高速飞行器再入过程中,具有参数大范围快速时变、强非线性的特性,对控制器的控制品质和稳定性提出了更高的要求。本文通过最优Oustaloup数字算法框图化实现分数阶PI^(λ)D^(μ)(Fractional-order PID,FOPID)控制器,建立高速飞行器参数...高速飞行器再入过程中,具有参数大范围快速时变、强非线性的特性,对控制器的控制品质和稳定性提出了更高的要求。本文通过最优Oustaloup数字算法框图化实现分数阶PI^(λ)D^(μ)(Fractional-order PID,FOPID)控制器,建立高速飞行器参数时变的非线性模型,结合ITAE(Integrated Time and Absolute Error)指标利用遗传算法(Genetic Algorithm,GA)寻优整定分数阶PI^(λ)D^(μ)参数,然后针对选定的分数阶PI^(λ)D^(μ)控制器,利用D-分解法分析高速飞行器的马赫数及攻角稳定区域。最后结合跟踪微分器设计了改进的分数阶PI^(λ)D^(μ)控制器。仿真结果表明,分数阶PI^(λ)D^(μ)控制器在具有更好的控制品质的同时可以在大范围内实现高速飞行器的稳定飞行。展开更多
A thermodynamics analysis on the leaching process of selenium residue and discussion on the behaviors of aqueous ionic in the leaching process were carried out. Through thermodynamical calculation, the values of AG an...A thermodynamics analysis on the leaching process of selenium residue and discussion on the behaviors of aqueous ionic in the leaching process were carried out. Through thermodynamical calculation, the values of AG and relevant potential expressions were obtained. According to these thermodynamical data, the φ-pH diagrams of Se-H2O system at 298 and 373 K were obtained; Simultaneously, the φ-pH diagrams of SO2-H2O and SO2-Se-H2O systems were drawn at 298 K. With increasing the temperature, the stable regions of HSeO3, SeO2- and SeO2- in the φ-pH diagram of Se-H2O system become gradually large, but the limits of pH in the stable region become gradually small. The stability area of reduction precipitation in the SO2-Se-H2O system was finally determined. The results of oxidization leaching experiments of selenium residue indicate that when the mass ratio of selenium residue to sodium chlorate is 2, the concentration of sulfuric acid is 300 g/L and the residue is agitated for 3 h at leaching temperature of 80 ℃, the leaching rate of selenium could reach 97.76 %. The experimental results conform the calculated results by φ-pH diagram. The selenium reduction precipitation in oxidization-leaching solution was analyzed under the conditions of acidity of 150 g/L, the sodium sulphite concentration of 35 g/L at the reductive temperature of 23 ℃ for 120 min. And this demonstrates the thermodynamics analysis.展开更多
The novel quantitative assessment method using transmission line measurement was developed. A new style of stability criterion was suggested which is based on the line measurement. The stability indices for lines, cut...The novel quantitative assessment method using transmission line measurement was developed. A new style of stability criterion was suggested which is based on the line measurement. The stability indices for lines, cutsets and power system according to features of transient energy in the lines were given, which not only provide a reliable and accurate assessment of the transient stability of power system, but also can be used to assess the effect of lines and cutsets on the transient stability and identify the weak transmission segment. Examples were presented by simulation on the IEEE-39 buses test system.展开更多
In this paper, a new evaluation method of probabilistic TTC based on SVSR calculation is developed through a hierarchical simulation. A smooth technology based on the non-parametric kernel estimator is adapted to obta...In this paper, a new evaluation method of probabilistic TTC based on SVSR calculation is developed through a hierarchical simulation. A smooth technology based on the non-parametric kernel estimator is adapted to obtain the time-dependent probabilistic density function of the feeder-head load data. In order to describe possible operating change directions of the operating point, the original hyper-cone-like(HCL) model is constructed to consider the probabilistic distribution function(PDF) extracted from feeder-head load data to replace the simple Normal Distribution model and the uncertain generator outputs. To realize the fast TTC calculation of the current operating point in random conditions, a sub-hyper-cone-like(SHCL) model in full power injections space is proposed, which is a similarity transformation of the original one.展开更多
A method is proposed to chaotify a class of complex networks via impulsive control, when the orbits of the impulsive systems are confined in a bounded area. Based on computing the largest Lyapunov exponent, theoretica...A method is proposed to chaotify a class of complex networks via impulsive control, when the orbits of the impulsive systems are confined in a bounded area. Based on computing the largest Lyapunov exponent, theoretical results and algorithmic analysis are given in details. Finally, numerical simulations are presented to illustrate the effectiveness of the method.展开更多
文摘高速飞行器再入过程中,具有参数大范围快速时变、强非线性的特性,对控制器的控制品质和稳定性提出了更高的要求。本文通过最优Oustaloup数字算法框图化实现分数阶PI^(λ)D^(μ)(Fractional-order PID,FOPID)控制器,建立高速飞行器参数时变的非线性模型,结合ITAE(Integrated Time and Absolute Error)指标利用遗传算法(Genetic Algorithm,GA)寻优整定分数阶PI^(λ)D^(μ)参数,然后针对选定的分数阶PI^(λ)D^(μ)控制器,利用D-分解法分析高速飞行器的马赫数及攻角稳定区域。最后结合跟踪微分器设计了改进的分数阶PI^(λ)D^(μ)控制器。仿真结果表明,分数阶PI^(λ)D^(μ)控制器在具有更好的控制品质的同时可以在大范围内实现高速飞行器的稳定飞行。
基金Project(51072233) supported by the National Natural Science Foundation of China
文摘A thermodynamics analysis on the leaching process of selenium residue and discussion on the behaviors of aqueous ionic in the leaching process were carried out. Through thermodynamical calculation, the values of AG and relevant potential expressions were obtained. According to these thermodynamical data, the φ-pH diagrams of Se-H2O system at 298 and 373 K were obtained; Simultaneously, the φ-pH diagrams of SO2-H2O and SO2-Se-H2O systems were drawn at 298 K. With increasing the temperature, the stable regions of HSeO3, SeO2- and SeO2- in the φ-pH diagram of Se-H2O system become gradually large, but the limits of pH in the stable region become gradually small. The stability area of reduction precipitation in the SO2-Se-H2O system was finally determined. The results of oxidization leaching experiments of selenium residue indicate that when the mass ratio of selenium residue to sodium chlorate is 2, the concentration of sulfuric acid is 300 g/L and the residue is agitated for 3 h at leaching temperature of 80 ℃, the leaching rate of selenium could reach 97.76 %. The experimental results conform the calculated results by φ-pH diagram. The selenium reduction precipitation in oxidization-leaching solution was analyzed under the conditions of acidity of 150 g/L, the sodium sulphite concentration of 35 g/L at the reductive temperature of 23 ℃ for 120 min. And this demonstrates the thermodynamics analysis.
基金National Natural Science Foundation ofChina( No.5 99770 0 1)
文摘The novel quantitative assessment method using transmission line measurement was developed. A new style of stability criterion was suggested which is based on the line measurement. The stability indices for lines, cutsets and power system according to features of transient energy in the lines were given, which not only provide a reliable and accurate assessment of the transient stability of power system, but also can be used to assess the effect of lines and cutsets on the transient stability and identify the weak transmission segment. Examples were presented by simulation on the IEEE-39 buses test system.
基金supported the National Hi-Tech Research and Development Program of China(Grant No.2015AA050403)the National Natural Science Foundation of China(Grant Nos.51277128+7 种基金51407125&51361135704)Statement of Collaboration between University of VictoriaCanadaTianjin UniversityChinaand"131"Talent&Innovative Team of Tianjin CityFundamental and Perspective Project of State Grid Corporation of China-"Study on the Energy Internet Technology Framework"Science and Technology Project of State Grid Corporation of China(Grant No.5217L0150004)
文摘In this paper, a new evaluation method of probabilistic TTC based on SVSR calculation is developed through a hierarchical simulation. A smooth technology based on the non-parametric kernel estimator is adapted to obtain the time-dependent probabilistic density function of the feeder-head load data. In order to describe possible operating change directions of the operating point, the original hyper-cone-like(HCL) model is constructed to consider the probabilistic distribution function(PDF) extracted from feeder-head load data to replace the simple Normal Distribution model and the uncertain generator outputs. To realize the fast TTC calculation of the current operating point in random conditions, a sub-hyper-cone-like(SHCL) model in full power injections space is proposed, which is a similarity transformation of the original one.
基金supported by the National Natural Science Foundation of China under Grant No.60573005the Key Scientific Research Project for Colleges and Universities of Henan Province under Grant No.15A120022Doctor Scientific Research Fund of Zhengzhou University of Light Industry under Grant No.2014BSJJ047
文摘A method is proposed to chaotify a class of complex networks via impulsive control, when the orbits of the impulsive systems are confined in a bounded area. Based on computing the largest Lyapunov exponent, theoretical results and algorithmic analysis are given in details. Finally, numerical simulations are presented to illustrate the effectiveness of the method.
