一种改进的电压暂降概率评估方法

An improved method for assessment of voltage sag probability

针对电压暂降随机预估中传统蒙特卡洛法认为线路长度是影响线路故障率唯一影响因素的缺陷,提出了一种改进的电压暂降概率评估方法.构建了包含线路自身属性及多种客观因素的线路故障概率评估体系;并结合该评估体系,建立了完善的短路故障模型,在PSCAD/EMTDC搭建IEEE-30节点系统仿真模型,运用随机数发生模块和Multiple Run组件对故障信息进行抽样和传送,通过仿真计算得到敏感负荷接入点的电压暂降特征量和评估指标的概率分布.仿真结果表明,改进的蒙特卡洛法相比于蒙特卡洛法在电压暂降概率评估中更接近电网的真实状况,验证了该方法的有效性.

Aimed at the shortage of the traditional Monte Carlo method for stochastic assessment of voltage sags, where the length of transmission line is taken as the unique influencing factor on line failure rate, an improved method for assessment of voltage sag probability is proposed. A probability assessment system of line fault is established, in which the attribute of the line proper and variety of objective factors are included and with the aid of it, a perfect short-circuit fault model is established. The IEEE-30 nodal system simulation model is then established on PSCAD/EMTDC, the random number generation module and Multiple Run component are used to sample and transmit the fault information, and the probability distribution of voltage sag characteristic variable and assessment index of the sensitive load access point are obtained by means of simulative evaluation. The simulation result shows that compared to original Monte Carlo, the improved method for assessment of voltage sag probability will be closer to real condition of grid system and the effectiveness of this method will be verified.