基于遗传算法的微电网负荷优化分配

Power Economic Dispatch of Microgrid Based on Genetic Algorithm

负荷优化分配是电力系统中的一类重要优化问题,即在满足各类系统约束条件下,实现发电总成本最低。为了促进微电网的优化运行,本文研究了包含柴油发电机、微型燃气轮机、光伏发电机和风力发电机组成的微电网的负荷优化分配问题。首先简要分析了各个微电源的发电特征和成本函数,然后分别建立了孤岛模式和并网模式下的微电网负荷优化分配模型,孤岛模式下优化模型的目标函数是包含燃料成本和运行维护成本的总成本,约束条件包括发电能力约束和系统功率平衡约束,并网模式下的优化模型则在此基础上,在目标函数中增加了其与大电网交易的收入和支出,在约束条件中增加了电力交易约束。最后,通过遗传算法分别对两种模式下的优化模型进行仿真求解。结果表明,本文提出的负荷优化分配方法可以有效降低微电网的运行成本,促进微电网的优化运行。

Power economic dispatch is an important kind of optimization problem in the power systems, that is, achieving the lowest tatal cost of power generation while meet many kinds of system constraints. In order to promote the optimal operation of microgrid, the power economic dispatch problem is studied in this paper of the microgrid with diesel generator, microturbine, photovoltaic power generator and wind turbine. At first, the generation characteristics and cost functions of the micro power generators are ana- lyzed. Then the power economic dispatch models under islanded mode and grid-connected mode are con- structed respectively. The objective function of the optimization model under islanded mode is the total costs which include the fuel costs and operation maintance costs, and the constraint conditions include the constraint of power generation and the constraint of system power balance. While the income and expenses of the transaction between microgrid and the large power grids are added to the objective function of the optimization model under grid--connected model based on the model under islanded mode, and the electric- ity transaction constraint are added to the constraint conditions. Finally, the optimization models under both modes are solved by genetic algorithm. The results show that the power economic dispatch method proposed in this paper can effectively reduce the operating costs and promote the optimal operation of mi- crogrid.