基于电网电压矢量定向的双闭环光伏并网逆变系统的研究

Research of Grid-Connected Photovoltaic Inverter Grid-Connected System Based on Double Closed-Loop of Grid Voltage Vector Orientation

针对传统光伏系统并网逆变技术的问题,提出了一种新型的基于电网电压矢量定向的双闭环直接电流控制技术,依据系统动态数学模型构造了直流电压外环和有功、无功电流内环控制系统,同时采用SVPWM技术控制IGBT的通断,实现了光伏并网逆变系统精确的运行在单位功率因数状态。最后,通过对比分析MATLAB仿真与以DSP为控制芯片搭建的两级非隔离式光伏并网逆变系统实验,验证了所提算法的正确性。

For the problem of grid inverter technology in traditional Photo-Voltage（PV）system,a novel direct current control strategy is proposed on the basis of grid voltage vector orientation of the double closed loops,and a control system of DC voltage outer loop and active or reactive current inner loop is built on top of dynamic mathematical model.Meanwhile,combined with SVPWM to control the IGBT,the PV grid inverter system achieves high precision when it runs under lower unit power factor.Finally,through the comparison of MATLAB simulation and the system experiment,in which the two-level and non-isolated type and contravariant DSP is taken as control chip,the accuracy of the method is verified.