由于风速变化对大规模风电并网后的电力系统电压稳定造成影响,提出了对风速进行模糊模拟的可信性静态电压稳定分析方法。该方法不仅能够计算出含有不确定因素时系统降阶雅可比矩阵对角元素的期望值和均方差,而且建立了基于可信性意义下的静态电压稳定指标。该方法避免了不确定参数分布函数类型的假设和参数统计对分析结果的影响,仅需根据不确定参数的实际变化范围和描述不确定参数的隶属度函数类型确定计算结果。最后,与采用两点估计法和蒙特卡洛仿真法后的计算结果进行对比,证明了所提方法在计算精度和计算量方面的优越性。
The variation of wind speed influences the voltage stability of power system with large-scale wind power,to which,a method of static voltage stability analysis based on credibility theory is proposed for the fuzzy simulation of wind speed. It not only calculates the expectations and mean square errors of the diagonal elements of the order-reduced Jacobian matrix with uncertain parameters but also determines the static voltage stability indexes based on the credibility theory. The calculated results depend on the actual variation range of uncertain parameter and its membership function type only,the impacts of the statistics of uncertain parameter and the assumption of its distribution function type on the analytic results are thus avoided. The calculated results of the proposed method are compared with those of the two-point probabilistic analysis method and Monte Carlo simulation method,verifying its superiority in the accuracy and calculation load.