考虑不确定因素影响的微电网供电能力评价方法

Evaluation method of power supply capacity of micro-grid considering the influence of uncertain factors

针对风电、光伏、负荷的不确定性对微电网短期供电能力的影响,文章将风电、光伏、负荷的预测误差分布与蒙特卡罗抽样法相结合,建立一种考虑风电、光伏、负荷不确定性的微电网短期供电能力评价方法。通过非参数方法对微电网中风电、光伏、负荷进行确定性预测,并对风电、光伏、负荷的预测误差进行了概率分析;通过蒙特卡罗抽样法对风电、光伏、负荷的预测误差模型进行抽样,并结合风电、光伏、负荷的确定性预测结果获得可能出现的微电网场景;定义了多个可用于量化供电能力的评价指标,针对每一个微电网场景优化求解计算出微电网供电能力的评价指标。选取某微电网作为算例,对所提方法进行了验证,算例结果表明,所提方法能够准确地反映在不同天气类型下的微电网供电能力。

In order to study the influence of wind power,photovoltaic and load uncertainty on short-term power supply capacity of micro-grid,this paper combines the prediction error probability distribution of wind power,photovoltaic and load with Monte-Carlo sampling method to establish a short-term power supply capacity evaluation method of micro-grid considering wind power,photovoltaic and load uncertainty.A deterministic prediction of wind power,photovoltaic and load is carried out by means of autoregressive non-parametric method,and then,the prediction error of wind power,photovoltaic and load is analyzed probabilistically.The Monte-Carlo sampling method is used to sample the prediction error models of wind power,photovoltaic and load,and combined with the deterministic prediction results of wind power,photovoltaic and load,the possible scenarios of the micro-grid are obtained;Several evaluation indices which can be used to quantify the power supply capacity are defined,and the evaluation index of the power supply capacity of the micro-grid is calculated according to the optimal solution of each scenario of the micro-grid.A micro-grid is selected as an example to verify the proposed method,and the results show that the method proposed in this paper can accurately reflect the power supply capacity of the micro-grid under different weather types.