由于可再生能源和负荷的不确定性,电力系统潮流分析需要有效的工具。目前的多数研究都假设一组给定的概率密度函数(PDF:Probability Density Functions)建模不确定性,并开发参数概率潮流工具。为此,提出了一种非参数概率潮流分析方法确...由于可再生能源和负荷的不确定性,电力系统潮流分析需要有效的工具。目前的多数研究都假设一组给定的概率密度函数(PDF:Probability Density Functions)建模不确定性,并开发参数概率潮流工具。为此,提出了一种非参数概率潮流分析方法确定潮流输出的偏微分方程。该方法基于平均值一阶鞍点近似。对于n个随机变量系统,利用潮流计算建立一阶Taylor级数展开,然后采用鞍点近似确定期望输出变量的概率特性。所提出的非参数估计器在需要合理的计算量的同时,能提供精确的结果。此外,在不使用积分或微分算子的情况下,直接建立了潮流输出的概率分布函数和累积分布函数。在IEEE 14总线和IEEE 118总线测试系统上进行了测试,所得结果与其他方法相比,MVFOSPA(Mean Value First Order Saddle Point Approximation)比MCS(Monte Carlo Simulation)算法运行时间减少了12%,验证了MVFOSPA方法的有效性。展开更多
We derive an exact solution for a spherically symmetric Bardeen black hole surrounded by perfect fluid dark matter(PFDM).By treating the magnetic charge g and dark matter parameter a as thermodynamic variables,we find...We derive an exact solution for a spherically symmetric Bardeen black hole surrounded by perfect fluid dark matter(PFDM).By treating the magnetic charge g and dark matter parameter a as thermodynamic variables,we find that the first law of thermodynamics and the corresponding Smarr formula are satisfied.The thermodynamic stability of the black hole is also studied.The results show that there exists a critical radius r+C where the heat capacity diverges,suggesting that the black hole is thermodynamically stable in the range 0 <r+<r+C. In addition,the critical radius r+C increases with the magnetic charge g and decreases with the dark matter parameter a.Applying the Newman-Janis algorithm,we generalize the spherically symmetric solution to the corresponding rotating black hole.With the metric at hand,the horizons and ergospheres are studied.It turns out that for a fixed dark matter parameter a,in a certain range,with the increase of the rotation parameter a and magnetic charge g,the Cauchy horizon radius increases while the event horizon radius decreases.Finally,we investigate the energy extraction by the Penrose process in a rotating Bardeen black hole surrounded by PFDM.展开更多
文摘由于可再生能源和负荷的不确定性,电力系统潮流分析需要有效的工具。目前的多数研究都假设一组给定的概率密度函数(PDF:Probability Density Functions)建模不确定性,并开发参数概率潮流工具。为此,提出了一种非参数概率潮流分析方法确定潮流输出的偏微分方程。该方法基于平均值一阶鞍点近似。对于n个随机变量系统,利用潮流计算建立一阶Taylor级数展开,然后采用鞍点近似确定期望输出变量的概率特性。所提出的非参数估计器在需要合理的计算量的同时,能提供精确的结果。此外,在不使用积分或微分算子的情况下,直接建立了潮流输出的概率分布函数和累积分布函数。在IEEE 14总线和IEEE 118总线测试系统上进行了测试,所得结果与其他方法相比,MVFOSPA(Mean Value First Order Saddle Point Approximation)比MCS(Monte Carlo Simulation)算法运行时间减少了12%,验证了MVFOSPA方法的有效性。
基金the National Natural Science Foundation of China(11571342)。
文摘We derive an exact solution for a spherically symmetric Bardeen black hole surrounded by perfect fluid dark matter(PFDM).By treating the magnetic charge g and dark matter parameter a as thermodynamic variables,we find that the first law of thermodynamics and the corresponding Smarr formula are satisfied.The thermodynamic stability of the black hole is also studied.The results show that there exists a critical radius r+C where the heat capacity diverges,suggesting that the black hole is thermodynamically stable in the range 0 <r+<r+C. In addition,the critical radius r+C increases with the magnetic charge g and decreases with the dark matter parameter a.Applying the Newman-Janis algorithm,we generalize the spherically symmetric solution to the corresponding rotating black hole.With the metric at hand,the horizons and ergospheres are studied.It turns out that for a fixed dark matter parameter a,in a certain range,with the increase of the rotation parameter a and magnetic charge g,the Cauchy horizon radius increases while the event horizon radius decreases.Finally,we investigate the energy extraction by the Penrose process in a rotating Bardeen black hole surrounded by PFDM.
