DG出力不确定性对配电网影响力分析的复仿射数学方法

Complex Affine Arithmetic Based Method for the Analyses of DG's Uncertainty Influence on Distribution Network

风力、光伏发电受天气变化影响,功率输出具有随机性和不确定性。大量风力、光伏发电系统以分布式电源形式接入配网,导致了配电网潮流的不确定性。采用仿射数表达分布式电源出力的不确定性,提出了基于仿射数学的三相前推回代仿射潮流算法解决配电网不确定潮流问题。仿射数能够记录不确定变量之间的相关性,利用此性质提出了不确定变量相对影响力指标。采用33节点典型配电系统进行验证分析,结果表明,所提指标能够定量分析分布式电源出力不确定性对配电网各节点电压的影响情况。

Weather conditions have the property of intermittence and randomness which directly incur the uncertainty of power output of wind generators and photovoltaic systems. The integration of these variable and intermittent power sources into distribution power system results in widespread uncertainties of distribution power flows. The affine numbers was applied to describe the uncertainty of power output of distribution generation, and an affine arithmetic-based three-phase forward-backward sweep power flow calculation method was proposed to solve the uncertainty power flow problem. The affine number can keep track on the correlations between each variables, based on this property, the index of influence of uncertain variables on outcomes was proposed. The proposed method was tested on the 33-bus distribution system and the results show that the proposed index can quantify the impacts of individual distribution generation uncertain factors on each bus voltages in the distribution power system.