带限功率控制的光伏并网逆变器控制策略研究

Research on Control Strategy of PV Grid-connected Inverter with Constrained Production

光伏组件的输出功率会随着光照强度和温度等的变化而变化,为了减少光伏发电系统的波动性,避免微电网与公共电网交换峰值功率,在研究光伏发电系统的最大功率点跟踪(MPPT)控制的基础上,研究光伏发电系统的限功率控制,即在限定功率以下,以输出最大功率为目标,而在限定功率以上,主要以限定功率为控制目标。建立双级式光伏发电系统的模型,研究前级Boost升压电路的MPPT控制和限功率控制的实现方法,研究后级DC-AC变换器的矢量控制技术;最后在MATLAB/SIMULINK中建立了系统的仿真模型,仿真结果表明当外界环境条件变化时可以按照限功率的要求实现单位功率因数并网。

The output power of photovoltaic modules will changes with the variability of external environment such as light intensity and temperature. In order to reduce the volatility of photovoltaic power system and avoid micro grid peak exchanges power with public grid, the constrained production control strategy of photovoltaic power system is studied based on the study of maximum power point tracking（MPPT） control. In other words,taking maximum output power as object under constrained power,and taking constrained output power as object above constrained powerl The two-stage model of grid-connected photovoltaic power system is established,the MPPT and constrained production control strategy of pre- stage Boost circuit are studied, and vector control technology of the post-stage DC-AC converter is researched as well. Finally, the simulation model of the whole system is set up in the MATLAB/SIMULINK, and simulation results show the unity power factor running is realized at the request of constrained pro- duction when external environment changes.