基于P-V下垂系数修正的并联逆变器输出功率成比例分配实现

Proportional Load Sharing for Parallel Inverter Systems Based on Modified P-V Droop Coefficient

为了确保并联逆变器在连接线路阻抗存在明显差异的情况下,仍然能按其额定输出容量成比例地输出功率,详细分析了功率分配不成比例的根本原因,给出逆变器输出阻抗和线路参数间的关系,进而提出主动注入功率差额实现功率比例分配的解决方法,给出易于工程实现的P-V下垂系数基准校正曲线。提出的方法可以根据实测的线路参数,也可仅在并联系统调试或运行过程中进行一次P-V下垂系数的修正实现功率的比例分配。多工况的仿真和实验结果验证了提出方法的有效性。

In order to realize proportional load sharing of parallel inverters in proportion to the inverters volumes under different line impedances, an active power injecting method is presented. After analyzing the key reason about disproportional load sharing of the parallel inverter, this paper analyzes the relationship between the line impedance and the output active power of the inverter, and further presents the proportional load sharing method for parallel inverters. The correction curve of P-V droop coefficient is also provided. The presented method can implement proportional load sharing based on the field line impedances or one time P-V droop coefficient correction during debugging or running process of the inverters. Simulation and experimental results validate the feasibility and superior performance of the presented method.