含经VSC-HVDC并网海上风电场的交直流系统概率最优潮流

Probabilistic optimal power flow of AC / DC system with offshore wind farm connected to grid via VSC-HVDC

由于海上风速的不确定性,海上风电场并网会对电力系统最优潮流(OPF)产生影响,提出含基于电压源换流器的高压直流输电(VSC-HVDC)并网海上风电场的交直流系统概率最优潮流计算模型。首先,利用非参数核密度估计拟合海上风速分布,建立海上风电场和VSC-HVDC的稳态模型;然后,基于拉丁超立方采样得到标准正态分布样本,利用等概率变换理论和Nataf变换技术得到具有相关性的输入变量样本;最后,采用原对偶内点法进行OPF计算,得到输出变量的样本,利用统计学方法得到输出变量的数字特征和概率分布。IEEE 14节点和IEEE 118节点系统仿真结果验证了算法的准确性和高效性。

The grid-connection of offshore wind farm impacts the OPF（Optimal Power Flow） of power system due to the uncertainty of offshore wind speed and a probabilistic optimal power flow calculation model of AC / DC system with offshore wind farm connected to grid via VSC-HVDC（Voltage Source Converter based High Voltage Direct Current） is proposed. The nonparametric kernel density estimation is adopted to fit the distribution of offshore wind speed and the steady-state models of offshore wind farm and VSC-HVDC are built. The standard normal distribution samples are obtained by Latin hypercube sampling and the input variable samples with correlation are obtained based on the equivalent possibility transformation and Nataf transformation. The primal-dual interior-point method is applied in the OPF calculation to obtain the output variable samples and the statistical method is used to obtain its numeric characteristics and probability distribution. The simulative results of IEEE 14-bus system and IEEE 118-bus system verify the correctness and efficiency of the proposed method.