 0.41%and a normalized root mean square error(n RMSE)of20.53%,and outperforms the persistent model with an improvement of 34%in the nRMSE.

关键词： Inter-hour forecast Direct normal irradiance Ground-based cloud images Multiple data types Multiple time-series

A gradient-based stochastic search approach for optimal harvesting strategy in shrimp culture 36

在线全文

学校读者我要写书评

暂无评论

A gradient-based stochastic search approach for optimal harv...

第36届中国控制会议

作者： Wu Xiang Liu Qiaodan Lei Bangjun zhang kanjian School of Mathematical Sciences Guizhou Normal University School of Electrical Engineering Southeast University School of Electrical and Information Engineering Guizhou Institute of Technology School of Automation Southeast University

ISBN: (纸本)9781538629185

This paper considers an optimal harvesting strategy problem arising in shrimp culture. The problem is formulated as an optimal control problem of nonlinear impulsive system. Since the impulsive switching constraints is very complex, the impulsive switching instants are unknown, and the objective function is not continuously differentiable, it is difficult to solve this problem by standard optimization methods. To overcome the difficulty, by introducing a novel binary variable for each sale price of shrimp, relaxing the binary variable, and imposing a penalty function on the relaxation term, the nonlinear impulsive system optimal control problem is transformed into a parameter optimization problem, which can be solved efficiently using any gradient-based optimization technique. Then, a gradient-based stochastic search approach is proposed for solving this ***, a harvesting strategy problem is presented to illustrate the efficiency of the approach proposed.

关键词： Optimal control Nonlinear impulsive system Binary novel variable Penalty function Shrimp culture

Sensitivity Analysis of Optimal Control Problems for Switched Systems

在线全文

cnki会议

学校读者我要写书评

暂无评论

Sensitivity Analysis of Optimal Control Problems for Switche...

第26届中国控制与决策会议

作者： Jinjin Liu kanjian zhang Xiaomei Liu Haikun Wei School of Automation Southeast University Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of EducationSoutheast University

ISBN: (纸本)9781479937097

This paper investigates the problem of sensitivity analysis for switched autonomous systems involving uncertain parameters. The aim is to find switching instants which minimizes the cost function, and meanwhile makes it robust to the variation of the original objective with respect to unknown parameters. We focus on the fixed switching mode sequences and convert the sensitivity problem into a conventional optimal switched control problem, which can be solved directly using the gradient descent algorithm. The efficacy of the proposed method is illustrated via numerical example.

关键词： Switched systems Sensitivity analysis Optimal control Parameter variation

Genetic Algorithm-based Location and Control Strategy of Grid-connected BESS

在线全文

cnki会议

学校读者我要写书评

暂无评论

Genetic Algorithm-based Location and Control Strategy of Gri...

第40届中国控制会议

作者： Jilong Zhuang Jian Ge kanjian zhang Haikun Wei Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of Education School of AutomationSoutheast University

With the development of energy storage technology, more and more battery energy storage stations（BESSs） are connected to the power grid to restrain fluctuation and intermittency of renewable energy generation on the stability of the power grid. However, the connection with BESS will change the topology and power flow direction of the power grid. Therefore, based on the actual geographical wiring diagram and related data, this paper describes a grid model to analyze the influence of BESS connected to the power grid on power flow and node voltage. When the voltage of each node is stable, the genetic algorithm is applied to study how to select the access position and control the power of centralized or distributed BESSs to minimize the active power loss of the power grid. It provides guidance and reference for future location planning and control strategy of BESSs in the power grid.

关键词： Battery Energy Storage Station Power Flow Calculation Optimization

A Classification Method of Photovoltaic Modules Shaded Area Based on Weighted K-nn

在线全文

cnki会议

学校读者我要写书评

暂无评论

A Classification Method of Photovoltaic Modules Shaded Area ...

第40届中国控制会议

作者： Lin Xia Chenxi Li kanjian zhang Haikun Wei Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of EducationSchool of AutomationSoutheast University

In the actual operation of photovoltaic power stations,various types of shading,including leaves,bird’s droppings,and clouds,will inevitably *** shadings will affect the output power of the *** them,if a small area of shading is not removed in time,hot spots may be formed,accelerating the aging of photovoltaic modules,and not conducive to the healthy and stable operation of the overall ***,different shading objects cover different shading areas of photovoltaic modules,which cause different *** paper mainly analyzes the influence of different areas of shading on the current-voltage curve of photovoltaic modules,and proposes a classification algorithm based on weighted K-nn to classify the shading area according to the current-voltage curve characteristics of the module,which is helpful for subsequent identification of shading types and troubleshooting.

关键词： Photovoltaic Modules Shading Area K-Nearest Neighbor Classification

Stability analysis of time-varying systems via parameter-dependent homogeneous Lyapunov functions

在线全文

cnki会议

学校读者我要写书评

暂无评论

Journal of Southeast University(English Edition) 2014年第3期30卷 302-305页

作者：张化生张侃健东南大学复杂工程系统测量与控制教育部重点实验室南京210096 东南大学自动化学院南京210096 聊城大学数学科学学院聊城252000

This paper considers the stability analysis of linear continuous-time systems, and that the dynamic matrices are affected by uncertain time-varying parameters, which are assumed to be bounded, continuously differentiable, with bounded rates of variation. First, sufficient conditions of stability for time-varying systems are given by the commonly used parameter-dependent quadratic Lyapunov function. Moreover, the use of homogeneous polynomial Lyapunov functions for the stability analysis of the linear system subject to the time-varying parametric uncertainty is introduced. Sufficient conditions to determine the sought after Lyapunov function is derived via a suitable paramenterization of polynomial homogeneous forms. A numerical example is given to illustrate that the stability conditions are less conservative than similar tests in the literature.

关键词： linear time-varying systems polytopic uncertainty robust stability linear matrix inequality

在线全文

学校读者我要写书评

暂无评论

基于符号跟随系统的无源控制设计

东南大学学报（自然科学版） 2007年第4期37卷 610-613页

作者：张侃健冯纯伯东南大学自动化研究所南京210096

研究了基于符号跟随系统(SFS)的无源控制设计问题,讨论了该控制方案的适用范围.通过构造出的一个反例,说明了并联一般的无源系统后SFS无法保证实现系统的无源化.进一步分析了引入SFS后的单位负反馈可能导致闭环系统病态的问题,由此给出... 详细信息

研究了基于符号跟随系统(SFS)的无源控制设计问题,讨论了该控制方案的适用范围.通过构造出的一个反例,说明了并联一般的无源系统后SFS无法保证实现系统的无源化.进一步分析了引入SFS后的单位负反馈可能导致闭环系统病态的问题,由此给出了在反馈通道中引入严格真无源系统的控制方案,得到了基于无源系统理论的输出反馈控制,并作了相应的特性分析.仿真以非最小相位系统为例,所得结果表明了该控制方案的有效性.SFS的引入拓宽了经典控制方案中参数的可调范围,可以较好地改善闭环系统的动态性能.

关键词：无源性逻辑切换符号跟随病态系统

A Tree-based Clear Sky Model for DNI Forecasting

在线全文

学校读者我要写书评

暂无评论

A Tree-based Clear Sky Model for DNI Forecasting

第30届中国控制与决策会议

作者： Yu Shen Haikun Wei Xin Zhao Tingting Zhu kanjian zhang Key Laboratory of Measurement and Control of CSE Ministry of EducationSchool of Automation Southeast University

Solar irradiance is a renewable energy that has been utilized by power plants. Direct normal irradiance（DNI）forecasting is a crucial approach to reduce the output uncertainty of solar power plants, and enhance reliability of power grids. According to statistics, the solar radiation of clear sky accounts for more than half of the total amount of radiation in a year. Hence, clear sky DNI forecasting models play a significant role in solar power systems. The existing clear sky models assume that the atmosphere is at rest and ignore the variation of aerosol optical depth in a day, which may reduce the accuracy of DNI forecasting. In this paper, a novel tree-based piecewise clear sky model is proposed to capture aerosol extinction coefficient varying with time in a day and forecast DNI when clouds are absent. Firstly, a linear model is deduced from a physical equation to represent the relationship of air mass and DNI approximately. Then, model trees with this linear mode at each leaf node are create. The database of the National Renewable Energy Laboratory（NREL）is used for experiments to evaluate the performance of the proposed model, compared with other clear sky models. The results of the experiments show that the proposed model provides more accurate forecast of DNI than other clear sky models.

关键词： Direct Normal Irradiance Clear Sky Model Model Tree Piecewise Linear Model