摘要
针对光储DC/DC变换器带逆变器负载造成光伏最大功率点追踪(MPPT)抖动的问题,提出一种直流电压前馈与负载识别的MPPT抖动抑制方法。蓄电池电压二倍频波动及其诱发的系统工作模式动态切换是造成MPPT抖动的主要原因。首先基于蓄电池Thevenin等效模型,分析逆变负载下蓄电池各等效参数对直流母线电压脉动的作用机理并建立含蓄电池等效参数的DC/DC变换器反向增益模型,随后提出母线电压波动耦合的前馈抑制方法。进一步根据蓄电池MPPT充电模式、恒压-恒流充电模式的切换关系,分析逆变负载导致工作模式不稳定切换的诱因,提出一种负载识别方法,通过时间窗检测直流母线电压脉动情况作为环路切换附加判据,有效规避工作模式的动态切换。仿真和实验结果表明所提组合方法可有效降低逆变器负载下光储DC/DC的MPPT抖动。
This paper introduces a novel control method to address maximum power point tracking(MPPT)ripple in photovoltaicstorage DC/DC converter under inverter load.The double-line frequency of the battery voltage pulsation and the resulting dynamic mode switching of system is the main cause of MPPT ripple.Firstly,the effect of battery’s equivalent parameters under inverter load on DC bus voltage pulsation is analysed based on the Thevenin equivalent model,and a back gain model incorporating the battery’s equivalent parameters of DC/DC converter is established.Additionally,a feedforward method is proposed for suppressing bus voltage pulsation.Furthermore,an analysis is conducted to identify the causes of dynamic mode switching induced by inverter loads based on the relationship between MPPT charging mode and constant voltage-constant current charging mode.A load identification algorithm is proposed to avoid dynamic mode switching,by using a time window to detect bus voltage pulsation as an additional loop switching criterion.Finally,simulation and experimental results show that the proposed combined method can effectively reduce MPPT ripple in the photovoltaic-storage DC/DC converter under inverter load.
作者
刘宝泉
张浩铭
李昊轩
韩猛
Liu Baoquan;Zhang Haoming;Li Haoxuan;Han Meng(School of Electrical and Control Engineering,Shaanxi University of Science and Technology,Xi’an 710021,China)
出处
《太阳能学报》
北大核心
2025年第3期384-393,共10页
Acta Energiae Solaris Sinica
基金
陕西省自然科学基础研究计划(2023-JC-YB-381)
陕西省2020年重点研发计划(2020GY-042)。
关键词
光储系统
直流变换器
最大功率点跟踪
光伏电压脉动
模式动态切换
photovoltaic-storage system
DC/DC converter
maximum power point tracking(MPPT)
photovoltaic voltage fluctuation
dynamic mode switching
