恒频滞环电流控制的单相光伏并网逆变器

摘要

Based on the mathematical models of photovoltaic module practical in engineering,the module simulation model is established in PSIM software for the output quickly and dynamically changing with light intensity and temperature, and the output electrical characteristics of the PV module is analyzed by simulation.Meanwhile an algorithm is proposed to achieve MPPT,and its validity has been verified.Grid-connected inverter is a key electrical element of grid-connected PV system,influencing power quality and system stability.The grid-connected inverter under constantfrequency hysteresis current control is adopted,and the dynamic simulation model is built for the grid-connected singlephase PV system.The simulation results verify that the single-phase PV grid-connected inverter under constant-frequency hysteresis current control can track public grid quickly and effectively,output grid-connected current with low harmonic distortion rate,and enhance the stability and dynamism of grid-connected PV system,as well as its output efficiency.%基于符合工程实际的光伏模块数学模型,在PSIM软件中建立输出能快速动态随光照强度与温度变化的模块仿真模型,通过仿真分析光伏模块的输出电气特性。同时提出一种实现模块最大功率跟踪算法,并验证其有效性。光伏并网发电系统中的关键部件并网逆变器,影响电能质量与系统稳定。采用恒频滞环电流跟踪控制下的并网逆变器,建立单相光伏并网发电系统的动态仿真模型,仿真结果验证了恒频滞环电流控制光伏并网逆变器能够快速有效地跟踪公共电网,输出谐波畸变率低的并网电流,改善并网系统稳定性与动态性,提高光伏系统输出效率。