考虑随机特性的微电网电源优化配置

Optimal Siting and Sizing of Distributed Generation Planning in Microgrid by Considering Stochastic Characteristic

对孤岛运行微电网进行合理地电源配置是保证其可靠经济运行的关键问题之一。以电源类型、接入位置与容量为待求变量,综合经济成本最低为目标函数,微电网节点电压为主要约束条件,建立了数学模型,并采用粒子群算法求解。考虑到常见微电网电源如风能、太阳能的随机特性,根据不同类型电源出力概率模型,采用蒙特卡洛法模拟电源的出力,并结合确定性潮流算法,建立了随机潮流计算方法。使用该随机潮流计算方法得到不同电源配置方案孤岛微电网的节点电压越限率,以此评价配置方案的可靠性。算例表明,使用该方法对孤岛微电网的电源进行配置,可以在控制投资成本的同时,有效地将节点电压越限率控制在较低水平,满足了经济性和可靠性的要求。

Optimal siting and sizing of distributed generation （DG） planning in a stand-alone microgrid is an important issue to make microgrid operate reliably and economically. In this paper a mathematical model for optimal sizing of DG was established. The model took types, sites and sizes of DG as the variables, minimum overall cost as the objec- tive function and node voltage as the constraints. The particle swarm optimization algorithm was proposed to solve the optimization problem. As the common DG such as wind and solar energy have the characteristics of randomness and waviness, Monte Carlo method was used to simulate DG＇s characteristics based on probability distribution model of different types of DG. Combining with the deterministic power flow method, a probabilistic power flow method was estab- lished. This method was used to judge whether the node voltage of microgrid was out of range under certain DG config- uration. A case study shows that, using this method to configure DG can both control costs and make the node voltage in a proper range, which can meet the needs of economy and reliability.