基于SMDP的光柴储独立微网能量控制策略优化

考虑含光伏发电装置、储能装置和柴油发电机组的独立微网系统,以提高微网长期运行经济性为目标,研究微网能量管理优化问题。首先对系统的随机动态特性进行建模,即针对光伏发电和负荷变化的随机特性,将微网系统的能量控制建模为半马尔可夫决策过程(SMDP);然后采用随机动态规划算法对最优策略进行求解,得到微网在不同的光伏发电功率、负荷需求、储能荷电状态等级和柴油发电机组运行数量下对柴油发电机组和储能装置的最优控制行动。仿真结果说明了所建随机模型的合理性和优化方法的有效性。

SMDP Based Optimization of Energy Control Strategy for Photovoltaic-diesel-battery Stand-alone Microgrid

This paper presents an optimal control model for photovoltaic-diesel-battery stand-alone system. To minimize the long-term operating cost, the control strategy for the battery and diesel generators is optimized. That is, for the stochastic characteristics of the photovoltaic output and load demand, the energy control of the system is modeled as a semi-Markov decision process(SMDP). The system state is composed of the states of photovoltaic power and load demand, the quantity of operating diesel generators and the levels of battery state of charge. A stochastic dynamic programming method is adopted to find the optimal control strategy consisting of optimal actions for each state. The simulation result shows the rationality of the stochastic model and the effectiveness of the optimization method. This work is supported by National Natural Science Foundation of China(No. 61573126), Program for New Century Excellent Talents in University(No. NCET-11-0626)and Specialized Research Fund for the Doctoral Program of Higher Education(SRFDP)of China(No. 20130111110007).