基于模糊理论的柔性配电网多储能SoC均衡控制策略研究

Research on Balanced Control Strategy of Energy Storage SoC Based on Fuzzy Rules

光伏和风电等分布式电源在柔性配电网中的渗透率不断提高,为减弱其间歇性出力对电力系统的不利影响,引入了储能系统。但由于各储能单元在电池特性、硬件参数配置等方面存在差异,将导致储能单元的有效使用寿命缩短。本文针对分布式储能单元SoC不均衡及输出电压波动的问题,提出一种基于模糊理论的SoC均衡控制方法。以各储能单元的荷电状态和储能端口的电压偏差量为模糊控制的输入,得到各储能单元的参考电压叠加值;以此间接控制DC/DC变换器,改变储能单元的输入/输出电流,从而实现对储能单元的充放电控制;最终使剩余电量达到均衡,同时维持储能系统输出电压稳定。利用PSCAD仿真软件对文中的基于模糊理论的柔性配电网多储能SoC均衡控制策略进行仿真,证明了所提方法的有效性。

The penetration of distributed power sources such as photovoltaic and wind power in the flexible distribution network is increasing.In order to reduce the adverse impact of intermittent output on the power system,the energy storage system is introduced.However,due to the differences in battery characteristics,hardware parameter configuration and other aspects of each energy storage unit,the effective service life of the energy storage unit will be shortened.Aiming at the problem of SoC imbalance and output voltage fluctuation of distributed energy storage unit,this paper proposes an SoC equalization control method based on fuzzy theory.Taking the state of charge of each energy storage unit and the voltage deviation of the energy storage port as the input of fuzzy control,the reference voltage superposition value of each energy storage unit is obtained.This indirectly controls the DC/DC converter to change the input/output current of the energy storage unit,thus realizing the charge and discharge control of the energy storage unit.Finally,the remaining power is balanced and the output voltage of the energy storage system is stable.In the PSCAD simulation software,the fuzzy theory based SoC balancing control strategy for flexible distribution network is simulated and verified,which proves the effectiveness of the proposed method.