基于寿命模型的混合储能参与二次调频的经济性研究

Economic Feasibility in Secondary Frequency Regulation Considering Hybrid Energy Storage Cycle Life Model

针对储能电池在参与电网二次调频过程中的寿命损耗问题,提出一种计及电池寿命的混合储能参与调频的控制策略。在含有磷酸铁锂电池和铅炭电池的混合储能系统中,考虑放电深度、循环使用次数等因素,建立电池寿命模型;在功率分配环节,利用一阶低通滤波器对区域控制需求信号进行高低频的划分;综合考虑混合储能损耗、调频需求及评价指标等约束,以滤波时间常数为优化变量,进而建立以经济效益最大为目标的混合储能系统调频模型。利用Matlab/Simulink对含有混合储能的区域电网二次调频模型进行仿真验证,结果表明该模型不仅能有效改善调频性能,而且对降低电池损耗及后期更换成本具有重要意义。

In allusion to the life loss of the energy storage battery participating in the secondary frequency regulation of power grid,a control strategy for hybrid energy storage participating in frequency regulation,in which the lifetime of the battery was taken into account,was proposed.Firstly,in a hybrid energy storage system containing lithium iron phosphate battery and lead-carbon battery,considering such factors as the depth of discharge,the cycle times and so on,a battery life model was built.Secondly,in the link of power distribution,the first order low pass filter was utilized to divide the high frequency signal in area regulation requirement from the low frequency signal.And then,overall considering such constraints as loss of hybrid energy storage,demand of frequency regulation and evaluation indices and taking the filtering time constant as the optimization variable,a frequency regulation model of hybrid energy storage system,which took the maximized economic benefit as the object,was established.This secondary frequency regulation model of regional power grid containing hybrid energy storage was simulated and verified by Matlab/Simulink,and simulation results show that the proposed model not only can improve the frequency regulation performance effectively,but also possesses importance in reducing both battery loss and later-stage replacement cost.