随着分布式发电技术的不断推广和发展,大量DG(分布式发电)以微网形式接入配电网.文中以风储互补微网为对象,根据互补微网在配电网中的运行方式,采用蒙特卡洛仿真算法,从负荷点和系统两个层面上给出了配电网中常用的几项可靠性指标;在分析了随机电源特点的基础上,建立风储互补微网可靠性评估模型;根据传统配电网可靠性计算结果对风力DG进行选址,在确定储能配置后形成了计划型孤岛范围;提出由于风储微网内负荷和风力DG出力的时变性,在孤岛内有可能发生储能放电过量,从而导致微网解列的二次故障问题.对风储互补微网接入后的配电网的蒙特卡洛可靠性仿真结果表明,风储互补微网能有效提高配电系统的可靠性.
With the application and development of distributed generation technologies,a large number of distributed generators (DGs) are installed in the form of microgrid.In this paper,first,by taking the wind-storage complementary microgrid as an example and by considering the operation mode of the wind-storage complementary microgrid in distribution networks,several reliability indices of load and system are calculated via the Monte Carlo simulation algorithm.Next,after analyzing the characteristics of random power sources,a reliability evaluation model of the wind-storage complementary microgrid is established.Then,a site selection of wind-power DGs is carried out according to the simulated reliability results,and an island is planned after determining the energy storage capacity.Moreover,the possibility of malfunction of microgrids after the island formation,which is due to the running out of energy storage caused by the time-varying load and the DG output,is discussed.Finally,a reliability simulation is performed with the Monte Carlo method for the power distribution network with the wind-storage complementary microgrid.It is found that the reliability greatly improves when a microgrid is connected.