分布式光伏发电并网数字化建模与仿真

Digital Modeling and Simulation of Grid-Connected Distributed Photovoltaic Power Generation

为了改善光伏发电性能,需要对分布式光伏发电并网控制技术进行研究。提出基于MPPT控制的分布式光伏发电并网建模方法,建立光伏电池模型,在所建模型的基础上研究光伏发电系统输出功率受光照强度变化的影响。并利用MPPT控制方法跟踪分布式光伏系统的最大功率点,提高分布式光伏系统在运行过程中的输出功率。通过滑膜控制对光伏并网逆变器进行控制,保持电网电压与光伏发电系统输出电流的同步性,实现分布式光伏系统并网发电。通过仿真,验证了所提方法可有效地实现光伏阵列最大输出功率的跟踪,满足分布式光伏发电并网系统的运行要求。

In order to improve the performance of photovoltaic power generation, it is necessary to research the grid-connected control technology of distributed photovoltaic power generation. This paper put forward an approach for modeling a grid-connected system of distributed photovoltaic power based on MPPT control and then built a photovoltaic cell model. Based on this model, the influence of the changes of light intensity on the output power of the photovoltaic power system was researched. Meanwhile, the MPPT control method was adopted to track the maximum power point of the system and thus to improve the output power during operation. Moreover, the sliding mode control was used to control the photovoltaic grid-connected inverter, thus maintaining the synchronization between grid voltage and output current of the photovoltaic power generation system. Finally, the grid-connected power generation of the distributed photovoltaic system was achieved. The simulation results verified that the proposed method effectively tracked the maximum output power of the photovoltaic array and fulfilled the operation requirements of the distributed photovoltaic power grid-connected system.