光柴储微网系统的储能动态能量调度策略研究

Study on dynamic energy dispatch strategy of energy storage in PV-diesel-energy storage microgrid system

针对光柴储微网中负荷突变和光伏微源输出功率随机波动引起的系统频率波动问题,给出一种基于频率偏差的储能动态能量调度策略。根据柴油发电机频率偏差的产生机理,结合微网系统电能质量和稳定运行要求,提出三段式PD先行的储能动态调度策略,克服了基于比例-微分(PD)储能动态调度策略的不足。将该储能动态策略应用于实际的微网实验平台中,并对两种情况进行实验分析比较,以验证其对频率波动的抑制作用。实验结果表明,该改进策略确能在一定程度上改善由负荷突变和光伏波动造成的系统频率波动问题,为提高微网系统供电质量和稳定性提供了一种可行性方案。

A dynamic energy dispatch strategy based on frequency bias is presented for the photovoltaic-diesel-energy storage microgrid, which aims at frequency fluctuation caused by the sudden change of load and the characteristic of photovoltaic microsource. According to the frequency bias forming principle of diesel generator and the demand for steady operation and power quality of microgrid, a three-stage dynamic energy dispatch strategy based on proportional-derivative （PD） preceding is achieved, which overcomes the shortcoming of PD strategy. This modified strategy is implemented in the esta.blished microgrid system, and two pairs of contrast experiments are made to verify the suppression effect of system frequency fluctuation. The experiments have proved that this strategy for dynamic energy dispatching can mitigate the frequency fluctuation caused by photovoltaic microsource and load sudden change to some extent, thus it is a feasible solution to improving power quality and stability of microgrid.