【摘要】 当原有的户用式光伏并网发电系统升级为家庭光储系统时,单相光伏并网逆变器需在储能电池等电压源输入条件下仍能正常并网运行。首先,建立了光伏阵列与锂电池组等效电路数学模型,分析与验证了在电压源输入条件下,两级式单相系统的二次纹波污染比光伏阵列输入条件下严重的现象。然后,通过分析两级式单相系统中的交直流耦合机理与Boost电路数学模型的建立,提出一种电流双反馈式纹波电流抑制措施。采取基于广义三阶积分的纹波提取与直流侧中间电压纹波的陷波抑制算法优化系统并网运行控制,并利用MATLAB对控制系统进行仿真分析与计算。最后,搭建了5kW并网实验系统,通过实验结果验证了所提控制策略的有效性与实用性。更多还原

【Abstract】 When the original photovoltaic system is upgraded to family photovoltaic energy storage system,the single-phase photovoltaic inverter should meet the need of continued grid-connected operation under energy storage battery input condition.Firstly,equivalent circuit of photovoltaic array and Li-ion battery pack are constructed and studied.Based on these math models,comparison of the impacts brought about by two different input conditions is made.Under energy storage battery input condition,for the inherent AC/DC coupling problem in single-phase inverter,there is more serious contamination of the second harmonic current.Then,the equivalent impedance of ripple current based on Boost DC/DC convertor small signal mode is studied.A novel active input ripple current mitigating technique based on double channel current feedback is proposed.The control system using extraction method of ripple component and trap inhibition for ripple voltage in DC-link,based on the third-order general integrator,is analyzed and simulated with MATLAB.Finally,experimental results using a 5kW prototype have validated the proposed control strategy.更多还原