新型Z源光伏并网发电系统

本文提出了一种新型Z源光伏并网发电系统，与传统的Z源光伏并网发电系统相比，具有更高的功率密度，同时光伏电池与逆变桥臂实现了共地，电磁干扰(EMI)也更小。分析了该发电系统的工作原理和调制策略，并提出了一种能够维持直流链峰值电压恒定的并网控制策略，实现了光伏电池的最大功率点跟踪(MPPT)、直流链电压的升压以及网侧电流的单位功率因数运行。仿真和实验结果验证了新型Z源光伏并网发电系统能够适应光伏电池电压的宽范围变化，具有很好的应用前景

New Z-Source Grid-connected PV System

This paper proposes a grid-connected PV system based on the new Z-source inverter,which has higher power density when compared with traditional Z-source grid-connected PV system.In this system,PV array and inverter are common ground, thus EMI is limited.The operation principle and control strategy are presented.This paper also proposes a control strategy to maintain DC-link peak voltage value. This system is able to track the MPP of PV array dynamicly,boost DC-link peak voltage value,synchronize output current with grid voltage,thus transforms power to utility grid with a high power factor. Simulation and experimental results demonstrate that the new Z-source inverte grid-connected PV system,which could adapt well to large-scale variety of PV arry output voltage,has a great future.