基于级联式模糊控制的电氢耦合直流微网能量管理策略研究

An energy management strategy for an electricity-hydrogen coupled DC microgrid based on cascade fuzzy control

针对电氢混合储能系统在平抑直流微网中功率波动时面临的功率分配问题,提出了一种基于级联式模糊控制的电氢耦合直流微网能量管理策略。该策略中一次模糊控制器依据储氢罐储氢状态(stateofhydrogenstorage,SOH)与锂电池荷电状态(state of charge, SOC)求解出一次功率分配因子,对直流微网净功率进行一次分配;二次模糊控制器结合一次功率分配参考值与SOH对一次功率分配因子作出校正。此外,为使氢储能系统中具有非线性工作特性的电流控制型装置(电解槽、燃料电池)能够对能量管理系统作出高效响应,采用插值法将功率分配参考值转换为电流参考值。通过Matlab/Simulink仿真结果证明,所提能量管理策略有效缩小了氢储能系统在非合理区间的功率波动范围并提高了氢储能系统中装置的响应精度与速度。

An energy management strategy for an electricity-hydrogen coupled DC microgrid based on cascade fuzzy control is proposed to address the power allocation problem faced by an electricity-hydrogen hybrid energy storage system when smoothing out power fluctuations in a DC microgrid.In this strategy,the primary fuzzy controller works out the primary power allocation factor based on the state of hydrogen storage(SOH)of the hydrogen storage tank and the state of charge(SOC)of the lithium-ion battery and performs primary allocation of the DC microgrid net power.The secondary fuzzy controller combines the reference value of primary power allocation and the SOH to correct the primary power allocation factor.In addition,to enable current-controlled devices(electrolysers and fuel cells)with nonlinear operating characteristics to respond efficiently to the energy management system,an interpolation method is used to convert the power distribution reference value to a current reference value.Matlab/Simulink simulation results prove that the strategy effectively narrows the power fluctuation range in the unreasonable range and improves the accuracy and speed of the device response in the system.