基于LCL滤波器的单相光伏并网三环控制策略

Single-phase Photovoltaic Grid-loop Control Strategy Based on LCL Filter

引入LCL滤波器代替L型和LC型滤波器。分析了有源阻尼算法,针对在光照过强的条件下由于输入功率和输出功率不匹配出现的直流母线过电压现象,提出直流母线电压环、电网电流环、电容电流环三环控制策略,稳定直流母线电压。搭建了单相光伏并网控制系统模型,详细分析了所设计的控制策略,仿真结果表明,采用新型控制策略能有效控制直流母线电压,改善入网电流品质,提高系统的稳定性。

Based on LCL filter instead of L and LC type filter,through active damping algorithm,in response to the DC bus overvoltage phenomenon due to the mismatching of input and output power when the light is too strong ,this paper proposes the loop control strategy of DC bus voltage loop,current loop power and capacitor current loop in order to stabilize DC bus voltage. A single-phase photovoltaic grid control system model is estab-lished and a detailed analysis of the design of the control strategy is carried out. The simulation results show that the new control strategy can effectively control the DC bus voltage,improving current quality and system stability.