This paper proposes a hybrid decoupled power flow method for balanced power distribution systems with distributed generation sources. The method formulates the power flow equations in active power and reactive power d...This paper proposes a hybrid decoupled power flow method for balanced power distribution systems with distributed generation sources. The method formulates the power flow equations in active power and reactive power decoupled form with polar coordinates. Second-order terms are included in the active power mismatch iteration, and constant Jacobian and Hessian matrices are used. A hybrid direct and indirect solution technique is used to achieve efficiency and robustness of the algorithm. Active power correction is solved by means of a sparse lower triangular and upper triangular （LU） decomposition algorithm with partial pivoting, and the reactive power correction is solved by means of restarted generalized minimal residual algorithm with an incomplete LU pre-conditioner. Typical distribution generation models and distribution load models are included. The impact of zero-impedance branches is explicitly modeled through reconfiguring of the adjacent branches with impedances. Numerical examples on a sample distribution system with widespread photovoltaic installations are given to demonstrate the effectiveness of the proposed method.展开更多
Recently,power electronic transformers(PETs)have received widespread attention owing to their flexible networking,diverse operating modes,and abundant control objects.In this study,we established a steady-state model ...Recently,power electronic transformers(PETs)have received widespread attention owing to their flexible networking,diverse operating modes,and abundant control objects.In this study,we established a steady-state model of PETs and applied it to the power flow calculation of AC-DC hybrid systems with PETs,considering the topology,power balance,loss,and control characteristics of multi-port PETs.To address new problems caused by the introduction of the PET port and control equations to the power flow calculation,this study proposes an iterative method of AC-DC mixed power flow decoupling based on step optimization,which can achieve AC-DC decoupling and effectively improve convergence.The results show that the proposed algorithm improves the iterative method and overcomes the overcorrection and initial value sensitivity problems of conventional iterative algorithms.展开更多
随着电力系统的快速发展和复杂性日益增加,最优潮流(Optimal Power Flow,OPF)计算作为电力系统分析的关键环节,对于提高电网的运行效率和可靠性具有重要意义。文章提出了一种基于自适应人工蛙跳觅食算法的最优潮流计算方法,旨在解决传...随着电力系统的快速发展和复杂性日益增加,最优潮流(Optimal Power Flow,OPF)计算作为电力系统分析的关键环节,对于提高电网的运行效率和可靠性具有重要意义。文章提出了一种基于自适应人工蛙跳觅食算法的最优潮流计算方法,旨在解决传统最优潮流计算方法在处理大规模非线性问题时的不足。为了解决算法在处理复杂电力系统问题时存在收敛速度慢和易陷入局部最优的问题,文章引入自适应策略,通过动态调整算法参数,提高算法的全局搜索能力和收敛速度。仿真实验结果表明,所提出的方法在解的质量、收敛速度和算法稳定性方面均表现出显著的优势。展开更多
文摘This paper proposes a hybrid decoupled power flow method for balanced power distribution systems with distributed generation sources. The method formulates the power flow equations in active power and reactive power decoupled form with polar coordinates. Second-order terms are included in the active power mismatch iteration, and constant Jacobian and Hessian matrices are used. A hybrid direct and indirect solution technique is used to achieve efficiency and robustness of the algorithm. Active power correction is solved by means of a sparse lower triangular and upper triangular （LU） decomposition algorithm with partial pivoting, and the reactive power correction is solved by means of restarted generalized minimal residual algorithm with an incomplete LU pre-conditioner. Typical distribution generation models and distribution load models are included. The impact of zero-impedance branches is explicitly modeled through reconfiguring of the adjacent branches with impedances. Numerical examples on a sample distribution system with widespread photovoltaic installations are given to demonstrate the effectiveness of the proposed method.
基金supported by the National Key Research and Development Program of China(2017YFB0903300).
文摘Recently,power electronic transformers(PETs)have received widespread attention owing to their flexible networking,diverse operating modes,and abundant control objects.In this study,we established a steady-state model of PETs and applied it to the power flow calculation of AC-DC hybrid systems with PETs,considering the topology,power balance,loss,and control characteristics of multi-port PETs.To address new problems caused by the introduction of the PET port and control equations to the power flow calculation,this study proposes an iterative method of AC-DC mixed power flow decoupling based on step optimization,which can achieve AC-DC decoupling and effectively improve convergence.The results show that the proposed algorithm improves the iterative method and overcomes the overcorrection and initial value sensitivity problems of conventional iterative algorithms.
文摘随着电力系统的快速发展和复杂性日益增加,最优潮流(Optimal Power Flow,OPF)计算作为电力系统分析的关键环节,对于提高电网的运行效率和可靠性具有重要意义。文章提出了一种基于自适应人工蛙跳觅食算法的最优潮流计算方法,旨在解决传统最优潮流计算方法在处理大规模非线性问题时的不足。为了解决算法在处理复杂电力系统问题时存在收敛速度慢和易陷入局部最优的问题,文章引入自适应策略,通过动态调整算法参数,提高算法的全局搜索能力和收敛速度。仿真实验结果表明,所提出的方法在解的质量、收敛速度和算法稳定性方面均表现出显著的优势。
